Group common PDCCH design in NR

In an aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus may be a user equipment (UE). The UE receives symbols in a first time slot. The first time slot includes a control region and a data region. The UE attempts to detect, when the UE is configured to detect, a group common downlink control channel carried by the received symbols. The group common downlink control channel contains common information directed to a group of UEs including the UE. When the detection is successful, the UE determines, based on the common information, at least one of (a) a first slot configuration, (b) a puncture configuration, (c) a transmission burst duration, and (d) one or more sub-regions of the control region.

BACKGROUND

Field

The present disclosure relates generally to communication systems, and more particularly, to user equipment (UE) that processes group common PDCCH.

Background

SUMMARY

In an aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus may be a UE of a wireless communication system. The UE receives symbols in a first time slot. The first time slot includes a control region and a data region. The UE attempts to detect, when the UE is configured to detect, a group common downlink control channel carried by the received symbols. The group common downlink control channel contains common information directed to a group of UEs including the UE.

When the detection is successful, the UE determines, based on the common information, at least one of (a) a first slot configuration of one or more time slots, (b) a puncture configuration indicating one or more punctured symbols received in a second time slot, the one or more punctured symbols being initially allocated for carrying enhanced Mobile Broadband (eMBB) data and carrying Ultra-Reliable and Low Latency Communications (URLLC) data, the second time slot being prior to the first time slot, (c) a transmission burst duration of a transmission on an unlicensed link, the unlicensed link being in an unlicensed spectrum, and (d) one or more sub-regions of the control region containing one or more of the received symbols that are a part of a downlink data channel, the downlink data channel including one or more of the received symbols in the data region.

DETAILED DESCRIPTION

The detailed description set forth below in connection with the appended drawings is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced.

The detailed description includes specific details for the purpose of providing a thorough understanding of various concepts. However, it will be apparent to those skilled in the art that these concepts may be practiced without these specific details. In some instances, well known structures and components are shown in block diagram form in order to avoid obscuring such concepts.

In certain aspects, the UE104determines, via a CSI component192, a plurality of messages containing channel state information to be reported to a base station. The UE104also determines, via a reporting module194, a priority level for each of the plurality of messages based on at least one predetermined rule. The UE104further selects one or more messages from the plurality of messages based on priority levels of the plurality of messages. The UE104then sends the selected one or more messages to the base station.

In certain aspects, the UE104determines, via the CSI component192, a first message and a second message containing channel state information to be reported to a base station. The UE104also determines, via the reporting module194, that a priority level of the first message is higher than a priority level of the second message based on at least one predetermined rule. The UE104further maps sets of information bits of the first message to a first plurality of input bits of an encoder and sets of information bits of the second message to a second plurality of input bits of the encoder. The first plurality of input bits offer an error protection level higher than an error protection level offered by the second plurality of input bits.

FIG. 2Ais a diagram200illustrating an example of a DL frame structure.FIG. 2Bis a diagram230illustrating an example of channels within the DL frame structure.FIG. 2Cis a diagram250illustrating an example of an UL frame structure.FIG. 2Dis a diagram280illustrating an example of channels within the UL frame structure. Other wireless communication technologies may have a different frame structure and/or different channels. A frame (10 ms) may be divided into 10 equally sized subframes. Each subframe may include two consecutive time slots. A resource grid may be used to represent the two time slots, each time slot including one or more time concurrent resource blocks (RBs) (also referred to as physical RBs (PRBs)). The resource grid is divided into multiple resource elements (REs). For a normal cyclic prefix, an RB contains 12 consecutive subcarriers in the frequency domain and 7 consecutive symbols (for DL, OFDM symbols; for UL, SC-FDMA symbols) in the time domain, for a total of 84 REs. For an extended cyclic prefix, an RB contains 12 consecutive subcarriers in the frequency domain and 6 consecutive symbols in the time domain, for a total of 72 REs. The number of bits carried by each RE depends on the modulation scheme.

As illustrated inFIG. 2A, some of the REs carry DL reference (pilot) signals (DL-RS) for channel estimation at the UE. The DL-RS may include cell-specific reference signals (CRS) (also sometimes called common RS), UE-specific reference signals (UE-RS), and channel state information reference signals (CSI-RS).FIG. 2Aillustrates CRS for antenna ports 0, 1, 2, and 3 (indicated as R0, R1, R2, and R3, respectively), UE-RS for antenna port 5 (indicated as R5), and CSI-RS for antenna port 15 (indicated as R).FIG. 2Billustrates an example of various channels within a DL subframe of a frame. The physical control format indicator channel (PCFICH) is within symbol 0 of slot 0, and carries a control format indicator (CFI) that indicates whether the physical downlink control channel (PDCCH) occupies 1, 2, or 3 symbols (FIG. 2Billustrates a PDCCH that occupies 3 symbols). The PDCCH carries downlink control information (DCI) within one or more control channel elements (CCEs), each CCE including nine RE groups (REGs), each REG including four consecutive REs in an OFDM symbol. A UE may be configured with a UE-specific enhanced PDCCH (ePDCCH) that also carries DCI. The ePDCCH may have 2, 4, or 8 RB pairs (FIG. 2Bshows two RB pairs, each subset including one RB pair). The physical hybrid automatic repeat request (ARQ) (HARQ) indicator channel (PHICH) is also within symbol 0 of slot 0 and carries the HARQ indicator (HI) that indicates HARQ acknowledgement (ACK)/negative ACK (NACK) feedback based on the physical uplink shared channel (PUSCH). The primary synchronization channel (PSCH) may be within symbol 6 of slot 0 within subframes 0 and 5 of a frame. The PSCH carries a primary synchronization signal (PSS) that is used by a UE to determine subframe/symbol timing and a physical layer identity. The secondary synchronization channel (SSCH) may be within symbol 5 of slot 0 within subframes 0 and 5 of a frame. The SSCH carries a secondary synchronization signal (SSS) that is used by a UE to determine a physical layer cell identity group number and radio frame timing. Based on the physical layer identity and the physical layer cell identity group number, the UE can determine a physical cell identifier (PCI). Based on the PCI, the UE can determine the locations of the aforementioned DL-RS. The physical broadcast channel (PBCH), which carries a master information block (MIB), may be logically grouped with the PSCH and SSCH to form a synchronization signal (SS) block. The MIB provides a number of RBs in the DL system bandwidth, a PHICH configuration, and a system frame number (SFN). The physical downlink shared channel (PDSCH) carries user data, broadcast system information not transmitted through the PBCH such as system information blocks (SIBs), and paging messages.

As illustrated inFIG. 2C, some of the REs carry demodulation reference signals (DM-RS) for channel estimation at the base station. The UE may additionally transmit sounding reference signals (SRS) in the last symbol of a subframe. The SRS may have a comb structure, and a UE may transmit SRS on one of the combs. The SRS may be used by a base station for channel quality estimation to enable frequency-dependent scheduling on the UL.FIG. 2Dillustrates an example of various channels within an UL subframe of a frame. A physical random access channel (PRACH) may be within one or more subframes within a frame based on the PRACH configuration. The PRACH may include six consecutive RB pairs within a subframe. The PRACH allows the UE to perform initial system access and achieve UL synchronization. A physical uplink control channel (PUCCH) may be located on edges of the UL system bandwidth. The PUCCH carries uplink control information (UCI), such as scheduling requests, a channel quality indicator (CQI), a precoding matrix indicator (PMI), a rank indicator (RI), and HARQ ACK/NACK feedback. The PUSCH carries data, and may additionally be used to carry a buffer status report (BSR), a power headroom report (PHR), and/or UCI.

Channel estimates derived by a channel estimator358from a reference signal or feedback transmitted by the base station310may be used by the TX processor368to select the appropriate coding and modulation schemes, and to facilitate spatial processing. The spatial streams generated by the TX processor368may be provided to different antenna352via separate transmitters354TX. Each transmitter354TX may modulate an RF carrier with a respective spatial stream for transmission. The UL transmission is processed at the base station310in a manner similar to that described in connection with the receiver function at the UE350. Each receiver318RX receives a signal through its respective antenna320. Each receiver318RX recovers information modulated onto an RF carrier and provides the information to a RX processor370.

New radio (NR) may refer to radios configured to operate according to a new air interface (e.g., other than Orthogonal Frequency Divisional Multiple Access (OFDMA)-based air interfaces) or fixed transport layer (e.g., other than Internet Protocol (IP)). NR may utilize OFDM with a cyclic prefix (CP) on the uplink and downlink and may include support for half-duplex operation using time division duplexing (TDD). NR may include Enhanced Mobile Broadband (eMBB) service targeting wide bandwidth (e.g. 80 MHz beyond), millimeter wave (mmW) targeting high carrier frequency (e.g. 60 GHz), massive MTC (mMTC) targeting non-backward compatible MTC techniques, and/or mission critical targeting ultra-reliable low latency communications (URLLC) service.

A single component carrier bandwidth of 100 MHZ may be supported. In one example, NR resource blocks (RBs) may span 12 sub-carriers with a sub-carrier bandwidth of 75 kHz over a 0.1 ms duration or a bandwidth of 15 kHz over a 1 ms duration. Each radio frame may consist of 10 or 50 subframes with a length of 10 ms. Each subframe may have a length of 1 ms or 0.2 ms. Each subframe may indicate a link direction (i.e., DL or UL) for data transmission and the link direction for each subframe may be dynamically switched. Each subframe may include DL/UL data as well as DL/UL control data. UL and DL subframes for NR may be as described in more detail below with respect toFIGS. 6 and 7.

FIG. 4illustrates an example logical architecture400of a distributed RAN, according to aspects of the present disclosure. A 5G access node406may include an access node controller (ANC)402. The ANC may be a central unit (CU) of the distributed RAN400. The backhaul interface to the next generation core network (NG-CN)404may terminate at the ANC. The backhaul interface to neighboring next generation access nodes (NG-ANs) may terminate at the ANC. The ANC may include one or more TRPs408(which may also be referred to as BSs, NR BSs, Node Bs, 5G NBs, APs, or some other term). As described above, a TRP may be used interchangeably with “cell.”

The respective TRPs408may be a distributed unit (DU). The TRPs may be coupled to one ANC (ANC402) or more than one ANC (not illustrated). For example, for RAN sharing, radio as a service (RaaS), and service specific AND deployments, the TRP may be coupled to more than one ANC. A TRP may include one or more antenna ports. The TRPs may be configured to individually (e.g., dynamic selection) or jointly (e.g., joint transmission) serve traffic to a UE.

The local architecture of the distributed RAN400may be used to illustrate fronthaul definition. The architecture may be defined to support fronthauling solutions across different deployment types. For example, the architecture may be based on transmit network capabilities (e.g., bandwidth, latency, and/or jitter). The architecture may share features and/or components with LTE. According to aspects, the next generation AN (NG-AN)410may support dual connectivity with NR. The NG-AN may share a common fronthaul for LTE and NR.

The architecture may enable cooperation between and among TRPs408. For example, cooperation may be preset within a TRP and/or across TRPs via the ANC402. According to aspects, no inter-TRP interface may be needed/present.

According to aspects, a dynamic configuration of split logical functions may be present within the architecture of the distributed RAN400. The PDCP, RLC, MAC protocol may be adaptably placed at the ANC or TRP.

FIG. 5illustrates an example physical architecture of a distributed RAN500, according to aspects of the present disclosure. A centralized core network unit (C-CU)502may host core network functions. The C-CU may be centrally deployed. C-CU functionality may be offloaded (e.g., to advanced wireless services (AWS)), in an effort to handle peak capacity. A centralized RAN unit (C-RU)504may host one or more ANC functions. Optionally, the C-RU may host core network functions locally. The C-RU may have distributed deployment. The C-RU may be closer to the network edge. A distributed unit (DU)506may host one or more TRPs. The DU may be located at edges of the network with radio frequency (RF) functionality.

FIG. 6is a diagram600showing an example of a DL-centric subframe. The DL-centric subframe may include a control portion602. The control portion602may exist in the initial or beginning portion of the DL-centric subframe. The control portion602may include various scheduling information and/or control information corresponding to various portions of the DL-centric subframe. In some configurations, the control portion602may be a physical DL control channel (PDCCH), as indicated inFIG. 6. The DL-centric subframe may also include a DL data portion604. The DL data portion604may sometimes be referred to as the payload of the DL-centric subframe. The DL data portion604may include the communication resources utilized to communicate DL data from the scheduling entity (e.g., UE or BS) to the subordinate entity (e.g., UE). In some configurations, the DL data portion604may be a physical DL shared channel (PDSCH).

The DL-centric subframe may also include a common UL portion606. The common UL portion606may sometimes be referred to as an UL burst, a common UL burst, and/or various other suitable terms. The common UL portion606may include feedback information corresponding to various other portions of the DL-centric subframe. For example, the common UL portion606may include feedback information corresponding to the control portion602. Non-limiting examples of feedback information may include an ACK signal, a NACK signal, a HARQ indicator, and/or various other suitable types of information. The common UL portion606may include additional or alternative information, such as information pertaining to random access channel (RACH) procedures, scheduling requests (SRs), and various other suitable types of information.

As illustrated inFIG. 6, the end of the DL data portion604may be separated in time from the beginning of the common UL portion606. This time separation may sometimes be referred to as a gap, a guard period, a guard interval, and/or various other suitable terms. This separation provides time for the switch-over from DL communication (e.g., reception operation by the subordinate entity (e.g., UE)) to UL communication (e.g., transmission by the subordinate entity (e.g., UE)). One of ordinary skill in the art will understand that the foregoing is merely one example of a DL-centric subframe and alternative structures having similar features may exist without necessarily deviating from the aspects described herein.

FIG. 7is a diagram700showing an example of an UL-centric subframe. The UL-centric subframe may include a control portion702. The control portion702may exist in the initial or beginning portion of the UL-centric subframe. The control portion702inFIG. 7may be similar to the control portion602described above with reference toFIG. 6. The UL-centric subframe may also include an UL data portion704. The UL data portion704may sometimes be referred to as the pay load of the UL-centric subframe. The UL portion may refer to the communication resources utilized to communicate UL data from the subordinate entity (e.g., UE) to the scheduling entity (e.g., UE or BS). In some configurations, the control portion702may be a physical DL control channel (PDCCH).

As illustrated inFIG. 7, the end of the control portion702may be separated in time from the beginning of the UL data portion704. This time separation may sometimes be referred to as a gap, guard period, guard interval, and/or various other suitable terms. This separation provides time for the switch-over from DL communication (e.g., reception operation by the scheduling entity) to UL communication (e.g., transmission by the scheduling entity). The UL-centric subframe may also include a common UL portion706. The common UL portion706inFIG. 7may be similar to the common UL portion706described above with reference toFIG. 7. The common UL portion706may additionally or alternatively include information pertaining to channel quality indicator (CQI), sounding reference signals (SRSs), and various other suitable types of information. One of ordinary skill in the art will understand that the foregoing is merely one example of an UL-centric subframe and alternative structures having similar features may exist without necessarily deviating from the aspects described herein.

FIG. 8is a diagram illustrating a communication network800in which a base station802transmits a DL transmission to one or more UEs of a group that are in a cell of the base station802, shown as UEs804-1,804-2, . . .804-G, and referred to collectively or generally as UEs804. “G” is the number of UEs804in the group, without limitation to a particular number G. The DL transmissions include symbols sent via one or more carriers820. The symbols are provided in a plurality of slots810-1,810-2, . . .810-N, referred to collectively or generally as slots810. The base station802can send PDCCHs in each of the slots810to the UEs804. The PDCCHs can include UE-specific PDCCHs directed to a particular UE, such as UE804-1, and a group-common (GC)-PDCCH directed to all of the UEs804-1,804-2, . . .804-G in the group. In the example shown, a GC-PDCCH is sent via the slot810-10. Slot810-10includes a control region832and a data region834. The GC-PDCCH is provided in the control region832. The slots are transmitted over a frequency and time domain with the direction of time T indicated by an arrow. Accordingly, slots810-8and810-9(and an unlimited number of slots not shown) were sent before the slot810-10, and slots810-11and810-12(and an unlimited number of slots not shown) are to be sent after the slot810-10.

The base station802can provide common information in the GC-PDCCH. Examples of common information that can be included are a slot configuration for the slot810-10and/or one or more other slots that will be transmitted after slot810-10(e.g., slots810-11,810-12, . . .810-N), a puncture configuration indicating one or more punctured symbols received in a slot810that was sent prior to slot810-10(e.g., slot810-9), a transmission burst duration of a transmission on an unlicensed link in an unlicensed spectrum for a transmission to be transmitted after slot810-10(e.g., slots810-11and810-12), and a resource allocation indication indicating one or more sub-regions of slot810-10's control region832that are not allocated for PDCCH and can contain one or more symbols that are a part of PDSCH that is also transmitted in the data region834.

The slot configuration can indicate whether the slot810-10and/or one or more of slots that will be transmitted after slot810-10(e.g., slots810-10,810-11,810-12, . . .810-N) will be used for UL transmissions or DL transmissions.

The slot configuration can further indicate when a slot that was originally designated to be used for a DL transmission to one of the UEs is now designated to be used for UL transmissions to another UE804. When a UE learns from the slot configuration that it is not scheduled for a particular slot, that UE can refrain from decoding a UE-specific PDCCH for that slot, from conducting a radio resource management (RRM) measurement for that slot, and/or from conducting a channel state information (CSI) measurement for that slot, thus preserving resources of the unscheduled UEs.

In an example scenario, UE804-1was originally scheduled for receiving a DL transmission in slot810-11from the base station802, but determined from a slot configuration included in common information provided in slot810-10that slot810-11is now designated for UL transmission from UE804-2. UE804-1can decide to refrain from decoding the PDCCH in slot810-11, and can further decide to refrain from conducting RRM measurement and/or CSI measurement for slot810-11, as UE804-1does not transmit UL data in slot810-11and does not need to obtain control information from the control region of slot810-11.

When dynamic TDD is available, similar to the flexibility provided with enhanced Interference Mitigation and Traffic Adaptation (eIMTA), the TDD pattern can be adapted dynamically, such as in response to varying capacity requirements in UL and DL. For example when using dynamic TDD, DL and UL subframe resources can be tailored in response to quick variations and burstiness of DL/UL traffic.

However, dynamic TDD can result in interference experienced by UL and DL transmissions in adjacent cells.

The slot configuration can further include a slot type that indicates whether a slot810is designated to operate as a semi-static or flexible slot. Semi-static slots (also referred to as fixed slots) are designated semi-statically for use as UL or DL slots. Flexible slots can change designations between UL and DL. Such semi-static slots may experience only light interference, and can behave differently than flexible slots that can experience heavy interference. For example, CSI measurement behavior and UL power behavior of a semi-static DL slot can be different when compared to a flexible DL slot.

Accordingly, UE804-1can decide to perform different types of CSI measurement for a DL slot810-11based on whether the slot type indicates that slot810-11is semi-static of flexible. Also, UE804-1can decide to perform different types of power control for an UL slot810-11based on whether the slot type indicates that slot810-11is semi-static of flexible.

FIG. 9Ashows a diagram of example slots having different slot sub-types. The slot configuration can further indicate a slot sub-type, such as a UL priority bi-directional slot902-1, or a DL priority bi-directional slot902-2. When a slot includes both DL transmission portion906and UL transmission portion904, a gap908is provided between the DL transmission portion906and UL transmission portion904. A UL priority bi-directional slot subtype refers to the duration of the UL transmission portion904of the slot being longer than that of the DL transmission portion906. A DL priority bi-directional slot subtype refers to the duration of the DL transmission portion906of the slot810being longer than that of the UL transmission portion904. The sub-type affects the location of the gap908. In certain configurations, the base station and the UEs may implement clear channel assessment (CCA). A busy tone under CCA may be inserted at different locations for the UL priority bi-directional slot902-1and the DL priority bi-directional slot902-2. As such, knowledge about the sub-type can help the UE correctly perform CCA.

A UE can use the sub-type designation to derive the timing of a detection period during which an energy detection of the CCA is performed. The detection period is also designated for transmission of a busy tone by the base station802or a UE.

Thus, the UE can also use the sub-type designation to determine the timing of a detection period, when to conduct transmission of a busy tone, and whether to conduct transmission of a busy tone in the detection period.

A UE can further use the sub-type designation to select an energy detection threshold for CCA, wherein the energy detection threshold can also be used for performing listen-before-talk (LBT) when using an unlicensed channel in an unlicensed spectrum. In addition, the UEs can use the sub-type designation to control power when a slot is used for UL transmission.

The slot configuration can further indicate a gap period between the control region and the data region of a slot810. For example, to support dynamic TDD (especially in unlicensed spectrum), a gap period can be provided from the point of view of a UE for CCA, such that channel sensing can be performed and/or a busy tone signal can be inserted by base station or UE in the gap period. In certain configurations, the GC-PDCCH may contain the gap period information of a particular UE (e.g., UE804-1). As such, other UEs (e.g., UEs804-2and804-3) can use the gap period to avoid erroneous adjustment of automatic gain control (AGC) according to transmission (e.g., busy tone) in the gap period.

The common information can further include a transmission burst duration that indicates the duration of a transmission burst acquired by the base station802. The transmission burst is a transmission on a link in an unlicensed spectrum. The transmission burst duration can facilitate proper LBT performance by the UEs804and increase efficiency. For example, LBT schemes can be categorized as follows.Category 1: No LBTCategory 2: LBT without random back-offCategory 3: LBT with random back-off with fixed size of contention windowCategory 4: LBT with random back-off with variable size of contention window

Using the transmission burst duration, a UE can, for example, convert a category 4 LBT into a category 2 LBT if it is transmitted together with the transmission burst acquired by the base station802.

When the UE receives the transmission burst duration via the common information, the UE can detect a start of a DL transmission on the unlicensed link. The UE can determine that a particular time slot is within the transmission burst based on the time burst duration, and demodulate symbols received in the particular time slot.

In an example, knowing the start and duration of a transmission burst based on a transmission burst duration provided in the GC PDCCH, UE804-1can select a time point within the transmission burst, perform an LBT operation at the time point selected without random backoff, and transmit data in a UL on the unlicensed link when the unlicensed link is determined to be clear by the LBT operation.

Further, the common information can also include puncture configuration to indicate the presence and location of puncture information in a previous slot. For example, puncture configuration included in the common information of a GC-PDCCH received by the UEs at slot810-10can indicate the presence and location of puncture information in slot810-9.

FIG. 9Bshows a diagram of an example slot810-9that includes eMBB data930for UEs804-1,804-2, and/or804-3, and further includes URLLC data932for804-2that punctures the eMBB data930. Upon receiving the URLLC data932, the UE for which it is intended, namely UE804-2, can decode the URLLC data932. However, UEs804-1and804-3were not aware of the URLLC data932when it was received and may have failed to decode the punctured eMBB data930due to missing data of the eMBB data930caused by the puncture.

Once UEs804-1,804-2, and804-3receive the puncture information in the common information provided in the GC-PDCCH when processing the slot810-10, the UEs804-1and804-3first become aware that the previous slot810-9was punctured by the URLLC data932. If the eMBB data930was not successfully decoded, UEs804-1and804-3can attempt a second time to decode the eMBB data930by skipping the resources of slot810-9that are occupied by URLLC data932. In this manner, UEs804-1and804-3may correctly decode eMBB data930. Alternatively, upon receiving the puncture information, if the eMBB data930was not successfully decoded, the UEs804-1and804-3can send a negative acknowledgement to the base station802, such as a NACK according to HARQ-ACK/NACK feedback timing. As such, the UEs804-1and804-3requests the base station802to re-transmit the eMBB data930in the slot810-9. When the base station802re-transmits the eMBB data930without being punctured by the URLLC data932, the UEs804-1and804-3may successfully decode the eMBB data930.

The common information can further include a resource allocation indication that indicates resource allocation for the group-control slot810-10and/or any slot810that includes GC PDCCH or UE-specific PDCCH. The resource allocation indicates which resources are used by PDCCH. Based on the resource allocation indication, the UEs can determine which resources are unused. The base station802can be configured to use unused resources for transmission of PDSCH, but only using those unused resources that are restricted to the same frequency as PDSCH transmitted in a corresponding data region.

FIG. 9Cshows a diagram of an example slot950having a control region954that includes PDCCH and unused resources that are available to be used for PDSCH956. The slot950can be the group-control slot810-10or any other slot that includes PDCCH. Slot950includes a data region952and the control region954. The data region952includes PDSCH956that is assigned to one of the UEs804-1,802-2, . . .802-G. The control region954includes PDCCH958and unused resources960. The resource allocation indication received by the UEs inform the UEs which resources in the control region954are occupied by PDCCH958. Based on this knowledge of the resources that are already allocated for occupation by PDCCH958, the UEs can determine which resources are unused and available to be used for data transmission. Each UE can be configured to determine whether the unused resources960that use the same frequency as PDSCH in a corresponding data region were used for data transmission for that UE. The UE can thus perform correct de-rate matching without the need for performing blind detections to determine the presence of data for that UE in the unused resources960.

A fallback mechanism is provided for conditions in which a UE is configured to support group-common PDCCH, but did not receive a group-common PDCCH. For example, UE804-1did not successfully detect the group-common PDCCH in group-control slot810-10. The group-common PDCCH that was unsuccessfully detected may have indicated that a slot configuration was changed or that URLLC data was present in a previous slot when a puncture did in fact occur.

Without access to the information in the unsuccessfully detected group-common PDCCH, UE804-1does not assume that the configuration of slots received following the unsuccessfully detected group-common PDCCH are unchanged. Thus, UE804-1does not know the slot type of each slot810. Thus, UE804-1monitors PDCCH for each slot810to determine the slot type.

Furthermore, when eMBB data are unsuccessfully decoded, UE804-1should not assume the existence of URLLC data. Rather, UE804-1may consider different possibilities for the unsuccessful decoding of the eMBB data, such as noise, interference, puncture by URLLC data, etc.

A second fallback mechanism is needed for conditions in which a UE, such as UE804-1is not configured to detect or decode a GC-PDCCH. UE804-1determines whether slot configurations are being provided from higher layers. If there are no slot configurations provided from higher layers, UE804-1monitors PDCCH in each slot810, including DL and UL slots.

If there are slot configurations provided from higher layers, then UE804-1uses those slot configurations from the higher layers to determine which slots are UL slots and which slots are DL slots. UE804-1can also monitor UE specific PDCCH in each slot to determine slot type, etc.

Additionally, when UE804-1is not configured to detect or decode a GC-PDCCH, UE804-1is not able to perform PDCCH resource sharing using a resource allocation indication provided in a GC-PDCCH as described above. Rather, UE804-1determines whether resources are being shared using techniques that do not rely on GC-PDCCH. Additionally, since puncture information is not available for URLLC data directed to another UE, such as UE804-2or804-3, UE804-1assumes that eMBB data is not punctured by URLLC data. In this case, UE804-1may need to consider different possibilities for the unsuccessful decoding of the eMBB, such as noise, interference, puncture by URLLC data, etc.

FIGS. 10A-10Care a flowchart1000of a method (process) of wireless communication of a UE. The method is performed by a UE, such as UE804-1of a group of UEs804-1,804-2, . . .804-G, apparatus1102, and apparatus1102′. As shown inFIG. 10A, at operation1002, UE804-1receives symbols in a first time slot having a control region and a data region. At operation1004, UE804-1determines whether it is configured to detect a GC downlink control channel. If UE804-1determines that it is not configured to detect a GC downlink control channel, then the method continues at operation1080shown inFIG. 10C. If UE804-1determines that it is configured to detect a GC downlink control channel, then the method continues at operation1006shown inFIG. 10A.

At operation1006UE804-1attempts to detect a GC down link control channel carried by the received symbols and directed to UE804-1's group of UEs. At operation1008, UE804-1determines whether the detection of the GC downlink control channel was successful.

If UE804-1determines that the detection was not successful, then the method continues at operation1010. At operation1010UE804-1iteratively decodes a UE specific down link control channel in each of the first time slot and subsequent time slots, after which the determination at operation1008is performed again to determine whether the detection of the GC down link control channel was successful, forming a logical loop. This loop can continue until the804-1successfully detects a GC down link control channel in a time slot.

Once UE804-1determines that the detection was successful, then the method continues with UE804-1performing at least one of operations1012followed by operation1020(shown inFIG. 10B), operation1014followed by operation1050(shown inFIG. 10C),1016followed by operation1070(shown inFIG. 10C), and operation1018.

At operation1012, UE804-1determines, based on common information in the GC downlink control channel, a first slot configuration of one or more time slots. Next, at operation1020(ofFIG. 10B), UE804-1determines that each of the one or more time slots is an up-link time slot or a down-link time slot based on the first slot configuration. Next, the method continues at one or more of operations1022,1030,1034,1040, and1046ofFIG. 10B. In other words, UE804-1can perform one or more of these operations.

At operation1022, UE804-1determines based on the first slot configuration, that a third time slot of the one or more time slots is changed from a down-link time slot to an up-link time slot allocated to another UE of the group of UEs. Next, the method continues at one or more of operations1024,1026, and1028. At operation1024, UE804-1refrains from decoding a UE specific down link control channel of the third time slot. At operation1026, UE804-1refrains from conducting a RRM measurement in the third time slot. At operation1028, UE804-1refrains from conducting a CSI measurement in the third time slot.

At operation1030(FIG. 10B) (following operation1012ofFIG. 10A), UE804-1performs a first channel-state information measurement in time slots of the one or more time slots that are designated for down-link time slots semi-statically. At operation1032, UE804-1performs a second channel-state information measurement in time slots of the one or more time slots that are designated for down-link time slots dynamically in accordance with the first slot configuration.

At operation1034, UE804-1performs a first power control in time slots of the one or more time slots that are designated for up-link time slots semi-statically. At operation1036, UE804-1performs a second power control in time slots of the one or more time slots that are designated for up-link time slots dynamically in accordance with the first slot configuration.

At operation1040, the first slot configuration can indicate whether the time slot is an up-link time slot, a down-link time slot, an up-link priority bi-directional time slot, or a down-link priority bi-directional time slot. UE804-1can further determine, based on whether the time slot is an up-link time slot, a down-link time slot, an up-link priority bi-directional time slot, or a down-link priority bi-directional time slot, a detection period for performing an energy detection for CCA in each time slot. Next, the method continues at one or more of operations1042and1044. At operation1042, UE804-1determines a symbol period designated for transmitting a predetermined tone used for CCA in the detection period based on whether the time slot is an up-link time slot, a down-link time slot, an up-link priority bi-directional time slot, or a down-link priority bi-directional time slot. At operation1044, the UE-804-1determines an energy detection threshold used for CCA whether the time slot is an up-link time slot, a down-link time slot, an up-link priority bi-directional time slot, or a down-link priority bi-directional time slot.

At operation1046(seeFIG. 10B), UE804-1determines a gap period in the first time slot based on the first slot configuration.

At operation1014(ofFIG. 10A), UE804-1determines based on common information in the GC downlink control channel, a puncture configuration indicating one or more punctured symbols received in a second time slot. Next, at operation1050(ofFIG. 10C), UE804-1detects a start of a down-link transmission on the unlicensed link.

The method can continue at operation1052or at operation1056. At operation1052, UE804-1determines that a particular time slot is within the transmission burst duration from the start. At operation1054, UE804-1demodulates symbols received in the particular time slot. At operation1056, UE804-1selects a time point within the transmission burst duration from the start. At operation1058, UE804-1performs, at the time point, an LBT operation without random backoff. At operation1060, UE804-1transmits data in an up-link on the unlicensed link when the unlicensed link is determined to be clear by the LBT operation.

At operation1016(ofFIG. 10A), UE804-1determines based on common information in the GC downlink control channel, a transmission burst duration of a transmission on an unlicensed link. Next, at operation1070(ofFIG. 10C), UE804-1determines that data carried by one or more symbols in the second time slot were not successfully decoded. At operation1072, UE804-1decodes data carried by symbols other than the punctured symbols in the second time slot again or sends a negative acknowledgement.

At operation1018, UE804-1determines based on common information in the GC downlink control channel, one or more sub-regions of the control region containing one or more of the received symbols that are a part of a down link data channel.

At operation1080(ofFIG. 10C), which is performed when it is determined that UE804-1is not configured to detect a GC downlink control channel, UE804-1determines whether a second slot configuration of the one or more time slots is received from a layer above a physical layer. When the second slot configuration is received, at operation1082UE804-1determines each of the one or more time slots is an up-link time slot or a down-link time slot based on the second slot configuration. At operation1084, UE804-1decodes a UE specific down link control channel in the each time slot determined to be a down-link time slot. At operation1086, UE804-1determines the each time slot is an uplink time slot or a downlink time slot based on the decoded UE specific downlink control channel of the each time slot. This decoding operation can be performed, regardless of whether the time slot is a DL or UL time slot.

FIG. 11is a conceptual data flow diagram1100illustrating the data flow between different components/means in an exemplary apparatus1102. The apparatus1102may be a UE of a group of UEs. The apparatus1102includes a reception component1104, a decoder1106, a control implementation component1108, a transmission component1110, a DL control channel component (GC and UE specific)1112, and a channel detection component1114. The reception component1104may receive transmission signals1162including symbols in a first time slot having a control region and a data region.

In one aspect, when configured for detection of a GC DL control channel, the GC channel detection component1114attempts to detect a GC DL control channel carried by the received symbols and directed to the UE's group of UEs. The GC DL control channel contains common information directed to the group of UEs. Once the attempted detection by the GC channel detection component1114is successful, the DL control channel component1112determines based on the common information at least one of a first slot configuration of one or more time slots, a puncture configuration indicating one or more punctured symbols received in a second time slot, a transmission burst duration of a transmission on an unlicensed link, and one or more sub-regions of the control region containing one or more of the received symbols that are a part of a down link data channel.

In certain configurations, when the GC channel detection component1114is not configured to detect a GC DL control channel, the DL control channel component1112determines whether a second slot configuration of the one or more time slots is received from a layer above a physical layer. When the second slot configuration is received, the DL control channel component determines each of the one or more time slots is an up-link time slot or a down-link time slot based on the second slot configuration and the decoder1106decodes a UE specific down link control channel in the each time slot determined to be a down-link time slot.

In certain configurations, when the second slot configuration is received, the decoder1106decodes a UE specific down link control channel in the each time slot. This decoding operation can be performed, regardless of whether the time slot is a DL or UL time slot. The DL control channel component1112determines the each time slot is an uplink time slot or a downlink time slot based on the decoded UE specific downlink control channel of the each time slot.

In certain configurations, when the attempted downlink control channel was not detected successfully, the GC channel detection component1114continues to attempting to detect a group common down link control channel in a subsequent time slot until detection is successful.

In certain configurations, when the DL control channel component1112determines, based on the common information, a first slot configuration of one or more time slots, the DL control channel component1112determines that each of the one or more time slots is an up-link time slot or a down-link time slot based on the first slot configuration.

Next, in certain configurations, based on the first slot configuration, the DL control channel component1112can determine that a third time slot of the one or more time slots is changed from a down-link time slot to an up-link time slot allocated to another UE of the group of UEs. Based on the determination that the third time slot is changed to an up-link time slot, the decoder1106can refrain from decoding a UE specific down link control channel of the third time slot, the control implementation component1108can control the UE to refrain from conducting an RRM measurement in the third time slot, and/or the control implementation component1108can control the UE to refrain from conducting a CSI measurement in the third time slot.

In certain configurations, based on the first slot configuration, the control implementation component1108can control the UE to perform a first channel-state information measurement in time slots of the one or more time slots that are designated for down-link time slots semi-statically, and a second channel-state information measurement in time slots of the one or more time slots that are designated for down-link time slots dynamically in accordance with the first slot configuration.

In certain configurations, based on the first slot configuration, the control implementation component1108can control the UE to perform a first power control in time slots of the one or more time slots that are designated for up-link time slots semi-statically, and a second power control in time slots of the one or more time slots that are designated for up-link time slots dynamically in accordance with the first slot configuration.

In certain configurations, the first slot configuration indicates whether the corresponding time slot is an up-link time slot, a down-link time slot, an up-link priority bi-directional time slot, or a down-link priority bi-directional time slot. The DL control channel component1112can determine a detection period for performing an energy detection for CCA in each time slot based on whether the time slot is an up-link time slot, a down-link time slot, an up-link priority bi-directional time slot, or a down-link priority bi-directional time slot. Additionally, in certain configurations, based on whether the time slot is an up-link time slot, a down-link time slot, an up-link priority bi-directional time slot, or a down-link priority bi-directional time slot, the DL control channel component1112can determine a symbol period designated for transmitting a predetermined tone used for CCA in the detection period. Additionally or alternatively, the DL control channel component1112can determine an energy detection threshold used for CCA based on whether the time slot is an up-link time slot, a down-link time slot, an up-link priority bi-directional time slot, or a down-link priority bi-directional time slot.

In certain configurations, based on the first slot configuration, the DL control channel component1112determines a gap period in the first time slot.

In certain configurations, the DL control channel component1112determines, based on the common information, a puncture configuration indicating one or more punctured symbols received in a second time slot. The channel detection component1114detects a start of a down-link transmission on the unlicensed link. The DL control channel component1112determines that a particular time slot is within the transmission burst duration from the start. The demodulator component1124demodulates symbols received in the particular time slot.

In certain configurations, when the DL control channel component1112determines, based on the common information, a transmission burst duration of a transmission on an unlicensed link. The DL control channel component1112selects a time point within the transmission burst duration from the start of a down-link transmission on the unlicensed link. The transmission component1110performs an LBT operation without random backoff at the time point. The transmission component1110transmits data in an up-link on the unlicensed link when the unlicensed link is determined to be clear by the LBT operation.

In certain configurations, when the DL control channel component1112determines, based on the common information, a puncture configuration indicating one or more punctured symbols received in a second time slot, the DL control channel component1112determines that data carried by one or more symbols in the second time slot were not successfully decoded. The decoder1106decodes data carried by symbols other than the punctured symbols in the second time slot again or sends a negative acknowledgement.

FIG. 12is a diagram1200illustrating an example of a hardware implementation for an apparatus1102′ employing a processing system1214. The processing system1214may be implemented with a bus architecture, represented generally by a bus1224. The bus1224may include any number of interconnecting buses and bridges depending on the specific application of the processing system1214and the overall design constraints. The bus1224links together various circuits including one or more processors and/or hardware components, represented by one or more processors1204, the reception component1104, the decoder1106, the control implementation component1108, the transmission component1110, the DL control channel component (GC and UE specific)1112, the channel detection component1114, and a computer-readable medium/memory1206. The bus1224may also link various other circuits such as timing sources, peripherals, voltage regulators, and power management circuits, etc.

The processing system1214may be coupled to a transceiver1210, which may be one or more of the transceivers354. The transceiver1210is coupled to one or more antennas1220, which may be the communication antennas352.

The transceiver1210provides a means for communicating with various other apparatus over a transmission medium. The transceiver1210receives a signal from the one or more antennas1220, extracts information from the received signal, and provides the extracted information to the processing system1214, specifically the reception component1104. In addition, the transceiver1210receives information from the processing system1214, specifically the transmission component1110, and based on the received information, generates a signal to be applied to the one or more antennas1220.

The processing system1214includes one or more processors1204coupled to a computer-readable medium/memory1206. The one or more processors1204are responsible for general processing, including the execution of software stored on the computer-readable medium/memory1206. The software, when executed by the one or more processors1204, causes the processing system1214to perform the various functions described supra for any particular apparatus. The computer-readable medium/memory1206may also be used for storing data that is manipulated by the one or more processors1204when executing software. The processing system1214further includes at least one of the reception component1104, the decoder1106, the control implementation component1108, the transmission component1110, the DL control channel component1112, and the channel detection component1114. The components may be software components running in the one or more processors1204, resident/stored in the computer readable medium/memory1206, one or more hardware components coupled to the one or more processors1204, or some combination thereof. The processing system1214may be a component of the UE350and may include the memory360and/or at least one of the TX processor368, the RX processor356, and the communication processor359.

In one configuration, the apparatus1102/apparatus1102′ for wireless communication includes means for performing each of the operations ofFIGS. 10A-10C. The aforementioned means may be one or more of the aforementioned components of the apparatus1102and/or the processing system1214of the apparatus1102′ configured to perform the functions recited by the aforementioned means. As described supra, the processing system1214may include the TX Processor368, the RX Processor356, and the communication processor359. As such, in one configuration, the aforementioned means may be the TX Processor368, the RX Processor356, and the communication processor359configured to perform the functions recited by the aforementioned means.