Patent Application
20200008189
The present disclosure relates generally to communication systems. More specifically, the present disclosure relates to Physical Uplink Control Channel (PUCCH) design for 5th generation (5G) new radio (NR).
Wireless communication devices have become smaller and more powerful in order to meet consumer needs and to improve portability and convenience. Consumers have become dependent upon wireless communication devices and have come to expect reliable service, expanded areas of coverage, and increased functionality. A wireless communication system may provide communication for a number of wireless communication devices, each of which may be serviced by a base station. A base station may be a device that communicates with wireless communication devices.
In 5G NR, different services can be supported with different Quality of Service (QoS) requirements, e.g. reliability and delay tolerance. For example, enhanced Mobile Broadband (eMBB) is targeted for high data rates, and Ultra-Reliable Low Latency Communications (URLLC) is for ultra-reliability and low latency. To provide ultra-reliability for URLLC traffic, the PUCCH for Uplink Control Information (UCI) feedback should also be enhanced to the same reliability level as the data for URLLC. That is, for URLLC Physical Downlink Shared Channel (PDSCH) transmissions, the Hybrid Automatic Repeat Request Acknowledgement (HARQ-ACK) feedback of a URLLC Downlink (DL) data should have the same reliability requirements as the URLCC data transmission itself.
The current NR PUCCH design is targeted for a Acknowledge (ACK) miss detection probability of 10−2, and Negative ACK (NACK) to ACK error probability of 10−3. Therefore, it would be advantageous if enhancements could be specified to increase the PUCCH reliability for HARQ-ACK feedback of URLLC traffic.
Disclosed herein are systems and methods for increasing reliability in Ultra-Reliable Low Latency Communications (URLLC) Physical Uplink Control Channels (PUCCHs). Due to the ultra-low latency requirements, the PUCCH format 0, i.e. the short PUCCH with up to 2 bits of Uplink Control Information (UCI), is more suitable for URLLC data Hybrid Automatic Repeat Request Acknowledge (HARQ-ACK) feedback. In New Radio (NR), PUCCH format 0 is a short PUCCH with 1 or 2 symbols, and is designed for feedback of up to 2 UCI bits. To reduce the error probability of PUCCH format 0, several methods are presented:
The above-mentioned methods can be configured independently or jointly. To provide ultra-reliability for URLLC traffic, the PUCCH for UCI feedback should also be enhanced to the same reliability level as the data for URLLC. Due to the ultra-low latency requirements, the PUCCH format 0, i.e. the short PUCCH with up to 2 bits of UCI, is more suitable for URLLC data HARQ-ACK feedback.
Accordingly, A mobile station is provided with receiving circuitry configured to receive a Radio Resource Control (RRC) message with a first set of transmission power parameters and a second set of transmission power parameters. Transmitting circuitry is configured to transmit UCI using a PUCCH format 0, with the UCI being transmitted based upon either the first set of transmission power parameters or the second set of transmission power parameters. The selection of which parameter is responsive to the type of Radio Network Temporary Identifier (RNTI) used for scheduling physical downline shared channel (PDSCH) communications. The number of bits supported for the UCI using the PUCCH format 0 is either 1 bit or 2 bits and a low-Peak to Average Power Ratio (low-PAPR) sequence is used for the PUCCH format 0.
The mobile station transmitting circuitry transmits using the first set of transmission power parameters for the UCI when a Cell-Radio Network Temporary Identifier (C-RNTI) is used for scheduling the PDSCH. Alternatively, the transmitting circuitry transmits using the second set of transmission power parameters for the UCI when a RNTI, different from a C-RNTI, is used for scheduling of the PDSCH.
Also provided is a base station with transmitting circuitry configured to transmit a RRC message with a first set of transmission power parameters and a second set of transmission power parameters. Receiving circuitry is configured to receive UCI using the PUCCH format 0, with the UCI being received with a power based upon either the first set of transmission power parameters or the second set of transmission power parameters. The selection of which parameter is responsive to the type of RNTI used for the PDSCH communications. The number of bits supported for the UCI using the PUCCH format 0 is either 1 bit or 2 bits, and a low-PAPR sequence is also used for the PUCCH format 0. The receiving circuitry receives the UCI using the first set of transmission power parameters when a C-RNTI is used for scheduling of the PDSCH, or the receiving circuitry receives the UCI using the second set of transmission power parameters when a RNTI, different from a C-RNTI, is used for scheduling of the PDSCH.
In another aspect, the mobile station includes receiving circuitry configured to receive a RRC message including first information used for configuring a number of repetitions in a time domain for the PUCCH format 0. Transmitting circuitry is configured to transmit UCI using the PUCCH format 0. As above, either 1 bit or 2 bits is supported for the UCI using the PUCCH format 0, and a low-PAPR sequence is also used for the PUCCH format 0. If a first number of repetitions has been previously configured, the transmitting circuitry repeatedly transmits the UCI using the PUCCH format 0 in continuous symbols based on the first number of repetitions.
The mobile station the receiving circuitry may also, or alternatively receive a second information used to enable frequency hopping in a frequency domain for the PUCCH format 0. If hopping in the frequency is enabled, the transmitting circuitry transmits the UCI using the PUCCH format 0 with hopping in the frequency domain, where the number of repetitions in the time domain is applied per hop in the frequency domain.
In one aspect of the base station, transmitting circuitry is configured to transmit a RRC message including first information used for configuring a number of repetitions in a time domain for the PUCCH format 0. The receiving circuitry is configured to receive UCI using the PUCCH format 0, where either 1 bit or 2 bits is supported for the UCI using the PUCCH format 0, and a low-PAPR sequence is also used for the PUCCH format 0. If a first number of repetitions has been previously configured, the receiving circuitry repeatedly receives the UCI using the PUCCH format 0 in continuous symbols based on the first number of repetitions.
Alternatively or in addition, the base station transmitting circuitry is configured to transmit a RRC message including second information used for enabling hopping in a frequency domain for the PUCCH format 0. Then, the receiving circuitry, if hopping in the frequency is enabled, receives the UCI using the PUCCH format 0 with hopping in the frequency domain, where the number of repetitions in the time domain is applied per hop in the frequency domain.
Additional details of the above-described communications network UE and methods of improving the reliability of URLLC PUCCH format 0 communications are provided below.
The 3rd Generation Partnership Project, also referred to as “3GPP,” is a collaboration agreement that aims to define globally applicable technical specifications and technical reports for third and fourth generation wireless communication systems. The 3GPP may define specifications for next generation mobile networks, systems, and devices.
3GPP Long Term Evolution (LTE) is the name given to a project to improve the Universal Mobile Telecommunications System (UMTS) mobile phone or device standard to cope with future requirements. In one aspect, UMTS has been modified to provide support and specification for the Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN).
At least some aspects of the systems and methods disclosed herein may be described in relation to the 3GPP LTE, LTE-Advanced (LTE-A) and other standards (e.g., 3GPP Releases 8, 9, 10, 11 and/or 12). However, the scope of the present disclosure should not be limited in this regard. At least some aspects of the systems and methods disclosed herein may be utilized in other types of wireless communication systems.
A wireless communication device may be an electronic device used to communicate voice and/or data to a base station, which in turn may communicate with a network of devices (e.g., public switched telephone network (PSTN), the Internet, etc.). In describing systems and methods herein, a wireless communication device may alternatively be referred to as a mobile station, a user equipment (UE), an access terminal, a subscriber station, a mobile terminal, a remote station, a user terminal, a terminal, a subscriber unit, a mobile device, etc. Examples of wireless communication devices include cellular phones, smart phones, personal digital assistants (PDAs), laptop computers, netbooks, e-readers, wireless modems, etc. In 3GPP specifications, a wireless communication device is typically referred to as a UE. However, as the scope of the present disclosure should not be limited to the 3GPP standards, the terms “UE” and “wireless communication device” may be used interchangeably herein to mean the more general term “wireless communication device.” A UE may also be more generally referred to as a terminal device.
In 3GPP specifications, a base station is typically referred to as a Node B (3G), an evolved Node B (eNB) or a home enhanced or evolved Node B (HeNB) (4G), or some other similar terminology. As the scope of the disclosure should not be limited to 3GPP standards, the terms “base station,” “Node B,” “eNB,” and “HeNB” may be used interchangeably herein to mean the more general term “base station.” Furthermore, the term “base station” may be used to denote an access point. An access point may be an electronic device that provides access to a network (e.g., Local Area Network (LAN), the Internet, etc.) for wireless communication devices. The term “communication device” may be used to denote both a wireless communication device and/or a base station. An eNB may also be more generally referred to as a base station device.
It should be noted that as used herein, a “cell” may be any communication channel that is specified by standardization or regulatory bodies to be used for International Mobile Telecommunications-Advanced (IMT-Advanced) and all of it or a subset of it may be adopted by 3GPP as licensed bands (e.g., frequency bands) to be used for communication between an eNB and a UE. It should also be noted that in E-UTRA and E-UTRAN overall description, as used herein, a “cell” may be defined as “combination of downlink and optionally uplink resources.” The linking between the carrier frequency of the downlink resources and the carrier frequency of the uplink resources may be indicated in the system information transmitted on the downlink resources.
“Configured cells” are those cells of which the UE is aware and is allowed by an eNB to transmit or receive information. “Configured cell(s)” may be serving cell(s). The UE may receive system information and perform the required measurements on all configured cells. “Configured cell(s)” for a radio connection may consist of a primary cell and/or no, one, or more secondary cell(s). “Activated cells” are those configured cells on which the UE is transmitting and receiving. That is, activated cells are those cells for which the UE monitors the physical downlink control channel (PDCCH) and in the case of a downlink transmission, those cells for which the UE decodes a physical downlink shared channel (PDSCH). “Deactivated cells” are those configured cells that the UE is not monitoring the transmission PDCCH. It should be noted that a “cell” may be described in terms of differing dimensions. For example, a “cell” may have temporal, spatial (e.g., geographical) and frequency characteristics.
Fifth generation (5G) cellular communications (also referred to as “New Radio”, “New Radio Access Technology” or “NR” by 3GPP) envisions the use of time/frequency/space resources to allow for enhanced mobile broadband (eMBB) communication and ultra-reliable low latency communication (URLLC) services, as well as massive machine type communication (mMTC) like services. In order for the services to use the time/frequency/space medium efficiently it would be useful to be able to flexibly schedule services on the medium so that the medium may be used as effectively as possible, given the conflicting needs of URLLC, eMBB, and mMTC. A new radio base station may be referred to as a gNB. A gNB may also be more generally referred to as a base station device.
In 5G NR, at least two different types of uplink control channel (PUCCH) formats may be specified: at least one short PUCCH format and one long PUCCH format. The PUCCH channel is designed to carry uplink control information (UCI). In NR, the long PUCCH format may span over multiple slots, and the PUCCH format of a UE may be configured by a base station.
Various examples of the systems and methods disclosed herein are now described with reference to the figures, where like reference numbers may indicate functionally similar elements. The systems and methods as generally described and illustrated in the figures herein could be arranged and designed in a wide variety of different implementations. Thus, the following more detailed description of several implementations, as represented in the figures, is not intended to limit scope, as claimed, but is merely representative of the systems and methods.
The UE 102 and the gNB 160 may use one or more channels 119, 121 to communicate with each other. For example, a UE 102 may transmit information or data to the gNB 160 using one or more uplink channels 121. Examples of uplink channels 121 include a PUCCH and a PUSCH, etc. The one or more gNBs 160 may also transmit information or data to the one or more UEs 102 using one or more downlink channels 119, for instance. Examples of downlink channels 119 include a PDCCH, a PDSCH, etc. Other kinds of channels may be used.
Each of the one or more UEs 102 may include one or more transceivers 118, one or more demodulators 114, one or more decoders 108, one or more encoders 150, one or more modulators 154, a data buffer 104, and a UE operations module 124. For example, one or more reception and/or transmission paths may be implemented in the UE 102. For convenience, only a single transceiver 118, decoder 108, demodulator 114, encoder 150, and modulator 154 are illustrated in the UE 102, though multiple parallel elements (e.g., transceivers 118, decoders 108, demodulators 114, encoders 150, and modulators 154) may be implemented.
The transceiver 118 may include one or more receivers 120 and one or more transmitters 158. The one or more receivers 120 may receive signals from the gNB 160 using one or more antennas 122a-n. For example, the receiver 120 may receive and downconvert signals to produce one or more received signals 116. The one or more received signals 116 may be provided to a demodulator 114. The one or more transmitters 158 may transmit signals to the gNB 160 using one or more antennas 122a-n. For example, the one or more transmitters 158 may upconvert and transmit one or more modulated signals 156.
The demodulator 114 may demodulate the one or more received signals 116 to produce one or more demodulated signals 112. The one or more demodulated signals 112 may be provided to the decoder 108. The UE 102 may use the decoder 108 to decode signals. The decoder 108 may produce decoded signals 110, which may include a UE-decoded signal 106 (also referred to as a first UE-decoded signal 106). For example, the first UE-decoded signal 106 may comprise received payload data, which may be stored in a data buffer 104. Another signal included in the decoded signals 110 (also referred to as a second UE-decoded signal 110) may comprise overhead data and/or control data. For example, the second UE-decoded signal 110 may provide data that may be used by the UE operations module 124 to perform one or more operations.
In general, the UE operations module 124 may enable the UE 102 to communicate with the one or more gNBs 160. The UE operations module 124 may include one or more of a UE PUCCH module 126. The UE PUCCH module 126 may include an enhanced PUCCH format 0 module 127 to HARQ-ACK modifications and modified messages for 5th generation (5G) new radio (NR) as described herein.
The UE operations module 124 may provide information 148 to the one or more receivers 120. For example, the UE operations module 124 may inform the receiver(s) 120 when to receive retransmissions.
The UE operations module 124 may provide information 138 to the demodulator 114. For example, the UE operations module 124 may inform the demodulator 114 of a modulation pattern anticipated for transmissions from the gNB 160.
The UE operations module 124 may provide information 136 to the decoder 108. For example, the UE operations module 124 may inform the decoder 108 of an anticipated encoding for transmissions from the gNB 160.
The UE operations module 124 may provide information 142 to the encoder 150. The information 142 may include data to be encoded and/or instructions for encoding. For example, the UE operations module 124 may instruct the encoder 150 to encode transmission data 146 and/or other information 142. The other information 142 may include PDSCH hybrid automatic repeat request acknowledgment (HARQ-ACK) information.
The encoder 150 may encode transmission data 146 and/or other information 142 provided by the UE operations module 124. For example, encoding the data 146 and/or other information 142 may involve error detection and/or correction coding, mapping data to space, time, and/or frequency resources for transmission, multiplexing, etc. The encoder 150 may provide encoded data 152 to the modulator 154.
The UE operations module 124 may provide information 144 to the modulator 154. For example, the UE operations module 124 may inform the modulator 154 of a modulation type (e.g., constellation mapping) to be used for transmissions to the gNB 160. The modulator 154 may modulate the encoded data 152 to provide one or more modulated signals 156 to the one or more transmitters 158.
The UE operations module 124 may provide information 140 to the one or more transmitters 158. This information 140 may include instructions for the one or more transmitters 158. For example, the UE operations module 124 may instruct the one or more transmitters 158 when to transmit a signal to the gNB 160. For instance, the one or more transmitters 158 may transmit during a UL subframe. The one or more transmitters 158 may upconvert and transmit the modulated signal(s) 156 to one or more gNBs 160.
Each of the one or more gNBs 160 may include one or more transceivers 176, one or more demodulators 172, one or more decoders 166, one or more encoders 109, one or more modulators 113, a data buffer 162, and a gNB operations module 182. For example, one or more reception and/or transmission paths may be implemented in a gNB 160. For convenience, only a single transceiver 176, decoder 166, demodulator 172, encoder 109, and modulator 113 are illustrated in the gNB 160, though multiple parallel elements (e.g., transceivers 176, decoders 166, demodulators 172, encoders 109, and modulators 113) may be implemented.
The transceiver 176 may include one or more receivers 178 and one or more transmitters 117. The one or more receivers 178 may receive signals from the UE 102 using one or more antennas 180a-n. For example, the receiver 178 may receive and downconvert signals to produce one or more received signals 174. The one or more received signals 174 may be provided to a demodulator 172. The one or more transmitters 117 may transmit signals to the UE 102 using one or more antennas 180a-n. For example, the one or more transmitters 117 may upconvert and transmit one or more modulated signals 115. The one or more receivers 178 may further receive information 190 from gNB operations module 182.
The demodulator 172 may demodulate the one or more received signals 174 to produce one or more demodulated signals 170. The one or more demodulated signals 170 may be provided to the decoder 166. The gNB 160 may use the decoder 166 to decode signals. The decoder 166 may produce one or more decoded signals 164, 168. For example, a first eNB-decoded signal 164 may comprise received payload data, which may be stored in a data buffer 162. A second eNB-decoded signal 168 may comprise overhead data and/or control data. For example, the second eNB-decoded signal 168 may provide data (e.g., PDSCH HARQ-ACK information) that may be used by the gNB operations module 182 to perform one or more operations.
In general, the gNB operations module 182 may enable the gNB 160 to communicate with the one or more UEs 102. The gNB operations module 182 may include one or more of a gNB PUCCH module 194.
The gNB operations module 182 may provide information 188 to the demodulator 172. For example, the gNB operations module 182 may inform the demodulator 172 of a modulation pattern anticipated for transmissions from the UE(s) 102.
The gNB operations module 182 may provide information 186 to the decoder 166. For example, the gNB operations module 182 may inform the decoder 166 of an anticipated encoding for transmissions from the UE(s) 102. The gNB operations module 182 may provide information 101 to the encoder 109. The information 101 may include data to be encoded and/or instructions for encoding. For example, the gNB operations module 182 may instruct the encoder 109 to encode information 101, including transmission data 105.
The encoder 109 may encode transmission data 105 and/or other information included in the information 101 provided by the gNB operations module 182. For example, encoding the data 105 and/or other information included in the information 101 may involve error detection and/or correction coding, mapping data to space, time and/or frequency resources for transmission, multiplexing, etc. The encoder 109 may provide encoded data 111 to the modulator 113. The transmission data 105 may include network data to be relayed to the UE 102.
The gNB operations module 182 may provide information 103 to the modulator 113. This information 103 may include instructions for the modulator 113. For example, the gNB operations module 182 may inform the modulator 113 of a modulation type (e.g., constellation mapping) to be used for transmissions to the UE(s) 102. The modulator 113 may modulate the encoded data 111 to provide one or more modulated signals 115 to the one or more transmitters 117.
The gNB operations module 182 may provide information 192 to the one or more transmitters 117. This information 192 may include instructions for the one or more transmitters 117. For example, the gNB operations module 182 may instruct the one or more transmitters 117 when to (or when not to) transmit a signal to the UE(s) 102. The one or more transmitters 117 may upconvert and transmit the modulated signal(s) 115 to one or more UEs 102.
It should be noted that a DL subframe may be transmitted from the gNB 160 to one or more UEs 102 and that a UL subframe may be transmitted from one or more UEs 102 to the gNB 160. Furthermore, both the gNB 160 and the one or more UEs 102 may transmit data in a standard special subframe.
It should also be noted that one or more of the elements or parts thereof included in the eNB(s) 160 and UE(s) 102 may be implemented in hardware. For example, one or more of these elements or parts thereof may be implemented as a chip, circuitry, or hardware components, etc. It should also be noted that one or more of the functions or methods described herein may be implemented in and/or performed using hardware. For example, one or more of the methods described herein may be implemented in and/or realized using a chipset, an application-specific integrated circuit (ASIC), a large-scale integrated circuit (LSI), or integrated circuit, etc.
The physical uplink control channel for NR may support multiple formats as shown it Table 1. Simultaneous transmission of two PUCCHs with format 0 or 2, or simultaneous transmission of one PUCCH with format 1 or 3 and one PUCCH with format 0 or 2 from a single UE may be supported.
PUCCH format 0 may be a short PUCCH with up to 2 bits of UCI. PUCCH format 0 may use sequences to indicate the UCI values. PUCCH format 0 may occupy a single resource block (RB) by default and 1 or 2 symbols in a slot.
PUCCH format 1 may be a long PUCCH with up to 2 bits of UCI. PUCCH format 1 may use sequences to indicate the UCI values. PUCCH format 1 may occupy a single RB by default and 4-14 symbols in a slot. Time domain orthogonal cover code (OCC) may be applied for PUCCH multiplexing with other UEs.
PUCCH format 2 may be a short PUCCH with more than 2 bits of UCI. PUCCH format 2 may use orthogonal frequency division multiplexing (OFDM) with UCI and DMRS multiplexing in a RB. PUCCH format 2 may occupy 1 or 2 symbols in a slot with configurable RBs to allow different number of UCI payload sizes.
PUCCH format 3 may be a long PUCCH with more than 2 bits of UCI without UE multiplexing. PUCCH format 3 may use DFT-S-OFDM and time division multiplexing (TDM) between UCI and DMRS. PUCCH format 3 may occupy 4-14 symbols in a slot with configurable RBs to allow different number of UCI payload sizes.
PUCCH format 4 may be a long PUCCH with more than 2 bits of UCI with UE multiplexing. PUCCH format 4 may use DFT-S-OFDM and TDM between UCI and DMRS. PUCCH format 3 may occupy 4-14 symbols in a slot. Pre-DFT OCC may be applied for PUCCH multiplexing with other UEs.
Therefore, for PUCCH format configuration, a combination of semi-static configuration and (at least for some types of UCI information) dynamic signaling is used to determine the PUCCH formats and resources both for the long and short PUCCH formats.
PUCCH is used to report important uplink control information (UCI), which includes HARQ-ACK, Scheduling Request (SR), and Channel State Information (CSI) etc. NR release-15 is designed mainly for enhanced mobile broadband (eMBB), several physical uplink control channel (PUCCH) formats are specified for different number of bits, as given below.
Specification section (see Table 1, above):
6.3.2 Physical uplink control channel
6.3.2.1 General
In 5G NR, different services can be supported with different quality of service (QoS) requirements, e.g. reliability and delay tolerance. For example, enhanced Mobile Broadband (eMBB) is targeted for high data rate, and URLLC is for ultra-reliability and low latency. The URLLC traffic may use the same numerology as eMBB service. The URLLC downlink transmission may also use a different subcarrier spacing (SCS) as eMBB DL transmission. For example, the URLLC traffic may use a higher numerology than eMBB service, i.e. the SCS of a URLLC transmission may be larger than that of an eMBB transmission. A larger SCS configuration for URLLC reduces the length of an OFDM symbol, and thus the latency of a transmission and its HARQ-ACK feedback.
The URLLC DL transmission and UL transmission may be configured with the same numerology. The URLLC DL transmission and UL transmission may be configured with the different numerologies. For HARQ-ACK feedback for of DL URLLC transmission, URLLC short PUCCH may use a different numerology from other short PUCCH, and the URLLC PUCCH should have shorter symbol lengths than other short PUCCH or PUSCH transmissions. Systems and methods related to URLLC DL data transmission and the corresponding HARQ-ACK feedback on PUCCH are presented below.
To provide ultra-reliability for URLLC traffic, a different Channel Quality Indicator (CQI) and Modulation and Coding Scheme (MCS) table maybe configured for URLLC with 10−5 error probability. At the same time, the PUCCH for HARQ-ACK feedback of URLLC data can be enhanced at least to the same reliability level as the data for URLLC.
For URLLC traffic, several aspects need to be considered for PUCCH design and PUCCH transmissions. Since URLLC traffic requires ultra-reliability and low latency, the HARQ-ACK for URLLC packet should be supported to provide the required reliability. Furthermore, the HARQ-ACK feedback should be reported immediately after a URLLC transmission. Moreover, the HARQ-ACK feedback should have the same reliability as the URLLC data transmission, i.e. the current PUCCH channel BER requirements of 1% or 0.1% cannot satisfy the URLLC requirements. The HARQ-ACK bit error rate (BER) requirement should be the same or better than the URLLC data channel, i.e. at least 10−5 or 10−6.
The URLLC traffic may share the HARQ-ACK processes with eMBB, however, the number of HARQ-ACK processes for URLLC can be limited, e.g., only 1 or HARQ-ACK processes for URLLC traffic. Thus, the PUCCH format for URLLC DL transmission should also provide ultra-reliability and low latency after a URLLC DL transmission. Only short PUCCH should be used for URLLC HARQ-ACK feedback. The position of short PUCCH can be determined dynamically based on URLLC DL data transmission, e.g. immediately after a URLLC DL transmission with a gap satisfying the processing time requirements. Due to the ultra-low latency requirements, the PUCCH format 0, i.e. the short PUCCH with up to 2 bits of UCI, is more suitable for URLLC data HARQ-ACK feedback.
The NR PUCCH format 0 occupies a single physical resource block (PRB) and uses sequences to indicate up to 2 bits of payload, as shown below
//spec section
The sequence x(n) shall be generated according to
where ru,v(α,δ)(n) is given by clause 6.3.2.2 with mcs depending on the information to be transmitted according to subclause 9.2 of [5, TS 38.213].
The sequence x(n) shall be multiplied with the amplitude scaling factor βPUCCH,0 in order to conform to the transmit power specified in [5, TS 38.213] and mapped in sequence starting with x(0) to resource elements (k,l)p,μ assigned for transmission according to subclause 9.2.1 of [5, TS 38.213] in increasing order of first the index k over the assigned physical resources, and then the index l on antenna port p=2000.
//end of spec section
In one aspect, the enhanced PUCCH format 0 module 127 configures one PRB for the PUCCH resource. The enhanced PUCCH format 0 module 127 transmits the HARQ-ACK message on first antenna port 208 in one PRB of the configured PUCCH resource, and transmits the HARQ-ACK message on second antenna port 212 in a next adjacent one PRB of the configured PUCCH resource. As an alternative, the enhanced PUCCH format 0 module 127 configures more than 1 (k>1) PRBs for the PUCCH resource. Then, the enhanced PUCCH format 0 module 127 transmits the HARQ-ACK message on first antenna port 208 in the k PRBs of the configured PUCCH resource, and transmits the HARQ-ACK message on second antenna port 212 in next adjacent k PRBs of the configured k PRBs PUCCH resource.
In a variation of the above-described UE, the enhanced PUCCH format 0 module 127 configures for transmission a HARQ-ACK message corresponding to the PDSCH using additional reliability enhancement mechanisms. Typically, the enhanced PUCCH format 0 module 127 configures the reliability enhancement mechanism in response to the transceiver receiving a RRC message from a base station, as mentioned above. In addition to the k number of PRBs method described above, the enhanced PUCCH format 0 module 127 may use time domain repetition of a configured PUCCH, transmit diversity using the two antenna ports 208 and 212, or transmit power control. In one aspect, the enhanced PUCCH format 0 module 127 uses the k number of PRBs PUCCH resource mechanism in combination with the transmit diversity mechanism using the two antenna ports 208 and 212.
In the case of time repetition, the enhanced PUCCH format 0 module 127 uses one of the following frequency hopping schemes: frequency hopping at each PUCCH boundary, a single frequency hop for a plurality of PUCCH repetitions, or intra-PUCCH frequency hopping. These frequency hopping schemes are described in more detail below.
In the case of transmit power control, the enhanced PUCCH format 0 module 127 configures the HARQ-ACK message for transmission at an increased power level, as compared to a conventional PUCCH format 0 message, in response to using an enhanced reliability amplitude scaling factor. The enhanced PUCCH transmit power is given by an amplitude scaling factor within more than one configured amplitude scaling factors for a given PUCCH format, with the highest amplitude factor being optionally configurable for enhanced PUCCH format 0. Alternatively stated, the enhanced PUCCH transmit power is given by a separately configured multiplier factor over a configured amplitude scaling factor for a legacy (conventional) PUCCH format.
In one aspect, configuring the first number of PRBs in Step 302 includes configuring k PRBs for the PUCCH resource, where k is an integer greater than or equal to one. In another aspect, configuring the transmission mode in Step 304 includes determining the PUCCH resource used for transmission on each antenna port based on the PUCCH resource configuration.
Returning to
The enhanced PUCCH format 0 module 127 transmits a HARQ-ACK message corresponding to a PDSCH on the PUCCH format 0. Alternatively stated, the enhanced PUCCH format 0 module 127 configures the HARQ-ACK for transmission by the transceiver 206. The HARQ-ACK message may be up to 2 bits in length, and the enhanced PUCCH format 0 module may schedule the PDSCH transmission using Downlink Control Indicator (DCI) scrambled with a Radio Network Temporary Identifier (RNTI) different from C-RNTI.
In one aspect, the enhanced PUCCH format 0 module 127 configures k PRBs for the PUCCH resource, where k is an integer greater than or equal to one. The enhanced PUCCH format 0 module 127 configures l repetitions for the PUCCH resource, where l is an integer greater than or equal to one. Then, the enhanced PUCCH format 0 module 127 transmits the HARQ-ACK message on the PUCCH resource of adjacent k PRBs with l repetitions of continuous symbols in the time domain. For example, if the PUCCH is a 2-symbol PUCCH resource and frequency hopping is enabled, the enhanced PUCCH format 0 module 127 may transmit the HARQ-ACK message on a 2-symbol PUCCH resource with intra-PUCCH frequency hopping.
Alternatively, if the PUCCH is configured with l repetitions and inter-PUCCH frequency hopping is enabled, the enhanced PUCCH format 0 module 127 transmits the HARQ-ACK message on the PUCCH resource with inter-PUCCH frequency hopping. For example, the frequency hopping may performed at each PUCCH resource boundary for the inter-PUCCH frequency hopping. As another example, single frequency hopping is performed in the middle of l PUCCH repetitions for the inter-PUCCH frequency hopping, where the middle is defined by the PUCCH boundary after the ith PUCCH repetition, where i is determined by either floor (l/2) or ceiling(l/2). As a third example, for a 2-symbol PUCCH, the intra-PUCCH frequency hopping may be disabled when inter-PUCCH frequency hopping is enabled.
Further, if a 2-symbol PUCCH is configured with l repetitions, inter-PUCCH frequency hopping may disabled when intra-PUCCH frequency hopping is enabled, and the enhanced PUCCH format 0 module 127 transmits the HARQ-ACK message on the PUCCH resource with frequency hopping within each 2-symbol PUCCH resource.
In another aspect, the enhanced PUCCH format 0 modules 127 configures the first number of PRBs for the PUCCH resource in response to the transceiver receiving a first RRC message from a base station. The enhanced PUCCH format 0 module 127 also configures the number of repetitions of PUCCH resource in the time domain, in response to the transceiver receiving a second RRC message from a base station. As a result, the enhanced PUCCH format 0 module determines frequency hopping enablement in response to the transponder receiving a third RRC message from the base station.
In a different variation of the UE, the enhanced PUCCH format 0 module 127 configures a first reference subcarrier spacing and a second reference subcarrier spacing. Based on the first subcarrier spacing and second subcarrier spacing, the enhanced PUCCH format 0 module 127 determines a number of repetitions, and then transmits a HARQ-ACK message, of up to 2 bits in length, with the determined number of repetitions, corresponding to a PDSCH. As above, the enhanced PUCCH format 0 module 127 may use frequency hopping at each PUCCH boundary, a single frequency hop for a plurality of PUCCH repetitions, and intra-PUCCH frequency hopping.
In one aspect, the enhanced PUCCH format 0 module 127 configures the HARQ-ACK message with the determined number of repetitions using a 1-symbol PUCCH format 0 message repeated k number of times, where k is an integer greater than or equal to 1. Alternatively, the enhanced PUCCH format 0 module 127 may use a 2-symbol PUCCH format 0 message repeated k/2 number of times. As in the first variation, the enhanced PUCCH format 0 module 127 may schedule the PDSCH transmission using DCI scrambled with a RNTI different from C-RNTI.
In one aspect, configuring the first number of PRBs for the PUCCH resource in Step 402 includes configuring k PRBs for the PUCCH resource, where k is an integer greater than or equal to one. Determining the second number of repetitions for the PUCCH resource in Step 404 includes configuring/repetitions for the PUCCH resource, where/is an integer greater than or equal to one. Then, transmitting the HARQ-ACK message in Step 408 includes configuring the HARQ-ACK message corresponding to a PDSCH transmission on the PUCCH resource of adjacent k PRBs with/repetitions of continuous symbols in the time domain.
Optionally, in Step 405 the enhanced PUCCH format 0 module may determine that the PUCCH is a 2-symbol PUCCH resource. Then, determining frequency hopping enablement in Step 406 includes determining that frequency hopping is enabled, and transmitting the HARQ-ACK message in Step 408 includes configuring the HARQ-ACK message on a 2-symbol PUCCH resource with intra-PUCCH frequency hopping.
In another aspect, determining the second number of repetitions for the PUCCH resource in Step 404 includes configuring the PUCCH with/repetitions, and determining frequency hopping enablement in Step 406 includes determining inter-PUCCH frequency hopping is enabled. Then, transmitting the HARQ-ACK message in Step 408 includes configuring the HARQ-ACK message on the PUCCH resource with inter-PUCCH frequency hopping.
Reliability Enhancement for PUCCH Format 0:
For URLLC HARQ-ACK feedback, the reliability of PUCCH format 0 should be enhanced to at least an error rate of 10−5 or 10−6, e.g. the ACK to NACK error probability is 10−5, and NACK to ACK error probability is 10−6. Thus, a new PUCCH format is specified herein for a short PUCCH with ultra-high reliability by extending the PUCCH format 0. Although referred to herein as the enhanced PUCCH format module, the new PUCCH format may alternatively be named as PUCCH format 5, PUCCH format 0_1, advanced PUCCH format 0 (PUCCH format 0a), PUCCH Format 0e, ultra-reliable PUCCH format 0 (PUCCH format 0_r, or format 0_u), etc.
Several techniques have been summarized above that can be used to increase the reliability, at least for PUCCH format 0. Allocating more resources is a straightforward way to increase the PUCCH reliability.
More than One PRBs May be Configured for a Sequence Based PUCCH Format 0
Instead of being limited to 1 PRB, multiple PRBs can be configured for a PUCCH with ultra-reliability. The number of PRB can be configured by higher layer signaling, e.g. RRC configuration, or RRC message. The number of PRBs may be configured within a set of potential values, e.g. {1,2,4,8}, and the indexes of the values can be indicated or configured by the gNB.
In conventional PUCCH format 0, only 1 PRB is occupied. Thus, the sequence transmitted on the PUCCH resource is a length-12 sequence. With more than 1 PRB configured for an enhance PUCCH format 0, the length of the sequence transmitted on the PUCCH resource is determined by the number of PRBs and the number of subcarriers per PRB. The sequence is a low Peak-to-Average Power Ratio (PAPR) sequence defined in Section 5.2.2. of TS 38.211.
Signaling
Time Domain Repetition of PUCCH Format 0
PUCCH format 0 may be configured with 1 or 2 symbols. Besides the number of PRBs, time domain repetition is another way to provide redundancy and reliability for PUCCH. However, too many repetitions on time domain are not desirable due to low latency requirements. Therefore, the numbers of time domain repetitions may be limited to 2, 4, and 8.
When PUCCH repetition is configured for an enhanced PUCCH format 0, the configured PUCCH format 0 may be repeated continuously in time domain from the starting symbol.
Approach 1: Per PUCCH Format 0 Configuration
The frequency hopping can be configured per PUCCH repetition. Thus, the frequency hopping is applied at each PUCCH boundary. The frequency hopping may be configured by an inter-PUCCH hopping parameter by higher layer signaling. For a two-symbol PUCCH, if inter-PUCCH frequency hopping is enabled, intra-PUCCH frequency hopping in each PUCCH is disabled.
Signaling
Approach 2: A Single Hop in the Middle of all PUCCH Repetitions
In this case, only one hop is applied to all PUCCH repetitions in the middle. For example, if the repetition factor is 4, a single hop is applied after the first two PUCCH transmissions. In general, if l repetitions are configured, a single hop is applied after the ith PUCCH transmissions, where i is determined by floor(l/2) or ceil(l/2). The frequency hopping may be configured by an inter-PUCCH hopping parameter by higher layer signaling. For a two symbol PUCCH, if inter-PUCCH frequency hopping is enabled, intra-PUCCH frequency hopping is disabled.
Signaling
Approach 3: Intra-PUCCH Hopping Only for 2-Symbol PUCCH
If inter-PUCCH hopping parameter is not configured by higher layer signaling, for a 2 symbol PUCCH format 0, intra-PUCCH frequency hopping may be configured. In this case, frequency hopping is performed at each symbol boundary.
Especially if the URLLC PUCCH uses a higher SCS setting than eMBB traffic, the symbol duration of URLLC PUCCH becomes shorter, and time domain repetition can be configured. In this case, the enhanced PUCCH format 0 for URLLC may be repeated to fit the symbol duration of the reference numerology defined by eMBB services. This avoids partial symbol overlapping between transmissions with different numerologies.
Here, the first SCS may be configured by using the RRC message. Also, a default value of the first SCS may be defined based on a frequency band(s). For example, the default value of the first SCS may be defined based on the frequency band(s), in advance, by the specifications. For example, if the first SCS is configured by using the RRC message, the UE may use the first SCS configured by using the RRC message, as the reference numerology. Also, if the first SCS is not configured by using the RRC message, the UE may use the default value of the first SCS as the reference numerology. For example, the first SCS may be configured for each of bandwidth parts (e.g., UL bandwidth parts). Also, the first SCS may be configured for each of serving cells. Also, the first SCS may be configured (e.g., separately configured) for each of PUCCH formats (e.g., PUCCH format 0, PUCCH format 1, and/or PUCCH format 3, etc.). Also, the first SCS may be configured (e.g., commonly configured) for more than one PUCCH formats (e.g., PUCCH format 0, PUCCH format 1, and/or PUCCH format 3, etc.).
The second SCS may be configured by using the RRC message. Further, a default value of the second SCS may be defined based on a frequency band(s). For example, the default value of the second SCS may be defined based on the frequency band(s), in advance, by the specifications. For example, if the second SCS is configured by using the RRC message, the UE may use the second SCS configured by using the RRC message. Also, if the second SCS is not configured by using the RRC message, the UE may use the default value of the second SCS. For example, the second SCS may be configured for each of bandwidth parts (e.g., UL bandwidth parts). Also, the second SCS may be configured for each of serving cells. Also, the second SCS may be configured (e.g., separately configured) for each of PUCCH formats (e.g., PUCCH format 0, PUCCH format 1, and/or PUCCH format 3, etc.). Further, the second SCS may be configured (e.g., commonly configured) for more than one PUCCH formats (e.g., PUCCH format 0, PUCCH format 1, and/or PUCCH format 3, etc.).
Thus, as described above, the UE performs, based on the first SCS and the second SCS, PUCCH format 0 repetition.
Transmit Diversity
Transmit diversity (TxD) can also increase the reliability. With TxD, the PUCCH signal is transmitted on two antenna ports, each using a separate PUCCH PRB resource. For HARQ-ACK transmission with sequence based PUCCH format 0, the spatial orthogonal resource transmit diversity (SORTD) scheme may be supported for transmissions with two antenna ports (pϵ[p0, p1]). The UE can use the PUCCH resource for transmission of HARQ-ACK in a slot mapped to antenna port p. For transmission on antenna port p0, the UE shall use a PUCCH resource that is configured or implicitly derived based on Control Channel Element (CCE) indexes of the scheduling DCI. For transmission on antenna port p1, the UE can use the next PUCCH resource after the PUCCH resource used for antenna port p0.
For a PUCCH format 0 configured with 1 PRB and TxD, the PUCCH resource for antenna port p1 may have a starting PRB position that is the next adjacent PRB higher from the starting PRB of the PUCCH resource for antenna port p0. For a PUCCH format 0 configured with k PRBs and TxD, the PUCCH resource for antenna port p1 may have a starting PRB position that is k PRBs next to the starting PRB of the PUCCH resource for antenna port p0.
For example, TxD for the PUCCH format 0 may be configured by using the RRC message. Namely, the gNB may transmit the RRC message including a parameter(s) indicating whether two antenna ports are configured for the PUCCH format 0. For example, the parameter may be configured for each of bandwidth parts (e.g., UL bandwidth parts). Also, the parameter may be configured for each of serving cells. Further, the parameter may be configured (e.g., separately configured) for each of PUCCH formats (e.g., PUCCH format 0, and/or PUCCH format 1, and/or PUCCH format 2, and/or PUCCH format 3, and/or PUCCH format 4, etc.). In addition, the parameter may be configured (e.g., commonly configured) for more than one PUCCH formats (e.g., PUCCH format 0, and/or PUCCH format 1, and/or PUCCH format 2, and/or PUCCH format 3, and/or PUCCH format 4, etc.).
The parameter may be configured (e.g., separately configured) for each of PUCCH resources (e.g., or PUCCH resource sets). Also, the parameter may be configured (e.g., commonly configured) for each of PUCCH resources (or PUCCH resource sets).
Transmit Power Control of Enhanced PUCCH Format 0
Another way to increase the reliability is to increase the transmit power. An enhanced PUCCH format 0 for URLLC may be configured with a higher transmit power than a conventional or “normal” PUCCH format 0.
In one method, a separate amplitude scaling factor βPUCCH,0_1 can be configured and mapped in sequence transmitted on the enhanced PUCCH format 0.
In another method, a new multiplier factor, or a delta value factor δ, can be configured for the enhanced PUCCH format 0, so that the amplitude scaling factor of the sequence transmitted on an enhanced PUCCH format 0 is defined by δβPUCCH,0, where βPUCCH,0 is the amplitude scaling factor configured for normal PUCCH transmission.
In all cases, the actual transmission power is limited by PCMAX,f,c(i), which is the configured UE transmit power defined for carrier f of serving cell c in PUCCH transmission period i.
The PUCCH transmit diversity can be configured to a UE by higher layer signaling. If PUCCH TxD is configured, a delta TxD offset for transmit power control may also be configured. The candidate values of the delta TxD offset may be (−1 dB, 0 dB) as in current LTE specifications.
Configurations of Enhanced PUCCH Format 0 for URLLC
The above-mentioned methods can be configured independently or jointly. For example, to achieve 4 times redundancy compared with normal PUCCH format 0, the enhanced PUCCH format 0 may be configured with:
To support more than one PRB, the PUCCH Format 0_1 resource configuration may have a new field on the number of PRBs. The parameter can be indicated as an integer number, e.g. any number between 1 and 8. The parameter may be indicated as an index of a set of pre-defined values, e.g. {1,2,4,8}. The number of potential values of the set determines the number of bits required to indicate the parameter.
PUCCH-F0_
1-number-of-PRB,
To support PUCCH repetition, several new parameters may be configured by higher layer signaling. In PUCCH-config, a new format format0_1 can be defined, and the interPUCCHFrequencyHopping and the nrofRepetitions can be configured. The number of PUCCH repetitions with the same PUCCH F0 corresponds to L1 parameter ‘PUCCH-F0-number-of-repetitions’. When the field is absent the UE applies the value n1. The set of values for nrofRepetitions is given by {n1, n2, n3, n4}, and may be set as {1,2,4,8}.
If the interPUCCHFrequencyHopping is enabled for PUCCH format 0 with repetitions, the frequencyHopping parameter in PUCCH format 0_1 configuration will be disabled.
The support of PUCCH with two antenna port transmission, i.e. transmit diversity, may be a UE capability. If the UE supports transmit diversity, the UE may be configured by the gNB with two antenna port transmission for enhanced PUCCH formats. Once configured, for transmission on antenna port p0, the UE may use a PUCCH resource that is configured or implicitly derived based on CCE indexes of the scheduling DCI. For transmission on antenna port p1, the UE shall use the next PUCCH resource after the PUCCH resource used for antenna port p0.
The default transmit power of an enhanced PUCCH format 0 may be higher than a conventional or “normal” PUCCH format 0. The UE may be configured by a gNB with a separate amplitude scaling factor βPUCCH,0_1, or be configured with a delta value over the normal PUCCH format 0.
In summary, an enhanced short PUCCH format 0 for URLLC may be configured with a different set of parameters from normal PUCCH format 0 for a UE. The resource and location of short PUCCH may be semi-statically configured, and dynamically transmitted based on DL URLLC reception.
As described above, the UE may transmit by using the enhanced short PUCCH format 0, HARQ-ACK corresponding to URLLC data transmission (e.g., URLLC PDSCH transmission). Here, the UE may transmit by using the conventional or “normal” PUCCH format 0, HARQ-ACK corresponding to data transmission (e.g., PDSCH transmission) other than URLLC data transmission. Namely, the UE may use the enhanced short PUCCH format 0 in a case that HARQ-ACK corresponding to URLLC data transmission is transmitted. Namely, URLLC data transmission (e.g., URLLC PDSCH transmission) may be identified for HARQ-ACK transmission using the enhanced short PUCCH format 0.
For example, the gNB may transmit by using the RRC message, a parameter used for identifying whether or not the PDSCH is corresponding to URLLC data transmission. The parameter may be associated with PDSCH transmission mode(s). Namely, the UE may use the enhanced short PUCCH format 0 to transmit HARQ-ACK corresponding to the PDSCH that is configured with URLLC data transmission. Also, the UE may use the conventional or “normal” PUCCH format 0 to transmit HARQ-ACK corresponding to the PDSCH that is not configured with URLLC data transmission. For example, if two antenna ports (e.g., TxD) are configured (as described above), the UE uses the two antenna ports to transmit HARQ-ACK corresponding to the PDSCH that is configured with URLLC data transmission. Here, even if two antenna ports (e.g., TxD) are configured (as described above), the UE uses one antenna port to transmit HARQ-ACK corresponding to the PDSCH that is not configured with URLLC data transmission.
Also, the PDSCH for URLLC data transmission may be scheduled (e.g., identified) by using DCI (e.g., the DCI format(s)) scrambled with Y-RNTI different from the C-RNTI. Namely, the UE may use the enhanced short PUCCH format 0 to transmit HARQ-ACK corresponding to the PDSCH transmission scheduled by using the DCI scrambled with Y-RNTI. Also, the UE may use the conventional or “normal” PUCCH format 0 to transmit HARQ-ACK corresponding to the PDSCH transmission scheduled by using the DCI scrambled with C-RNTI. For example, if two antenna ports (e.g., TxD) are configured (as described above), the UE uses the two antenna ports to transmit HARQ-ACK corresponding to the PDSCH transmission scheduled by using the DCI scrambled with Y-RNTI. Here, even if two antenna ports (e.g., TxD) are configured (as described above), the UE uses one antenna port to transmit HARQ-ACK corresponding to the PDSCH transmission scheduled by using the DCI scrambled with C-RNTI. Here, the DCI scrambled with Y-RNTI may be detected only in UE-specific search space. And, the DCI scrambled with C-RNTI may be detected only in UE-specific search space and common search space.
Also, a timing(s) (e.g., a position(s) of a slot(s) and/or a symbol(s), a periodicity, and/or an offset value(s)) for the PDSCH for URLLC data transmission may be configured by using the RRC message. Namely, the UE may use the enhanced short PUCCH format 0 to transmit HARQ-ACK corresponding to the PDSCH transmission in the configured timing(s). Also, the UE may use the conventional or “normal” PUCCH format 0 to transmit HARQ-ACK corresponding to the PDSCH transmission in a timing(s) other than the configured timing(s). For example, if two antenna ports (e.g., TxD) are configured (as described above), the UE uses the two antenna ports to transmit HARQ-ACK corresponding to the PDSCH transmission in the configured timing(s). Here, even if two antenna ports (e.g., TxD) are configured (as described above), the UE uses one antenna port to transmit HARQ-ACK corresponding to the PDSCH transmission in the timing(s) other than the configured timing(s).
The PDSCH for URLLC data transmission may be identified by using CQI table(s) (e.g., CQI/MCS table(s)) and/or Block Error Rate (BLER) target(s). For example, the gNB may transmit by using the RRC message, a parameter used for indicating which CQI table(s) is used for CQI calculation. Also, the gNB may transmit by using the RRC message, a parameter used for indicating BLER target that the UE assumes in CQI calculation. Namely, first CQI table and/or first BLER target associated with the PDSCH corresponding to URLLC data transmission may be defined. Also, second CQI table and/or second BLER for the PDSCH corresponding to data transmission other than URLLC data transmission may be defined. And, the UE may use the enhanced short PUCCH format 0 to transmit HARQ-ACK corresponding to the PDSCH transmission associated with the first CQI table and/or the first BLER target. Further, the UE may use the conventional or “normal” PUCCH format 0 to transmit HARQ-ACK corresponding to the PDSCH transmission associated with the second CQI and the second BLER target. For example, if two antenna ports (e.g., TxD) are configured (as described above), the UE uses the two antenna ports to transmit HARQ-ACK corresponding to the PDSCH transmission associated with the first CQI table and/or the first BLER target. Here, even if two antenna ports (e.g., TxD) are configured (as described above), the UE uses one antenna port to transmit HARQ-ACK corresponding to the PDSCH transmission associated with the second CQI table and/or the second BLER target.
The UE may be configured with separate PUCCH resource set for enhanced PUCCH format 0 from the conventional or “normal” PUCCH format.
In
For a PCell, NDLRB is broadcast as a part of system information. For an SCell (including a license assisted access (LAA) SCell), NDLRB is configured by a RRC message dedicated to a UE 102. For PDSCH mapping, the available RE 808 may be the RE 808 whose index l fulfils l≥ldata,start and/or ldata,end≥l in a subframe.
In the downlink, the OFDM access scheme with cyclic prefix (CP) may be employed, which may be also referred to as CP-OFDM. In the downlink, PDCCH, enhanced downlink physical control channel (EPDCCH), PDSCH and the like may be transmitted. A downlink radio frame may consist of multiple pairs of downlink resource blocks (RBs) which is also referred to as physical resource blocks (PRBs). The downlink RB pair is a unit for assigning downlink radio resources, defined by a predetermined bandwidth (RB bandwidth) and a time slot. The downlink RB pair consists of two downlink RBs that are continuous in the time domain.
The downlink RB consists of twelve sub-carriers in the frequency domain and seven (for normal CP) or six (for extended CP) OFDM symbols in time domain. A region defined by one sub-carrier in the frequency domain and one OFDM symbol in the time domain is referred to as a resource element (RE) and is uniquely identified by the index pair (k,l) in a slot, where k and l are indices in the frequency and time domains, respectively. While downlink subframes in one component carrier (CC) are discussed herein, downlink subframes are defined for each CC and downlink subframes are substantially in synchronization with each other among CCs.
In
For a PCell, NULRB is broadcast as a part of system information. For an SCell (including an LAA SCell), NULRB is configured by a RRC message dedicated to a UE 102.
In the uplink, in addition to CP-OFDM, a Single-Carrier Frequency Division Multiple Access (SC-FDMA) access scheme may be employed, which is also referred to as Discrete Fourier Transform-Spreading OFDM (DFT-S-OFDM). In the uplink, PUCCH, PDSCH, physical random access channel (PRACH) and the like may be transmitted. An uplink radio frame may consist of multiple pairs of uplink resource blocks. The uplink RB pair is a unit for assigning uplink radio resources, defined by a predetermined bandwidth (RB bandwidth) and a time slot. The uplink RB pair consists of two uplink RBs that are continuous in the time domain.
The uplink RB may consist of twelve sub-carriers in the frequency domain and seven (for normal CP) or six (for extended CP) OFDM/DFT-S-OFDM symbols in the time domain. A region defined by one sub-carrier in the frequency domain and one OFDM/DFT-S-OFDM symbol in the time domain is referred to as a RE and is uniquely identified by the index pair (k,l) in a slot, where k and l are indices in the frequency and time domains respectively. While uplink subframes in one component carrier (CC) are discussed herein, uplink subframes are defined for each CC.
The sub-slot length may be configured by higher layer signaling. Alternatively, the sub-slot length may be indicated by a physical layer control channel (e.g. by DCI format).
The sub-slot may start at any symbol within a slot unless it collides with a control channel. There could be restrictions of mini-slot length based on restrictions on starting position. For example, the sub-slot with the length of NDLsymb−1 (or NULsymb−1) may start at the second symbol in a slot. The starting position of a sub-slot may be indicated by a physical layer control channel (e.g. by DCI format). Alternatively, the starting position of a sub-slot may be derived from information (e.g. search space index, blind decoding candidate index, frequency, and/or time resource indices, PRB index, a control channel element index, control channel element aggregation level, an antenna port index, etc.) of the physical layer control channel which schedules the data in the concerned sub-slot.
In cases when the sub-slot is configured, a given transport block may be allocated to either a slot, a sub-slot, aggregated sub-slots, or aggregated sub-slot(s) and slot. This unit may also be a unit for HARQ-ACK bit generation.
For a self-contained base DL scheduling timeline, DL control channels are mapped to the initial part of a slot. The DL control channels schedule DL shared channels in the same slot. HARQ-ACKs for the DL shared channels are reported in UL control channels which are mapped at the ending part of the slot. For a self-contained base UL scheduling timeline, DL control channels are mapped to the initial part of a slot. The DL control channels schedule UL shared channels in the same slot. For these cases, the slot may contain DL and UL portions, and there may be a guard period between the DL and UL transmissions.
The use of a self-contained slot may be based upon a configuration of the self-contained slot. Alternatively, the use of a self-contained slot may be based upon a configuration of the sub-slot. Yet alternatively, the use of a self-contained slot may be upon a configuration of a shortened physical channel (e.g. PDSCH, PUSCH, PUCCH, etc.).
The number of aggregated DL control channel elements is referred to as DL control channel element aggregation level. The DL control channel element aggregation level may be 1 or 2 to the power of an integer. The gNB 160 may inform a UE 102 of which control channel candidates are mapped to each subset of OFDM symbols in the control resource set. If one DL control channel is mapped to a single OFDM symbol and does not span multiple OFDM symbols, the DL control channel element aggregation is performed within an OFDM symbol, namely multiple DL control channel elements within an OFDM symbol are aggregated. Otherwise, DL control channel elements in different OFDM symbols can be aggregated.
It should be noted that names of physical channels described herein are examples. The other names such as “New Radio (NR)PDCCH, NRPDSCH, NRPUCCH and NRPUSCH”, “new Generation-(G)PDCCH, GPDSCH, GPUCCH and GPUSCH” or the like can be used.
The UE 1902 may also include a housing that contains one or more transmitters 1958 and one or more receivers 1920 to allow transmission and reception of data. The transmitter(s) 1958 and receiver(s) 1920 may be combined into one or more transceivers 1918. One or more antennas 1922a-n are attached to the housing and electrically coupled to the transceiver 1918.
The various components of the UE 1902 are coupled together by a bus system 1911, which may include a power bus, a control signal bus and a status signal bus, in addition to a data bus. However, for the sake of clarity, the various buses are illustrated in
The gNB 2060 may also include a housing that contains one or more transmitters 2017 and one or more receivers 2078 to allow transmission and reception of data. The transmitter(s) 2017 and receiver(s) 2078 may be combined into one or more transceivers 2076. One or more antennas 2080a-n are attached to the housing and electrically coupled to the transceiver 2076.
The various components of the gNB 2060 are coupled together by a bus system 2011, which may include a power bus, a control signal bus and a status signal bus, in addition to a data bus. However, for the sake of clarity, the various buses are illustrated in
With reference to
Referencing
Again referencing
The mobile station 1902 the receiving circuitry 1920 may also, or alternatively receive a second information used to enable frequency hopping in a frequency domain for the PUCCH format 0. If hopping in the frequency is enabled, the transmitting circuitry 1958 transmits the UCI using the PUCCH format 0 with hopping in the frequency domain, where the number of repetitions in the time domain is applied per hop in the frequency domain.
Referencing
Alternatively or in addition, the base station 2060 transmitting circuitry 2017 is configured to transmit a RRC message including second information used for enabling hopping in a frequency domain for the PUCCH format 0. Then, the receiving circuitry 2078, if hopping in the frequency is enabled, receives the UCI using the PUCCH format 0 with hopping in the frequency domain, where the number of repetitions in the time domain is applied per hop in the frequency domain.
In Step 2508 the mobile station receives a RRC message including second information used for enabling of a hopping in a frequency domain for the PUCCH format 0. If hopping in the frequency is enabled, Step 2510 transmits the UCI using the PUCCH format 0 with hopping in the frequency domain, where the number of repetitions in the time domain is applied per hop in the frequency domain.
Alternatively or in addition, in Step 2608 the base station may transmit a RRC message including second information used for enabling hopping in a frequency domain for the PUCCH format 0. In the case that hopping in the frequency is enabled, Step 2610 receives the UCI using the PUCCH format 0 with hopping in the frequency domain, where the number of repetitions in the time domain is applied per hop in the frequency domain.
The term “computer-readable medium” refers to any available medium that can be accessed by a computer or a processor. The term “computer-readable medium,” as used herein, may denote a computer- and/or processor-readable medium that is non-transitory and tangible. By way of example, and not limitation, a computer-readable or processor-readable medium may comprise random access memory (RAM), read-only memory (ROM), electrically erasable programmable memory (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 or processor. Disk and disc, as used herein, includes compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk and Blu-ray® disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers.
It should be noted that one or more of the methods described herein may be implemented in and/or performed using hardware. For example, one or more of the methods described herein may be implemented in and/or realized using a chipset, an application-specific integrated circuit (ASIC), a large-scale integrated circuit (LSI) or integrated circuit, etc.
Each of the methods disclosed herein comprises one or more steps or actions for achieving the described method. The method steps and/or actions may be interchanged with one another and/or combined into a single step without departing from the scope of the claims. In other words, unless a specific order of steps or actions is required for proper operation of the method that is being described, the order and/or use of specific steps and/or actions may be modified without departing from the scope of the claims.
It is to be understood that the claims are not limited to the precise configuration and components illustrated above. Various modifications, changes and variations may be made in the arrangement, operation and details of the systems, methods, and apparatus described herein without departing from the scope of the claims.
A program running on the gNB 160 or the UE 102 according to the described systems and methods is a program (a program for causing a computer to operate) that controls a CPU and the like in such a manner as to realize the function according to the described systems and methods. Then, the information that is handled in these apparatuses is temporarily stored in a RAM while being processed. Thereafter, the information is stored in various ROMs or HDDs, and whenever necessary, is read by the CPU to be modified or written. As a recording medium on which the program is stored, among a semiconductor (for example, a ROM, a nonvolatile memory card, and the like), an optical storage medium (for example, a DVD, a MO, a MD, a CD, a BD, and the like), a magnetic storage medium (for example, a magnetic tape, a flexible disk, and the like), and the like, any one may be possible.
Furthermore, in some cases, the function according to the described systems and methods described above is realized by running the loaded program, and in addition, the function according to the described systems and methods is realized in conjunction with an operating system or other application programs, based on an instruction from the program. Furthermore, in a case where the programs are available on the market, the program stored on a portable recording medium can be distributed or the program can be transmitted to a server computer that connects through a network such as the Internet. In this case, a storage device in the server computer also is included. Furthermore, some or all of the gNB 160 and the UE 102 according to the systems and methods described above may be realized as an LSI that is a typical integrated circuit. Each functional block of the gNB 160 and the UE 102 may be individually built into a chip, and some or all functional blocks may be integrated into a chip. Furthermore, a technique of the integrated circuit is not limited to the LSI, and an integrated circuit for the functional block may be realized with a dedicated circuit or a general-purpose processor. Furthermore, if with advances in a semiconductor technology, a technology of an integrated circuit that substitutes for the LSI appears, it is also possible to use an integrated circuit to which the technology applies.
Moreover, each functional block or various features of the base station device and the terminal device used in each of the aforementioned embodiments may be implemented or executed by a circuitry, which is typically an integrated circuit or a plurality of integrated circuits. The circuitry designed to execute the functions described in the present specification may comprise a general-purpose processor, a digital signal processor (DSP), an application specific or general application integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic devices, discrete gates or transistor logic, or a discrete hardware component, or a combination thereof. The general-purpose processor may be a microprocessor, or alternatively, the processor may be a conventional processor, a controller, a microcontroller or a state machine. The general-purpose processor or each circuit described above may be configured by a digital circuit or may be configured by an analogue circuit. Further, when a technology of making into an integrated circuit superseding integrated circuits at the present time appears due to advancement of a semiconductor technology, the integrated circuit by this technology is also able to be used.
| Number | Date | Country | |
|---|---|---|---|
| 62692291 | Jun 2018 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/US2019/039147 | Jun 2019 | US |
| Child | 16454207 | US |
