Patent Description:
<NPL>, discusses CRS rate matching in Multi-DCI based Multi-TRP.

<NPL>,discusses multi-DCI based multi-TRP/panel transmission and default spatial relation and default pathloss RS of PUSCH.

A selection of optional features of the invention is set out in the dependent claims.

The exemplary embodiments may be further understood with reference to the following description and the related appended drawings, wherein like elements are provided with the same reference numerals. The exemplary embodiments describe various solutions for a UE in multi-DCI based multi-TRP operation.

The exemplary embodiments are described with regard to a UE. However, reference to a UE is merely provided for illustrative purposes. The exemplary embodiments may be utilized with any electronic component that may establish a connection to a network and is configured with the hardware, software, and/or firmware to exchange information and data with the network. Therefore, the UE as described herein is used to represent any electronic component.

In addition, the exemplary embodiments are described with regard to a <NUM> New Radio (NR) cellular network. However, reference to a <NUM> NR network is merely provided for illustrative purposes. The exemplary embodiments may be utilized with any network that implements the functionalities described herein for UE capability reporting. Therefore, the <NUM> NR network as described herein may represent any network that includes the functionalities described herein for the <NUM> NR network.

Multiple transmission and reception point (multi-TRP) functionality involves a UE maintaining multiple links with multiple TRPs (e.g. multiple gNBs) concurrently on the same carrier. As described above, when operating in multi-TRP, the UE may be in single-DCI or multi-DCI mode. The exemplary embodiments are related to a UE in multi-DCI based multi-TRP operation.

The multi-DCI mode may have various characteristics. For example, each TRP may be scheduled by a control resource set (CORESET) that has a corresponding CORESETPoolIndex from {<NUM>, <NUM>}, e.g., there are two pools of CORESETS. When the CORESETPoolIndex is not configured, it may be assumed to be <NUM>. A maximum of <NUM> CORESETs per bandwidth part (BWP) may be configured for each CORESETPoolIndex and a maximum of total <NUM> CORESETs per BWP may be configured. Two (<NUM>) Physical Downlink Shared Channels (PDSCH) may be fully/partial/non-overlapping. In addition, the Hybrid Automatic Repeat Request - Acknowledgement (HARQ-ACK) feedback supports both a separate and a joint feedback mode with a maximum of two (<NUM>) codeword (CW) and <NUM> HARQ processes.

Based on these characteristics of the multi-DCI operation, there are several issues that need to be addressed for effective multi-DCI operation. These include cell reference signal (CRS) rate matching patterns design, a default R for pdcch-BlindDetectionCA capability reporting (which will be described in greater detail below), a default HARQ-ACK feedback mode, a default Transmission Configuration Indication (TCI) state for Aperiodic Channel State Indication - Reference Signals (AP-CSI-RS), a default Physical Uplink Control Channel (PUCCH) default beam and pathloss RS and a conflict of multi-DCI and single-DCI configurations. The exemplary embodiments address each of these issues.

<FIG> shows an exemplary network arrangement <NUM> according to various exemplary embodiments. The exemplary network arrangement <NUM> includes a user equipment (UE) <NUM>. Those skilled in the art will understand that the UE may be any type of electronic component that is configured to communicate via a network, e.g., mobile phones, tablet computers, smartphones, phablets, embedded devices, wearable devices, Cat-M devices, Cat-M1 devices, MTC devices, eMTC devices, other types of Internet of Things (IoT) devices, etc. It should also be understood that an actual network arrangement may include any number of UEs being used by any number of users. Thus, the example of a single UE <NUM> is merely provided for illustrative purposes.

The UE <NUM> may communicate directly with one or more networks. In the example of the network configuration <NUM>, the networks with which the UE <NUM> may wirelessly communicate are a <NUM> NR radio access network (<NUM> NR-RAN) <NUM>, an LTE radio access network (LTE-RAN) <NUM> and a wireless local access network (WLAN) <NUM>. Therefore, the UE <NUM> may include a <NUM> NR chipset to communicate with the <NUM> NR-RAN <NUM>, an LTE chipset to communicate with the LTE-RAN <NUM> and an ISM chipset to communicate with the WLAN <NUM>. However, the UE <NUM> may also communicate with other types of networks (e.g. legacy cellular networks) and the UE <NUM> may also communicate with networks over a wired connection. With regard to the exemplary embodiments, the UE <NUM> may establish a connection with the <NUM> NR-RAN <NUM>.

The <NUM> NR-RAN <NUM> and the LTE-RAN <NUM> may be portions of cellular networks that may be deployed by cellular providers (e.g., Verizon, AT&T, Sprint, T-Mobile, etc.). These networks <NUM>, <NUM> may include, for example, cells or base stations (Node Bs, eNodeBs, HeNBs, eNBS, gNBs, gNodeBs, macrocells, microcells, small cells, femtocells, etc.) that are configured to send and receive traffic from UEs that are equipped with the appropriate cellular chip set. The WLAN <NUM> may include any type of wireless local area network (WiFi, Hot Spot, IEEE <NUM>. 11x networks, etc.).

The UE <NUM> may connect to the <NUM> NR-RAN via at least one of the next generation nodeB (gNB) 120A and/or the gNB 120B. The gNBs 120A, 120B may be configured with the necessary hardware (e.g., antenna array), software and/or firmware to perform massive multiple in multiple out (MIMO) functionality. Massive MIMO may refer to a base station that is configured to generate a plurality of beams for a plurality of UEs. Reference to two gNB 120A, 120B is merely for illustrative purposes. The exemplary embodiments may apply to any appropriate number of gNBs. Specifically, the UE <NUM> may simultaneously connect to and exchange data with a plurality of gNBs 120A, 120B in a multi-cell CA configuration or a multi-TRP configuration. The UE <NUM> may also connect to the LTE-RAN <NUM> via either or both of the eNBs 122A, 122B, or to any other type of RAN, as mentioned above. In the network arrangement <NUM>, the UE <NUM> is shown as having a simultaneous connection to the gNBs 120A and 120B. The connections to the gNBs 120A, 120B may be, for example, multi-TRP connections where both of the gNBs 120A, 120B provide services for the UE <NUM> on a same channel.

In addition to the networks <NUM>, <NUM> and <NUM> the network arrangement <NUM> also includes a cellular core network <NUM>, the Internet <NUM>, an IP Multimedia Subsystem (IMS) <NUM>, and a network services backbone <NUM>. The cellular core network <NUM> may be considered to be the interconnected set of components that manages the operation and traffic of the cellular network. The cellular core network <NUM> also manages the traffic that flows between the cellular network and the Internet <NUM>. The IMS <NUM> may be generally described as an architecture for delivering multimedia services to the UE <NUM> using the IP protocol. The IMS <NUM> may communicate with the cellular core network <NUM> and the Internet <NUM> to provide the multimedia services to the UE <NUM>. The network services backbone <NUM> is in communication either directly or indirectly with the Internet <NUM> and the cellular core network <NUM>. The network services backbone <NUM> may be generally described as a set of components (e.g., servers, network storage arrangements, etc.) that implement a suite of services that may be used to extend the functionalities of the UE <NUM> in communication with the various networks.

<FIG> shows an exemplary UE <NUM> according to various exemplary embodiments. The UE <NUM> will be described with regard to the network arrangement <NUM> of <FIG>. The UE <NUM> may represent any electronic device and may include a processor <NUM>, a memory arrangement <NUM>, a display device <NUM>, an input/output (I/O) device <NUM>, a transceiver <NUM>, and other components <NUM>. The other components <NUM> may include, for example, an audio input device, an audio output device, a battery that provides a limited power supply, a data acquisition device, ports to electrically connect the UE <NUM> to other electronic devices, sensors to detect conditions of the UE <NUM>, etc..

The processor <NUM> may be configured to execute a plurality of engines for the UE <NUM>. For example, the engines may include a multi-DCI, multi-TRP engine <NUM>. The multi-DCI, multi-TRP engine <NUM> may perform operations to address the issues identified above with a UE in multi-DCI based multi-TRP operation. The specific operations will be described in further detail below.

The above referenced engine being an application (e.g., a program) executed by the processor <NUM> is only exemplary. The functionality associated with the engines may also be represented as a separate incorporated component of the UE <NUM> or may be a modular component coupled to the UE <NUM>, e.g., an integrated circuit with or without firmware. For example, the integrated circuit may include input circuitry to receive signals and processing circuitry to process the signals and other information. The engines may also be embodied as one application or separate applications. In addition, in some UEs, the functionality described for the processor <NUM> is split among two or more processors such as a baseband processor and an applications processor. The exemplary embodiments may be implemented in any of these or other configurations of a UE.

The memory <NUM> may be a hardware component configured to store data related to operations performed by the UE <NUM>. The display device <NUM> may be a hardware component configured to show data to a user while the I/O device <NUM> may be a hardware component that enables the user to enter inputs. The display device <NUM> and the I/O device <NUM> may be separate components or integrated together such as a touchscreen. The transceiver <NUM> may be a hardware component configured to establish a connection with the <NUM>-NR RAN <NUM>, the LTE RAN <NUM> etc. Accordingly, the transceiver <NUM> may operate on a variety of different frequencies or channels (e.g., set of consecutive frequencies).

As described above, a first issue to be resolved for a UE in multi-DCI based multi-TRP operation includes CRS rate matching pattern design. CRS rate matching is for the NR Physical Downlink Shared Channel (PDSCH) to rate match the LTE CRS at a resource element (RE) level to allow for LTE and NR coexistence in the same channel. In the exemplary embodiments, up to (<NUM>) CRS patterns may be supported per cell. This may include up to (<NUM>) CRS patterns in the frequency domain in the same cell if it is considered that LTE supports up to a <NUM> carrier while NR supports up to a <NUM> carrier. This may also include up to two (<NUM>) CRS patterns per frequency range if it is considered that NR supports multi-TRP operation.

<FIG> show three examples of CRS rate matching patterns according to various exemplary embodiments. A design consideration for the CRS rate matching patterns, for an individual serving cell, may be that the cell indicates to which (CORESETPoolIndex) the TRP belongs.

<FIG> shows a first exemplary CRS rate matching pattern <NUM> according to various exemplary embodiments. In this example, each CRS pattern <NUM>-<NUM> may be configured. This may include the information for each pattern such as, including v-Shift of the LTE CRS, the number of the LTE CRS port, the LTE downlink carrier frequency, the LTE downlink carrier bandwidth, the LTE Multimedia Broadcast Single Frequency Network (MBSFN) subframe configuration and a CORSETPoolIndex.

<FIG> shows a second exemplary CRS rate matching pattern <NUM> according to various exemplary embodiments. In this example, two (<NUM>) sets <NUM>, <NUM> of CRS patterns may be configured. Each CRS pattern set may include a CORSETPoolIndex, e.g., CRS pattern set <NUM> may have the CORSETPoolIndex{<NUM>} and CRS pattern set <NUM> may have the CORSETPoolIndex{<NUM>}. Each CRS pattern set <NUM>, <NUM> may also include a list of CRS patterns, e.g., CRS patterns <NUM>-<NUM> for CRS pattern set <NUM> and CRS patterns <NUM>-<NUM> for CRS pattern set <NUM>. Each CRS pattern may include the information as was described above with respect to <FIG>. However, in this example, the CORSETPoolIndex may not be included because this information is known based on the CRS pattern set <NUM>, <NUM> to which the CRS pattern belongs.

<FIG> shows a third exemplary CRS rate matching pattern <NUM> according to various exemplary embodiments. In this example, a new CRS pattern list is configured which corresponds to the secondary TRP. As was described above, each cell may support (<NUM>) CRS patterns in the frequency domain. Thus, the primary cell (e.g. gNB 120A) may support the CRS pattern list <NUM> that includes the CRS patterns <NUM>-<NUM>. The new CRS pattern list <NUM> including CRS patterns <NUM>-<NUM> may be configured to correspond to the secondary TRP (e.g., gNB 120B).

There may be situations where multiple CRS rate matching patterns are configured per TRP. The CORESETPoolIndex may only take on the values of <NUM>, <NUM> or not configured. Moreover, as described above, each CORESETPoolIndex may have a maximum of three (<NUM>) CRS rate matching patterns configured. The CORESETPoolIndex can be either explicitly or implicitly configured. In the explicit situation, the explicit configuration will be used. In the implicit situation, e.g., the CORESETPoolIndex is not configured, the CORESETPoolIndex may be assumed to be <NUM>. There is an exception to this assumption. When there are already three (<NUM>) CRS rate matching patterns explicitly configured with CORESETPoolIndex = <NUM> (e.g., the maximum number of CRS rate matching patterns per CORESETPoolIndex, the CORESETPoolIndex may be assumed to be <NUM>.

As described above, a second issue to be resolved for a UE in multi-DCI based multi-TRP operation is a default R for pdcch-BlindDetectionCA capability reporting. This refers to a UE capability with respect to blind detection and non-overlapping Control Channel Elements (CCE) in carrier aggregation (CA) operation. A DCI that is to be transmitted on the Physical Downlink Control Channel (PDCCH) to the UE <NUM> may be mapped to particular control channel elements (CCEs). However, a subframe may include DCI that is not relevant to the UE <NUM> and the UE <NUM> may not be aware of where the DCI intended for the UE <NUM> is located within the subframe. Thus, the UE <NUM> may be configured to the find the DCI relevant to the UE <NUM> within the subframe by monitoring and blindly decoding a particular set of PDCCH candidates (e.g., a set of one or more consecutive CCEs on which PDDCH for the UE <NUM> may be mapped).

For PDCCH decoding, the actual number of blind decodes and non-overlapped CCEs is controlled by the network in a parameter labeled as a BDFactorR or y. The UE <NUM> may report its R factor together with another a parameter labeled pdcch-BlindDetectionCA that may be set to a value of {<NUM>,<NUM>}. When the UE <NUM> reports the pdcch-BlindDetectionCA, the UE <NUM> may be indicated the BDFactorR as either y =<NUM> or y =R.

However, when the UE <NUM> does not report the pdcch-BlindDetectionCA parameter or when the UE does not report R, a default value of R is to be used. The exemplary embodiments provide various manners of determining the default value for R. In a first example, the UE <NUM> is required to report its R value {<NUM>,<NUM>}. Thus, there is no situation where a default value is needed because the UE <NUM> will always report the R value. In a second exemplary embodiment, it may be considered that the default value is {<NUM>}. In a third exemplary embodiment, it may be considered that the default value is {<NUM>}.

As described above, a third issue to be resolved for a UE in multi-DCI based multi-TRP operation is a default HARQ-ACK feedback mode. For multi-DCI based multi-TRP operation, the UE can be configured to one of two different HARQ-ACK feedback modes. A first HARQ-ACK feedback mode may be termed, "joint feedback", where the HARQ-ACK from two (<NUM>) PDSCHs are fed back in the same HARQ-ACK codebook. A second HARQ-ACK feedback mode may be termed, "separate feedback", where the HARQ-ACK from two (<NUM>) PDSCHs are fed back in separate HARQ-ACK codebooks, carried by two (<NUM>) separate PUCCHs.

<FIG> shows an exemplary method <NUM> of selecting a default HARQ-ACK feedback mode when the UE <NUM> is in multi-DCI based multi-TRP operation according to various exemplary embodiments. In <NUM>, the UE <NUM> determines whether the UE <NUM> is in multi-DCI based multi-TRP operation. The multi-DCI based multi-TRP operation is characterized by at least one CORESET being configured without a CORESETPoolIndex or with one CORESETPoolIndex = <NUM> and at least another CORESET being configured with CORESETPoolIndex = <NUM>. If the UE <NUM> is not in multi-DCI based multi-TRP operation, the method <NUM> ends.

If the UE <NUM> is in multi-DCI based multi-TRP operation, the method <NUM> proceeds to <NUM> where the UE <NUM> determines if it supports the separate feedback HARQ-ACK mode. If the UE <NUM> supports the separate feedback HARQ-ACK mode, the method <NUM> proceeds to <NUM> where the default HARQ feedback mode may be set to "separate feedback. " If it is determined in <NUM> that the UE <NUM> does not support the separate feedback HARQ-ACK mode but the UE supports joint HARQ-ACK mode, the method proceeds to <NUM> where the default HARQ-ACK feedback mode may be set to "joint feedback. " Thus, at the end of method <NUM>, the default HARQ-ACK feedback mode is set for the UE <NUM>.

As described above, a fourth issue to be resolved for a UE in multi-DCI based multi-TRP operation is a default Transmission Configuration Indication (TCI) state for Aperiodic Channel State Indication - Reference Signals (AP-CSI-RS). <FIG> shows an exemplary method <NUM> of selecting a default TCI state for AP-CSI-RS when the UE <NUM> is in multi-DCI based multi-TRP operation according to various exemplary embodiments. In <NUM>, the UE <NUM> determines whether the UE <NUM> is in multi-DCI based multi-TRP operation. The operation <NUM> is the same as the operation <NUM> described above. If the UE <NUM> is not in multi-DCI based multi-TRP operation, the method <NUM> ends.

If the UE <NUM> is in multi-DCI based multi-TRP operation, the method <NUM> proceeds to <NUM> where the UE <NUM> determines if the CORESET in the latest monitored PDCCH slot has a configured CORESETPoolIndex. If the CORESET in the latest monitored PDCCH slot has a configured CORESETPoolIndex, the method <NUM> proceeds to <NUM> where the default TCI state for AP-CSI-RS may be set to the CORESET that has the lowest CORESET-ID in the same CORESET pool as the CORESET in the latest monitored PDCCH slot. In this case, the CORESETPoolIndex is the same as the CORESET from which UE <NUM> decodes the DCI that triggers the AP-CS-RS. If it is determined in <NUM> that the CORESET in the latest monitored PDCCH slot does not have a configured CORESETPoolIndex, the method proceeds to <NUM> where the default TCI state for AP-CSI-RS may be set to the CORESET that has the lowest CORESET-ID in the CORESETPoolIndex{<NUM>}. Thus, at the end of method <NUM>, the default TCI state for AP-CSI-RS is set for the UE <NUM>.

As described above, a fifth issue to be resolved for a UE in multi-DCI based multi-TRP operation is a default Physical Uplink Control Channel (PUCCH) beam and pathloss RS. <FIG> shows an exemplary method <NUM> of selecting a default PUCCH beam and pathloss RS according to the present invention. In <NUM>, the UE <NUM> determines whether the UE <NUM> is in multi-DCI based multi-TRP operation. The operation <NUM> is the same as the operation <NUM> described above. If the UE <NUM> is not in multi-DCI based multi-TRP operation, the method <NUM> ends.

If the UE <NUM> is in multi-DCI based multi-TRP operation, the method <NUM> proceeds to <NUM> where the UE <NUM> determines if the PUCCH has been scheduled by a DCI. If the PUCCH has not been scheduled by a DCI, the method proceeds to <NUM> where the default TCI state and pathloss RS for the PUCCH may be set based on a latest PDCCH reception by the UE <NUM> in the CORESET with the lowest ID on the active downlink (DL) bandwidth part (BWP) of the primary cell (PCell), e.g., gNB 120A.

If the PUCCH has not been scheduled by a DCI, the method proceeds to <NUM>, where the UE <NUM> determines whether the CORESET in which the DCI has been decoded has a configured CORESETPoolIndex. If the CORESET in which the DCI has been decoded has a configured CORESETPoolIndex, the method <NUM> proceeds to <NUM> where the default TCI state and pathloss (PL) RS for the PUCCH may be set to the CORESET that has the lowest CORESET-ID in the same CORESET pool as the CORESET in which the DCI has been decoded. In this case, the CORESETPoolIndex is the same as the CORESET from which UE <NUM> decodes the DCI that triggers the PUCCH. If it is determined in <NUM> that the CORESET in which the DCI has been decoded does not have a configured CORESETPoolIndex, the method proceeds to <NUM> where the default TCI state and pathloss RS for the PUCCH may be set to the CORESET that has the lowest CORESET-ID in the CORESETPoolIndex{<NUM>}. Thus, at the end of method <NUM>, the default TCI state and pathloss RS for the PUCCH is set for the UE <NUM>.

As described above, a sixth issue to be resolved for a UE in multi-DCI based multi-TRP operation is to resolve a conflict between multi-DCI and single-DCI configurations. The UE <NUM> may be simultaneously configured for both multi-DCI based multi-TRP operation and single-DCI based multi-TRP operation. As described above, the UE <NUM> may be configured in multi-DCI based multi-TRP operation when at least one CORESET is configured without a CORESETPoolIndex or with a CORESETPoolIndex = <NUM> and at least another CORESET is configured with CORESETPoolIndex = <NUM>. The UE <NUM> may be configured in single-DCI based multi-TRP operation when a Medium Access Control - Control Element (MAC-CE) activates at least one TCI codepoint with <NUM> TCI States and/or Radio Resource Control (RRC) signaling configures a RepNumR16 parameter in at least in one entry in PDSCH-TimeDomainResourceAllocation. The RepNumR16 parameter indicates to the UE <NUM> that it may be receiving multiple TCI states corresponding to multi-TRP operation. Thus, if the UE <NUM> is configured with both multi-DCI and single-DCI based multi-TRP configurations, the UE <NUM> may need to resolve the conflict.

There may be several manners of resolving the conflict. In a first exemplary embodiment, the UE <NUM> may consider that the simultaneous multi-DCI and single-DCI based multi-TRP configuration is an error case. In this exemplary embodiment, the behavior of the UE <NUM> may be unspecified. In a second exemplary embodiment, when the UE <NUM> is configured with simultaneous multi-DCI and single-DCI based multi-TRP, the UE <NUM> may not monitor DCI scheduling from CORESETs in CORESETPoolIndex = <NUM>, e.g., the UE <NUM> will only monitor DCI scheduling for the primary cell.

In a third exemplary embodiment, when the UE <NUM> is configured with simultaneous multi-DCI and single-DCI based multi-TRP, the UE <NUM> may ignore the single-DCI based multi-TRP configuration and only operate in multi-DCI based multi-TRP operation. In a fourth exemplary embodiment, when the UE <NUM> is configured with simultaneous multi-DCI and single-DCI based multi-TRP, the UE <NUM> may ignore the multi-DCI based multi-TRP configuration and only operate in single-DCI based multi-TRP operation.

Thus, the above exemplary embodiments provide various solutions to resolve issues related to a UE in multi-DCI based multi-TRP operation.

Those skilled in the art will understand that the above-described exemplary embodiments may be implemented in any suitable software or hardware configuration or combination thereof. An exemplary hardware platform for implementing the exemplary embodiments may include, for example, an Intel x86 based platform with compatible operating system, a Windows OS, a Mac platform and MAC OS, a mobile device having an operating system such as iOS, Android, etc. In a further example, the exemplary embodiments of the above described method may be embodied as a program containing lines of code stored on a non-transitory computer readable storage medium that, when compiled, may be executed on a processor or microprocessor.

Claim 1:
A method, comprising:
at a user equipment, UE, in multiple Downlink Control Information, multi-DCI, based multiple transmission and reception point, multi-TRP, configuration having simultaneous connections with a first next generation node B, gNB, and a second gNB over a same carrier:
receiving, from one of the first or second gNBs, one or more cell reference signal, CRS, rate matching patterns, wherein the one or more CRS rate matching patterns comprise an indication of a control resource set, CORESET, pool for each of the one or more CRS rate matching patterns; and
applying the one or more CRS rate matching patterns to a CORESET for a Physical Downlink Shared Channel, PDSCH, based on the indication of the CORESET pool; characterised by
determining whether a Physical Uplink Control Channel, PUCCH, is scheduled by a DCI (<NUM>);
when the PUCCH is scheduled by the DCI, determining whether a CORESET from which the DCI is decoded has a configured CORESET pool (<NUM>);
when the CORESET from which the DCI is decoded has a configured CORESET pool, setting the default TCI state and pathloss reference signal to a CORESET having a lowest CORESET identification among CORESETs having the same CORESET pool indication as the DCI that triggers the PUCCH transmission in a latest PDCCH monitoring slot (<NUM>); and
when the CORESET from which the DCI is decoded does not have a configured CORESET pool, setting the default TCI state and pathloss reference signal to a CORESET in a predefined CORESET pool having a lowest CORSET identification (<NUM>).