Patent Application
20250016746
Embodiments herein relate to a user equipment (UE), a radio network node and methods performed therein regarding wireless communication. Furthermore, a computer program product and a computer-readable storage medium are also provided herein. Especially, embodiments herein relate to handling or enabling monitoring of a control channel in a wireless communication network.
In a typical wireless communication network, UEs, also known as wireless communication devices, mobile stations, stations (STA) and/or wireless devices, communicate via a Radio access Network (RAN) to one or more core networks (CN). The RAN covers a geographical area which is divided into service areas or cell areas, with each service area or cell area being served by a radio network node such as an access node, e.g., a Wi-Fi access point or a radio base station (RBS), which in some radio access technologies (RAT) may also be called, for example, a NodeB, an evolved NodeB (eNodeB) and a gNodeB (gNB). The service area or cell area is a geographical area where radio coverage is provided by the radio network node. The radio network node operates on radio frequencies to communicate over an air interface with the wireless devices within range of the access node. The radio network node communicates over a downlink (DL) to the wireless device and the wireless device communicates over an uplink (UL) to the access node.
A Universal Mobile Telecommunications System (UMTS) is a third generation telecommunication network, which evolved from the second generation (2G) Global System for Mobile Communications (GSM). The UMTS terrestrial radio access network (UTRAN) is essentially a RAN using wideband code division multiple access (WCDMA) and/or High-Speed Packet Access (HSPA) for communication with user equipments. In a forum known as the Third Generation Partnership Project (3GPP), telecommunications suppliers propose and agree upon standards for present and future generation networks and UTRAN specifically, and investigate enhanced data rate and radio capacity. In some RANs, e.g., as in UMTS, several radio network nodes may be connected, e.g., by landlines or microwave, to a controller node, such as a radio network controller (RNC) or a base station controller (BSC), which supervises and coordinates various activities of the plural radio network nodes connected thereto. The RNCs are typically connected to one or more core networks.
Specifications for the Evolved Packet System (EPS) have been completed within the 3rd Generation Partnership Project (3GPP) and this work continues in the coming 3GPP releases (Rel). The EPS comprises the Evolved Universal Terrestrial Radio Access Network (E-UTRAN), also known as the Long-Term Evolution (LTE) radio access network, and the Evolved Packet Core (EPC), also known as System Architecture Evolution (SAE) core network. E-UTRAN/LTE is a 3GPP radio access technology wherein the radio network nodes are directly connected to the EPC core network. As such, the Radio Access Network (RAN) of an EPS has an essentially “flat” architecture comprising radio network nodes connected directly to one or more core networks.
With the emerging 5G technologies also known as new radio (NR), the use of, e.g., very many transmit- and receive-antenna elements makes it possible to utilize beamforming, such as transmit-side and receive-side beamforming. Transmit-side beamforming means that the transmitter can amplify the transmitted signals in a selected direction or directions, while suppressing the transmitted signals in other directions. Similarly, on the receive-side, a receiver can amplify signals from a selected direction or directions, while suppressing unwanted signals from other directions.
Mobile broadband will continue to drive the demands for big overall traffic capacity and huge achievable end-user data rates in the wireless access network. Several scenarios in the future will require data rates of up to 10 Gbps in local areas. These demands for very high system capacity and very high end-user date rates can be met by networks with distances between access nodes ranging from a few meters in indoor deployments up to roughly 50 m in outdoor deployments, i.e., with an infra-structure density considerably higher than the densest networks of today.
In 3GPP release (Rel)-15, a 5G system referred as New Radio (NR) was specified. NR standard in 3GPP is designed to provide services for multiple use cases such as enhanced mobile broadband (eMBB), ultra-reliable and low latency communication (URLLC), and machine type communication (MTC). Each of these services has different technical requirements. For example, the general requirement for eMBB is high data rate with moderate latency and moderate coverage, while URLLC service requires a low latency and high reliability transmission but perhaps for moderate data rates.
Besides traditional licensed exclusive bands, NR systems are currently being extended expected to operate on unlicensed bands. The NR system specifications currently address two frequency ranges, FR1 and FR2, which are summarized in TABLE 1. To support ever growing mobile traffic, further extension of the NR system to support spectrum higher than 5.26 GHz is expected in the near future.
The downlink transmission waveform in NR is conventional orthogonal frequency division multiplexing (OFDM) using a cyclic prefix. The uplink transmission waveform is conventional OFDM using a cyclic prefix (CP) with a transform precoding function performing discrete fourier transform (DFT) spreading that can be disabled or enabled. The basic transmitter block diagram for NR is illustrated in
Multiple numerologies are supported in NR. A numerology is defined by sub-carrier spacing and CP overhead. Multiple subcarrier spacings (SCS) can be derived by scaling a basic subcarrier spacing by an integer 2μ. The numerology used can be selected independently of the frequency band although it is assumed not to use a very small subcarrier spacing at very high carrier frequencies. Flexible network and UE channel bandwidths are supported. The supported transmission numerologies in NR are summarized in Table 2.
From RAN1 specification perspective, maximum channel bandwidth per NR carrier is 400 MHz in Rel-15. At least for single numerology case, candidates of the maximum number of subcarriers per NR carrier is 3300 in Rel-15 from RAN1 specification perspective.
Downlink and uplink transmissions are organized into frames with 10 ms duration, consisting of ten 1 ms subframes. Each frame is divided into two equally-sized half-frames of five subframes each. The slot duration is 14 symbols with Normal CP and 12 symbols with Extended CP, and scales in time as a function of the used sub-carrier spacing so that there is always an integer number of slots in a subframe. More specifically, the number of slots per subframe is 2μ.
The basic NR downlink physical resource within a slot can thus be seen as a time-frequency grid as illustrated in
In the case of carrier aggregation, multiple NR carriers can be transmitted in parallel to/from the same UE, thereby allowing for an overall wider bandwidth and correspondingly higher per-link data rates. In the context of carrier aggregation, each carrier is referred to as a serving cell in the specifications. In NR, a UE first connects to the network with a serving cell, which becomes the primary cell (PCell) for the UE, which continues to handle the mobility and radio resource control (RRC) connection of the UE. The additional aggregated cells are referred to as the secondary cells (SCells).
In addition to carrier aggregation with one PCell and one or more SCells as one cell group, NR also supports a second cell group with at one primary secondary cell (PSCell) and possible additional SCells in the second cell group.
In 3GPP NR standard, downlink control information (DCI) is received over the PDCCH. The PDCCH may carry DCI in messages with different formats. DCI format 0_0 and 0_1 are DCI messages used to convey uplink grants to the UE for transmission of the physical layer data channel in the uplink, denoted as physical uplink shared channel (PUSCH) and DCI format 1_0 and 1_1 are used to convey downlink grants for transmission of the physical layer data channel on the downlink, denotes as physical downlink shared channel (PDSCH). Other DCI formats, such as 2_0, 2_1, 2_2 and 2_3, are used for other purposes such as transmission of slot format information, reserved resource, transmit power control information etc.
A PDCCH candidate is searched within a common or UE-specific search space which is mapped to a set of time and frequency resources referred to as a control resource set (CORESET) instance. The search spaces within which PDCCH candidates must be monitored are configured to the UE via RRC signaling. A monitoring periodicity is also configured for different search space sets. A CORESET is defined by the frequency domain location and size as well as the time domain size. A CORESET in NR can be 1, 2 or 3 OFDM symbols in duration. The smallest unit used for defining CORESETs is a Resource Element Group (REG), which is defined as spanning 12 subcarriers×1 OFDM symbol in frequency and time. Resource-element groups within a control-resource set are numbered in increasing order in a time-first manner, starting with 0 for the first OFDM symbol and the lowest-numbered resource block in the control resource set. As a result, though different PDCCHs can occupy different amount of frequency domain resources, all PDCCHs in a CORESET have the same duration as the duration of the CORESET.
Each REG contains demodulation reference signals (DMRS) to aid in the estimation of the radio channel over which that REG was transmitted. When transmitting the PDCCH, a precoder could be used to apply weights at the transmit antennas based on some knowledge of the radio channel prior to transmission. It is possible to improve channel estimation performance at the UE by estimating the channel over multiple REGs that are proximate in time and frequency if the precoder used at the transmitter for the REGs is not different. To assist the UE with channel estimation the multiple REGs can be grouped together to form a REG bundle and the REG bundle size for a CORESET is indicated to the UE. The UE may assume that any precoder used for the transmission of the PDCCH is the same for all the REGs in the REG bundle. A REG bundle may consist of 2, 3 or 6 REGs.
A control channel element (CCE) consists of 6 REGs. The REGs within a CCE may either be contiguous or distributed in frequency. When the REGs are distributed in frequency, the CORESET is said to be using an interleaved mapping of REGs to a CCE and if the REGs are not distributed in frequency, a non-interleaved mapping is said to be used.
PDCCHs targeting different coverage ranges are designed based assigning different amount of frequency domain resources to the PDCCHs. A PDCCH candidate may span 1, 2, 4, 8 or 16 CCEs and the number of aggregated CCEs used is referred to as the aggregation level for the PDCCH candidate.
A set of PDCCH candidates for a UE to monitor is defined in terms of PDCCH search space sets. A search space set can be a common search space (CSS) set or a UE-specific search space (USS) set. A UE monitors PDCCH candidates in one or more of the following search spaces sets:
SIB1 is scheduled on PDSCH by PDCCH scrambled with SI-RNTI in the Type0-PDCCH common search space set. If during cell search a UE determines from MIB that a CORESET for Type0-PDCCH CSS set is present, as described in Subclause 4.1 of 38.213, the UE determines a number of consecutive resource blocks and a number of consecutive symbols for the CORESET of the Type0-PDCCH CSS set from controlResourceSetZero (simply an index to a row in a first table) in pdcch-ConfigSIB1, as described in Tables 13-1 through 13-10 in 38.213. These tables provide the configuration, duration, bandwidth, and physical resource block (PRB) location of CORESET0. The UE determines the configuration of the PDCCH monitoring occasions from searchSpaceZero, simply and index to a row in a second table, in pdcch-ConfigSIB1, included in MIB, as described in Tables 13-11 through 13-15 in 38.213 v.16.0.0.
For synchronization signal (SS)/physical broadcast channel (PBCH) block and CORESET multiplexing pattern 1, the UE monitors two consecutive slots starting from the one indicated by the procedure in 38.213 § 13 v.16.0.0 denoted by slot n0 and slot n0+1.
The UE determines which table, Tables 13-1 through 13-10, to use based on a combination of the sub-carrier spacing for the detected SS/PBCH block, as defined in 38.101-1 per band, the sub-carrier spacing of PDCCH, as indicated by subCarrierSpacingCommon in MIB, the frequency range FR1/FR2, and the minimum channel bandwidth, as defined by 38.101-1 per band v.16.0.0.
There are a number of exceptions where 38.101-1/2 defines two different sub-carrier spacings for the SS/PBCH block for a band. For those cases the UE needs to try both sub-carrier spacings when detecting the SS/PBCH block.
In Rel-15/16, the RRC parameter monitoringSlotPeriodicityAndOffset is used to configure the periodicity and offset of the search space.
The parameter duration indicates the number of consecutive slots for PDCCH monitoring occasions within the search space set configuration periodicity. If the field is absent, the UE applies the value 1 slot, except for DCI format 2_0. The UE ignores this field for DCI format 2_0.
The first symbol(s) for PDCCH monitoring in the slots configured for PDCCH monitoring is determined by the bitmap in monitoringSymbolsWithinSlot. The most significant (left) bit represents the first OFDM in a slot, and the second most significant (left) bit represents the second OFDM symbol in a slot and so on. The bit(s) set to one identify the first OFDM symbol(s) of the control resource set within a slot.
PDCCH Processing Capability Requirements and Limitations for High Frequency Systems.
Blind decoding of potential PDCCH transmissions is attempted by the UE in each of the configured PDCCH candidates within a slot. In any particular slot, the UE may be configured to monitor multiple PDCCH candidates in multiple search spaces which may be mapped to one or more CORESETs. PDCCH candidates may need to be monitored multiple times in a slot, once every slot or once in multiple of slots. The maximum number of PDCCH candidates that can be monitored by a UE for a carrier within a slot are summarized in Table 3. The complexity incurred at the UE to do this depends on the number of CCEs which need to be processed to test all the candidates in the CORESET. Channel estimation is a key contributor to the complexity incurred by the UE. The maximum number of CCEs of channel estimation supported by the UE for a carrier within a slot are summarized in Table 3.
Table 3 shows Maximum number of PDCCH candidates and maximum number of CCE for channel estimation within a slot for a carrier.
The Rel-15 PDCCH processing capabilities per slot can be fitted to simple formulae to obtain initial benchmarks for further discussion. Using the minimum mean absolute deviation fitting, the fitted formulae is given by
The fitted and extrapolated PDCCH processing capabilities per slot are shown in Table 4, where the values for 240 kHz SCS and above are extrapolated values for sub-carrier spacings larger than 120 kHz. Since NCCE,μslot for μ=0 and μ=1 are identical, the fitting takes a nominal μ=0.5 to pair with NCCE,μslot=56 as input. It can be observed that UE processing capabilities may become extremely limited when using large sub-carrier spacing and very short frame structures for high-frequency bands. There are then doubts on whether the UE operating with ≥1920 kHz SCS can support even one aggregation level (AL)-16 PDCCH or the default number of candidates for monitoring the seven PDCCH candidates in Type0A-PDCCH CSS as specified in NR specs.
One possible direction is to reduce the periodicity of PDCCH monitoring at a UE to allow more time for the UE to process the PDCCH candidates. For instance,
Thus,
As the operating frequency of wireless networks increases and moves to milli-meter wave territory, data transmission between nodes suffers from high propagation loss, which is proportional to the square of the carrier frequency. Moreover, milli-meter wave signal also suffers from high oxygen absorption, high penetration loss and a variety of blockage problems. On the other hand, with the wavelength as small as less than a centi-meter, it becomes possible to pack a large amount, tens, hundreds or even thousands, of antenna elements into a single antenna array with a compact formfactor, which can be widely adopted in a network equipment and a user device. Such antenna arrays and/or panels can generate narrow beams with high beam forming gain to compensate for the high path loss in mm-wave communications, as well as providing highly directional transmission and reception pattern. As a consequence, directional transmission and reception are the distinguishing characteristics for wireless networks in mm-wave bands. In the case of analog beamforming where the amplitude and/or phase of each antenna element is adjusted as RF, a transmitter/receiver can typically only transmit/receive in one direction at a time, or if the UE is equipped with two or more panels, a few directions at any given time. This is in contrast to digital or hybrid analog-digital beamforming, where the phase weights are applied at baseband allowing different beam directions in different frequency sub-bands.
To support beam-based operation in NR, a UE can be configured with a number of transmission configuration indicator (TCI) states. A TCI state, see below extract from 38.331 v.16.0.0, provides the UE with the ID of one or two reference signals, where each reference signal can be an SS/PBCH block or a channel state information reference signal (CSI-RS). A quasi-co-location (QCL) type is associated with each of the reference signals of the TCI state, and the type can take one of 4 possible values: TypeA, TypeB, TypeC, or TypeD. A particular TCI state is indicated to the UE to aid in the reception of other signals/channels in the DL, e.g., PDSCH, PDCCH, other CSI-RS, etc. The indication of the TCI state to aid in reception of a DL signal is performed through either dynamic or semi-static signaling, i.e., via DCI, medium access control (MAC)-control element (CE), or by RRC depending on the DL signal to be received. For example, for reception of PDCCH, a TCI state is indicated by MAC-CE signaling.
QCL type is related to the spatial domain receiver settings in the UE, i.e., the setting of the spatial domain receive filter, receive beamforming weights. Hence, if TypeD is configured for one of the reference signals of the indicated TCI state for reception of a DL signal, e.g., PDCCH, it tells the UE that it can receive the PDCCH with the same spatial domain receiver settings as it used to receive the reference signal configured with TypeD within the TCI state. The implicit assumption is that the UE has previously performed measurements on this reference signal and “remembers” which spatial domain receiver settings it used for reception of that reference signal. In other words, the TCI state provides a means to indicate to the UE which receive beam to use for reception of the DL signal, e.g., PDCCH.
The indication (activation) of the TCI state to aid in reception of PDCCH is performed by MAC-CE signaling according to the following extract from 3GPP TS 38.321. The highlighted text covers the case where MAC-CE activates the TCI state for CORESET0. When MAC-CE indicates (activates) the TCI state for CORESET0, then this TCI state is used for the reception of PDCCH detected in any search space that has configured association to CORESET0, e.g., a search space with index 0, SS0.
The TCI State Indication for UE-specific PDCCH MAC CE is identified by a MAC subheader with logic channel identity (LCID) as specified in Table 6.2.1-1. It has a fixed size of 16 bits with following fields:
Through indication (activation) of a TCI state, the UE is able to know which direction to tune its receive beam towards the serving gNB for reception of a particular signal or channel, e.g., PDCCH. Based on prior UE measurements and reporting to the gNB, the gNB is able to know how to tune its Tx beam towards the UE. An illustrative example is shown in
For the case of a Type0/0A/2 PDCCH detected in search space 0 (SS0) associated with CORESET0, the TCI state update procedure is described in 3GPP TS 38.213 v.16.0.0 as follows:
If a UE is provided a zero value for searchSpaceID in PDCCH-ConfigCommon for a Type0/0A/2-PDCCH CSS set, the UE determines monitoring occasions for PDCCH candidates of the Type0/0A/2-PDCCH CSS set as described in clause 13, and the UE is provided a C-RNTI, the UE monitors PDCCH candidates only at monitoring occasions associated with a SS/PBCH block, where the SS/PBCH block is determined by the most recent of
This procedure also states where the UE shall monitor for the CSS PDCCH. The time domain location, i.e., slot, of the monitoring occasions is a function of the SS/PBCH block determined according to the above procedure.
As part of developing embodiments herein one or more problems have been identified.
For the large subcarrier spacings (480, 960 kHz) introduced in Rel-17, it becomes clear that reducing the periodicity of PDCCH monitoring at the UE side can allow more time for the UE to process the PDCCH candidates since the slot duration for the large SCSs becomes quite short. However, it is important to simultaneously consider both UE capability and gNB/network scheduling flexibility. What is needed from a gNB point of view is to be able to stagger USSs for different UEs in different slots based on the preferred spatial beams.
Three alternatives have been proposed to define a multi-slot monitoring capability suitable for the new large SCSs:
In terms of UE energy savings, smaller Y values (e.g., Y≤1 slot) are preferred. However, as described in the above, the current initial access procedure is built on UE monitoring two consecutive slots for type0 PDCCH. Furthermore, it has been recognized that none of the three alternatives with small Y values and without further changes can support mobility-induced TCI state changes where the time domain monitoring location associated with an SS/PBCH block needs to change.
One may to solve the problems identified in the above:
For either approach, a search space can be configured with a granularity of X-slot groups (which includes the periodicity in terms of X-slot groups, offset in terms of X-slot groups within the period, and duration in terms of X-slot groups within the period). However, the key aspect is that the slot location of the search spaces within an X-slot group is not configurable. Rather, for a given UE, they are confined within the same Y-slot duration, and the Y slot duration has location corresponding to the first slot of the Type0 CSS within an X-slot group determined by that UE.
An object of embodiments herein is to provide a mechanism that improves the performance in the wireless communication network.
Embodiments herein further provide details and procedures for carrier aggregation or dual connectivity cases and allow compatible search space monitoring occasions between PCell/PSCell and SCells. This enables UE energy saving by supporting small Y values and mobility-induced spatial QCL (TCI state) changes, and simultaneously allows network flexibility to stagger UE specific search spaces in different slots.
According to an aspect the object is achieved by providing a method performed by a UE for handling communication in a wireless communication network. The UE selects for a Pcell and/or a Scell, a search space slot within a slot group wherein the slot group is arranged in an X-slot group pattern, wherein the slot group is of a size of X-slots, and the X-slot group pattern is fixed relative to a reference time location and common for UEs operating PDCCH monitoring X slots. The UE further monitors the selected search space slot or slots for a control channel of the Pcell, and/or the Scell. For example, a method performed by a UE for monitoring a control channel in a wireless communication network.
According to another aspect the object is achieved by providing a method performed by a radio network node for handling communication in a wireless communication network. The radio network node transmits configuration to a UE for monitoring, for a Pcell and/or a Scell, a search space slot within a slot group wherein the slot group is arranged in an X-slot group pattern, wherein the slot group is of a size of X-slots, and the X-slot group pattern is fixed relative to a reference time location and common for UEs operating physical downlink control channel, PDCCH, monitoring X slots. For example, a method performed by a radio network node for handling monitoring of a control channel in a wireless communication network. The configuration may comprise a period in terms of number of slot groups; an offset in terms of number of slot groups within the period; a duration in terms of number of slot groups within the period, and an indication of symbol with a slot. Furthermore, the configuration may comprise a deciding indication for the UE to select a search space slot according to any of the methods mentioned herein.
According to still another aspect the object is achieved by providing a UE and a radio network node configured to perform the methods herein.
Thus, it is herein provided a UE for handling communication in a wireless communication network. The UE is configured to select for a Pcell and/or a Scell, a search space slot within a slot group wherein the slot group is arranged in an X-slot group pattern, wherein the slot group is of a size of X-slots, and the X-slot group pattern is fixed relative to a reference time location and common for UEs operating PDCCH monitoring X slots. The UE is further configured to monitor the selected search space slot or slots for a control channel of the Pcell, and/or the Scell.
It is also herein provided a radio network node for handling communication in a wireless communication network. The radio network node is configured to transmit configuration to a UE for monitoring, for a Pcell and/or a Scell, a search space slot within a slot group wherein the slot group is arranged in an X-slot group pattern, wherein the slot group is of a size of X-slots, and the X-slot group pattern is fixed relative to a reference time location and common for UEs operating physical downlink control channel, PDCCH, monitoring X slots.
It is furthermore provided herein a computer program product comprising instructions, which, when executed on at least one processor, cause the at least one processor to carry out any of the methods above, as performed by the UE and radio network node, respectively. It is additionally provided herein a computer-readable storage medium, having stored thereon a computer program product comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method according to any of the methods above, as performed by the UE or the radio network node, respectively.
The herein proposed embodiments allow UE energy saving by supporting small Y values and mobility-induced spatial QCL, or TCI state, changes, and simultaneously allow network flexibility to stagger UE specific search spaces in different slots, resulting in an improved performance of the wireless communication network.
Embodiments will now be described in more detail in relation to the enclosed drawings, in which:
Embodiments herein are described within the context of 3GPP NR radio technology (3GPP TS 38.300 V15.2.0 (2018-06)). It is understood, that the problems and solutions described herein are equally applicable to wireless access networks and user-equipments (UEs) implementing other access technologies and standards. NR is used as an example technology where embodiments are suitable, and using NR in the description therefore is particularly useful for understanding the problem and solutions solving the problem. In particular, embodiments are applicable also to 3GPP LTE, or 3GPP LTE and NR integration, also denoted as non-standalone NR.
Embodiments herein relate to wireless communication networks in general.
In the wireless communication network 1, wireless devices, e.g., a UE 10 such as a mobile station, a non-access point (non-AP) STA, a STA, a user equipment and/or a wireless terminal, communicate via one or more Access Networks (AN), e.g. RAN, to one or more core networks (CN). It should be understood by the skilled in the art that “UE” is a non-limiting term which means any terminal, wireless communication terminal, user equipment, internet of things (IoT) capable device, Machine Type Communication (MTC) device, Device to Device (D2D) terminal, or node e.g. smart phone, laptop, mobile phone, sensor, relay, mobile tablets or even a small base station capable of communicating using radio communication with a network node within an area served by the network node.
The wireless communication network 1 comprises a first radio network node 12 providing radio coverage over a geographical area, a first service area 11, of a radio access technology (RAT), such as LTE, Wi-Fi, WiMAX or similar. The first radio network node 12 may be a transmission and reception point e.g. a radio network node such as a Wireless Local Area Network (WLAN) access point or an Access Point Station (AP STA), an access node, an access controller, a base station, e.g. a radio base station such as a NodeB, an evolved Node B (eNB, eNode B), a gNodeB (gNB), a base transceiver station, a radio remote unit, an Access Point Base Station, a base station router, a transmission arrangement of a radio base station, a stand-alone access point or any other network unit or node capable of communicating with a UE within the area served by the first radio network node 12 depending e.g. on the radio access technology and terminology used. The first radio network node 12 may alternatively or additionally be a controller node or a packet processing node such as a radio controller node or similar. The first radio network node 12 may be referred to as the radio network node or as a serving network node wherein the first cell may be referred to as a serving cell or primary cell, and the serving network node communicates with the UE 10 in form of DL transmissions to the UE 10 and UL transmissions from the UE 10.
The wireless communication network 1 comprises a second radio network node 13 providing radio coverage over a geographical area, a second service area 14, of a radio access technology (RAT), such as LTE, Wi-Fi, WiMAX or similar. The second radio network node 13 may be a transmission and reception point e.g. a radio network node such as a Wireless Local Area Network (WLAN) access point or an Access Point Station (AP STA), an access node, an access controller, a base station, e.g. a radio base station such as a NodeB, an evolved Node B (eNB, eNode B), a gNodeB (gNB), a base transceiver station, a radio remote unit, an Access Point Base Station, a base station router, a transmission arrangement of a radio base station, a stand-alone access point or any other network unit or node capable of communicating with a UE within the area served by the second radio network node 13 depending e.g. on the radio access technology and terminology used. The second radio network node 13 may alternatively or additionally be a controller node or a packet processing node such as a radio controller node or similar. The second radio network node 13 may be referred to as a secondary serving network node, or secondary network node, wherein the second service area may be referred to as a secondary serving cell or secondary cell, and the secondary serving network node communicates with the UE 10 in form of DL transmissions to the UE 10 and UL transmissions from the UE 10.
It should be noted that a service area may be denoted as cell, beam, beam group or similar to define an area of radio coverage.
According to embodiments herein methods allow UE energy saving by supporting small Y values and mobility-induced spatial QCL, or TCI state, changes, and simultaneously allow network flexibility to stagger UE specific search spaces in different slots.
For the proposed solution, the following is considered:
Note that in a general scenario the term “radio network node” can be substituted with “transmission point”. Distinction between the transmission points (TPs) may typically be based on cell specific reference signals or different synchronization signals transmitted. Several TPs may be logically connected to the same radio network node but if they are geographically separated, or are pointing in different propagation directions, the TPs may be subject to the same mobility issues as different radio network nodes. In subsequent sections, the terms “radio network node” and “TP” can be thought of as interchangeable.
The method actions performed by the UE 10 for handling communication in the wireless communication network 1 according to embodiments will now be described with reference to a flowchart depicted in
Action 501. The UE 10 may receive a configuration from a radio network node such as the first radio network node 12 or the second radio network node 13. The configuration may comprise a period in terms of number of slot groups; an offset in terms of number of slot groups within the period; a duration in terms of number of slot groups within the period, and an indication of symbol within a slot. The configuration may further comprise a deciding indication indicating a method to use to select search space slot.
Action 502. The UE 10 selects for a Pcell and/or a Scell, a search space slot within a slot group wherein the slot group is arranged in an X-slot group pattern, wherein the slot group is of a size of X-slots, and the X-slot group pattern is fixed relative to a reference time location and common for UEs operating PDCCH monitoring X slots. The UE 10 may select the search space slot by determining a search space monitoring slot within an X-slot group based on a location of a first slot of a type0 CSS monitoring occasion for the PCell, a PSCell and/or the SCell within a slot group. Alternatively, the UE 10 may select the search space slot by determining a slot group grid offset for a SCell based on at least a slot index of a first slot of a type0 CSS monitoring occasion on the PCell or primary secondary cell, PSCell.
Action 503. The UE 10 monitors the selected search space slot or slots for a control channel of the Pcell, and/or the Scell.
Action 504. The UE 10 may change search space in response to receiving an instruction from a radio network node to change search space, or by autonomously determining a new type0 PDCCH monitoring location during a random access procedure.
The method actions performed by the radio network node, such as the first radio network node 12 or the second radio network node 13, for handling communication in the wireless communication network 1 according to embodiments will now be described with reference to a flowchart depicted in
Action 511. The radio network node transmits configuration to the UE 10 for monitoring, for a Pcell, and/or a Scell, the search space slot within the slot group wherein the slot group is arranged in the X-slot group pattern, wherein the slot group is of a size of X-slots, and the X-slot group pattern is fixed relative to the reference time location and common for UEs operating PDCCH monitoring X slots. The configuration may comprise the period in terms of number of slot groups; the offset in terms of number of slot groups within the period; the duration in terms of number of slot groups within the period, and the indication of symbol within a slot. The configuration may further comprise the deciding indication indicating the method to use to select search space slot.
Action 512. The radio network node may further transmit an instruction to the UE 10 to change search space.
Below are described different ways to select the search space slot within a slot group.
For a given X slot group size, the X-slot group pattern is fixed relative to a reference time location and common for all UEs operating PDCCH monitoring every X slots. For example, the X-slot group starts from the first slot in an even indexed radio frame.
The UE 10 receives a search space configuration from the radio network node for
The UE determines the start of a X-slot group based on the location of the first slot of the type0 CSS monitoring occasions (denoted by n0 in the current NR system specs).
The UE 10 receives a search space configuration from the radio network node for
For a given X slot group size, the X-slot group pattern is fixed relative to a reference time location and common for all UEs operating PDCCH monitoring every X slots. For example, the X-slot group starts from the first slot in an even indexed radio frame.
The UE 10 receives a search space configuration from a network node for
The UE 10 determines the search space monitoring slot within an X-slot group (denoted as the monitoringSlotWithinSlotGroup) based on the location of the first slot of the type0 CSS monitoring occasions (denoted by n0 in the current NR system specs) within a slot group. As one nonlimiting embodiment, the UE determines
monitoringSlotWithinSlotGroup=n0 modulo X
The UE 10 determines the slot indices to monitor the configured search space as follows:
(period*p+offset+y)*X+monitoringSlotWithinSlotGroup
When the UE 10 receives instruction from the radio network node to change the type0 PDCCH monitoring location(s) (i.e., change in no), the UE 10 determines a new value for monitoringSlotWithinSlotGroup according to the new type0 PDCCH monitoring location(s) and determines the slot indices to monitor all search spaces according to the new monitoringSlotWithinSlotGroup.
As a nonlimiting exemplary embodiment, the UE 10 receives a search space configuration from the radio network node for the case X=4:
The X-slot groups that will contain the search space monitoring occasions as illustrated in
Furthermore, suppose the first slot of the type0 CSS monitoring occasions is n0=22. The UE 10 thus determines
This monitoringSlotWithinSlotGroup is then applied to the configured search space as illustrated in
(5*p+1+y)*4+2 for y=0,1 and p=0,1,2 . . . .
Finally, the configured monitoringSymbolsWithinSlot is applied to the determined monitoring slots for the configured search space.
As an extension to the above embodiment, the UE 10 receives an extraSlotOffsetWithinSlotGroup parameter in addition to the search space configuration listed above. The UE 10 determines the slot indices to monitor the configured search space as follows:
(period*p+offset+y)*X+monitoringSlotWithinSlotGroup+extraSlotOffsetWithinSlotGroup
Alternatively, the UE 10 determines the slot indices to monitor the configured search space as follows:
(period*p+offset+y)*X+((monitoringSlotWithinSlotGroup+extraSlotOffsetWithinSlotGroup)modulo X)
Another alternative is for the UE 10 to determine the slot indices to monitor the configured search space as follows:
(period*p+offset+y)*X+((no+extraSlotOffsetWithinSlotGroup)modulo X)
Embodiments for cases where the multi-slot PDCCH monitoring is not used for PCell/PSCell.
For the carrier aggregation/dual connectivity cases where multi-slot PDCCH monitoring is not used for the PCell or PSCell, then all the cells with multi-slot PDCCH monitoring are SCells. For these cases, monitoringSlotWithinSlotGroup is set to 0 for applying the above embodiments to the monitoring occasion determination for search spaces for the SCells.
Embodiments for cases where the multi-slot PDCCH monitoring is used for PCell/PSCell and SCells.
For the general case, the UE 10 determines monitoringSlotWithinSlotGroup for the SCell based on at least the slot index of the first slot of the type0 CSS monitoring occasions (denoted by n0 in the current NR system specs) on the PCell/PSCell as follows:
monitoringSlotWithinSlotGroup=floor(n0×2μ
Further elaboration, examples and variations of the above embodiment and teaching are presented in the following sections.
As another nonlimiting exemplary embodiment, the UE 10 determines monitoringSlotWithinSlotGroup for the SCell as follows:
monitoringSlotWithinSlotGroup=ceil(n0×2μ
Embodiments for cases where the PCell/PSCell and the SCell have the same numerology.
When multi-slot PDCCH monitoring of the same group size is used for the PCell/PSCell and the SCell having the same numerology, the monitoringSlotWithinSlotGroup calculated for the PCell/PSCell using the first slot of the type0 CSS monitoring occasions (denoted by n0 in the current NR system specs) on the PCell/PSCell is applied to the SCell for determining monitoring occasions for search spaces on the SCell. This is because μs−μp=0 and Xs=Xp such that, for the SCell,
monitoringSlotWithinSlotGroup=floor(n0×20)modulo Xs=n0 modulo Xp.
As a nonlimiting exemplary embodiment, the UE 10 receives a search space configuration from a network node for the SCell and with the case X=4:
Furthermore, suppose the first slot of the type0 CSS monitoring occasions on the PCell/PSCell is n0=18. The UE 10 thus determines
monitoringSlotWithinSlotGroup=18 modulo 4=2.
This monitoringSlotWithinSlotGroup is then applied to the configured search space for the SCell as illustrated in
(5*p+1+y)*4+2 for y=0,1 and p=0,1,2 . . . .
Embodiments for cases where the PCell/PSCell numerology is smaller than and the SCell numerology.
When the PCell/PSCell numerology (denoted by μp) is smaller than the SCell numerology (denoted by μs), a slot duration on the PCell/PSCell is longer than the slot duration on the SCell as illustrated in
To enable UE power saving, it's desirable to align the PDCCH monitoring occasions across the different serving cells and reduce the time the UE 10 needs to power up electronics for PDCCH monitoring. It is therefore beneficial to using a large slot group size X for a serving cell with larger numerology. As a nonlimiting embodiment, X=4 is used for a PCell/PSCell with 480 kHz SCS (which is μp=5) and X=8 is used for a SCell with 960 kHz SCS (which is μs=6). Such numerology-dependent slot group size configuration enables the slot groups across different serving cells with different numerologies to be aligned as illustrated in
For the case where the SCell numerology (denoted by μs) is one level larger than the PCell/PSCell numerology (denoted by μp) and SCell slot group size (denoted by Xs) is twice of PCell/PSCell slot group size (denoted by Xp), the UE 10 can determine monitoringSlotWithinSlotGroup for the SCell as two times the monitoringSlotWithinSlotGroup determined for the PCell/PSCell:
monitoringSlotWithinSlotGroups=2*monitoringSlotWithinSlotGroupp
For the general case, the UE 10 can determine monitoringSlotWithinSlotGroup for the SCell from the index of the first slot of the type0 CSS monitoring occasions (denoted by n0 in the current NR system specs) on the PCell/PSCell as follows:
monitoringSlotWithinSlotGroups=(n0×2μ
For the general case, the UE 10 can determine monitoringSlotWithinSlotGroup for the SCell from the monitoringSlotWithinSlotGroup determined for the PCell/PSCell as follows:
monitoringSlotWithinSlotGroups=(monitoringSlotWithinSlotGroupp×2μ
For the general case, the UE 10 may also determine monitoringSlotWithinSlotGroup for the SCell from the index of the first slot of the type0 CSS monitoring occasions (denoted by n0 in the current NR system specs) on the PCell/PSCell as follows:
As a nonlimiting exemplary embodiment for the case where PCell/PSCell numerology is μ−1, the PCell/PSCell slot group size X=4, and the SCell numerology is μ, the UE 10 receives a search space configuration from a network node for the SCell and with the case X=8:
Furthermore, suppose the first slot of the type0 CSS monitoring occasions on the PCell/PSCell is n0=18. The UE 10 determines the monitoringSlotWithinSlotGroup for the PCell/PSCell as
monitoringSlotWithinSlotGroupp=18 modulo 4=2.
The UE 10 determines the monitoringSlotWithinSlotGroup for the SCell as
monitoringSlotWithinSlotGroups=2*monitoringSlotWithinSlotGroupp=4
Alternatively, the UE can determine the monitoringSlotWithinSlotGroup for the SCell as
This monitoringSlotWithinSlotGroups is then applied to the configured search space as illustrated in
(5*p+1+y)*8+4 for y=0,1 and p=0,1,2 . . . .
As another nonlimiting exemplary embodiment for the case where PCell/PSCell numerology is μ−1, the PCell/PSCell slot group size X=4, and the SCell numerology is μ, the UE 10 receives a search space configuration from a network node for the SCell and with the case X=4:
Furthermore, suppose the first slot of the type0 CSS monitoring occasions on the PCell/PSCell is n0=18. As described in the above, the UE 10 determines monitoringSlotWithinSlotGroupp=2. The UE 10 determines the monitoringSlotWithinSlotGroup for the SCell as
monitoringSlotWithinSlotGroups=(2×2μ−(μ−1))modulo 4=0.
That is, for this example, the monitoring occasions of the configured search space on the SCell with X=4 is at the beginning of the slot groups as illustrated in
Embodiments for cases where the PCell/PSCell numerology is larger than and the SCell numerology.
When the PCell/PSCell numerology (denoted by μp) is larger than the SCell numerology (denoted by μs), a slot duration on the PCell/PSCell is shorter than the slot duration on the SCell as illustrated in
For the general case, the UE 10 can determine monitoringSlotWithinSlotGroup for the SCell from the index of the first slot of the type0 CSS monitoring occasions (denoted by n0 in the current NR system specs) on the PCell/PSCell as follows:
monitoringSlotWithinSlotGroups=floor(n0×2μ
As a nonlimiting exemplary embodiment, the UE 10 receives a search space configuration from a network node for the SCell and with the case X=4:
Furthermore, suppose the first slot of the type0 CSS monitoring occasions on the Pcell/PSCell is n0=21. The UE 10 thus determines for the SCell
monitoringSlotWithinSlotGroups=floor(21×2(μ−1)−μ)modulo 4=10 modulo 4=2.
This monitoringSlotWithinSlotGroup is then applied to the configured search space for the SCell as illustrated in
(5*p+1+y)*4+2 for y=0,1 and p=0,1,2 . . . .
The UE 10 determines the start of a X-slot group based on the location of the first slot of the type0 CSS monitoring occasions (denoted by n0 in the current NR system specs).
The UE 10 receives a search space configuration from the radio network node for
The UE 10 determines the start of a X-slot group based on the location of the first slot of the type0 CSS monitoring occasions (denoted by n0 in the current NR system specs) such that the first slot of the type0 CSS monitoring occasions is also a first slot of a slot group. That is, a X-slot group consists of the X consecutive slots starting from a slot with index n:
To simply the notation and presentation, a slot group grid offset is defined as
n
0,X
=n
0 modulo X.
That is, a X-slot group consists of the X consecutive slots starting from a slot with index n:
The search space monitoring slot within a X-slot group is always at the beginning of a X-slot group (i.e., monitoringSlotWithinSlotGroup=0). The UE 10 determines the slot indices to monitor the configured search space as follows:
When the UE 10 receives instruction from the radio network node to change the type0 PDCCH monitoring location(s), the UE 10 determines slot indices to monitor for all search spaces according to the new first slot of the type0 CSS monitoring occasions (denoted by n0 in the current NR system specs).
In one variation of the embodiment the instruction from the radio network node can be a MAC-CE activation of a new TCI state, where the TCI state is either configured with the ID of an SS/PBCH block or is configured with the ID of a channel state information reference signal (CSI-RS) that is quasi co-located (QCL'd) with an SS/PBCH block.
In another variation, rather than receiving an explicit instruction from the radio network node to change the type0 PDCCH monitoring location the UE 10 autonomously determines a new type0 PDCCH monitoring location during a random access procedure (RACH). In this variation, the UE 10 determines a new value of n0 based on a preferred SS/PBCH block detected by the UE 10 which is associated with a random access occasion (RO) used by the UE 10 during the RACH procedure.
As a nonlimiting exemplary embodiment, the UE 10 receives a search space configuration from a network node for the case X=4:
Furthermore, suppose the first slot of the type0 CSS monitoring occasions is n0=22. The X-slot groups that will contain the search space monitoring occasions and the slots to be monitored for the configured search space are as illustrated in
As an extension to embodiments, the UE 10 receives an extraSlotOffsetWithinSlotGroup parameter in addition to the other search space configuration as above.
The UE 10 determines the slot indices to monitor the configured search space as follows:
(period*p+offset+y)*X+n0,X+extraSlotOffsetWithinSlotGroup
Alternatively, the UE 10 determines the slot indices to monitor the configured search space as follows:
Embodiments for cases where the multi-slot PDCCH monitoring is not used for PCell/PSCell.
For the carrier aggregation/dual connectivity cases where multi-slot PDCCH monitoring is not used for the PCell or PSCell, then all the cells with multi-slot PDCCH monitoring are SCells. For these cases, the slot group is aligned with the frame or the subframe of the NR serving cell. That is, a X-slot group consists of the X consecutive slots starting from a slot with index n:
Embodiments for cases where the multi-slot PDCCH monitoring is used for PCell/PSCell and SCells.
For the general case, the UE 10 determines the slot group grid offset for the SCell based on at least the slot index of the first slot of the type0 CSS monitoring occasions (denoted by n0 in the current NR system specs) on the PCell/PSCell as follows:
Further elaboration, examples and variations of the above main embodiment and teaching are presented in the following sections.
As another nonlimiting exemplary embodiment, the UE determines slot group grid offset for the SCell as follows:
Embodiments for cases where the PCell/PSCell and the SCell have the same numerology.
When multi-slot PDCCH monitoring of the same group size is used for the PCell/PSCell and the SCell having the same numerology, the slot group grid offset calculated for the PCell/PSCell using the first slot of the type0 CSS monitoring occasions (denoted by n0 in the current NR system specs) on the PCell/PSCell is applied to the SCell for determining monitoring occasions for search spaces on the SCell. This is because μs−μp=0 and Xs=Xp=X such that, for the SCell,
As a nonlimiting exemplary embodiment, the UE 10 receives a search space configuration from a network node for the SCell and with the case X=4:
Furthermore, suppose the first slot of the type0 CSS monitoring occasions on the Pcell/PSCell is n0=18. The UE 10 thus determines
n
0,X=18 modulo 4=2.
This is then applied to the configured search space for the SCell as illustrated in
Embodiments for cases where the PCell/PSCell numerology is smaller than and the SCell numerology.
When the PCell/PSCell numerology (denoted by μp) is smaller than the SCell numerology (denoted by μs), a slot duration on the PCell/PSCell is longer than the slot duration on the SCell as illustrated in
To enable UE power saving, it's desirable to align the PDCCH monitoring occasions across the different serving cells and reduce the two time the UE needs to power up electronics for PDCCH monitoring. It is therefore beneficial to using a large slot group size X for a serving cell with larger numerology. As a nonlimiting embodiment, X=4 is used for a PCell/PSCell with 480 kHz SCS (which is μp=5) and X=8 is used for a SCell with 960 kHz SCS (which is μs=6). Such numerology-dependent slot group size configuration enables the slot groups across different serving cells with different numerologies to be aligned as illustrated in
For the case where the SCell numerology (denoted by μs) is one level larger than the PCell/PSCell numerology (denoted by μp) and SCell slot group size (denoted by Xs) is twice of PCell/PSCell slot group size (denoted by Xp), the UE can determine the slot group grid offset for the SCell as two times the slot group grid offset determined for the PCell/PSCell:
For the general case, the UE 10 may determine the slot group grid offset for the SCell from the index of the first slot of the type0 CSS monitoring occasions (denoted by n0 in the current NR system specs) on the PCell/PSCell as follows:
For the general case, the UE 10 may determine the slot group grid offset for the SCell from the slot group grid offset determined for the PCell/PSCell as follows:
For the general case, the UE 10 may also determine the slot group grid offset for the SCell from the index of the first slot of the type0 CSS monitoring occasions (denoted by n0 in the current NR system specs) on the PCell/PSCell as follows:
As a nonlimiting exemplary embodiment for the case where PCell/PSCell numerology is μ−1, the PCell/PSCell slot group size X=4, and the SCell numerology is μ, the UE 10 receives a search space configuration from a network node for the SCell and with the case X=8:
Furthermore, suppose the first slot of the type0 CSS monitoring occasions on the PCell/PSCell is n0=18. The UE 10 determines the slot group grid offset for the PCell/PSCell as
The UE 10 determines the slot group grid offset for the SCell as
Alternatively, the UE 10 determines the slot group grid offset for the SCell as
n
0,X
=(18×2μ−(μ−1))modulo 8=4,
This is then applied to the configured search space as illustrated in
As another nonlimiting exemplary embodiment for the case where PCell/PSCell numerology is μ−1, the PCell/PSCell slot group size X=4, and the SCell numerology is μ, the UE 10 receives a search space configuration from a network node for the SCell and with the case X=4:
Furthermore, suppose the first slot of the type0 CSS monitoring occasions on the PCell/PSCell is n0=18. As described in the above, the UE determines slot group grid offset for the PCell/PSCell as n0,X
That is, for this example, the monitoring occasions of the configured search space on the SCell with X=4 is at the beginning of the slot groups as illustrated in
Embodiments for cases where the PCell/PSCell numerology is larger than and the SCell numerology.
When the PCell/PSCell numerology (denoted by μp) is larger than the SCell numerology (denoted by μs), a slot duration on the PCell/PSCell is shorter than the slot duration on the SCell as illustrated in
For the general case, the UE 10 may determine slot group grid offset for the SCell from the index of the first slot of the type0 CSS monitoring occasions (denoted by n0 in the current NR system specs) on the PCell/PSCell as follows:
As a nonlimiting exemplary embodiment, the UE 10 receives a search space configuration from a network node for the SCell and with the case X=4:
Furthermore, suppose the first slot of the type0 CSS monitoring occasions on the PCell/PSCell is n0=21. The UE 10 thus determines for the SCell
This is then applied to the configured search space for the SCell as illustrated in
Action 301. The radio network node such as the first radio network node 12 or the second radio network node 13 may transmit configuration to the UE for monitoring a PCell and/or Scell. The configuration is for search space comprising a period in terms of number of slot groups; an offset in terms of number of slot groups within the period; a duration in terms of number of slot groups within the period, and an indication of symbol with a slot. Furthermore, the configuration may comprise the deciding indication for the UE 10 to select a search space slot according to any of the methods mentioned herein.
Action 302. The UE 10 selects, for a Pcell and/or an Scell, a search space slot within a slot group according to any of the embodiments herein.
Action 303. The UE 10 monitors the selected search space for the control channel as configured according to any of the embodiments mentioned herein.
The UE 10 may comprise processing circuitry 1801, e.g. one or more processors, configured to perform the methods herein.
The UE 10 may comprise a receiving unit 1802, e.g. a receiver or a transceiver. The UE 10, the processing circuitry 1801, and/or the receiving unit 1802 may be configured to receive the configuration from the radio network node. The configuration may comprise a period in terms of number of slot groups; an offset in terms of number of slot groups within the period; a duration in terms of number of slot groups within the period, and an indication of symbol within a slot. The configuration may further comprise the deciding indication indicating a method to use to select search space slot.
The UE 10 may comprise a selecting unit 1803. The UE 10, the processing circuitry 1801, and/or the selecting unit 1803 is configured to select for a Pcell and/or an Scell, the search space slot within the slot group according to any of the embodiments herein. The UE 10, the processing circuitry 1801, and/or the selecting unit 1803 is configured to select for a Pcell, and/or a Scell, a search space slot within a slot group wherein the slot group is arranged in an X-slot group pattern, wherein the slot group is of a size of X-slots, and the X-slot group pattern is fixed relative to a reference time location and common for UEs operating PDCCH monitoring X slots. The UE 10, the processing circuitry 1801, and/or the selecting unit 1803 may be configured to select the search space slot by determining a search space monitoring slot within an X-slot group based on a location of a first slot of a type0 CSS monitoring occasion for the PCell, a PSCell, and/or the SCell within a slot group.
The UE 10 may comprise a monitoring unit 1804. The UE 10, the processing circuitry 1801, and/or the monitoring unit 1804 is configured to monitor the selected search space, e.g., as configured according to any of the embodiments mentioned herein. The UE 10, the processing circuitry 1801, and/or the monitoring unit 1804 is configured to monitor the selected search space slot or slots for a control channel of the Pcell, and/or the Scell. The UE 10, the processing circuitry 1801, and/or the selecting unit 1803 may be configured to select the search space slot by determining a slot group grid offset for a SCell based on at least a slot index of a first slot of a type0 CSS monitoring occasion on the PCell or a PSCell. The UE 10, the processing circuitry 1801, and/or the selecting unit 1803 may be configured to change search space in response to receiving an instruction from a radio network node to change search space, or by autonomously determining a new type0 PDCCH monitoring location during a random access procedure.
The UE 10 further comprises a memory 1805. The memory comprises one or more units to be used to store data on, such as configuration, slot number, search space, indications, thresholds, indications, RSs, strengths or qualities, UL grants, indications, requests, commands, timers, applications to perform the methods disclosed herein when being executed, and similar. Thus, embodiments herein may disclose a UE for monitoring a control channel in a wireless communication network, wherein the UE comprises processing circuitry and a memory, said memory comprising instructions executable by said processing circuitry whereby said UE is operative to perform any of the methods herein. The UE comprises a communication interface 1808 comprising a transmitter, a receiver and/or one or more antennas.
The methods according to the embodiments described herein for the UE 10 are respectively implemented by means of e.g. a computer program product 1806 or a computer program, comprising instructions, i.e., software code portions, which, when executed on at least one processor, cause the at least one processor to carry out the actions described herein, as performed by the UE 10. The computer program product 1806 may be stored on a computer-readable storage medium 1807, e.g. a universal serial bus (USB) stick, a disc or similar. The computer-readable storage medium 1807, having stored thereon the computer program product, may comprise the instructions which, when executed on at least one processor, cause the at least one processor to carry out the actions described herein, as performed by the UE 10. In some embodiments the computer-readable storage medium may be a non-transitory or a transitory computer-readable storage medium.
The radio network node may comprise processing circuitry 1901, e.g. one or more processors, configured to perform the methods herein.
The radio network node may comprise a configuring unit 1902, e.g. a transmitter or a transceiver. The radio network node, the processing circuitry 1901, and/or the configuring unit 1902 is configured to transmit configuration to the UE for monitoring, for a PCell and/or Scell, the search space slot within the slot group wherein the slot group is arranged in an X-slot group pattern, wherein the slot group is of a size of X-slots, and the X-slot group pattern is fixed relative to the reference time location and common for UEs operating PDCCH monitoring X slots. The configuration may comprise the period in terms of number of slot groups; the offset in terms of number of slot groups within the period; the duration in terms of number of slot groups within the period, and the indication of symbol within a slot. The configuration may further comprise the deciding indication indicating a method to use to select search space slot. The configuration is for search space comprising a period in terms of number of slot groups; an offset in terms of number of slot groups within the period; a duration in terms of number of slot groups within the period, and an indication of symbol with a slot. Furthermore, the configuration comprises the deciding indication for the UE to select a search space slot according to any of the methods mentioned herein. The radio network node, the processing circuitry 1901, and/or the configuring unit 1902 is configured to transmit the instruction to the UE 10 to change search space.
The radio network node further comprises a memory 1903. The memory comprises one or more units to be used to store data on, such as configurations, thresholds, measurements, aggregation information, indications, strengths or qualities, grants, scheduling information, timers, applications to perform the methods disclosed herein when being executed, and similar. Thus, embodiments herein may disclose a radio network node for handling communication such as monitoring a control channel in a wireless communication network, wherein the radio network node comprises processing circuitry and a memory, said memory comprising instructions executable by said processing circuitry whereby said radio network node is operative to perform any of the methods herein. The radio network node comprises a communication interface 1906 comprising transmitter, receiver, transceiver and/or one or more antennas.
The methods according to the embodiments described herein for the radio network node are respectively implemented by means of e.g. a computer program product 1904 or a computer program product, comprising instructions, i.e., software code portions, which, when executed on at least one processor, cause the at least one processor to carry out the actions described herein, as performed by the radio network node. The computer program product 1904 may be stored on a computer-readable storage medium 1905, e.g., a USB stick, a disc or similar. The computer-readable storage medium 1905, having stored thereon the computer program product, may comprise the instructions which, when executed on at least one processor, cause the at least one processor to carry out the actions described herein, as performed by the radio network node. In some embodiments, the computer-readable storage medium may be a non-transitory or transitory computer-readable storage medium.
In some embodiments a more general term “radio network node” is used and it can correspond to any type of radio network node or any network node, which communicates with a wireless device and/or with another network node. Examples of network nodes are NodeB, Master eNB, Secondary eNB, a network node belonging to Master cell group (MCG) or Secondary Cell Group (SCG), base station (BS), multi-standard radio (MSR) radio node such as MSR BS, eNodeB, network controller, radio network controller (RNC), base station controller (BSC), relay, donor node controlling relay, base transceiver station (BTS), access point (AP), transmission points, transmission nodes, Remote Radio Unit (RRU), Remote Radio Head (RRH), nodes in distributed antenna system (DAS), core network node e.g. Mobility Switching Centre (MSC), Mobile Management Entity (MME) etc., Operation and Maintenance (O&M), Operation Support System (OSS), Self-Organizing Network (SON), positioning node e.g. Evolved Serving Mobile Location Centre (E-SMLC), Minimizing Drive Test (MDT) etc.
In some embodiments the non-limiting term wireless device or user equipment (UE) is used and it refers to any type of wireless device communicating with a network node and/or with another UE in a cellular or mobile communication system. Examples of UE are target device, device-to-device (D2D) UE, proximity capable UE (aka ProSe UE), machine type UE or UE capable of machine to machine (M2M) communication, PDA, PAD, Tablet, mobile terminals, smart phone, laptop embedded equipped (LEE), laptop mounted equipment (LME), USB dongles etc.
The embodiments are described for 5G. However the embodiments are applicable to any RAT or multi-RAT systems, where the UE receives and/or transmit signals (e.g. data) e.g. LTE, LTE FDD/TDD, WCDMA/HSPA, GSM/GERAN, Wi Fi, WLAN, CDMA2000 etc.
As will be readily understood by those familiar with communications design, that functions means or modules may be implemented using digital logic and/or one or more microcontrollers, microprocessors, or other digital hardware. In some embodiments, several or all of the various functions may be implemented together, such as in a single application-specific integrated circuit (ASIC), or in two or more separate devices with appropriate hardware and/or software interfaces between them. Several of the functions may be implemented on a processor shared with other functional components of a wireless device or network node, for example.
Alternatively, several of the functional elements of the processing means discussed may be provided through the use of dedicated hardware, while others are provided with hardware for executing software, in association with the appropriate software or firmware. Thus, the term “processor” or “controller” as used herein does not exclusively refer to hardware capable of executing software and may implicitly include, without limitation, digital signal processor (DSP) hardware, read-only memory (ROM) for storing software, random-access memory for storing software and/or program or application data, and non-volatile memory. Other hardware, conventional and/or custom, may also be included. Designers of communications devices will appreciate the cost, performance, and maintenance trade-offs inherent in these design choices.
With reference to
The telecommunication network 3210 is itself connected to a host computer 3230, which may be embodied in the hardware and/or software of a standalone server, a cloud-implemented server, a distributed server or as processing resources in a server farm. The host computer 3230 may be under the ownership or control of a service provider, or may be operated by the service provider or on behalf of the service provider. The connections 3221, 3222 between the telecommunication network 3210 and the host computer 3230 may extend directly from the core network 3214 to the host computer 3230 or may go via an optional intermediate network 3220. The intermediate network 3220 may be one of, or a combination of more than one of, a public, private or hosted network; the intermediate network 3220, if any, may be a backbone network or the Internet; in particular, the intermediate network 3220 may comprise two or more sub-networks (not shown).
The communication system of
Example implementations, in accordance with an embodiment, of the UE, base station and host computer discussed in the preceding paragraphs will now be described with reference to
The communication system 3300 further includes a base station 3320 provided in a telecommunication system and comprising hardware 3325 enabling it to communicate with the host computer 3310 and with the UE 3330. The hardware 3325 may include a communication interface 3326 for setting up and maintaining a wired or wireless connection with an interface of a different communication device of the communication system 3300, as well as a radio interface 3327 for setting up and maintaining at least a wireless connection 3370 with a UE 3330 located in a coverage area (not shown in
The communication system 3300 further includes the UE 3330 already referred to. Its hardware 3335 may include a radio interface 3337 configured to set up and maintain a wireless connection 3370 with a base station serving a coverage area in which the UE 3330 is currently located. The hardware 3335 of the UE 3330 further includes processing circuitry 3338, which may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. The UE 3330 further comprises software 3331, which is stored in or accessible by the UE 3330 and executable by the processing circuitry 3338. The software 3331 includes a client application 3332. The client application 3332 may be operable to provide a service to a human or non-human user via the UE 3330, with the support of the host computer 3310. In the host computer 3310, an executing host application 3312 may communicate with the executing client application 3332 via the OTT connection 3350 terminating at the UE 3330 and the host computer 3310. In providing the service to the user, the client application 3332 may receive request data from the host application 3312 and provide user data in response to the request data. The OTT connection 3350 may transfer both the request data and the user data. The client application 3332 may interact with the user to generate the user data that it provides.
It is noted that the host computer 3310, base station 3320 and UE 3330 illustrated in
In
The wireless connection 3370 between the UE 3330 and the base station 3320 is in accordance with the teachings of the embodiments described throughout this disclosure. One or more of the various embodiments improve the performance of OTT services provided to the UE 3330 using the OTT connection 3350, in which the wireless connection 3370 forms the last segment. More precisely, the teachings of these embodiments may improve the performance since signalling of the control channel in CA or DC is handled more efficiently and thereby provide benefits such as better battery consumption, reduced user waiting time, and better responsiveness.
A measurement procedure may be provided for the purpose of monitoring data rate, latency and other factors on which the one or more embodiments improve. There may further be an optional network functionality for reconfiguring the OTT connection 3350 between the host computer 3310 and UE 3330, in response to variations in the measurement results. The measurement procedure and/or the network functionality for reconfiguring the OTT connection 3350 may be implemented in the software 3311 of the host computer 3310 or in the software 3331 of the UE 3330, or both. In embodiments, sensors (not shown) may be deployed in or in association with communication devices through which the OTT connection 3350 passes; the sensors may participate in the measurement procedure by supplying values of the monitored quantities exemplified above, or supplying values of other physical quantities from which software 3311, 3331 may compute or estimate the monitored quantities. The reconfiguring of the OTT connection 3350 may include message format, retransmission settings, preferred routing etc.; the reconfiguring need not affect the base station 3320, and it may be unknown or imperceptible to the base station 3320. Such procedures and functionalities may be known and practiced in the art. In certain embodiments, measurements may involve proprietary UE signaling facilitating the host computer's 3310 measurements of throughput, propagation times, latency and the like. The measurements may be implemented in that the software 3311, 3331 causes messages to be transmitted, in particular empty or ‘dummy’ messages, using the OTT connection 3350 while it monitors propagation times, errors etc.
It will be appreciated that the foregoing description and the accompanying drawings represent non-limiting examples of the methods and apparatus taught herein. As such, the apparatus and techniques taught herein are not limited by the foregoing description and accompanying drawings. Instead, the embodiments herein are limited only by the following claims and their legal equivalents.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/SE2022/051014 | 11/4/2022 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 63263587 | Nov 2021 | US |
