1. Field
The present disclosure relates generally to communication systems, and more particularly, to group bearer and bearer selection for multicast/broadcast data transmissions.
2. Background
Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts. Typical wireless communication systems may employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power). Examples of such multiple-access technologies include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, single-carrier frequency division multiple access (SC-FDMA) systems, and time division synchronous code division multiple access (TD-SCDMA) systems.
These multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different wireless devices to communicate on a municipal, national, regional, and even global level. An example of an emerging telecommunication standard is Long Term Evolution (LTE). LTE is a set of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard promulgated by Third Generation Partnership Project (3GPP). It is designed to better support mobile broadband Internet access by improving spectral efficiency, lowering costs, improving services, making use of new spectrum, and better integrating with other open standards using OFDMA on the downlink (DL), SC-FDMA on the uplink (UL), and multiple-input multiple-output (MIMO) antenna technology. However, as the demand for mobile broadband access continues to increase, there exists a need for further improvements in LTE technology. Preferably, these improvements should be applicable to other multi-access technologies and the telecommunication standards that employ these technologies.
In an aspect of the disclosure, a method, a computer program product, and an apparatus are provided. The apparatus may be a user equipment (UE) that receives a multicast/broadcast data transmission via a group bearer. The UE receives a paging message including a type of the group bearer. In addition, the UE determines whether to remain in or change to a radio resource control (RRC) idle mode or an RRC connected mode based on the type of the group bearer received in the paging message.
In an aspect of the disclosure, a method, a computer program product, and an apparatus are provided. The apparatus may be an evolved Node B (eNB) that provides a multicast/broadcast data transmission via a group bearer. The eNB determines a type of the group bearer. In addition, the eNB sends a paging message including the type of the group bearer to a set of UEs.
In an aspect of the disclosure, a method, a computer program product, and an apparatus are provided. The apparatus determines a type of a bearer and establishes the bearer for PTT/PTX communication. The apparatus receives a PTT/PTX message for a set of UEs. The apparatus establishes one of a unicast bearer, a group bearer, or a Multimedia Broadcast Multicast Service (MBMS) bearer based on at least one of the PTT/PTX message or the set of UEs. The apparatus sends the PTT/PTX message through the established bearer to the set of UEs.
The detailed description set forth below in connection with the appended drawings is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details for the purpose of providing a thorough understanding of various concepts. However, it will be apparent to those skilled in the art that these concepts may be practiced without these specific details. In some instances, well known structures and components are shown in block diagram form in order to avoid obscuring such concepts.
Several aspects of telecommunication systems will now be presented with reference to various apparatus and methods. These apparatus and methods will be described in the following detailed description and illustrated in the accompanying drawings by various blocks, modules, components, circuits, steps, processes, algorithms, etc. (collectively referred to as “elements”). These elements may be implemented using electronic hardware, computer software, or any combination thereof. Whether such elements are implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system.
By way of example, an element, or any portion of an element, or any combination of elements may be implemented with a “processing system” that includes one or more processors. Examples of processors include microprocessors, microcontrollers, digital signal processors (DSPs), field programmable gate arrays (FPGAs), programmable logic devices (PLDs), state machines, gated logic, discrete hardware circuits, and other suitable hardware configured to perform the various functionality described throughout this disclosure. One or more processors in the processing system may execute software. Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.
Accordingly, in one or more exemplary embodiments, the functions described may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored on or encoded as one or more instructions or code on a computer-readable medium. Computer-readable media includes computer storage media. Storage media may be any available media that can be accessed by a computer. By way of example, and not limitation, such computer-readable media can comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. Disk and disc, as used herein, includes compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), and floppy disk where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media.
The E-UTRAN includes the evolved Node B (eNB) 106 and other eNBs 108. The eNB 106 provides user and control planes protocol terminations toward the UE 102. The eNB 106 may be connected to the other eNBs 108 via a backhaul (e.g., an X2 interface). The eNB 106 may also be referred to as a base station, a Node B, an access point, a base transceiver station, a radio base station, a radio transceiver, a transceiver function, a basic service set (BSS), an extended service set (ESS), or some other suitable terminology. The eNB 106 provides an access point to the EPC 110 for a UE 102. Examples of UEs 102 include a cellular phone, a smart phone, a session initiation protocol (SIP) phone, a laptop, a personal digital assistant (PDA), a satellite radio, a global positioning system, a multimedia device, a video device, a digital audio player (e.g., MP3 player), a camera, a game console, a tablet, or any other similar functioning device. The UE 102 may also be referred to by those skilled in the art as a mobile station, a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless device, a wireless communications device, a remote device, a mobile subscriber station, an access terminal, a mobile terminal, a wireless terminal, a remote terminal, a handset, a user agent, a mobile client, a client, or some other suitable terminology.
The eNB 106 is connected to the EPC 110. The EPC 110 may include a Mobility Management Entity (MME) 112, other MMEs 114, a Serving Gateway 116, a Multimedia Broadcast Multicast Service (MBMS) Gateway 124, a Broadcast Multicast Service Center (BM-SC) 126, and a Packet Data Network (PDN) Gateway 118. The MME 112 is the control node that processes the signaling between the UE 102 and the EPC 110. Generally, the MME 112 provides bearer and connection management. All user IP packets are transferred through the Serving Gateway 116, which itself is connected to the PDN Gateway 118. The PDN Gateway 118 provides UE IP address allocation as well as other functions. The PDN Gateway 118 is connected to the Operator's IP Services 122. The Operator's IP Services 122 may include the Internet, an intranet, an IP Multimedia Subsystem (IMS), and a PS Streaming Service (PSS). The BM-SC 126 may provide functions for MBMS user service provisioning and delivery. The BM-SC 126 may serve as an entry point for content provider MBMS transmission, may be used to authorize and initiate MBMS Bearer Services within a PLMN, and may be used to schedule and deliver MBMS transmissions. The MBMS Gateway 124 may be used to distribute MBMS traffic to the eNBs (e.g., 106, 108) belonging to an MBSFN area broadcasting a particular service, and may be responsible for session management (start/stop) and for collecting eMBMS related charging information.
The modulation and multiple access scheme employed by the access network 200 may vary depending on the particular telecommunications standard being deployed. In LTE applications, OFDM is used on the DL and SC-FDMA is used on the UL to support both frequency division duplex (FDD) and time division duplex (TDD). As those skilled in the art will readily appreciate from the detailed description to follow, the various concepts presented herein are well suited for LTE applications. However, these concepts may be readily extended to other telecommunication standards employing other modulation and multiple access techniques. By way of example, these concepts may be extended to Evolution-Data Optimized (EV-DO) or Ultra Mobile Broadband (UMB). EV-DO and UMB are air interface standards promulgated by the 3rd Generation Partnership Project 2 (3GPP2) as part of the CDMA2000 family of standards and employs CDMA to provide broadband Internet access to mobile stations. These concepts may also be extended to Universal Terrestrial Radio Access (UTRA) employing Wideband-CDMA (W-CDMA) and other variants of CDMA, such as TD-SCDMA; Global System for Mobile Communications (GSM) employing TDMA; and Evolved UTRA (E-UTRA), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, and Flash-OFDM employing OFDMA. UTRA, E-UTRA, UMTS, LTE and GSM are described in documents from the 3GPP organization. CDMA2000 and UMB are described in documents from the 3GPP2 organization. The actual wireless communication standard and the multiple access technology employed will depend on the specific application and the overall design constraints imposed on the system.
The eNBs 204 may have multiple antennas supporting MIMO technology. The use of MIMO technology enables the eNBs 204 to exploit the spatial domain to support spatial multiplexing, beamforming, and transmit diversity. Spatial multiplexing may be used to transmit different streams of data simultaneously on the same frequency. The data streams may be transmitted to a single UE 206 to increase the data rate or to multiple UEs 206 to increase the overall system capacity. This is achieved by spatially precoding each data stream (i.e., applying a scaling of an amplitude and a phase) and then transmitting each spatially precoded stream through multiple transmit antennas on the DL. The spatially precoded data streams arrive at the UE(s) 206 with different spatial signatures, which enables each of the UE(s) 206 to recover the one or more data streams destined for that UE 206. On the UL, each UE 206 transmits a spatially precoded data stream, which enables the eNB 204 to identify the source of each spatially precoded data stream.
Spatial multiplexing is generally used when channel conditions are good. When channel conditions are less favorable, beamforming may be used to focus the transmission energy in one or more directions. This may be achieved by spatially precoding the data for transmission through multiple antennas. To achieve good coverage at the edges of the cell, a single stream beamforming transmission may be used in combination with transmit diversity.
In the detailed description that follows, various aspects of an access network will be described with reference to a MIMO system supporting OFDM on the DL. OFDM is a spread-spectrum technique that modulates data over a number of subcarriers within an OFDM symbol. The subcarriers are spaced apart at precise frequencies. The spacing provides “orthogonality” that enables a receiver to recover the data from the subcarriers. In the time domain, a guard interval (e.g., cyclic prefix) may be added to each OFDM symbol to combat inter-OFDM-symbol interference. The UL may use SC-FDMA in the form of a DFT-spread OFDM signal to compensate for high peak-to-average power ratio (PAPR).
A UE may be assigned resource blocks 410a, 410b in the control section to transmit control information to an eNB. The UE may also be assigned resource blocks 420a, 420b in the data section to transmit data to the eNB. The UE may transmit control information in a physical UL control channel (PUCCH) on the assigned resource blocks in the control section. The UE may transmit only data or both data and control information in a physical UL shared channel (PUSCH) on the assigned resource blocks in the data section. A UL transmission may span both slots of a subframe and may hop across frequency.
A set of resource blocks may be used to perform initial system access and achieve UL synchronization in a physical random access channel (PRACH) 430. The PRACH 430 carries a random sequence and cannot carry any UL data/signaling. Each random access preamble occupies a bandwidth corresponding to six consecutive resource blocks. The starting frequency is specified by the network. That is, the transmission of the random access preamble is restricted to certain time and frequency resources. There is no frequency hopping for the PRACH. The PRACH attempt is carried in a single subframe (1 ms) or in a sequence of few contiguous subframes and a UE can make only a single PRACH attempt per frame (10 ms).
In the user plane, the L2 layer 508 includes a media access control (MAC) sublayer 510, a radio link control (RLC) sublayer 512, and a packet data convergence protocol (PDCP) 514 sublayer, which are terminated at the eNB on the network side. Although not shown, the UE may have several upper layers above the L2 layer 508 including a network layer (e.g., IP layer) that is terminated at the PDN gateway 118 on the network side, and an application layer that is terminated at the other end of the connection (e.g., far end UE, server, etc.).
The PDCP sublayer 514 provides multiplexing between different radio bearers and logical channels. The PDCP sublayer 514 also provides header compression for upper layer data packets to reduce radio transmission overhead, security by ciphering the data packets, and handover support for UEs between eNBs. The RLC sublayer 512 provides segmentation and reassembly of upper layer data packets, retransmission of lost data packets, and reordering of data packets to compensate for out-of-order reception due to hybrid automatic repeat request (ARQ) (HARQ). The MAC sublayer 510 provides multiplexing between logical and transport channels. The MAC sublayer 510 is also responsible for allocating the various radio resources (e.g., resource blocks) in one cell among the UEs. The MAC sublayer 510 is also responsible for HARQ operations.
In the control plane, the radio protocol architecture for the UE and eNB is substantially the same for the physical layer 506 and the L2 layer 508 with the exception that there is no header compression function for the control plane. The control plane also includes a radio resource control (RRC) sublayer 516 in Layer 3 (L3 layer). The RRC sublayer 516 is responsible for obtaining radio resources (e.g., radio bearers) and for configuring the lower layers using RRC signaling between the eNB and the UE.
The transmit (TX) processor 616 implements various signal processing functions for the L1 layer (i.e., physical layer). The signal processing functions include coding and interleaving to facilitate forward error correction (FEC) at the UE 650 and mapping to signal constellations based on various modulation schemes (e.g., binary phase-shift keying (BPSK), quadrature phase-shift keying (QPSK), M-phase-shift keying (M-PSK), M-quadrature amplitude modulation (M-QAM)). The coded and modulated symbols are then split into parallel streams. Each stream is then mapped to an OFDM subcarrier, multiplexed with a reference signal (e.g., pilot) in the time and/or frequency domain, and then combined together using an Inverse Fast Fourier Transform (IFFT) to produce a physical channel carrying a time domain OFDM symbol stream. The OFDM stream is spatially precoded to produce multiple spatial streams. Channel estimates from a channel estimator 674 may be used to determine the coding and modulation scheme, as well as for spatial processing. The channel estimate may be derived from a reference signal and/or channel condition feedback transmitted by the UE 650. Each spatial stream may then be provided to a different antenna 620 via a separate transmitter 618TX. Each transmitter 618TX may modulate an RF carrier with a respective spatial stream for transmission, if applicable.
At the UE 650, each receiver 654RX receives a signal through its respective antenna 652. Each receiver 654RX recovers information modulated onto an RF carrier and provides the information to the receive (RX) processor 656. The RX processor 656 implements various signal processing functions of the L1 layer. The RX processor 656 may perform spatial processing on the information to recover any spatial streams destined for the UE 650. If multiple spatial streams are destined for the UE 650, they may be combined by the RX processor 656 into a single OFDM symbol stream. The RX processor 656 then converts the OFDM symbol stream from the time-domain to the frequency domain using a Fast Fourier Transform (FFT). The frequency domain signal comprises a separate OFDM symbol stream for each sub carrier of the OFDM signal. The symbols on each subcarrier, and the reference signal, are recovered and demodulated by determining the most likely signal constellation points transmitted by the eNB 610. These soft decisions may be based on channel estimates computed by the channel estimator 658. The soft decisions are then decoded and deinterleaved to recover the data and control signals that were originally transmitted by the eNB 610 on the physical channel. The data and control signals are then provided to the controller/processor 659.
The controller/processor 659 implements the L2 layer. The controller/processor can be associated with a memory 660 that stores program codes and data. The memory 660 may be referred to as a computer-readable medium. In the UL, the controller/processor 659 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, control signal processing to recover upper layer packets from the core network. The upper layer packets are then provided to a data sink 662, which represents all the protocol layers above the L2 layer. Various control signals may also be provided to the data sink 662 for L3 processing. The controller/processor 659 is also responsible for error detection using an acknowledgement (ACK) and/or negative acknowledgement (NACK) protocol to support HARQ operations.
In the UL, a data source 667 is used to provide upper layer packets to the controller/processor 659. The data source 667 represents all protocol layers above the L2 layer. Similar to the functionality described in connection with the DL transmission by the eNB 610, the controller/processor 659 implements the L2 layer for the user plane and the control plane by providing header compression, ciphering, packet segmentation and reordering, and multiplexing between logical and transport channels based on radio resource allocations by the eNB 610. The controller/processor 659 is also responsible for HARQ operations, retransmission of lost packets, and signaling to the eNB 610.
Channel estimates derived by a channel estimator 658 from a reference signal or feedback transmitted by the eNB 610 may be used by the TX processor 668 to select the appropriate coding and modulation schemes, and to facilitate spatial processing. The spatial streams generated by the TX processor 668 may be provided to different antenna 652 via separate transmitters 654TX. Each transmitter 654TX may modulate an RF carrier with a respective spatial stream for transmission.
The UL transmission is processed at the eNB 610 in a manner similar to that described in connection with the receiver function at the UE 650. Each receiver 618RX receives a signal through its respective antenna 620. Each receiver 618RX recovers information modulated onto an RF carrier and provides the information to a RX processor 670. The RX processor 670 may implement the L1 layer.
The controller/processor 675 implements the L2 layer. The controller/processor 675 can be associated with a memory 676 that stores program codes and data. The memory 676 may be referred to as a computer-readable medium. In the UL, the control/processor 675 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, control signal processing to recover upper layer packets from the UE 650. Upper layer packets from the controller/processor 675 may be provided to the core network. The controller/processor 675 is also responsible for error detection using an ACK and/or NACK protocol to support HARQ operations.
A UE can camp on an LTE cell to discover the availability of eMBMS service access and a corresponding access stratum configuration. In a first step, the UE may acquire a system information block (SIB) 13 (SIB13). In a second step, based on the SIB13, the UE may acquire an MBSFN Area Configuration message on an MCCH. In a third step, based on the MBSFN Area Configuration message, the UE may acquire an MCH scheduling information (MSI) MAC control element. The SIB13 indicates (1) an MBSFN area identifier of each MBSFN area supported by the cell; (2) information for acquiring the MCCH such as an MCCH repetition period (e.g., 32, 64, . . . , 256 frames), an MCCH offset (e.g., 0, 1, . . . , 10 frames), an MCCH modification period (e.g., 512, 1024 frames), a signaling modulation and coding scheme (MCS), subframe allocation information indicating which subframes of the radio frame as indicated by repetition period and offset can transmit MCCH; and (3) an MCCH change notification configuration. There is one MBSFN Area Configuration message for each MBSFN area. The MBSFN Area Configuration message indicates both (1) a temporary mobile group identity (TMGI) and an optional session identifier of each MTCH identified by a logical channel identifier within the PMCH, (2) allocated resources (i.e., radio frames and subframes) for transmitting each PMCH of the MBSFN area and the allocation period (e.g., 4, 8, . . . , 256 frames) of the allocated resources for all the PMCHs in the area, and (3) an MCH scheduling period (MSP) (e.g., 8, 16, 32, . . . , or 1024 radio frames) over which the MSI MAC control element is transmitted.
With an increase in eMBMS popularity, adaptively configuring multicast broadcast service areas (e.g., MBSFN service areas, MBMS service areas) or MBSFN areas based on available resources and user distribution could be beneficial. Through the adaptive configuration of multicast broadcast service areas/MBSFN areas, cells may be added or removed according to actual needs. By allowing the adaptive configuration of multicast broadcast service areas/MBSFN areas, system resource utilization may be increased, easy of operations/configurations may be improved, interference may be reduced through the use of tiers, and eMBMS may be provided on demand when a sufficient number of users desire the same service.
Based on the UE count information, the MCE or BM-SC determines whether a base station should be part of the multicast broadcast service area 812 and/or an MBSFN area within the multicast broadcast service area 812. The MCE or BM-SC may make the determination further based on the received signal quality information. For example, upon receiving the UE count information and signal quality information, the MCE or BM-SC may determine that the eNB 804c should be part of the multicast broadcast service area 812 and/or be a part of an MBSFN area within the multicast broadcast service area 812. The MCE or BM-SC may make such a determination based on providing MBSFN (MBMS) services for any UEs served by the eNB 804c, such as the UE 826, or based on providing improved (e.g., improved RSRP, RSRQ, RSSI, SINR) MBSFN services for any UEs on the cell edge of the eNB 804c, such as for the UEs 820, 822. Specifically, the MCE or BM-SC may determine based on the UE count information that a sufficient number of UEs within the coverage of the eNB 804c, such as the UE 826, would like to receive MBSFN services from the eNB 804c. Furthermore, the MCE or BM-SC may determine based on the UE count information that a sufficient number of UEs, such as the UEs 820, 822, reported a signal quality from the eNB 802b less than a first quality threshold and a signal quality from the eNB 804c greater than a second quality threshold. The MCE or BM-SC may then determine that the UEs 820, 822 are on the edge of the cells between the eNBs 802b, 804c, and may therefore benefit from receiving MBSFN services from the eNB 804c.
As shown in
The MCE or BM-SC may also determine a broadcasting tier for the eNB upon determining the eNB should be part of the multicast broadcast service area 812 and/or particular MBSFN areas. The broadcasting tier may be a first tier (tier 1) 840 for broadcasting a system information block (SIB) indicating an MCCH configuration for the MCCH; a second tier (tier 2) 842 for broadcasting the SIB indicating the MCCH configuration for the MCCH and broadcasting the MCCH indicating an MTCH configuration; or a third tier (tier 3) 844 for broadcasting the SIB indicating the MCCH configuration for the MCCH, broadcasting the MCCH indicating the MTCH configuration, and broadcasting the MTCH. The tiers allow for particular adaptive eNBs to be configured to provide different levels of MBSFN services. For example, if an adaptive eNB serves many UEs interested in receiving MBSFN services or the broadcasting of the MTCH would improve cell edge UEs served by other eNBs, the adaptive eNB may be configured in tier 3. However, if the adaptive eNB serves few or no UEs and the broadcasting of the MTCH would provide no to little improvement to cell edge UEs served by other eNBs, the adaptive eNB may be configured in tier 2 or tier 1. As shown in
When the MCE/BM-SC determines that an adaptive eNB should not be a part of the multicast broadcast service area 812, the multicast broadcast service area decreases in size. When the MCE/BM-SC determines that an adaptive eNB should be a part of the multicast broadcast service area 812, the multicast broadcast service area increases in size. As such, the determination of whether adaptive eNBs should be part of the multicast broadcast service area 812 ultimately changes the size of the multicast broadcast service area 812, usually on the edges of the multicast broadcast service area 812. As discussed supra, each multicast broadcast service area 812 may support up to eight MBSFN areas. When the MCE/BM-SC determines that an adaptive eNB should not be a part of an MBSFN area of the multicast broadcast service area 812, the multicast broadcast service area 812 may not change in size. Instead, the services provided by one of the cells in the multicast broadcast service area 812 changes. The adaptive multicast broadcast service area and adaptive MBSFN areas allow for areas associated with MBSFN/MBMS services to change based on UE mobility, UE multicast broadcast service interest, multicast broadcast reception quality improvement, etc.
In logical function LF1, the eNBs may extract RF measurements, obtain the list of cells, and determine a count of UEs (i.e., UE count information) that would like to receive MBSFN services or particular MBSFN services. The eNBs may then rank the list of cells. In the logical function LF2, the eNBs may transmit elaborated information to the MCE and receive an updated configuration for the multicast broadcast service area and/or MBSFN areas. The elaborated information may include the RF measurements, list of cells, and the UE count information. Alternatively or additionally, the elaborated information may include the ranked list of cells. The eNBs send input I2 to the MCE. The input I2 includes candidate neighbors, including RF statistics and observed sets. In logical function LF3, the MCE receives the list information, executes MBSFN area optimization algorithms to maximize a goal function for adjusting to the network load and MBMS user distribution, and transmits updated cluster sets (i.e., multicast broadcast service area and/or MBSFN area configurations) back to the eNBs indicating whether the eNBs should be part of the multicast broadcast service area and/or part of particular MBSFN areas.
In logical function LF1, the eNBs extract RF measurements and obtain the list of cells. The eNBs may also determine a count of UEs (i.e., UE count information) that would like to receive MBSFN services or particular MBSFN services. The eNBs may also rank the list of cells. In the logical function LF2, the eNBs transmit elaborated information to the MCE and receive an updated multicast broadcast service area and/or MBSFN area. The elaborated information may include the RF measurements and list of cells. The elaborated information may further include the UE count information. Alternatively or additionally, the elaborated information may include the ranked list of cells if the eNBs rank the cells. The eNBs send input I2 to the MCE. The input I2 includes candidate neighbors, including RF statistics and observed sets. In logical function LF3, the MCE receives the list information, executes MBSFN area optimization algorithms to maximize a goal function for adjusting to the network load and MBMS user distribution, and transmits updated cluster sets (i.e., multicast broadcast service area and/or MBSFN area configurations) back to the eNBs indicating whether the eNBs should be part of the multicast broadcast service area and/or part of particular MBSFN areas. In logical function LF4, the BM-SC detects a high attach rate for (e.g., receiving, desire to receive) the same content from the UEs in the same location. In logical function LF5, the BM-SC determines the multicast broadcast service area and/or particular MBSFN areas for some eNBs and indicates the MBSFN configuration to the MCE through the MBMS Gateway (MBMS-GW) and MME.
Adaptive MBSFN, discussed supra in relation to
In one configuration, a group or an MBMS user service may be preconfigured. For each prearranged group, the eMBMS system may pre-assign a unique multicast IP address/port and a TMGI. One or more TMGIs can be pre-allocated. For PTX, one TMGI may be used for all file downloading. A file delivery table (FDT) instance of a scheduling fragment may be used by a UE for determining the files to be downloaded by the UE. UEs may be aware of the MBMS user service identifier (ID) or the TMGI(s) associated with the group addresses, along with other group information for the groups of which the UEs are a member. The MBMS user service ID may be used to hide transport details from a UE. eMBMS middleware may manage transport details with a service announcement file. When MBMS is preconfigured, the MBMS is effectively always on, and the BM-SC 1606 does not perform the eMBMS session setup step.
If TMGIs are not pre-allocated for PTT/PTX (e.g., the group or the MBMS user service is not pre-configured) (see
Call latency may be on the order of seconds for PTT/PTX through an MBMS bearer. Call latency should preferably be less than 300 ms. In one configuration, the MBMS bearer may be pre-setup or the MBMS session may be preconfigured to be immediately available. When the MBMS session is not being used for a group call, the resources may be allocated to unicast traffic. In one configuration, call latency may be reduced by reducing an LTE radio interface call setup time. In one configuration, the target radio interface call setup may be performed in parallel with the originator call setup interface (see
Talk burst control messages (e.g., the talk burst confirm messages of
Adaptive SFN, discussed in relation to
The group call setup signaling may include service announcement and discovery information for an MBMS bearer. The group call setup signaling may be a SIP invitation request. The SIP invitation request may include a list of target UEs. A UE may set up the unicast bearer by sending an RRC connection request, receiving an RRC connection setup response, and sending an RRC connection complete message. The group call setup signaling may be sent with the RRC connection complete message. For example, referring to
In step 2006, a UE may receive a talk burst control message through an MBMS bearer. In step 2006, the talk burst control message may include at least one of an indication that PTT/PTX communication can be sent, an indication that PTT/PTX communication cannot be sent, or scheduling information for indicating when PTT/PTX communication can be sent. The talk burst control message may be received through one of a UDP, a SIP, an HTTP, an FDT instance, or OMA signaling. For example, referring to
A UE may send a first talk burst control message encrypted based on a first set of MTKs. In addition, the UE may receive a second talk burst control message encrypted based on a second set of MTKs different than the first set of MTKs. Furthermore, the UE may send PTT/PTX data on an MBMS bearer based on a third set of MTKs different than the first set of MTKs and the second set of MTKs. For example, referring to
In step 2008, the UE sends PTT/PTX data to be transmitted to one or more target UEs over an MBMS bearer. For example, referring to
The apparatus may include additional modules that perform each of the steps of the algorithm in the aforementioned flow chart of
The processing system 2214 may be coupled to a transceiver 2210. The transceiver 2210 is coupled to one or more antennas 2220. The transceiver 2210 provides a means for communicating with various other apparatus over a transmission medium. The transceiver 2210 receives a signal from the one or more antennas 2220, extracts information from the received signal, and provides the extracted information to the processing system 2214. In addition, the transceiver 2210 receives information from the processing system 2214, and based on the received information, generates a signal to be applied to the one or more antennas 2220. The processing system 2214 includes a processor 2204 coupled to a computer-readable medium 2206. The processor 2204 is responsible for general processing, including the execution of software stored on the computer-readable medium 2206. The software, when executed by the processor 2204, causes the processing system 2214 to perform the various functions described supra for any particular apparatus. The computer-readable medium 2206 may also be used for storing data that is manipulated by the processor 2204 when executing software. The processing system further includes at least one of the modules 2110, 2112, 2114, 2116. The modules may be software modules running in the processor 2204, resident/stored in the computer readable medium 2206, one or more hardware modules coupled to the processor 2204, or some combination thereof. The processing system 2214 may be a component of the UE 650 and may include the memory 660 and/or at least one of the TX processor 668, the RX processor 656, and the controller/processor 659.
In one configuration, the apparatus 2102/2102′ for wireless communication includes means for setting up a unicast bearer with an eNB, and means for sending group call setup signaling to the eNB while setting up the unicast bearer. The apparatus may further include means for receiving a talk burst control message through an MBMS bearer. The apparatus may further include means for sending a first talk burst control message encrypted based on a first set of MTKs, means for receiving a second talk burst control message encrypted based on a second set of MTKs different than the first set of MTKs, and means for sending PTT/PTX data based on a third set of MTKs different than the first set of MTKs and the second set of MTKs. The apparatus may further includes means for sending PTT/PTX data to be transmitted to one or more target UEs over an MBMS bearer. The aforementioned means may be one or more of the aforementioned modules of the apparatus 2102 and/or the processing system 2214 of the apparatus 2102′ configured to perform the functions recited by the aforementioned means. As described supra, the processing system 2214 may include the TX Processor 668, the RX Processor 656, and the controller/processor 659. As such, in one configuration, the aforementioned means may be the TX Processor 668, the RX Processor 656, and the controller/processor 659 configured to perform the functions recited by the aforementioned means.
The group call setup signaling may be service announcement and discovery information for an MBMS bearer. The group call setup signaling may include a SIP invitation request. A UE may set up the unicast bearer by sending an RRC connection request, receiving an RRC connection setup response, and sending an RRC connection complete message. A UE may receive the group call setup signaling with the RRC connection setup response. For example, referring to
In step 2306, a UE receives a talk burst control message through an MBMS bearer. The talk burst control message may be at least one of an identity of a user sending the PTT/PTX communication or scheduling information for indicating when PTT/PTX communication is received. A UE may receive the talk burst control message through one of a UDP, a SIP, an HTTP, an FDT instance, or OMA signaling. For example, referring to
In one configuration, a session of the MBMS is always on with a preconfigured TMGI or MBMS user service identifier. Referring to
In one configuration, in step 2306, a UE receives a talk burst control message encrypted based on a first set of MTKs. In step 2308, the UE receives PTT/PTX data on an MBMS bearer based on a second set of MTKs different than the first set of MTKs. For example, referring to
The apparatus may include additional modules that perform each of the steps of the algorithm in the aforementioned flow chart of
The processing system 2514 may be coupled to a transceiver 2510. The transceiver 2510 is coupled to one or more antennas 2520. The transceiver 2510 provides a means for communicating with various other apparatus over a transmission medium. The transceiver 2510 receives a signal from the one or more antennas 2520, extracts information from the received signal, and provides the extracted information to the processing system 2514. In addition, the transceiver 2510 receives information from the processing system 2514, and based on the received information, generates a signal to be applied to the one or more antennas 2520. The processing system 2514 includes a processor 2504 coupled to a computer-readable medium 2506. The processor 2504 is responsible for general processing, including the execution of software stored on the computer-readable medium 2506. The software, when executed by the processor 2504, causes the processing system 2514 to perform the various functions described supra for any particular apparatus. The computer-readable medium 2506 may also be used for storing data that is manipulated by the processor 2504 when executing software. The processing system further includes at least one of the modules 2410, 2412, 2414, 2416. The modules may be software modules running in the processor 2504, resident/stored in the computer readable medium 2506, one or more hardware modules coupled to the processor 2504, or some combination thereof. The processing system 2514 may be a component of the UE 650 and may include the memory 660 and/or at least one of the TX processor 668, the RX processor 656, and the controller/processor 659.
In one configuration, the apparatus 2402/2402′ for wireless communication includes means for setting up a unicast bearer with an eNB, and means for receiving group call setup signaling from the eNB while setting up the unicast bearer. The apparatus may further include means for receiving a talk burst control message through an MBMS bearer. The apparatus may further include means for receiving PTT/PTX data over an MBMS bearer. The apparatus may further include means for receiving a talk burst control message encrypted based on a first set of MTKs, and means for receiving PTT/PTX data on an MBMS bearer based on a second set of MTKs different than the first set of MTKs. The aforementioned means may be one or more of the aforementioned modules of the apparatus 2402 and/or the processing system 2514 of the apparatus 2402′ configured to perform the functions recited by the aforementioned means. As described supra, the processing system 2514 may include the TX Processor 668, the RX Processor 656, and the controller/processor 659. As such, in one configuration, the aforementioned means may be the TX Processor 668, the RX Processor 656, and the controller/processor 659 configured to perform the functions recited by the aforementioned means.
The group page may include a TMGI. If the group page includes a TMGI, the UE may tune to an MBMS bearer corresponding to the TMGI, and then receive the group call setup signaling on the MBMS bearer. The group call setup signaling may include service announcement and discovery information for an MBMS bearer. The service announcement and discovery information may include a security key. The security key may be an MSK protected by an MGK. The group call setup signaling may be received on an MBMS bearer. The group call setup signaling may include a SIP invitation request. For example, referring to
In step 2606, the UE receives a talk burst control message through an MBMS bearer. The talk burst control message may include at least one of an identity of a user sending the PTT/PTX communication or scheduling information for indicating when PTT/PTX communication is received. For example, referring to
In one configuration, a session of the MBMS is always on with a preconfigured TMGI or MBMS user service identifier. For example, referring to
In one configuration, in step 2606, a UE may receive a talk burst control message encrypted based on a first set of MTKs. In step 2608, the UE may receive PTT/PTX data on an MBMS bearer based on a second set of MTKs different than the first set of MTKs. For example, referring to
The apparatus may include additional modules that perform each of the steps of the algorithm in the aforementioned flow chart of
The processing system 2814 may be coupled to a transceiver 2810. The transceiver 2810 is coupled to one or more antennas 2820. The transceiver 2810 provides a means for communicating with various other apparatus over a transmission medium. The transceiver 2810 receives a signal from the one or more antennas 2820, extracts information from the received signal, and provides the extracted information to the processing system 2814. In addition, the transceiver 2810 receives information from the processing system 2814, and based on the received information, generates a signal to be applied to the one or more antennas 2820. The processing system 2814 includes a processor 2804 coupled to a computer-readable medium 2806. The processor 2804 is responsible for general processing, including the execution of software stored on the computer-readable medium 2806. The software, when executed by the processor 2804, causes the processing system 2814 to perform the various functions described supra for any particular apparatus. The computer-readable medium 2806 may also be used for storing data that is manipulated by the processor 2804 when executing software. The processing system further includes at least one of the modules 2710, 2712, 2714, 2716. The modules may be software modules running in the processor 2804, resident/stored in the computer readable medium 2806, one or more hardware modules coupled to the processor 2804, or some combination thereof. The processing system 2814 may be a component of the UE 650 and may include the memory 660 and/or at least one of the TX processor 668, the RX processor 656, and the controller/processor 659.
In one configuration, the apparatus 2702/2702′ for wireless communication includes means for receiving a group page while in an RRC idle state, and means for receiving group call setup signaling based on information in the group page. The apparatus may further include means for tuning to an MBMS bearer corresponding to the TMGI when the group page includes a TMGI. In such a configuration, the group call setup signaling is received on the MBMS bearer. The apparatus may further include means for receiving a talk burst control message through an MBMS bearer. The apparatus may further include means for receiving PTT/PTX data on an MBMS bearer. The apparatus may further include means for receiving a talk burst control message encrypted based on a first set of MTKs, and means for receiving PTT/PTX data on an MBMS bearer based on a second set of MTKs different than the first set of MTKs. The aforementioned means may be one or more of the aforementioned modules of the apparatus 2702 and/or the processing system 2814 of the apparatus 2702′ configured to perform the functions recited by the aforementioned means. As described supra, the processing system 2814 may include the TX Processor 668, the RX Processor 656, and the controller/processor 659. As such, in one configuration, the aforementioned means may be the TX Processor 668, the RX Processor 656, and the controller/processor 659 configured to perform the functions recited by the aforementioned means.
The network may receive a list of the target UEs for PTT/PTX communication from the originating UE. With respect to adaptive MBSFNs, the network may determine whether a base station should be part of at least one of a multicast broadcast service area or an MBSFN area based on a location of the originating UE and the target UEs. In addition, the network may send to the base station information indicating whether the base station should be part of the at least one of the multicast broadcast service area or the MBSFN area. The network may setup the MBMS session in the at least one of the multicast broadcast service area or the MBSFN area. The network may modify the at least one of the multicast broadcast service area or the MBSFN area based on count information associated with the target UEs. Count information was discussed supra with respect to
The group call setup signaling may include service announcement and discovery information for an MBMS bearer. The service announcement and discovery information may include a security key. The security key may be an MSK protected by an MGK. The group call setup signaling may include a SIP invitation request. The group call setup signaling may be sent on an MBMS bearer.
The network may set up a unicast bearer with the target UEs by receiving an RRC connection request, sending an RRC connection setup response, and receiving an RRC connection complete message. The group call setup signaling may be sent with the RRC connection setup response. In step 2908, the network may send a talk burst control message through an MBMS bearer. The talk burst control message may include at least one of an identity of a user sending the PTT/PTX communication or scheduling information for indicating when PTT/PTX communication is received. The talk burst control message may include at least one of an indication that PTT/PTX communication can be sent, an indication that PTT/PTX communication cannot be sent, or scheduling information for indicating when PTT/PTX communication can be sent. The talk burst control message may be sent through one of a UDP, a SIP, an HTTP, an FDT instance, or OMA signaling.
In one configuration, a session of the MBMS is always on with a preconfigured TMGI or MBMS user service identifier. If a session of the MBMS is always on, then the MBMS session establish step and the MBMS session setup step of
The network may send a group page to the target UEs. The group page may include a TMGI. The network may send the group call setup signaling on an MBMS bearer corresponding to the TMGI. For example, referring to
In one configuration, the network receives a first talk burst control message from the originating UE. The first talk burst control message is encrypted based on a first set of MTKs. The network sends a second talk burst control message to the originating UE. The second talk burst control message is encrypted based on a second set of MTKs different than the first set of MTKs. The network sends a third talk burst control message to the target UEs. The third talk burst control message is encrypted based on the second set of MTKs. The network receives PTT/PTX data encrypted based on a third set of MTKs different than the first set of MTKs and the second set of MTKs. The network sends the received PTT/PTX data on an MBMS bearer.
The apparatus may include additional modules that perform each of the steps of the algorithm in the aforementioned flow chart of
The processing system 3114 may be coupled to a transceiver 3110. The transceiver 3110 is coupled to one or more antennas 3120. The transceiver 3110 provides a means for communicating with various other apparatus over a transmission medium. The transceiver 3110 receives a signal from the one or more antennas 3120, extracts information from the received signal, and provides the extracted information to the processing system 3114. In addition, the transceiver 3110 receives information from the processing system 3114, and based on the received information, generates a signal to be applied to the one or more antennas 3120. The processing system 3114 includes a processor 3104 coupled to a computer-readable medium 3106. The processor 3104 is responsible for general processing, including the execution of software stored on the computer-readable medium 3106. The software, when executed by the processor 3104, causes the processing system 3114 to perform the various functions described supra for any particular apparatus. The computer-readable medium 3106 may also be used for storing data that is manipulated by the processor 3104 when executing software. The processing system further includes at least one of the modules 3010, 3012, 3014, 3016. The modules may be software modules running in the processor 3104, resident/stored in the computer readable medium 3106, one or more hardware modules coupled to the processor 3104, or some combination thereof.
In one configuration, the apparatus 3002/3002′ for wireless communication includes means for setting up an MBMS session for PTT/PTX communication for an originating UE and target UEs, and means for sending group call setup signaling to the originating UE and the target UEs. The apparatus may further include means for receiving a list of the target UEs for PTT/PTX communication from the originating UE. The apparatus may further include means for determining whether a base station should be part of at least one of a multicast broadcast service area or an MBSFN area based on a location of the originating UE and the target UEs. The apparatus may further include means for sending to the base station information indicating whether the base station should be part of the at least one of the multicast broadcast service area or the MBSFN area. The MBMS session may be set up in the at least one of the multicast broadcast service area or the MBSFN area. The apparatus may further include means for modifying the at least one of the multicast broadcast service area or the MBSFN area based on count information associated with the target UEs. The apparatus may further include means for setting up a unicast bearer with the target UEs by receiving an RRC connection request, sending an RRC connection setup response, and receiving an RRC connection complete message. The group call setup signaling may be sent with the RRC connection setup response. The apparatus may further include means for sending a talk burst control message through an MBMS bearer. The apparatus may further include means for sending PTT/PTX data, received from the originating UE, on an MBMS bearer to the target UEs. The apparatus may further include means for sending a talk burst control message encrypted based on a first set of MTKs, and means for sending PTT/PTX data over MBMS based on a second set of MTKs different than the first set of MTKs. The apparatus may further include mean for sending a group page to the target UEs. The apparatus may further include means for receiving a first talk burst control message from the originating UE. The first talk burst control message may be encrypted based on a first set of MTKs. The apparatus may further include means for sending a second talk burst control message to the originating UE. The second talk burst control message may be encrypted based on a second set of MTKs different than the first set of MTKs. The apparatus may further include means for sending a third talk burst control message to the target UEs. The third talk burst control message may be encrypted based on the second set of MTKs. The apparatus may further include means for receiving PTT/PTX data encrypted based on a third set of MTKs different than the first set of MTKs and the second set of MTKs. The apparatus may further include means for sending the received PTT/PTX data on an MBMS bearer. The aforementioned means may be one or more of the aforementioned modules of the apparatus 3002 and/or the processing system 3114 of the apparatus 3002′ configured to perform the functions recited by the aforementioned means.
Furthermore, as shown in
As discussed supra, the receiving type may be connected, hybrid, or idle. If the receiving type is connected, target UEs should be in an RRC connected state to receive the multicast/broadcast data transmission. UEs in an RRC connected state may report CQI to the serving eNB. The serving eNB receives the CQI from the target UEs, determines an MCS based on the received CQI, and sends the multicast/broadcast data transmission at the determined MCS. In a first configuration, the serving eNB determines a worst CQI (i.e., a CQI corresponding to a lowest MCS) and sends the multicast/broadcast data transmission at an MCS corresponding to the worst CQI. Accordingly, all of the target UEs may receive the multicast/broadcast data transmission, as the multicast/broadcast data transmission is sent with an MCS that allows the target UEs with the worst received signal quality to be able to decode successfully the multicast/broadcast data transmission. In a second configuration, the serving eNB determines an MCS that would allow a particular percentage of the target UEs to receive the multicast/broadcast data transmission, and sends the multicast/broadcast data transmission at that MCS. In the second configuration, the serving eNB may send the multicast/broadcast data transmission with a higher MCS than in the first configuration.
If the receiving type is idle, target UEs do not send CQI feedback in relation to the multicast/broadcast data transmission. The target UEs may send CQI feedback for other purposes, such as for example, because the target UEs are in an RRC connected state. That is, if the receiving type is idle, target UEs in an RRC idle state need not change to an RRC connected state to receive the multicast/broadcast data transmission. In addition, target UEs in an RRC connected state need not maintain the RRC connected state to receive the multicast/broadcast data transmission. Furthermore, serving eNBs do not take into account received CQI (e.g., from target UEs in an RRC connected state) when sending the multicast/broadcast data transmission to the target UEs. Serving eNBs may send the multicast/broadcast data transmission at a low MCS or a lowest possible MCS so that a sufficient number of target UEs receive the multicast/broadcast data transmission.
If the receiving type is hybrid (i.e., a hybrid of the idle and connected receiving types), target UEs need not enter an RRC connected state to receive multicast/broadcast data transmission. However, if a target UE has a receiving signal quality less than a signal quality threshold (e.g., RSRP, RSRQ, RSSI, or SINR is less than a threshold), the target UE may enter an RRC connected state in order to provide CQI feedback to the serving eNB. The serving eNB takes into account CQI received from target UEs when determining an MCS for sending the multicast/broadcast data transmission. The serving eNB may indicate the signal quality threshold at which a target UE should enter an RRC connected state within the group bearer parameters (provided in step 6). Accordingly, target UEs with a received signal quality less than the signal quality threshold may enter an RRC connected state, and target UEs with a received signal quality greater than the signal quality threshold need not enter into an RRC connected state. A target UE may use a cell reselection parameter (e.g., Sintersearch) as the signal quality threshold. Even if the receiving signal quality is greater than the signal quality threshold, target UEs may change to an RRC connected state when a cell change is needed (for example, a handover to another cell).
When the receiving type is connected or hybrid and a target UE is in an RRC connected state, the target UE reports CQI, and additionally may report an ACK and/or NACK so that the serving eNB can schedule the group bearer to ensure reception quality. When the serving eNB receives a NACK, the serving eNB re-transmits the multicast/broadcast data transmission packet that was not properly received. Using a packet switched handover (PSHO) procedure, the serving eNB can hand over a UE to a target cell when necessary. As part of the handover, the serving eNB may send the group bearer context information to the target cell. When the receiving type is idle and a UE enters a cell without a current interest in receiving multicast/broadcast data transmission, the UE may initiate a service request procedure to request a group bearer establishment.
With respect to sending ACK/NACKs by the UE, in an implicit ACK/NACK resource mapping rule, all UEs send ACK/NACK on the same resource in UL, which may result in an ACK/NACK collision. A semi-static configuration may be used to specify ACK/NACK resources for each UE. However, when multiple UEs are in the same group, multiple ACK/NACK resources need to be allocated. In one configuration, if one UE within a group fails to receive a multicast/broadcast data transmission packet, the serving eNB will retransmit the multicast/broadcast data transmission packet to all the UEs in the group. The serving eNB may configure UEs to use PUCCH format 1 for sending ACK/NACK. Accordingly, UEs that successfully decode the multicast/broadcast data transmission packet will not ACK, and UEs that fail to decode the multicast/broadcast data transmission packet will send a NACK on the same ACK/NACK resource according to an implicit mapping rule on the first control channel element (CCE) index in the PDCCH associated with the G-RNTI. The ACK/NACK resource may be associated with a PDCCH used for scheduling the multicast/broadcast data transmission. As the NACKs are sent on the same resource, the serving eNB will receive the NACK with an SFN gain when more than one UE transmits the ACK. When the serving eNB receives a NACK, the serving eNB retransmits the multicast/broadcast data transmission packet. If there is DTX on the ACK/NACK resource (i.e., no NACK is received), the serving eNB assumes that all the UEs successfully decoded the multicast/broadcast data transmission packet. The ACK/NACK procedure reduces UL ACK/NACK overhead, as only a single ACK/NACK resource is used per group. Further, NACKs have a SFN gain from multiple users, leading into enhanced ACK/NACK detection.
The ACK/NACK procedure provided supra provides for a more efficient ACK/NACK resource utilization, but with a less efficient retransmission, as a NACK from any UEs in a group with respect to a particular packet results in a retransmission of that particular packet to all the UEs in the group. Alternatively, the serving eNB may utilize network coding ARQ (NC-ARQ) during retransmissions. Accordingly, the retransmission packet may be a function of multiple packets. For example, assume the serving eNB transmits first and second multicast/broadcast data transmission packets, and a first UE is unable to decode successfully the first multicast/broadcast data transmission packet, and the second UE is unable to decode successfully the second multicast/broadcast data transmission packet. The first UE will send a NACK to indicate that the UE was unable to decode the first multicast/broadcast data transmission packet, and the second UE will send a NACK to indicate that the UE was unable to decode the second multicast/broadcast data transmission packet. The serving eNB may combine the first and second multicast/broadcast data transmission packets (e.g., through XOR), and send the combined multicast/broadcast data transmission packet to the first and second UEs. Assume each of the first and second UEs are able to decode the combined multicast/broadcast data transmission packet. The first UE may obtain the first multicast/broadcast data transmission packet based on the second multicast/broadcast data transmission packet and the combined multicast/broadcast data transmission packet, and the second UE may obtain the second multicast/broadcast data transmission packet based on the first multicast/broadcast data transmission packet and the combined multicast/broadcast data transmission packet. As demonstrated in the example, NC-ARQ provides for a more efficient eNB retransmission, but with a less efficient ACK/NACK resource utilization. Utilizing NC-ARQ allows the UE to be aware of ACK/NACK status from each individual UE on an RLC level.
ACK and CQI may be transmitted simultaneously. When a UE in the group needs to transmit ACK and CQI simultaneously, modulated RS may be used for normal CP and joint coding may be used for extended CP. UEs that transmit ACK/NACK and CQI simultaneously do not use a PUCCH format 1 message. With group NACK, UEs within the group send NACK on the same resource if they are not scheduled to send CQI. Otherwise if UEs are scheduled to send CQI, the UEs send individual regular ACK/NACK together with CQI on a corresponding CQI resource. The serving eNB detects ACK/NACK from those UEs that are scheduled to send CQI at the same time. Retransmission depends on group NACK detection in addition to individual ACK/NACK on CQI.
As discussed supra, when UEs are in an RRC connected state, the UEs feedback CQI, and when the receiving type is connected or hybrid, the serving eNB may take into account the received CQI when scheduling the group transmission. For example, the serving eNB may send the multicast/broadcast data transmission based on the worst CQI. In one configuration, UEs need not provide CQI feedback if the CQI is greater than a CQI threshold. In such a configuration, if the serving eNB does not receive CQI feedback, the serving eNB may send the multicast/broadcast data transmission based on an MCS corresponding to the CQI threshold, and if the serving eNB receives CQI feedback, the serving eNB may send the multicast/broadcast data transmission based on the worst CQI feedback. Based on previous CQI feedback and/or a measurement report, a serving eNB may reconfigure UEs with different CQI feedback configurations (e.g., CQI feedback periods). A serving eNB may configure high geometry UEs (i.e., UEs with high signal quality, smaller path loss) to provide CQI feedback less often compared to low geometry UEs (i.e., UEs with a low signal quality, higher path loss). With individual ACK/NACK feedback, the serving eNB can schedule UEs with NACK feedback to transmit CQI and UEs without NACK feedback not to transmit CQI. Multiple UEs may be scheduled for CQI transmissions on the same resource. UEs that fail to decode may transmit CQI and/or UEs that have a CQI lower than the CQI threshold may transmit CQI. UEs may receive the CQI threshold from an eNB in the PDCCH or in an L3 message, such as through RRC signaling.
All UEs within a group bearer can be configured with rank 1 transmissions in which the UEs do not need to send rank information (RI). When multiple UEs are configured in the group bearer, the serving eNB may configure the UEs with a transmit diversity (TxD) mode. In the TxD mode, UEs may use a space-frequency block code (SFBC) with two eNB transmit antennas or SFBC+frequency switched transmit diversity (FSTD) with four eNB transmit antennas to compute CQI feedback. In TxD mode, UEs need not send precoding matrix indicator (PMI) feedback. A serving eNB may schedule (transmit to) UEs using MU-MIMO mode. For MU-MIMO, a UE may compute CQI and PMI and send the CQI/PMI to the serving eNB. ACK/NACK feedback may be according to regular unicast procedure. A UE can further report CQI based on TxD in case the serving eNB cannot pair the UEs in MU-MIMO mode.
With respect to DRX, UEs follow a group DRX configuration when the group bearer is activated. A serving eNB may schedule regular unicast traffic as well as group traffic in the On Duration of the group DRX configuration. PDCCH load may be increased, as the serving eNB may serve more UEs in the On Duration given that all UEs within the same group follow the group DRX configuration. When a group bearer is deactivated, UEs may follow a non-group DRX configuration if configured.
The paging message may further include a group identifier. The UE may subsequently receive group bearer parameters if the UE is associated with the group identifier. The paging message may further include a G-RNTI. The UE may descramble the received group bearer parameters (e.g., received in a PDSCH) based on the G-RNTI. The group bearer parameters may include at least one of a bearer identifier, the group identifier, the G-RNTI, a list of target UEs, an RLC/PDCP configuration, a QoS profile, an IP address, and the type of the group bearer. The group bearer parameters may include a group DRX configuration. The UE may receive the multicast/broadcast data transmission based on the group DRX configuration when the group bearer is activated.
In step 3406, the UE may receive a multicast/broadcast data transmission packet through the group bearer. In step 3408, the UE may send ACK/NACK based on a received ACK/NACK configuration and may send CQI based on a received CQI configuration. In one configuration, the UE attempts to decode the multicast/broadcast data transmission packet, sends a NACK when unable to decode the multicast/broadcast data transmission packet, and refrains from sending an ACK when able to decode the multicast/broadcast data transmission packet. The NACK may be sent in a PUCCH format 1 message. When the UE sends a NACK in a PUCCH format 1 message, the UE is not scheduled to transmit CQI feedback simultaneously with the NACK. The NACK may be sent in a same resource shared by other UEs. The resource may be associated with a PDCCH used for scheduling the multicast/broadcast data transmission.
Upon determining the type of the group bearer, a UE determines whether to remain in an RRC idle mode, change from an RRC idle mode to an RRC connected mode, remain in an RRC connected mode, or change from an RRC connected mode to an RRC idle mode. When the type of the group bearer is hybrid or connected, and the UE determines to provide CQI feedback, the UE determines to remain in or to change to the RRC connected mode. In one configuration, the UE receives a CQI feedback configuration. The CQI feedback configuration may be based on previously provided CQI feedback or a measurement report. The UE sends CQI feedback based on the CQI feedback configuration. In one configuration, the UE receives a multicast/broadcast data transmission packet through the group bearer. The UE attempts to decode the multicast/broadcast data transmission packet, sends CQI feedback when unable to decode the multicast/broadcast data transmission packet, and refrains from sending the CQI feedback when able to decode the multicast/broadcast data transmission packet. In one configuration, the UE determines CQI feedback, sends the CQI feedback when the CQI feedback is less than a CQI threshold, and refrains from sending the CQI feedback when the CQI feedback is greater than the CQI threshold. The UE may receive the CQI threshold through one of a PDCCH or a layer 3 message. The UE may receive the multicast/broadcast data transmission from an eNB, send a NACK upon unsuccessfully decoding the received multicast/broadcast data transmission, and receive a retransmission of the multicast/broadcast data transmission based on NC-ARQ. The UE may receive a configuration to receive the multicast/broadcast data transmission through rank 1 transmissions from an eNB. The UE may determine CQI feedback based on one of an SFBC diversity scheme, or an SFBC and an FSTD diversity scheme, and send the CQI to the eNB. In one configuration, the UE receives a configuration to receive the multicast/broadcast data transmission through MU-MIMO from an eNB, determines CQI feedback and a PMI, and sends the determined CQI and PMI to the eNB.
The apparatus may include additional modules that perform each of the steps of the algorithm in the aforementioned flow chart of
The processing system 3614 may be coupled to a transceiver 3610. The transceiver 3610 is coupled to one or more antennas 3620. The transceiver 3610 provides a means for communicating with various other apparatus over a transmission medium. The transceiver 3610 receives a signal from the one or more antennas 3620, extracts information from the received signal, and provides the extracted information to the processing system 3614. In addition, the transceiver 3610 receives information from the processing system 3614, and based on the received information, generates a signal to be applied to the one or more antennas 3620. The processing system 3614 includes a processor 3604 coupled to a computer-readable medium 3606. The processor 3604 is responsible for general processing, including the execution of software stored on the computer-readable medium 3606. The software, when executed by the processor 3604, causes the processing system 3614 to perform the various functions described supra for any particular apparatus. The computer-readable medium 3606 may also be used for storing data that is manipulated by the processor 3604 when executing software. The processing system further includes at least one of the modules 3510, 3512, 3514, 3516. The modules may be software modules running in the processor 3604, resident/stored in the computer readable medium 3606, one or more hardware modules coupled to the processor 3604, or some combination thereof. The processing system 3614 may be a component of the UE 650 and may include the memory 660 and/or at least one of the TX processor 668, the RX processor 656, and the controller/processor 659.
In one configuration, the apparatus 3502/3502′ receives a multicast/broadcast data transmission via a group bearer. The apparatus may be a UE. The UE includes means for receiving a paging message including a type of the group bearer, and means for determining whether to remain in or change to an RRC idle mode or an RRC connected mode based on the type of the group bearer received in the paging message. The paging message may further include a group identifier, and the UE may further include means for receiving group bearer parameters if the UE is associated with the group identifier. The paging message may further include a G-RNTI, and the UE may further include means for descrambling the received group bearer parameters based on the G-RNTI. The group bearer parameters may include a group DRX configuration, and the UE may further include means for receiving the multicast/broadcast data transmission based on the group DRX configuration when the group bearer is activated. The UE may further include means for receiving a multicast/broadcast data transmission packet through the group bearer, means for attempting to decode the multicast/broadcast data transmission packet, means for sending a NACK when unable to decode the multicast/broadcast data transmission packet, and means for refraining from sending an ACK when able to decode the multicast/broadcast data transmission packet. The type of the group bearer may be hybrid or connected, and the UE may further include means for determining to remain in or to change to the RRC connected mode. The UE may further include means for receiving a CQI feedback configuration. The CQI feedback configuration may be based on previously provided CQI feedback or a measurement report. The UE may further include means for sending CQI feedback based on the CQI feedback configuration. The UE may further include means for receiving a multicast/broadcast data transmission packet, means for attempting to decode the multicast/broadcast data transmission packet, means for sending CQI feedback when unable to decode the multicast/broadcast data transmission packet, and means for refraining from sending the CQI feedback when able to decode the multicast/broadcast data transmission packet. The UE may further include means for determining CQI feedback, means for sending the CQI feedback when the CQI feedback is less than a CQI threshold, and means for refraining from sending the CQI feedback when the CQI feedback is greater than the CQI threshold. The UE may further include means for receiving the CQI threshold through one of a PDCCH or a layer 3 message. The UE may further include means for receiving the multicast/broadcast data transmission from an eNB, means for sending a NACK upon unsuccessfully decoding the received multicast/broadcast data transmission, and means for receiving a retransmission of the multicast/broadcast data transmission based on NC-ARQ. The UE may further include means for receiving a configuration to receive the multicast/broadcast data transmission through rank 1 transmissions from an eNB. The UE may further include means for determining CQI feedback based on one of an SFBC diversity scheme, or an SFBC and an FSTD diversity scheme, and means for sending the CQI to the eNB. The UE may further include means for receiving a configuration to receive the multicast/broadcast data transmission through MU-MIMO from an eNB, means for determining CQI feedback and a PMI, and means for sending the determined CQI and PMI to the eNB.
The aforementioned means may be one or more of the aforementioned modules of the apparatus 3502 and/or the processing system 3614 of the apparatus 3502′ configured to perform the functions recited by the aforementioned means. As described supra, the processing system 3614 may include the TX Processor 668, the RX Processor 656, and the controller/processor 659. As such, in one configuration, the aforementioned means may be the TX Processor 668, the RX Processor 656, and the controller/processor 659 configured to perform the functions recited by the aforementioned means.
In step 3706, the eNB may send an ACK/NACK configuration to the set of UEs for sending ACK/NACK and send a CQI configuration to the set of UEs for sending CQI feedback. In step 3708, the eNB may receive CQI feedback and adjust/determine an MCS for the multicast/broadcast data transmission based on the adjusted MCS. In step 3710, the eNB may send the multicast/broadcast data transmission packet to the set of UEs through the group bearer. In step 3712, the eNB may retransmit the multicast/broadcast data transmission based on a received NACK. In one configuration, the eNB sends a multicast/broadcast data transmission packet to the set of UEs through the group bearer and receives a NACK from each UE in the set of UEs that is unable to decode the multicast/broadcast data transmission packet. In such a configuration, ACKs are not received from UEs in the set of UEs that are able to decode the multicast/broadcast data transmission packet. Each NACK may be received in a PUCCH format 1 message. Each NACK may be received in a same resource shared by each UE in the set of UEs. The resource may be associated with a PDCCH used for scheduling the multicast/broadcast data transmission.
When UEs in the set of UEs send CQI, the eNB may determine the type of the group bearer to be hybrid or connected. The eNB may receive CQI feedback from UEs in the set of UEs that are in an RRC connected mode. In one configuration, the eNB determines an MCS based on the received CQI, and transmits the multicast/broadcast data transmission based on the determined MCS. The eNB may determine the MCS based on a lowest received CQI. In one configuration, the eNB determines a CQI feedback configuration for each UE in the set of UEs based on at least one of CQI feedback or measurement reports received from the UEs, sends the determined CQI feedback configuration to each UE, and receives CQI feedback from each UE in the set of UEs based on the provided CQI feedback configuration. In one configuration, the eNB sends a multicast/broadcast data transmission packet, and configures UEs in the set of UEs to send the CQI feedback when unable to decode the multicast/broadcast data transmission packet and to refrain from sending the CQI feedback when able to decode the multicast/broadcast data transmission packet. In one configuration, the eNB sends a CQI threshold to UEs in the set of UEs, sends a multicast/broadcast data transmission packet, and configures UEs in the set of UEs to send the CQI feedback when CQI is less than the CQI threshold and to refrain from sending the CQI feedback when CQI is greater than the CQI threshold. The eNB may check for a NACK on a CQI resource and an ACK/NACK resource. The ACK/NACK resource is associated with a PDCCH used for scheduling the multicast/broadcast data transmission.
The eNB may send the multicast/broadcast data transmission, receive a NACK with respect to the multicast/broadcast data transmission, and retransmit the multicast/broadcast data transmission based on NC-ARQ. The eNB may send the multicast/broadcast data transmission through a rank 1 transmission. The eNB may send the multicast/broadcast data transmission by utilizing one of an SFBC diversity scheme, or an SFBC and an FSTD diversity scheme. The eNB may send the multicast/broadcast data transmission to the set of UEs through MU-MIMO.
The apparatus may include additional modules that perform each of the steps of the algorithm in the aforementioned flow chart of
The processing system 3914 may be coupled to a transceiver 3910. The transceiver 3910 is coupled to one or more antennas 3920. The transceiver 3910 provides a means for communicating with various other apparatus over a transmission medium. The transceiver 3910 receives a signal from the one or more antennas 3920, extracts information from the received signal, and provides the extracted information to the processing system 3914. In addition, the transceiver 3910 receives information from the processing system 3914, and based on the received information, generates a signal to be applied to the one or more antennas 3920. The processing system 3914 includes a processor 3904 coupled to a computer-readable medium 3906. The processor 3904 is responsible for general processing, including the execution of software stored on the computer-readable medium 3906. The software, when executed by the processor 3904, causes the processing system 3914 to perform the various functions described supra for any particular apparatus. The computer-readable medium 3906 may also be used for storing data that is manipulated by the processor 3904 when executing software. The processing system further includes at least one of the modules 3810, 3812, 3814, 3816. The modules may be software modules running in the processor 3904, resident/stored in the computer readable medium 3906, one or more hardware modules coupled to the processor 3904, or some combination thereof. The processing system 3914 may be a component of the eNB 610 and may include the memory 676 and/or at least one of the TX processor 616, the RX processor 670, and the controller/processor 675.
In one configuration, the apparatus 3802/3802′ provides a multicast/broadcast data transmission via a group bearer. The apparatus may be an eNB. The eNB includes means for determining a type of the group bearer, and means for sending a paging message including the type of the group bearer to a set of UEs. The eNB may further include means for determining at least one of a type of the multicast/broadcast data transmission, an importance of the multicast/broadcast data transmission, or a number of UEs in the set of UEs. The type of the group bearer may be determined based on the determined at least one of the type of the multicast/broadcast data transmission, the importance of the multicast/broadcast data transmission, or the number of UEs in the set of UEs. The paging message may further include a group identifier associated with the set of UEs. The eNB may further include means for sending group bearer parameters to the set of UEs. The paging message may further include a G-RNTI. The eNB may further include means for scrambling the group bearer parameters based on the G-RNTI. The group bearer parameters may include a group DRX configuration. The eNB may further include means for transmitting the multicast/broadcast data transmission to the set of UEs based on the group DRX configuration when the group bearer is activated. The eNB may further include means for sending a multicast/broadcast data transmission packet to the set of UEs through the group bearer, and means for receiving a NACK from each UE in the set of UEs that is unable to decode the multicast/broadcast data transmission packet. The ACKs may not be received from UEs in the set of UEs that are able to decode the multicast/broadcast data transmission packet. The type of the group bearer may be determined to be hybrid or connected, and the eNB may further include means for receiving CQI feedback from UEs in the set of UEs that are in an RRC connected mode. The eNB may further include means for determining an MCS based on the received CQI, and means for transmitting the multicast/broadcast data transmission based on the determined MCS. The eNB may further include means for determining a CQI feedback configuration for each UE in the set of UEs based on at least one of CQI feedback or measurement reports received from the UE, means for sending the determined CQI feedback configuration to each UE, and means for receiving CQI feedback from each UE in the set of UEs based on the provided CQI feedback configuration. The eNB may further include means for sending a multicast/broadcast data transmission packet, and means for configuring UEs in the set of UEs to send the CQI feedback when unable to decode the multicast/broadcast data transmission packet and to refrain from sending the CQI feedback when able to decode the multicast/broadcast data transmission packet. The eNB may further include means for sending a CQI threshold to UEs in the set of UEs, means for sending a multicast/broadcast data transmission packet, and means for configuring UEs in the set of UEs to send the CQI feedback when CQI is less than the CQI threshold and to refrain from sending the CQI feedback when CQI is greater than the CQI threshold. The eNB may further include means for checking for a NACK on a CQI resource and an ACK/NACK resource. The ACK/NACK resource may be associated with a PDCCH used for scheduling the multicast/broadcast data transmission. The eNB may further include means for sending the multicast/broadcast data transmission, means for receiving a NACK with respect to the multicast/broadcast data transmission, and means for retransmitting the multicast/broadcast data transmission based on NC-ARQ. The eNB may further include means for sending the multicast/broadcast data transmission through a rank 1 transmission. The eNB may further include means for sending the multicast/broadcast data transmission to the set of UEs through MU-MIMO.
The aforementioned means may be one or more of the aforementioned modules of the apparatus 3802 and/or the processing system 3914 of the apparatus 3802′ configured to perform the functions recited by the aforementioned means. As described supra, the processing system 3914 may include the TX Processor 616, the RX Processor 670, and the controller/processor 675. As such, in one configuration, the aforementioned means may be the TX Processor 616, the RX Processor 670, and the controller/processor 675 configured to perform the functions recited by the aforementioned means.
For a particular PTT/PTX communication to a set of UEs, multiple different bearers may be established by the network. For example, assume a set of target UEs includes a first subset in the coverage of a first eNB, a second subset in the coverage of a second eNB, and a third subset in the coverage of a third eNB. The first eNB establishes one of a unicast bearer, a group bearer, or an MBMS bearer, the second eNB establishes one of a unicast bearer, a group bearer, or an MBMS bearer, and the third eNB establishes one of a unicast bearer, a group bearer, or an MBMS bearer. The first, second, and third eNBs may establish different types of bearers based on bearer capabilities of UEs in the corresponding subset of UEs, a number of UEs in the corresponding subset of UEs, whether file repair is needed for the PTT/PTX communication, a type of the PTT/PTX communication, or an importance of the PTT/PTX communication.
The apparatus may include additional modules that perform each of the steps of the algorithm in the aforementioned flow chart of
The processing system 4214 may be coupled to a transceiver 4210. The transceiver 4210 is coupled to one or more antennas 4220. The transceiver 4210 provides a means for communicating with various other apparatus over a transmission medium. The transceiver 4210 receives a signal from the one or more antennas 4220, extracts information from the received signal, and provides the extracted information to the processing system 4214. In addition, the transceiver 4210 receives information from the processing system 4214, and based on the received information, generates a signal to be applied to the one or more antennas 4220. The processing system 4214 includes a processor 4204 coupled to a computer-readable medium 4206. The processor 4204 is responsible for general processing, including the execution of software stored on the computer-readable medium 4206. The software, when executed by the processor 4204, causes the processing system 4214 to perform the various functions described supra for any particular apparatus. The computer-readable medium 4206 may also be used for storing data that is manipulated by the processor 4204 when executing software. The processing system further includes at least one of the modules 4110, 4112, 4114, 4116. The modules may be software modules running in the processor 4204, resident/stored in the computer readable medium 4206, one or more hardware modules coupled to the processor 4204, or some combination thereof. The processing system 4214 may be a component of the eNB 610 and may include the memory 676 and/or at least one of the TX processor 616, the RX processor 670, and the controller/processor 675.
In one configuration, the apparatus 4102/4102′ is for PTT/PTX communication and includes means for receiving a PTT/PTX message for a set of UEs, means for establishing one of a unicast bearer, a group bearer, or an MBMS bearer based on at least one of the PTT/PTX message or the set of UEs, and means for sending the PTT/PTX message through the established bearer to the set of UEs. The apparatus may further include means for determining whether to establish the unicast bearer, the group bearer, or the MBMS bearer based on at least one of bearer capabilities of UEs in the set of UEs, a number of UEs in the set of UEs, whether file repair is needed for the PTT/PTX communication, a type of the PTT/PTX communication, or an importance of the PTT/PTX communication.
The aforementioned means may be one or more of the aforementioned modules of the apparatus 4102 and/or the processing system 4214 of the apparatus 4102′ configured to perform the functions recited by the aforementioned means. As described supra, the processing system 4214 may include the TX Processor 616, the RX Processor 670, and the controller/processor 675. As such, in one configuration, the aforementioned means may be the TX Processor 616, the RX Processor 670, and the controller/processor 675 configured to perform the functions recited by the aforementioned means.
It is understood that the specific order or hierarchy of steps in the processes disclosed is an illustration of exemplary approaches. Based upon design preferences, it is understood that the specific order or hierarchy of steps in the processes may be rearranged. Further, some steps may be combined or omitted. The accompanying method claims present elements of the various steps in a sample order, and are not meant to be limited to the specific order or hierarchy presented.
The previous description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown herein, but is to be accorded the full scope consistent with the language claims, wherein reference to an element in the singular is not intended to mean “one and only one” unless specifically so stated, but rather “one or more.” Unless specifically stated otherwise, the term “some” refers to one or more. Combinations such as “at least one of A, B, or C,” “at least one of A, B, and C,” and “A, B, C, or any combination thereof” include any combination of A, B, and/or C, and may include multiples of A, multiples of B, or multiples of C. Specifically, combinations such as “at least one of A, B, or C,” “at least one of A, B, and C,” and “A, B, C, or any combination thereof” may be A only, B only, C only, A and B, A and C, B and C, or A and B and C, where any such combinations may contain one or more member or members of A, B, or C. All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. No claim element is to be construed as a means plus function unless the element is expressly recited using the phrase “means for.”
This application claims the benefit of PCT Application No. PCT/CN2013/074360, entitled “MBMS BEARER ENHANCEMENTS FOR PUSH TO TALK OR PUSH TO EVERYTHING VIA EMBMS” and filed on Apr. 18, 2013, which is expressly incorporated by reference herein in its entirety.
Filing Document | Filing Date | Country | Kind |
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PCT/CN2013/075646 | 5/15/2013 | WO | 00 |