Patent Application
20240015760
This disclosure pertains to the operation of wireless of networks such as those described in 3GPP TS 38.214, Physical layer procedures for data (Release 16), V16.2.0 and 3GPP TS 38.213, Physical layer procedures for control (Release 16), V16.2.0, for example.
Configured uplink and/or downlink grants may be managed by providing configuration parameters through higher layer signaling and then activating and/or deactivating use of provided configurations through group common PDCCH signalling that is transmitted to multiple UEs simultaneously. Similarly, enhancements to group common PDCCH signalling may be used to achieve dynamic scheduling.
DCI may be multiplexed (piggybacked) on anchor PDSCH by, for example informing the UE about which PDSCH can be considered as an anchor PDSCH and expected to carry piggybacked DCI. The UE can inherit some configurations of the anchor PDSCH to reduce the size of piggybacked DCI.
Triggering of aperiodic CSI reports for a group of UEs may be enabled, for example, via a CSI request field in GC-PDCCH to trigger aperiodic CSI and provide the PUSCH grant to different UEs to transmit their report.
Deactivation and/or activation of semi-persistent CSI reports for a group of UEs may also be enabled via a CSI request field in GC-PDCCH. Control fields of GC-PDCCH may be used to indicate whether GC-PDCCH is used for activation or deactivation of semi-persistent CSI report.
This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. Furthermore, the claimed subject matter is not limited to limitations that solve any or all disadvantages noted in any part of this disclosure.
Table 15 of the Appendix describes many of the acronyms used herein.
Configured Grant in NR
In NR Rel. 15/16, configured uplink (UL) grant type 2 and semi-persistent scheduling (SPS) downlink (DL) can be deactivated and/or activated by use equipment (UE)-specific PDCCH which is validated as follows. The cyclic redundancy check (CRC) of a corresponding DL control information (DCI) format is scrambled with a CS-RNTI provided by cs-RNTI, and the NDI field in the DCI format for the enabled transport block is set to ‘0’. The DFI flag field, if present, in the DCI format is set to ‘0’. If validation is for scheduling activation and if the physical downlink shared channel (PDSCH)-to-hybrid automatic repeat request (HARQ) feedback timing indicator field in the DCI format is present, the PDSCH-to-HARQ feedback timing indicator field does not provide an inapplicable value from dl-DataToUL-ACK.
See 3GPP TS 38.213, Physical layer procedures for control (Release 16), V16.2.0.
If the UE is provided with a single UL configured grant (CG) type 2 or DL SPS, then activation DCI is shown in Table 1 of the Appendix.
If the UE is provided with a single UL CG type 2 or DL SPS, then deactivation DCI is shown in Table 2 of the Appendix.
If the UE is provided with multiple UL CG type 2 or DL SPS, then the value of HARQ field indicates index of activated grant provided by Configuredgrantconfig-index or by SPSconfig-index. In this case, the activation DCI is shown in Table 3 of the Appendix.
If the UE is provided with multiple configurations for UL CG Type 2 or DL SPS, and the UE is provided by Type2Configuredgrantconfig-ReleaseStateList or SPS-ReleaseStateList, a value of the HARQ field indicates a corresponding entry for scheduling release of one or more UL grant Type 2 PUSCH or SPS PDSCH configurations. If the radio resource control (RRC) lists are not provided, then the value HARQ field indicates the index of the released grant. In this case, the deactivation DCI is shown in Table 4 of the Appendix.
It is expected that many reduced capability NR devices may need to cooperate to accomplish certain task. For example, several cameras may need to upload the live captured videos to cooperatively provide the controller with an idea about the monitored area, traffic, etc. In this example, the controller transmits simultaneous triggers/activations which enables the cameras to upload/transmit such videos to the controller. Another use case is that several actuators may need to receive different messages simultaneously and synchronously to cooperatively accomplish one task, e.g., printing machine, rotating pars of machines, etc. In this use case, the controller simultaneously transmits such messages to the actuators. Therefore, relying on UE-specific signaling to deactivate and/or activate or trigger or schedule any DL or UL transmission would consume more resources due to signaling overhead, especially in the case of large number of devices and/or UEs. This could result in decreased spectral efficiency of system. For example, using UE-specific physical downlink control channel (PDCCH) to deactivate and/or activate uplink (UL) configured grant Type 2 or Semi-Persistent Scheduling downlink (SPS-DL) of individual UEs results in a waste of resources, if we know a-priori that those UEs need to receive the deactivation and/or activation commands at the same time. Similarly, triggering aperiodic or deactivating and/or activating semi-persistent channel state information (CSI) reporting through UE-specific PDCCH would consume many of the available control channel elements (CCEs) if such process is done for many UEs. Therefore, we need to develop solutions to overcome such issues when dealing with many UEs.
Although the solutions described herein target reduced capability NR devices, these solutions may be used with other devices such as legacy UEs, regular UEs, and non-reduced capability NR devices as well, for example.
Throughout this disclosure, the term “UE-specific PDCCH” refers to the PDCCH that is transmitted in a UE-specific search space and the term “group-common PDCCH” refers to the PDCCH that is transmitted in a common search space. Please note that “UE-specific” and “UE-dedicated” are used interchangeably throughout the disclosure.
While enhancements for GC-PDCCH may be used to provide dynamic grants or deactivate and/or to activate semi-persistent scheduling, it will be appreciated that solutions may be created using Medium Access Control-Control Element (MAC-CE) technology. For example, GC-PDCCH/UE-specific PDCCH may schedule MAC-CE to realize the same functionalities of the GC-PDCCH described herein. The fields of MAC-CE may be similar to the designed control fields of GC-PDCCH.
New Type of Configured Scheduling
To cope with the overhead associated with using UE-specific PDCCH to deactivate and/or activate UL configured grant Type 2 or SPS DL, we introduce new types of configured scheduling for both DL and UL that may be deactivated and/or activated for a group of UE simultaneously. Herein we may refer to downlink configured scheduling as as SPS-DL Type 2 and uplink configured scheduling as UL CG Type 3.
As a potential enhancement, the gNB may configure reduced capability new radio (NR) devices with all the parameters applied for the DL or UL transmission through higher layer signaling, e.g. RRC information element (IE) SPS-Config-RedCap and ConfiguredGrantConfig-RedCap, respectively, that can be either UE-specific RRC configurations transmitted through UE-specific signaling or group-common RRC configurations transmitted through broadcast/groupcast signaling, or through a combination of RRC+MAC-CE. For group common RRC configuration, the same RRC configuration could be transmitted to a group of UEs and could be activated or deactivated via a group common DCI carried in group common PDCCH. Once gNB provides the UE with the configurations of the DL/UL configured scheduling, gNB may deactivate and/or activate the grant through group-common PDCCH. gNB could configure same or common RRC configuration for a group of UEs via either individual UE-specific RRC or common signaling such as system information or the like.
Alternatively, gNB may transmit the deactivation command through UE-specific PDCCH to the individual UEs that did not provide ACK to the deactivation command transmitted on GC-PDCCH. Those UEs are expected to transmit ACK to the deactivation command transmitted through UE-specific PDCCH.
As yet another possibility, if the UE transmits ACK to deactivation command, but it received the “N” deactivation commands through GC-PDCCH after the ACK transmission, then UE may transmit ACK again. This may be beneficial if gNB did not receive the earlier ACK transmitted by the UE. The value of N may be predefined (provided in the specs) or configured through higher layer signaling.
For UL CG Type 3, an exemplary signaling diagram is shown in
Alternatively, gNB may transmit the deactivation command through UE-specific PDCCH to the individual UEs that did not provide ACK to the deactivation command transmitted on GC-PDCCH. Those UEs are expected to transmit ACK to the deactivation command transmitted through UE-specific PDCCH.
As yet another possibility, if the UE transmits ACK to deactivation command, but it received the “N” deactivation commands through GC-PDCCH after the ACK transmission, then UE may transmit ACK again. This may be beneficial if gNB did not receive the earlier ACK transmitted by the UE. The value of N may be predefined (provided in the specs) or configured through higher layer signaling.
Though the exemplary signaling diagrams in
The higher layer signaling to configure SPS-DL Type 2, e.g., SPS-Config-RedCap, may use SPS-Config for configuring the legacy DL semi-persistent transmission as a baseline with additional parameters as shown in Code Example 1 of the Appendix. The newly introduced parameters are described in Table 5 of the Appendix.
For UL CG Type 3, gNB may use higher layer signaling similar to ConfiguredGrantConfig and/or rrc-ConfiguredUplinkGrant to provide the UE with the needed configurations. However, the UE needs to distinguish between UL CG Type 1 and UL CG Type 3. To address this, the gNB may use higher layer signaling for this purpose, e.g., RRC parameter such as GrantType, as shown Code Example 2 of the Appendix. If GrantType is set to ULCGType1, the UE shall assume that gNB configures legacy UL CG Type 1, that is just configured through RRC, no activation DCI is needed. On the other hand, if GrantType is set to UL CG Type3, the UE shall assume that gNB provides all the configurations of configured grant UL through RRC, but the gNB activates it through DCI.
To deactivate and/or activate the configured grants for different UEs, e.g., DL-SPS Type 2 or UL CG Type 3, gNB may use GC-PDCCH to deactivate and/or activate them for group of UEs at the same time. This is beneficial to reduce the number of needed UE-specific PDCCH that gNB needs to transmit to deactivation and/or activation command to each UE individually. Moreover, with most of the parameters of DL-SPS Type 2 or UL CG Type 3 are configured through higher layer signaling, the size of GC-PDCCH is expected to be small.
Assuming that each UE in a particular group is configured with just single DL-SPS Type 2 and/or UL CG Type 3 and the grants of those UEs are deactivated and/or activated simultaneously, gNB may transmit GC-PDCCH scrambled with a new RNTI that can be configured by higher layer signaling, such as RRC parameter CG-RNTI-r17, to deactivate and/or activate DL-SPS Type 2 or UL CG Type 3 for this group of UEs. Table 6 of the Appendix is an example of DCI that may be used to deactivate and/or activate DL-SPS Type 2 or UL CG Type 3.
Since gNB uses this GC-PDCCH for both activation and deactivation of the DL-SPS Type2 or UL CG Type 3, “DL/UL Indicator” points whether this DCI carries command related to DL-SPS Type 2 or UL CG Type 3. For example, if “DL/UL Indicator” is set to 1, DCI carries command for DL-SPS Type 2. On the other hand, when it is set to 0, DCI carries command for UL CG Type 3. However, if gNB configures the UE with either DL CG or UL CG, but not both, the UE may ignore the value provided by “DL/UL Indicator” field. In this case, the received activation or deactivation command is applied to the configured grant which can be either DL CG or UL CG.
The “Activation Indicator” field indicates whether the configured grant is activated or not. If it is set to 1, the DL/UL configured grant is activated based on “DL/UL Indicator”. However, if it is set to zero, then UE may ignore it and should not interpret as deactivation command. The deactivation carried by another field, “Deactivation Indicator” which is set one to indicate deactivation of already activated grant.
The “Activation Indicator” and “Deactivation Indicator” fields are mutually exclusive fields, i.e., the UE does not expect both fields to be set to 0/1 simultaneously. However, UE may receive multiple GC-PDCCH with either “Activation Indicator” or “Deactivation Indicator” is set to 1, as shown in
Instead of having two fields for activation and deactivation of configured UL/DL grant, one field may be used for both activation and deactivation based on whether this field is toggled or not. The bit width of this field is one field. For example, if the UL CG Type 3 or DL-SPS Type 2 is active and UE receives GC-PDCCH with toggled field, then the UE may assume that UC CG Type 3 or DL-SPS Type 2 is deactivated. UE determines whether this indication is for deactivation and/or activation of DL or UL configured grant using DL/UL Indicator field. As another possibility, this one-bit field may use predefined (provided in the specs) to activate or deactivate configured UL/DL grant. For example, if the one-bit field is set to “1”, then the configured DL/UL grant is activated and if it is set to “0”, then the configured DL/UL grant is deactivated.
Instead of having a dedicated field to indicate whether deactivation and/or activation command is for DL-SPS Type 2 or UL CG Type 3, i.e., DL/UL Indicator field, other methods may be used. For example, different RNTIs may be dedicated for deactivation and/or activation of the configured DL/UL grants which may be configured by higher layer signaling such as RRC parameters de-activation-RNTI-DL and de-activation-RNTI-UL, respectively. Also, the configurations of monitoring search space sets or control resource set (CORESET) may indicate whether the transmitted GC-PDCCH is for DL or UL configured grant deactivation and/or activation. Higher layer signaling may carry this indication such as RRC parameter usage that may be set to ENUMERATED {DL-SPSType2, ULCGType3} in the configurations of either the CORESET or the search space sets.
Moreover, instead of configuring the offset of the configured UL or DL grant through higher layer signaling, the DCI in GC-PDCCH may carry the time offset as shown Table 7 of the Appendix with additional field “Time Offset Indicator” for example. This field may point to one of a plurality of offset values that may configured through higher layer signaling such as RRC or RRC+MAC-CE. Here, different UEs in the group may be configured with different offset values so that the same indicated value (codepoint) in the DCI maps to different offset values. Though the bit width of this field is fixed in Table 7, in general it may vary and depend on the number of configured time offset values, e.g., the bit width may be equal to log2(number of time offset values). The time may be from particular SFN/slot. For example, it may be applied from the SFN/slot that carries PDCCH or other SFN/slot configured by timeDomainReference.
Since the Time Offset Indicator field is commonly signaled to all UEs addressed by GC-PDCCH, then the same time offset may be applied as shown in
In general, gNB may configure reduced capability NR device with multiple DL-SPS Type 2 and UL CG Type 3 grants. To address this, the GC-PDCCH may indicate the index of deactivated and/or activated grant. As one alternative, GC-PDCCH may carry additional field to indicate the index of deactivated and/or activated grant which is shared by all UE receiving this GC-PDCCH. Table 8 of the Appendix shows an example of the fields of GC-PDCCH which has Grant Index field to indicate which DL/UL grant is deactivated and/or activated. Other fields are similar to the depicted ones in the previous examples.
For the size of Grant Index field, gNB may configure it by higher layer signaling such as RRC. Alternatively, or when such configuration is absent, UE may derive the size based on the number of configured DL/UL grants. For example, if the GC-PDCCH is for deactivation and/or activation of DL or UL grants, then the bit width of Grant Index field is given by log2(number of DL grants) or log2(number of UL grants), respectively. In this case, Grant Index field indicates the index of the DL/UL grant to be deactivated and/or activated.
Moreover, the bit width of Grant Index field may be equal to the number of configured DL/UL grants which is beneficial for deactivation and/or activation of multiple grants at the same time. For example, the most significant (left) bit represents the configured DL/UL grant with the highest index, and the second most significant (left) bit represents the configured DL/UL grant with the second highest index and so on. If the bit width of Grant Index is more than the number of configured DL/UL grant, then some bits are not mapped to any grant. For example, remaining least significant bits are not mapped to any grant.
Also, gNB may configure the UE with a list of multiple configured DL/UL grants where each one or subset of them is associated with a particular grant index through higher layer signaling. In this case, the Grant Index field in DCI payload of GC-PDCCH may indicate one or multiple configured DL/UL grants to be deactivated and/or activated. The bit width of the Grant Index field may be equal to loge (the list size) or equal to the list size itself where may deactivate and/or activate multiple grant at the same time.
As yet another solution, gNB may transmit multiple Grant Index fields to each UE or sub-group of UEs through GC-PDCCH. This is beneficial because gNB can indicate different configured DL/UL grant indices to different UEs or sub-group of UEs within the same GC-PDCCH. Other fields may be shared between all the UEs receiving GC-PDCCH such as DL/UL Indicator field, Activation Indicator field, and Deactivation Indictor field for example. Table 9 of the Appendix shows an example of GC-PDCCH fields.
Each UE or sub-group of UEs needs to know which field carries the indices of the deactivated and/or activated DL/UL grants. Therefore, gNB may configure the UE or sub-group of UEs information about the location of the field in GC-PDCCH that the UE should consider. For example, gNB may transmit higher layer signaling such as RRC parameter Grant_positionInDCI to point to the start position of Grant Index_m, m∈{0, 1, . . . , N}, within the DCI payload of GC-PDCCH. The bit width of Grant Index_m may indicated/derived as described above, or it may be predefined e.g., provided in the specs. Moreover, gNB may provide the UE with the total length of the DCI payload through higher layer signaling such as RRC parameter CG DCI PayloadSize. One value (codepoint) of the Grant Index_m field may be reserved to indicate no change (activation or deactivation) should be applied by the UEs or the sub-group of UEs that monitor Grant Index_m. For example, all zeros or all ones may be used. This approach may be beneficial if gNB needs to activate or deactivate the grant of particular sub-group while keep the remaining sub-groups without any changes.
Moreover, other fields may be as DL/UL Indicator field, Activation Indicator field, and Deactivation Indictor field for example may separately for each UE or sub-group of UEs. For example, through the same GC-PDCCH, gNB may activate the configured DL/UL grant for some UEs while deactivating the configured grant for another set of UEs. Table 10 of the Appendix shows an example of DCI payload of GC-PDCCH where dedicated activation and deactivation indicator fields for each UE or sub-group of UEs. Specifically, each Grant Index field is associated with dedicated activation and deactivation fields. The position of Grant Index fields may be indicated as described above. The position of the dedicated activation and deactivation fields in the DCI may be indicated in as same as the position of Grant Index field through higher layer signaling. Alternatively, UE may derive their positions based on the position of Grant Index field. For example, the position of the activation and deactivation fields may be two bits before the beginning of Grant Index as illustrated in Table 10.
Alternatively, the Activation Indicator and Deactivator Indicator fields may for different UEs or sub-group of UEs may be occupy consecutive bits as shown in Table 11 of the Appendix. To let the UE know the position of the associated (De)Activation Indicator fields in DCI payload of GC-PDCCH, gNB may configure the UE with their position in DCI through higher layer signaling such as (De)ActivationfiositionInDCI. It may be enough that gNB just point the position of one field (Activation Indicator or Deactivation Indicator) and UE may derive the relative position of
The second field (Deactivation Indicator or Activation Indicator, respectively). For example, it may occupy the consecutive bit. Attentively, gNB may configure the UE with its index or the sub-group index through higher layer signaling which allows the UE to know the position of its associated bit within the DCI payload as shown in Table 11 for example. For the position of Grant Index, it may be provided as described above. As another alternative, gNB may configure the UE with size of Grant Index which may be the same for all Grant Index_m, m E {0, 1, . . . , N}, through higher layer signaling. Then UE may use information about the configured UE index or sub-group index and the size of Grant Index field to derive the position of the field with the DCI payload. In other words, the DCI payload of GC-PDCCH is divided into blocks based on the configured UE index or sub-group index. Therefore, once the UE knows its index, the UE can allocate relavant fields in the DCI payload.
Though in the previous examples of Activation Indicator and Deactivation Indicator fields are part of the DCI payload of GC-PDCCH, it is also possible to replace both fields with just one field. When this field is toggled, then UE may assume that status (active or not active) of the configured grant is toggled as described above in more details. Or as another alternative, the one-field may use configured or predefined (provided in the specs) to activate or deactivate configured UL/DL grant. For example, if the one-bit field is set to “1”, then the configured DL/UL grant is activated and if it is set to “0”, then the configured DL/UL grant is deactivated.
Instead of having fields to indicate the activation or deactivation of the configured grant, the scrambling RNTI may indicate whether this GC-PDCCH is for activation or deactivation. The gNB may configure the UE with activation RNTI and deactivation RNTI through higher layer signaling such as RRC parameter Activation-RNTI and deactivation-RNTI. GC-PDCCH may carry Grant Index field to indicate which CG is deactivated and/or activated. Also, different RNTIs may be used to indicate whether GC-PDCCH is for the uplink or downlink grant instead of using “DL/UL Indicator” field.
Though gNB may scramble CRC of GC-PDCCH with particular RNTI for different purposes as described above, gNB may still configure the UE with CS-RNTI through higher layer signaling. In this case, UE may interpret GC-PDCCH scrambled with CG-RNTI-r17, Activation-RNTI, de-activation-RNTI-DL de-activation-RNTI-UL, etc. is only for activation of configured DL/UL grant. However, for scheduling any retransmission, the PDCCH will be scrambled with CS-RNTI. In other words, PDCCH for the activation of DL/UL grant and PDCCH for scheduling retransmission are scrambled with different RNTI.
Instead of configuring CS-RNTI explicitly thorough higher layer signaling, UE may derive CS-RNTI based on its cell radio-network temporary identifier (C-RNTI) and RNTI used for activating DL/UL configured grant, e.g., DL-SPS Type 2 or UL CG Type 3. Some formulas may be used to derive CS-RNTI. For example, CS-RNTI=XOR (C-RNTI, CG-RNTI-r17).
For DL-SPS Type 2 and UL CG Type 3, the solutions described herein may also be applied for other enhancements of dynamic grant, configured DL/UL or trigger CSI report in this disclosure.
In an alternative embodiment, instead of having GC-PDCCH to activate DL-SPS Type 2, the PDSCH occasions may be activated automatically after receiving the RRC configurations by certain period. This period may be configurated through higher layer signaling or predefined (provided in the specs) which may be in absolute time, in units of orthogonal frequency division multiplexing (OFDM) symbols, slots, subframe, etc. With such information, UE knows the start of the first PDSCH occasion. The other aforementioned configurations such as periodicity and time/frequency domain resource allocation let the UE know the how many symbols are occupied and in which periodicity in which PDSCH occasion will be repeated.
Once such PDSCH occasions for DL-SPS are not needed, gNB may transmit UE-specific or group-common PDCCH to deactivate in any of the described ways throughout the disclosure or by other higher layer signaling such as RRC or RRC+MAC-CE.
As yet another possibility, UE may derive the monitoring occasions of PDSCH using some equations that may be function of its C-RNTI, ID, the ID of expected traffic, etc. For example, equations may be similar to the ones used to derive the monitoring occasion of paging PDCCH. However, these equations may be in determining the monitoring occasions for PDSCH reception itself rather than PDCCH as in paging.
Enhancement to Existing DL/UL Configured Grant
In NR Rel. 15-16, UL CG Type 2 and DL-SPS are deactivated and/or activated by UE-specific PDCCH which carries information about the time domain resource allocation, frequency domain resource allocation, MCS index, frequency hopping type, frequency hopping offset (for UL CG Type 2), etc. To address this, the gNB may transmit GC-PDCCH to simultaneously activate DL-SPS or UL CG Type 2 of a group of UEs where a set of the aforementioned parameters may be shared between those UEs.
Though the solutions described in this disclosure are presented for configured grant scheduling, they can be applied for dynamic grant scheduling as well.
As one alternative, GC-PDCCH may be have the fields similar to those in DCI format 0_0, 0_1, 0_2, 1_0, 1_1, or 1_2, but it is scrambled with another RNTI that gNB may configure through higher layer signaling. Some of those field may be applied by all UE receiving GC-PDCCH. For example, the “modulation and coding scheme” may be applied by all UEs receiving GC-PDCCH because, most likely, they experience comparable/similar channel conditions and the indicated MCS index should work for all of them.
Moreover, fields such as “time domain resource assignment (TDRA)” may be acceptable to be shared by all UE receiving because each UE will map the indicated value m provided by DCI payload in GC-PDCCH to row index m+1 in its own configured time domain resource allocation table provided in pdsch-Config for example. This is exemplified in
In general, this approach works well when the provided TDRA value in the DCI payload of GC-PDCCH maps to different time domain resources for different UEs based on the individually configured TDRA table for each UE. However, this may introduce some constraints on the scheduler to ensure that the indicated TDRA value always maps to non-overlapping resources in the time domain. To cope with this issue, the gNB may provide a set of UEs among those receiving GC-PDCCH with particular time offset to apply when they receive grant or activation command through GC-PDCCH. This offset may be configured through higher layer signaling such as RRC or RRC+MAC-CE. For the latter option, gNB may provide the UE with multiple offset values through RRC and then use MAC-CE to select which offset value to be applied. The offset value may be units of slot, OFDM symbol, etc. Please note that not all UEs receiving GC-PDCCH should be configured with an offset value, only a subset of them. Then the UE behavior depends on whether this parameter is configured or not as shown in the flow chart in
In step 1, UE receives PDCCH that provides dynamic grant or activates configured DL/UL grant. Then UE check whether the received PDCCH is a UE-specific PDCCH or GC-PDCCH as depicted in step 2. If it is a UE-specific PCDCCH (yes in step 2), then UE applies the legacy behavior in NR Rel. 15/16 to determine the time domain resources of dynamic/configured grant.
If the received grant or the activation command is received by GC-PDCCH (no in step 2) and the offset value is not provided (no is step 4), UE map the provided TDRA m value to row index m+1 in its own configured time domain resource allocation table, provided in pdsch-Config for example, to derive the location of the provided grant. Otherwise, if the received grant or the activation command is received by GC-PDCCH (no in step 2) and the offset value is provided (yes is step 4), UE map the provided TDRA m value to row index m+1 in its own configured time domain resource allocation table, provided in pdsch-Config for example, and then add the offset value to actual location of the grant.
As yet another option or possibility, gNB may provide the UE with another TDRA table that should be used when the grant or the activation command is provided through GC-PDCCH. For example, higher layer parameter such as pXsch-TimeDomainAllocationList-GroupScheduling-r17, X∈{d, u}, may be included in P XSCH-ConfigCommon or PXSCH-Config.
Moreover, gNB may provide the UE with an offset value through higher layer signaling. In this case, UE may apply this offset (as described above) on indicated time resource allocation provided by pdsch-TimeDomainAllocationList-GroupScheduling-r17.
Table 12 shows an example of which TDRA table that the UE should use when it receives dynamic grant or activation command through GC-PDCCH. In general, if gNB provides the UE with a dedicated TDRA table for such scheduling, the UE should apply it. Otherwise, UE may apply TDRA table used for grant provided/activated by UE-specific PDCCH.
Alternatively, the gNB may provide multiple TDRA value in DCI payload of GC-PDCCH to different UEs or sub-groups of UEs. Each one may apply the indicated TDRA by its corresponding TDRA field. To let the UE knows which TDRA field should be used, the gNB may configure the UE with location of its TDRA field withing GC-PDCCH. For example, higher layer signaling, such as RRC parameter TDRApositionInDCI for example, may point to the start position of TDRA field with the DCI payload of GC-PDCCH. The bit width of the TDRA field may be fixed and predefined e.g., provided in the specs, or it may be signaled through higher layer signaling such as RRC parameter TDRA size. Please note that other solutions described to Grant Index field in GC-PDCCH may be applied as well for the TDRA field.
As another solution to resolve the collisions between the grants provided by GC-PDCCH for different UEs is to allocate different frequency domain resources for each UE. Specifically, the same TDRA value may point to the same time domain resources for DL/UL grant for the UEs receiving the grant or the activation command through GC-PDCCH, but the grants may be frequency domain multiplexed (FDMed) as shown in
GC-PDCCH may provide the same frequency domain allocation through a single frequency domain resource assignment (FDRA) field as depicted in
The frequency offset value may be between the first RB indicated by FDRA and the first RB of the shifted location of PXSCH, where PXSCH is used for brevity and can correspond to PDSCH or physical uplink shared channel (PUSCH). The number of occupied RBs in all shifted location of PXSCH may be the indicated number of RBs indicated by FDRA field. In other words, the number of RBs of PXSCH for each UE is the same, but they are shifted by freq_offset. Though in
Alternatively, GC-PDCCH may provide multiple FDRA fields to different UEs or sub-groups of UEs to indicate different FDMed resources as shown in
In the example in
As yet another possibility, the DCI payload of GC-PDCCH may indicate a time-frequency resource block through TDRA/FDRA corresponding to the resource allocation for all UEs in the group. Each UE may figure out which RBs/symbols that are allocated to itself through a procedure involving e.g., the UE index within a group and a total number of UEs in group, or the UE index within a group and the number of RBs*symbols allocated to each UE in the group. By defining time-first or frequency-first UE mapping, the UEs could find their allocated resources for PXSCH.
To indicate whether GC-PDCCH activates or deactivates DL/UL configured grant, some of the aforementioned solutions may be applied such as introducing new fields to distinguish between different purposes of the GC-PDCCH. Also, other fields may be used to indicate which grant is deactivated and/or activated as shown in Table 13 of the Appendix for example. Or combination of different fields as in NR Rel. 15/16, such as HARQ process number field, redundancy version, modulation, and coding schemes, etc. See 3GPP TS 38.213.
Though gNB may scramble GC-PDCCH with particular RNTI for different purposes as described above, gNB may still configure the UE with CS-RNTI through higher layer signaling. In this case, UE may interpret GC-PDCCH scrambled with CG-RNTI-r17, Activation-RNTI, de-activation-RNTI-DL de-activation-RNTI-UL, etc. is only for deactivation and/or activation of configured DL/UL grant. However, for scheduling any retransmission, the PDCCH will be scrambled with CS-RNTI. In other words, PDCCH for the activation of DL/UL grant and PDCCH for scheduling retransmission are scrambled with different RNTI.
Instead of configuring CS-RNTI explicitly thorough higher layer signaling, UE may derive CS-RNTI based on its C-RNTI and RNTI used for activating DL/UL configured grant, e.g., DL-SPS or UL CG Type 2. Some formulas may be used to derive CS-RNTI. For example, CS-RNTI=XOR (C-RNTI, CG-RNTI-r17).
Piggybacked DCI
The gNB may exploit the transmission of a PDSCH to schedule another dynamic DL/UL grant or deactivate and/or activate another configured DL/UL, e.g., DL-SPS or UL CG type 2 trough transmitting a piggybacked DCI on this PDSCH. We label the PDSCH that carries the piggybacked DCI as the anchor PDSCH because it is used to schedule, activate, deactivate another DL/UL channel/signal by carrying DCI payload as shown in
Multiplexing DCI on PDSCH
The predefined (provided in specs) resource elements (REs) according to some rules within the anchor PDSCH may carry the piggybacked DCI.
As one alternative, the piggybacked DCI may occupy non-consecutive REs which may be in the available OFDM symbol after the first demodulation reference signal (DMRS) symbol(s) (either single-symbol DMRS or double-symbol DMRS) as shown in
The piggybacked DCI may occupy REs with the same subcarriers' indices as same as subcarriers' indices of REs carrying DMRS as shown on
Other mapping patterns may be applied as well such as every third, fourth, fifth, etc., RE carries piggybacked DCI. Or piggybacked DCI may occupy multiple consecutive REs similar to DMRS type 2. In general, the mapping pattern of the piggybacked DCI may be different than the mapping patterns of DMRS of the anchor PDSCH. For example, the mapping pattern of piggybacked DCI may follow the mapping pattern of DMR type. Or it may be different and gNB can provide it through higher layer signaling such as RRC parameter piggybacked_DCI_mapping_pattern.
Alternatively, gNB may map the piggyback DCI to REs with particular shift from the first subcarrier in anchor PDSCH.
As shown in
In one alternative, gNB may provide the UE the number of REs used to carry the piggybacked DCI through higher layer signaling. For example, gNB may provide the absolute number of REs that may carry piggybacked DCI or provide the percentage of total number of RBs/REs of the anchor PDSCH. Then UE apply the mapping pattern based on the number of REs that may carry the piggyback DCI.
As another alternative, UE may derive the number of REs to carry the piggybacked DCI. For example, gNB may provide the UE with the size of the piggybacked DCI through higher layer signaling such as RRC parameter DCI_piggybacked_size. Then based on the MCS index used for the anchor PDSCH, UE may derive how many REs are needed to carry the piggybacked DCI.
For example, similar to the parameters in BetaOffsets IE, e.g., betaOffsetACK-Index1, betaOffsetCSI-Part1-Index, etc., another RRC parameter such as betaOffsetDCI. The indicated value “m” by betaOffsetDCI may be mapped row “m+1” in table of possible beta offsets of DCI when it is multiplexed on PDSCH. Such tables may be predefined (provided in the specs) similar to the tables of beta offset in 3GPP TS 38.213. Alternatively, new tables may be introduced. Once the betaOffsetDCI is known to the UE, it may apply certain equations to derive the exact number of symbols that will carry the piggybacked DCI.
Moreover, higher layer signaling may indicate whether the betaOffsetDCI is statically indicated through RRC parameter or it may be indicated dynamically through PDCCH. In this case, a new DCI field in either UE-specific PDCCH or GC-PDCCH to point which betaOffsetDCI should be applied out of provided betaOffsetDCI values provided through higher layer signaling. Alternatively, UE may apply the first value among those values provided through higher layer signaling without any indicated in the PDCCH that schedule or activate the grant.
Though in the provided example, the piggybacked DCI is mapped to symbol after the DMRS symbol, piggybacked DCI may be mapped to other symbols within the anchor PDSCH. For example, the mapping may start from the first symbol of the anchor PDSCH as shown in
The REs within one OFDM symbol may not be enough to carry the piggybacked DCI on the anchor PDSCH depending on the applied mapping pattern. Therefore, multiple consecutive/non-consecutive OFDM symbols may be used to carry as shown in
Though in the previous example no piggybacked DCI is mapped to the REs within the DMRS symbol, i.e., no piggybacked DCI is mapped to the REs in the symbol carrying DMRS, in general, DMRS symbol may also be used to carry the piggybacked DCI as well.
Another alternative is to map the piggybacked DCI to consecutive REs as shown in
The number of consecutive REs in any OFDM symbol may be predefined (provided in the specs), or gNB may provide it to the UE through the higher layer signaling. For example, gNB may provide the UE with the absolute number of REs in the center of anchor PDSCH that may carry the piggybacked DCI through higher layer signaling such as num_center_REs_piggybackedDCI. Alternatively, gNB may provide the UE with number of REs for the piggybacked DCI by indicating it as a percentage of the total number of REs of the anchor PDSCH. This percentage may be provided through higher layer signaling, or by using a beta offset parameter to indicate the number of REs needed to carry the piggybacked DCI as described above.
UE may determine the total number of needed REs to carry the piggybacked DCI using one of the aforementioned procedures.
Though in the previous examples we show single symbol-symbol DMRS, the same procedures may be applied for double-symbol DMRS.
Monitoring Piggybacked DCI
The UE know may be informed in a number of ways regarding PDSCH may be considered as anchor PDSCH which can carry piggybacked DCI.
For example, the gNB may indicate to the UE whether DCI is multiplexed on PDSCH through higher layer signaling such as RRC parameter DCI-onPDSCH for example. Or, through RRC+MAC-CE to indicate whether PDSCH can carry piggybacked DCI or not. Also, RRC+MAC-CE may be used for semi-persistent indication where one MAC-CE indicates that PDSCH transmitted within particular time window may carry piggybacked DCI until the end of this window which is indicated by another MAC-CE.
For dynamic anchor PDSCH that is scheduled through UE-specific PDCCH, the scheduling PDCCH may carry an indication on whether anchor PDSCH carrying piggybacked. For example, a one-bit field in the scheduling PDCCH may be used for this purpose. This bit may be from the reserved bits on the scheduling DCI or purposing some of the existing bits if they are not needed for scheduling the anchor PDSCH.
For DL SPS, gNB may provide the UE with information on which SPS PDSCH may carry piggybacked DCI. In NR Rel. 15/16, gNB provides the UE with the periodicity of DL-SPS.
As one possibility, gNB may provide the UE with such information through higher layer signaling such as RRC parameter anchor-PDSCH. When anchor-PDSCH is set to 0.5, then every other SPS PDSCH may be used as anchor PDSCH as shown in
Alternatively, gNB may provide the UE with periodicity of the anchor PDSCH with the activated DL-SPS through higher layer signaling such as RRC parameter anchor-PDSCH-period starting from the first PDSCH SPS. The periodicity may in units of slot, OFDM symbol, absolute time, etc. In the example in
As yet another possibility, gNB may provide the UE with information about anchor PDSCH through RRC+MAC-CE, RRC+DCI, or RRC+MAC-CE+DCI. In the solution based on RRC+MAC-CE, gNB may have certain level of flexibility to update the periodicity of the anchor PDSCH, but this requires the decoding of PDSCH that carries MAC-CE. On the other hand, the solution based on RRC+DCI alleviates the need of MAC-CE by directly indicating the value through DCI which points to one value of multiple values configured through RRC at the cost of needing a dedicated control field in DCI format. The solution based on RRC+MAC-CE+DCI aims to achieve a balance between the aforementioned trade-offs. For example, gNB may provide the UE with multiple periodicity of the anchor PDSCH and then uses the activating PDCCH to indicate which periodicity is used in the activated DL-SPS.
The fields of the piggybacked DCI depend on its purpose. Therefore, the fields of the DCI payload of GC-PDCCH may also be the fields used for the piggybacked DCI. If the piggybacked DCI is used for both dynamic scheduling and configured grant, then additional one-bit field may be used for differentiation. Alternatively, gNB may indicate such information to the UE through higher layer signaling such as RRC parameter piggybacked-DCI-purpose which can indicate whether it will be used for dynamic grant or configured grant.
It may happen that for any anchor PDSCH, gNB does not need to transmit piggybacked DCI. To address this, a special indication to let the UE know that there is no piggybacked DCI is transmitted. As one alternative, gNB may transmit the piggybacked and set some fields to particular value. For example, all the fields of the piggybacked DCI may be set to all zeros.
As another alternative, special DMRS sequence, port, configuration, etc., may be used to indicate whether the anchor PDSCH carries piggybacked DCI or not. For example, if the legacy initialization sequence of DMRS may be used when anchor PDSCH carries piggybacked DCI. Another DMRS initialization sequence may be used to indicate that the anchor PDSCH does not carry piggybacked DCI. For additional DMRS initialization sequence associated with no piggybacked DCI, gNB may provide it to the UE through higher layer signaling such as RRC parameter piggybacked-DCI-ScramblingID.
For the anchor PDSCH that carried the piggybacked DCI, UE may assume that PDSCH is rate matched around the REs occupies by the piggybacked DCI. Or UE may assume that REs carrying PDSCH are punctured when they collide with REs supposed to carry piggybacked DCI.
Inheriting Anchor PDSCH Configurations
To reduce the overhead the piggybacked DCI and the number of needed REs within the anchor PDSCH, some of the configurations of the anchor PDSCH may be applied to the PXSCH that is scheduled/activated by piggybacked DCI.
As one possibility, UE may assume that MCS index of the anchor PDSCH is used for the scheduled PXSCH and hence the “modulation and coding scheme” is not needed to be indicated. In turn, this reduces the size of the piggybacked DCI.
Similarly, the TDRA or FDRA value of the anchor PDSCH may be applied for the scheduled/activated PXSCH. Which may further reduce the size of the piggybacked DCI.
The gNB may indicate to the UE which configurations are shared between the anchor PDSCH and the PXSCH that is scheduled/activated by the piggybacked DCI. This may be done through higher layer signaling such as RRC parameter shared-confs that may take values such as MCS, TDRA, FDRA, etc., or any combination of thereof.
Instead of introducing piggybacked DCI, new DCI formats may be used that have smaller size than DCI formats in NR Rel. 15/16 to schedule or provide deactivation and/or activation command of DL/UL configured grant. With smaller size payload, the number of needed CCEs to carry PDCCH may be reduced which enables gNB to schedule reduced capability NR devices through UE-specific PDCCH while using less CCEs. The new DCI formats may contain the fields described above which are essential for activation and deactivation of configured grant.
These new DCI formats may be scrambled with C-RNTI or CS-RNTI, but for rescheduling legacy PDCCH scrambled with CS-RNTI may be used.
Triggering Aperiodic CSI
A number of solutions are available to enable gNB to trigger aperiodic CSI reporting for a group of UEs instead of using UE-specific PDCCH for each individual UE. The framework is similar to the framework of scheduling/providing deactivation and/or activation command to a group of UEs described above.
The gNB may use GC-PDCCH to trigger aperiodic CSI report. A field similar to “CSI request” field may be included in the DCI payload of GC-PDCCH which may be labeled as “GC CSI request” field. The position of “GC CSI request” may be configured through higher layer signaling such as RRC parameter GC_CSI_request_positionInDCI to point to the start position within the DCI payload of GC-PDCCH.
DCI payload of GC-PDCCH may include one “GC CSI request” field that is applied for all UEs receiving GC-PDCCH. Also, the DCI payload of GC-PDCCH may include multiple “GC CSI request” field for each UE or sub-group of UEs receiving GC-PDCCH. The aforementioned solutions on how to indicate the position of “Grant Index,” “Activation Indicator,” “Deactivation Indicator,” “TDRA,” “FDRA,” etc. in DCI payload may be applied for “GC CSI request” field.
All the aforementioned solutions on how to GC-PDCCH above may be applied here as well, e.g., using dedicated RNTI, CORESET, search space set, etc. For example, GC-PDCCH that carries GC CSI request field may have a dedicated RNTI differ from the RNTI for GC-PDCCH used for providing dynamic grant or provide deactivation and/or activation command of configured grant.
Alternatively, GC PDCCH may field to indicate the purpose of GC-PDCCH and hence the UE knows how to interpret its fields. Table 14 of the Appendix shows an example of such field.
Since gNB needs to provide the UEs with UL grants to transmit CSI report, procedures similar to those described above may be applied. For example, the aforementioned solutions on how to provide non-colliding grants may be applied such that each UE can report CSI without colliding with any other UEs.
In case of the need of a retransmission of PUSCH carrying CSI report, UE expects to be scheduled with UE-specific PDCCH scrambled with C-RNTI.
Similarly, piggybacked DCI on anchor PDSCH may be used to trigger aperiodic CSI reports where additional field of CSI request is included in GC-PDCCH. All the aforementioned solutions related to where and when to monitor the piggybacked DCI and all other details may be applied here as well.
Moreover, a purpose field similar to Table 14 may be included in the piggybacked DCI to indicate the purpose of the piggybacked DCI.
Triggering Semi Persistent CSI Reporting on PUSCH
All of the aforementioned solutions may be applied for triggering semi-persistent CSI reporting. The key difference is that the GC-PDCCH or the piggybacked DCI may need to carry indication to its purpose or “purpose” indicator, for either activation or deactivation of semi-persistent CSI reporting. Therefore, solutions similar to all the solutions described herein for activating or deactivating DL/UL configured grant may be applied.
Example Environments
The 3rd Generation Partnership Project (3GPP) develops technical standards for cellular telecommunications network technologies, including radio access, the core transport network, and service capabilities—including work on codecs, security, and quality of service. Recent radio access technology (RAT) standards include WCDMA (commonly referred as 3G), LTE (commonly referred as 4G), LTE-Advanced standards, and New Radio (NR), which is also referred to as “5G.” 3GPP NR standards development is expected to continue and include the definition of next generation radio access technology (new RAT), which is expected to include the provision of new flexible radio access below 7 GHz, and the provision of new ultra-mobile broadband radio access above 7 GHz. The flexible radio access is expected to consist of a new, non-backwards compatible radio access in new spectrum below 7 GHz, and it is expected to include different operating modes that may be multiplexed together in the same spectrum to address a broad set of 3GPP NR use cases with diverging requirements. The ultra-mobile broadband is expected to include cmWave and mmWave spectrum that will provide the opportunity for ultra-mobile broadband access for, e.g., indoor applications and hotspots. In particular, the ultra-mobile broadband is expected to share a common design framework with the flexible radio access below 7 GHz, with cmWave and mmWave specific design optimizations.
3GPP has identified a variety of use cases that NR is expected to support, resulting in a wide variety of user experience requirements for data rate, latency, and mobility. The use cases include the following general categories: enhanced mobile broadband (eMBB) ultra-reliable low-latency Communication (URLLC), massive machine type communications (mMTC), network operation (e.g., network slicing, routing, migration and interworking, energy savings), and enhanced vehicle-to-everything (eV2X) communications, which may include any of Vehicle-to-Vehicle Communication (V2V), Vehicle-to-Infrastructure Communication (V21), Vehicle-to-Network Communication (V2N), Vehicle-to-Pedestrian Communication (V2P), and vehicle communications with other entities. Specific service and applications in these categories include, e.g., monitoring and sensor networks, device remote controlling, bi-directional remote controlling, personal cloud computing, video streaming, wireless cloud-based office, first responder connectivity, automotive ecall, disaster alerts, real-time gaming, multi-person video calls, autonomous driving, augmented reality, tactile internet, virtual reality, home automation, robotics, and aerial drones to name a few. All of these use cases and others are contemplated herein.
It will be appreciated that the concepts disclosed herein may be used with any number of WTRUs, base stations, networks, and/or network elements. Each of the WTRUs 102 may be any type of apparatus or device configured to operate and/or communicate in a wireless environment. In the example of
The communications system 100 may also include a base station 114a and a base station 114b. In the example of
TRPs 119a, 119b may be any type of device configured to wirelessly interface with at least one of the WTRU 102d, to facilitate access to one or more communication networks, such as the core network 106/107/109, the Internet 110, Network Services 113, and/or other networks 112. RSUs 120a and 120b may be any type of device configured to wirelessly interface with at least one of the WTRU 102e or 102f, to facilitate access to one or more communication networks, such as the core network 106/107/109, the Internet 110, other networks 112, and/or Network Services 113. By way of example, the base stations 114a, 114b may be a Base Transceiver Station (BTS), a Node-B, an eNode B, a Home Node B, a Home eNode B, a Next Generation Node-B (gNode B), a satellite, a site controller, an access point (AP), a wireless router, and the like.
The base station 114a may be part of the RAN 103/104/105, which may also include other base stations and/or network elements (not shown), such as a Base Station Controller (BSC), a Radio Network Controller (RNC), relay nodes, etc. Similarly, the base station 114b may be part of the RAN 103b/104b/105b, which may also include other base stations and/or network elements (not shown), such as a BSC, a RNC, relay nodes, etc. The base station 114a may be configured to transmit and/or receive wireless signals within a particular geographic region, which may be referred to as a cell (not shown). Similarly, the base station 114b may be configured to transmit and/or receive wired and/or wireless signals within a particular geographic region, which may be referred to as a cell (not shown). The cell may further be divided into cell sectors. For example, the cell associated with the base station 114a may be divided into three sectors. Thus, for example, the base station 114a may include three transceivers, e.g., one for each sector of the cell. The base station 114a may employ Multiple-Input Multiple Output (MIMO) technology and, therefore, may utilize multiple transceivers for each sector of the cell, for instance.
The base station 114a may communicate with one or more of the WTRUs 102a, 102b, 102c, and 102g over an air interface 115/116/117, which may be any suitable wireless communication link (e.g., Radio Frequency (RF), microwave, infrared (IR), ultraviolet (UV), visible light, cmWave, mmWave, etc.). The air interface 115/116/117 may be established using any suitable Radio Access Technology (RAT).
The base station 114b may communicate with one or more of the RRHs 118a and 118b, TRPs 119a and 119b, and/or RSUs 120a and 120b, over a wired or air interface 115b/116b/117b, which may be any suitable wired (e.g., cable, optical fiber, etc.) or wireless communication link (e.g., RF, microwave, IR, UV, visible light, cmWave, mmWave, etc.). The air interface 115b/116b/117b may be established using any suitable RAT.
The RRHs 118a, 118b, TRPs 119a, 119b and/or RSUs 120a, 120b, may communicate with one or more of the WTRUs 102c, 102d, 102e, 102f over an air interface 115c/116c/117c, which may be any suitable wireless communication link (e.g., RF, microwave, IR, ultraviolet UV, visible light, cmWave, mmWave, etc.) The air interface 115c/116c/117c may be established using any suitable RAT.
The WTRUs 102 may communicate with one another over a direct air interface 115d/116d/117d, such as Sidelink communication which may be any suitable wireless communication link (e.g., RF, microwave, IR, ultraviolet UV, visible light, cmWave, mmWave, etc.) The air interface 115d/116d/117d may be established using any suitable RAT.
The communications system 100 may be a multiple access system and may employ one or more channel access schemes, such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, and the like. For example, the base station 114a in the RAN 103/104/105 and the WTRUs 102a, 102b, 102c, or RRHs 118a, 118b, TRPs 119a, 119b and/or RSUs 120a and 120b in the RAN 103b/104b/105b and the WTRUs 102c, 102d, 102e, and 102f, may implement a radio technology such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), which may establish the air interface 115/116/117 and/or 115c/116c/117c respectively using Wideband CDMA (WCDMA). WCDMA may include communication protocols such as High-Speed Packet Access (HSPA) and/or Evolved HSPA (HSPA+). HSPA may include High-Speed Downlink Packet Access (HSDPA) and/or High-Speed Uplink Packet Access (HSUPA).
The base station 114a in the RAN 103/104/105 and the WTRUs 102a, 102b, 102c, and 102g, or RRHs 118a and 118b, TRPs 119a and 119b, and/or RSUs 120a and 120b in the RAN 103b/104b/105b and the WTRUs 102c, 102d, may implement a radio technology such as Evolved UMTS Terrestrial Radio Access (E-UTRA), which may establish the air interface 115/116/117 or 115c/116c/117c respectively using Long Term Evolution (LTE) and/or LTE-Advanced (LTE-A), for example. The air interface 115/116/117 or 115c/116c/117c may implement 3GPP NR technology. The LTE and LTE-A technology may include LTE D2D and/or V2X technologies and interfaces (such as Sidelink communications, etc.) Similarly, the 3GPP NR technology may include NR V2X technologies and interfaces (such as Sidelink communications, etc.)
The base station 114a in the RAN 103/104/105 and the WTRUs 102a, 102b, 102c, and 102g or RRHs 118a and 118b, TRPs 119a and 119b, and/or RSUs 120a and 120b in the RAN 103b/104b/105b and the WTRUs 102c, 102d, 102e, and 102f may implement radio technologies such as IEEE 802.16 (e.g., Worldwide Interoperability for Microwave Access (WiMAX)), CDMA2000, CDMA2000 1×, CDMA2000 EV-DO, Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Global System for Mobile communications (GSM), Enhanced Data rates for GSM Evolution (EDGE), GSM EDGE (GERAN), and the like.
The base station 114c in
The RAN 103/104/105 and/or RAN 103b/104b/105b may be in communication with the core network 106/107/109, which may be any type of network configured to provide voice, data, messaging, authorization and authentication, applications, and/or Voice Over Internet Protocol (VoIP) services to one or more of the WTRUs 102. For example, the core network 106/107/109 may provide call control, billing services, mobile location-based services, pre-paid calling, Internet connectivity, packet data network connectivity, Ethernet connectivity, video distribution, etc., and/or perform high-level security functions, such as user authentication.
Although not shown in
The core network 106/107/109 may also serve as a gateway for the WTRUs 102 to access the PSTN 108, the Internet 110, and/or other networks 112. The PSTN 108 may include circuit-switched telephone networks that provide Plain Old Telephone Service (POTS). The Internet 110 may include a global system of interconnected computer networks and devices that use common communication protocols, such as the Transmission Control Protocol (TCP), User Datagram Protocol (UDP), and the internet protocol (IP) in the TCP/IP internet protocol suite. The other networks 112 may include wired or wireless communications networks owned and/or operated by other service providers. For example, the networks 112 may include any type of packet data network (e.g., an IEEE 802.3 Ethernet network) or another core network connected to one or more RANs, which may employ the same RAT as the RAN 103/104/105 and/or RAN 103b/104b/105b or a different RAT.
Some or all of the WTRUs 102a, 102b, 102c, 102d, 102e, and 102f in the communications system 100 may include multi-mode capabilities, e.g., the WTRUs 102a, 102b, 102c, 102d, 102e, and 102f may include multiple transceivers for communicating with different wireless networks over different wireless links. For example, the WTRU 102g shown in
Although not shown in
As shown in
The core network 106 shown in
The RNC 142a in the RAN 103 may be connected to the MSC 146 in the core network 106 via an IuCS interface. The MSC 146 may be connected to the MGW 144. The MSC 146 and the MGW 144 may provide the WTRUs 102a, 102b, and 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, and 102c, and traditional land-line communications devices.
The RNC 142a in the RAN 103 may also be connected to the SGSN 148 in the core network 106 via an IuPS interface. The SGSN 148 may be connected to the GGSN 150. The SGSN 148 and the GGSN 150 may provide the WTRUs 102a, 102b, and 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between and the WTRUs 102a, 102b, and 102c, and IP-enabled devices.
The core network 106 may also be connected to the other networks 112, which may include other wired or wireless networks that are owned and/or operated by other service providers.
The RAN 104 may include eNode-Bs 160a, 160b, and 160c, though it will be appreciated that the RAN 104 may include any number of eNode-Bs. The eNode-Bs 160a, 160b, and 160c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, and 102c over the air interface 116. For example, the eNode-Bs 160a, 160b, and 160c may implement MIMO technology. Thus, the eNode-B 160a, for example, may use multiple antennas to transmit wireless signals to, and receive wireless signals from, the WTRU 102a.
Each of the eNode-Bs 160a, 160b, and 160c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in the uplink and/or downlink, and the like. As shown in
The core network 107 shown in
The MME 162 may be connected to each of the eNode-Bs 160a, 160b, and 160c in the RAN 104 via an S1 interface and may serve as a control node. For example, the MME 162 may be responsible for authenticating users of the WTRUs 102a, 102b, and 102c, bearer activation/deactivation, selecting a particular serving gateway during an initial attach of the WTRUs 102a, 102b, and 102c, and the like. The MME 162 may also provide a control plane function for switching between the RAN 104 and other RANs (not shown) that employ other radio technologies, such as GSM or WCDMA.
The serving gateway 164 may be connected to each of the eNode-Bs 160a, 160b, and 160c in the RAN 104 via the S1 interface. The serving gateway 164 may generally route and forward user data packets to/from the WTRUs 102a, 102b, and 102c. The serving gateway 164 may also perform other functions, such as anchoring user planes during inter-eNode B handovers, triggering paging when downlink data is available for the WTRUs 102a, 102b, and 102c, managing and storing contexts of the WTRUs 102a, 102b, and 102c, and the like.
The serving gateway 164 may also be connected to the PDN gateway 166, which may provide the WTRUs 102a, 102b, and 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c, and IP-enabled devices.
The core network 107 may facilitate communications with other networks. For example, the core network 107 may provide the WTRUs 102a, 102b, and 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, and 102c and traditional land-line communications devices. For example, the core network 107 may include, or may communicate with, an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that serves as an interface between the core network 107 and the PSTN 108. In addition, the core network 107 may provide the WTRUs 102a, 102b, and 102c with access to the networks 112, which may include other wired or wireless networks that are owned and/or operated by other service providers.
The RAN 105 may include gNode-Bs 180a and 180b. It will be appreciated that the RAN 105 may include any number of gNode-Bs. The gNode-Bs 180a and 180b may each include one or more transceivers for communicating with the WTRUs 102a and 102b over the air interface 117. When integrated access and backhaul connection are used, the same air interface may be used between the WTRUs and gNode-Bs, which may be the core network 109 via one or multiple gNBs. The gNode-Bs 180a and 180b may implement MIMO, MU-MIMO, and/or digital beamforming technology. Thus, the gNode-B 180a, for example, may use multiple antennas to transmit wireless signals to, and receive wireless signals from, the WTRU 102a. It should be appreciated that the RAN 105 may employ of other types of base stations such as an eNode-B. It will also be appreciated the RAN 105 may employ more than one type of base station. For example, the RAN may employ eNode-Bs and gNode-Bs.
The N3IWF 199 may include a non-3GPP Access Point 180c. It will be appreciated that the N3IWF 199 may include any number of non-3GPP Access Points. The non-3GPP Access Point 180c may include one or more transceivers for communicating with the WTRUs 102c over the air interface 198. The non-3GPP Access Point 180c may use the 802.11 protocol to communicate with the WTRU 102c over the air interface 198.
Each of the gNode-Bs 180a and 180b may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in the uplink and/or downlink, and the like. As shown in
The core network 109 shown in
In the example of
In the example of
The AMF 172 may be connected to the RAN 105 via an N2 interface and may serve as a control node. For example, the AMF 172 may be responsible for registration management, connection management, reachability management, access authentication, access authorization. The AMF may be responsible forwarding user plane tunnel configuration information to the RAN 105 via the N2 interface. The AMF 172 may receive the user plane tunnel configuration information from the SMF via an N11 interface. The AMF 172 may generally route and forward NAS packets to/from the WTRUs 102a, 102b, and 102c via an N1 interface. The N1 interface is not shown in
The SMF 174 may be connected to the AMF 172 via an N11 interface. Similarly, the SMF may be connected to the PCF 184 via an N7 interface, and to the UPFs 176a and 176b via an N4 interface. The SMF 174 may serve as a control node. For example, the SMF 174 may be responsible for Session Management, IP address allocation for the WTRUs 102a, 102b, and 102c, management and configuration of traffic steering rules in the UPF 176a and UPF 176b, and generation of downlink data notifications to the AMF 172.
The UPF 176a and UPF 176b may provide the WTRUs 102a, 102b, and 102c with access to a Packet Data Network (PDN), such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, and 102c and other devices. The UPF 176a and UPF 176b may also provide the WTRUs 102a, 102b, and 102c with access to other types of packet data networks. For example, Other Networks 112 may be Ethernet Networks or any type of network that exchanges packets of data. The UPF 176a and UPF 176b may receive traffic steering rules from the SMF 174 via the N4 interface. The UPF 176a and UPF 176b may provide access to a packet data network by connecting a packet data network with an N6 interface or by connecting to each other and to other UPFs via an N9 interface. In addition to providing access to packet data networks, the UPF 176 may be responsible packet routing and forwarding, policy rule enforcement, quality of service handling for user plane traffic, downlink packet buffering.
The AMF 172 may also be connected to the N3IWF 199, for example, via an N2 interface. The N3IWF facilitates a connection between the WTRU 102c and the 5G core network 170, for example, via radio interface technologies that are not defined by 3GPP. The AMF may interact with the N3IWF 199 in the same, or similar, manner that it interacts with the RAN 105.
The PCF 184 may be connected to the SMF 174 via an N7 interface, connected to the AMF 172 via an N15 interface, and to an Application Function (AF) 188 via an N5 interface. The N15 and N5 interfaces are not shown in
The UDR 178 may act as a repository for authentication credentials and subscription information. The UDR may connect to network functions, so that network function can add to, read from, and modify the data that is in the repository. For example, the UDR 178 may connect to the PCF 184 via an N36 interface. Similarly, the UDR 178 may connect to the NEF 196 via an N37 interface, and the UDR 178 may connect to the UDM 197 via an N35 interface.
The UDM 197 may serve as an interface between the UDR 178 and other network functions. The UDM 197 may authorize network functions to access of the UDR 178. For example, the UDM 197 may connect to the AMF 172 via an N8 interface, the UDM 197 may connect to the SMF 174 via an N10 interface. Similarly, the UDM 197 may connect to the AUSF 190 via an N13 interface. The UDR 178 and UDM 197 may be tightly integrated.
The AUSF 190 performs authentication related operations and connects to the UDM 178 via an N13 interface and to the AMF 172 via an N12 interface.
The NEF 196 exposes capabilities and services in the 5G core network 109 to Application Functions (AF) 188. Exposure may occur on the N33 API interface. The NEF may connect to an AF 188 via an N33 interface, and it may connect to other network functions in order to expose the capabilities and services of the 5G core network 109.
Application Functions 188 may interact with network functions in the 5G Core Network 109. Interaction between the Application Functions 188 and network functions may be via a direct interface or may occur via the NEF 196. The Application Functions 188 may be considered part of the 5G Core Network 109 or may be external to the 5G Core Network 109 and deployed by enterprises that have a business relationship with the mobile network operator.
Network Slicing is a mechanism that could be used by mobile network operators to support one or more ‘virtual’ core networks behind the operator's air interface. This involves ‘slicing’ the core network into one or more virtual networks to support different RANs or different service types running across a single RAN. Network slicing enables the operator to create networks customized to provide optimized solutions for different market scenarios which demands diverse requirements, e.g., in the areas of functionality, performance and isolation.
3GPP has designed the 5G core network to support Network Slicing. Network Slicing is a good tool that network operators can use to support the diverse set of 5G use cases (e.g., massive IoT, critical communications, V2X, and enhanced mobile broadband) which demand very diverse and sometimes extreme requirements. Without the use of network slicing techniques, it is likely that the network architecture would not be flexible and scalable enough to efficiently support a wider range of use cases need when each use case has its own specific set of performance, scalability, and availability requirements. Furthermore, introduction of new network services should be made more efficient.
Referring again to
The core network 109 may facilitate communications with other networks. For example, the core network 109 may include, or may communicate with, an IP gateway, such as an IP Multimedia Subsystem (IMS) server, which serves as an interface between the 5G core network 109 and a PSTN 108. For example, the core network 109 may include, or communicate with a short message service (SMS) service center that facilities communication via the short message service. For example, the 5G core network 109 may facilitate the exchange of non-IP data packets between the WTRUs 102a, 102b, and 102c and servers or applications functions 188. In addition, the core network 170 may provide the WTRUs 102a, 102b, and 102c with access to the networks 112, which may include other wired or wireless networks that are owned and/or operated by other service providers.
The core network entities described herein and illustrated in
WTRUs A, B, C, D, E, and F may communicate with each other over a Uu interface 129 via the gNB 121 if they are within the access network coverage 131. In the example of
WTRUs A, B, C, D, E, and F may communicate with RSU 123a or 123b via a Vehicle-to-Network (V2N) 133 or Sidelink interface 125b. WTRUs A, B, C, D, E, and F may communicate to a V2X Server 124 via a Vehicle-to-Infrastructure (V21) interface 127. WTRUs A, B, C, D, E, and F may communicate to another UE via a Vehicle-to-Person (V2P) interface 128.
The processor 118 may be a general-purpose processor, a special purpose processor, a conventional processor, a digital signal processor (DSP), a plurality of microprocessors, one or more microprocessors in association with a DSP core, a controller, a microcontroller, Application Specific Integrated Circuits (ASICs), Field Programmable Gate Array (FPGAs) circuits, any other type of integrated circuit (IC), a state machine, and the like. The processor 118 may perform signal coding, data processing, power control, input/output processing, and/or any other functionality that enables the WTRU 102 to operate in a wireless environment. The processor 118 may be coupled to the transceiver 120, which may be coupled to the transmit/receive element 122. While
The transmit/receive element 122 of a UE may be configured to transmit signals to, or receive signals from, a base station (e.g., the base station 114a of
In addition, although the transmit/receive element 122 is depicted in
The transceiver 120 may be configured to modulate the signals that are to be transmitted by the transmit/receive element 122 and to demodulate the signals that are received by the transmit/receive element 122. As noted above, the WTRU 102 may have multi-mode capabilities. Thus, the transceiver 120 may include multiple transceivers for enabling the WTRU 102 to communicate via multiple RATs, for example NR and IEEE 802.11 or NR and E-UTRA, or to communicate with the same RAT via multiple beams to different RRHs, TRPs, RSUs, or nodes.
The processor 118 of the WTRU 102 may be coupled to, and may receive user input data from, the speaker/microphone 124, the keypad 126, and/or the display/touchpad/indicators 128 (e.g., a liquid crystal display (LCD) display unit or organic light-emitting diode (OLED) display unit. The processor 118 may also output user data to the speaker/microphone 124, the keypad 126, and/or the display/touchpad/indicators 128. In addition, the processor 118 may access information from, and store data in, any type of suitable memory, such as the non-removable memory 130 and/or the removable memory 132. The non-removable memory 130 may include random-access memory (RAM), read-only memory (ROM), a hard disk, or any other type of memory storage device. The removable memory 132 may include a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, and the like. The processor 118 may access information from, and store data in, memory that is not physically located on the WTRU 102, such as on a server that is hosted in the cloud or in an edge computing platform or in a home computer (not shown).
The processor 118 may receive power from the power source 134 and may be configured to distribute and/or control the power to the other components in the WTRU 102. The power source 134 may be any suitable device for powering the WTRU 102. For example, the power source 134 may include one or more dry cell batteries, solar cells, fuel cells, and the like.
The processor 118 may also be coupled to the GPS chipset 136, which may be configured to provide location information (e.g., longitude and latitude) regarding the current location of the WTRU 102. In addition to, or in lieu of, the information from the GPS chipset 136, the WTRU 102 may receive location information over the air interface 115/116/117 from a base station (e.g., base stations 114a, 114b) and/or determine its location based on the timing of the signals being received from two or more nearby base stations. It will be appreciated that the WTRU 102 may acquire location information by way of any suitable location-determination method.
The processor 118 may further be coupled to other peripherals 138, which may include one or more software and/or hardware modules that provide additional features, functionality, and/or wired or wireless connectivity. For example, the peripherals 138 may include various sensors such as an accelerometer, biometrics (e.g., finger print) sensors, an e-compass, a satellite transceiver, a digital camera (for photographs or video), a universal serial bus (USB) port or other interconnect interfaces, a vibration device, a television transceiver, a hands free headset, a Bluetooth® module, a frequency modulated (FM) radio unit, a digital music player, a media player, a video game player module, an Internet browser, and the like.
The WTRU 102 may be included in other apparatuses or devices, such as a sensor, consumer electronics, a wearable device such as a smart watch or smart clothing, a medical or eHealth device, a robot, industrial equipment, a drone, a vehicle such as a car, truck, train, or an airplane. The WTRU 102 may connect to other components, modules, or systems of such apparatuses or devices via one or more interconnect interfaces, such as an interconnect interface that may comprise one of the peripherals 138.
In operation, processor 91 fetches, decodes, and executes instructions, and transfers information to and from other resources via the computing system's main data-transfer path, system bus 80. Such a system bus connects the components in computing system 90 and defines the medium for data exchange. System bus 80 typically includes data lines for sending data, address lines for sending addresses, and control lines for sending interrupts and for operating the system bus. An example of such a system bus 80 is the PCI (Peripheral Component Interconnect) bus.
Memories coupled to system bus 80 include random access memory (RAM) 82 and read only memory (ROM) 93. Such memories include circuitry that allows information to be stored and retrieved. ROMs 93 generally contain stored data that cannot easily be modified. Data stored in RAM 82 may be read or changed by processor 91 or other hardware devices. Access to RAM 82 and/or ROM 93 may be controlled by memory controller 92. Memory controller 92 may provide an address translation function that translates virtual addresses into physical addresses as instructions are executed. Memory controller 92 may also provide a memory protection function that isolates processes within the system and isolates system processes from user processes. Thus, a program running in a first mode may access only memory mapped by its own process virtual address space; it cannot access memory within another process's virtual address space unless memory sharing between the processes has been set up.
In addition, computing system 90 may contain peripherals controller 83 responsible for communicating instructions from processor 91 to peripherals, such as printer 94, keyboard 84, mouse 95, and disk drive 85.
Display 86, which is controlled by display controller 96, is used to display visual output generated by computing system 90. Such visual output may include text, graphics, animated graphics, and video. The visual output may be provided in the form of a graphical user interface (GUI). Display 86 may be implemented with a CRT-based video display, an LCD-based flat-panel display, gas plasma-based flat-panel display, or a touch-panel. Display controller 96 includes electronic components required to generate a video signal that is sent to display 86.
Further, computing system 90 may contain communication circuitry, such as for example a wireless or wired network adapter 97, that may be used to connect computing system 90 to an external communications network or devices, such as the RAN 103/104/105, Core Network 106/107/109, PSTN 108, Internet 110, WTRUs 102, or Other Networks 112 of
It is understood that any or all of the apparatuses, systems, methods, and processes described herein may be embodied in the form of computer executable instructions (e.g., program code) stored on a computer-readable storage medium which instructions, when executed by a processor, such as processors 118 or 91, cause the processor to perform and/or implement the systems, methods and processes described herein. Specifically, any of the steps, operations, or functions described herein may be implemented in the form of such computer executable instructions, executing on the processor of an apparatus or computing system configured for wireless and/or wired network communications. Computer readable storage media includes volatile and nonvolatile, removable, and non-removable media implemented in any non-transitory (e.g., tangible, or physical) method or technology for storage of information, but such computer readable storage media do not include signals. Computer readable storage media include, but are not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other tangible or physical medium which may be used to store the desired information, and which may be accessed by a computing system.
This application claims the benefit of U.S. Provisional Patent Application No. 63/116,275 filed on Nov. 20, 2020, titled “PDCCH enhancements for reduced capability new radio devices,” the content of which is hereby incorporated by reference herein.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2021/059908 | 11/18/2021 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 63116275 | Nov 2020 | US |
