WO2023187723A1

WO2023187723A1 - Method and apparatus for network energy efficient small data transmission from inactive user equipment

Info

Publication number: WO2023187723A1
Application number: PCT/IB2023/053213
Authority: WO
Inventors: Hyejung Jung; Joachim Löhr; Alexander Golitschek Edler Von Elbwart
Original assignee: Lenovo (Singapore) Pte. Ltd.
Priority date: 2022-04-01
Filing date: 2023-03-30
Publication date: 2023-10-05

Abstract

A method and apparatus are provided, in which a first indication of time domain positions of a first set of synchronization signal and physical broadcast channel blocks (SSBs) in a first SSB burst is received (202), wherein the first indication configures a transmission of a SSB with a first index. A second indication of time domain positions of a second set of SSBs in a second SSB burst is received (204), wherein the second indication indentifies the unavailability of the transmission of the SSB with the first index during a period of unavailability associated with a corresponding indication validity interval. A small data transmission (SDT) is transmitted (206) during the period of unavailability using a SDT resource of a plurality of configured SDT resources, wherein the SDT resource is not a part of a set of SDT resources associated with the SSB with the first index.

Description

METHOD AND APPARATUS FOR NETWORK ENERGY EFFICIENT

SMALL DATA TRANSMISSION FROM INACTIVE USER EQUIPMENT

FIELD OF THE INVENTION

The present disclosure is directed to the support of small data transmissions between the network and one or more user equipment in an inactive state, and more particularly a more dynamic approach in managing resources assigned to the support of the small data transmissions.

BACKGROUND OF THE INVENTION

Presently, user equipment, such as wireless communication devices, communicate with other communication devices using wireless signals, such as within a network environment that can include one or more cells within which various communication connections with the network and other devices operating within the network can be supported. Network environments often involve one or more sets of standards, which each define various aspects of any communication connection being made when using the corresponding standard within the network environment. Examples of developing and/or existing standards include new radio access technology (NR), Long Term Evolution (LTE), Universal Mobile Telecommunications Service (UMTS), Global System for Mobile Communication (GSM), and/or Enhanced Data GSM Environment (EDGE).

Traditionally, when a user equipment wants to communicate via the network, the user equipment establishes a connection. This can sometimes include the user equipment transitioning from a state identified as being 'inactive' to a state identified as being 'active', involving the associated overhead associated with supporting such a change of state, as well as can also include a reservation of communication resources in support of and for the duration of any such communication connection that is established. However, when the desired communication involves a small amount of data, the overhead associated with establishing a communication connection can be significant relative to the amount of data being transmitted. Some applications or use cases can involve an ongoing and/or periodic requirement for support of the communication of small amounts of data, which can result in the frequent establishment and tearing down of a communication connection, or a communication connection that is being maintained that is supporting intermittent use. Not only does the frequent establishment and tearing down of a communication connection involve a disproportionately larger amount of overhead signaling, but can also contribute to an overall increase in latency.

In order to better support the applications involving frequent and/or periodic requirements for the support of communications involving relatively small amounts of data, small data transmission protocols have been established, which can support small data transmissions from one or more user equipment, while the user equipment remains in an inactive state. However, this has resulted in the use of resources that are semi-statically configured for the duration of the configured grant, during which the network is generally expected to continuously monitor for small data transmissions. This can be relatively resource intensive for the network, even in instances where there is a low overall usage by the one or more user equipment of the corresponding configured grant.

The present inventors have recognized that it would be beneficial if the reservation of resources in support of small data transmissions could be more adaptively configured including the dynamic adjustment of various subsets of the allocated resources during all or some of the duration of the original configured grant.

SUMMARY

The present application provides a method in a user equipment. The method includes receiving a first indication of time domain positions of a first set of synchronization signal and physical broadcast channel blocks in a first synchronization signal and physical broadcast channel block burst, via a higher signaling layer, wherein the first indication configures a transmission of a synchronization signal and physical broadcast channel block with a first index. A second indication of time domain positions of a second set of synchronization signal and physical broadcast channel blocks is received in a second synchronization signal and physical broadcast channel block burst, wherein the second indication indentifies the unavailability of the transmission of the synchronization signal and physical broadcast channel block with the first index during a period of unavailability associated with a corresponding indication validity interval. A small data transmission is transmitted during the period of unavailability associated with the indication validity interval using a small data transmission resource of a plurality of configured small data transmission resources, wherein the small data transmission resource is not a part of a set of small data transmission resources associated with the synchronization signal and physical broadcast channel block with the first index.

According to another possible embodiment, a user equipment for communicating within a network is provided. The user equipment includes a controller. The user equipment further includes a transceiver for receiving a first indication of time domain positions of a first set of synchronization signal and physical broadcast channel blocks in a first synchronization signal and physical broadcast channel block burst, via a higher signaling layer, wherein in response to receiving the first indication, the controller configures a transmission of a synchronization signal and physical broadcast channel block with a first index. The transceiver further receives a second indication of time domain positions of a second set of synchronization signal and physical broadcast channel blocks in a second synchronization signal and physical broadcast channel block burst, wherein from the second indication the controller indentifies the unavailability of the transmission of the synchronization signal and physical broadcast channel block with the first index during a period of unavailability associated with a corresponding indication validity interval. The transceiver transmits a small data transmission during the period of unavailability associated with the indication validity interval using a small data transmission resource of a plurality of configured small data transmission resources, wherein the small data transmission resource is identified by the controller as not being a part of a set of small data transmission resources associated with the synchronization signal and physical broadcast channel block with the first index.

According to a further possible embodiment, a method in a network entity is provided. The method includes transmitting a first indication of time domain positions of a first set of synchronization signal and physical broadcast channel blocks in a first synchronization signal and physical broadcast channel block burst, via a higher signaling layer, wherein the first indication configures a transmission of a synchronization signal and physical broadcast channel block with a first index. A second indication of time domain positions of a second set of synchronization signal and physical broadcast channel blocks is transmitted in a second synchronization signal and physical broadcast channel block burst, wherein the second indication indentifies to one or more user equipment, the unavailability of the transmission of the synchronization signal and physical broadcast channel block with the first index during a period of unavailability associated with a corresponding indication validity interval. The monitoring is discontinued for a small data transmission from the one or more user equipment during the period of unavailability associated with the indication validity interval, of a set of small data transmission resources associated with the synchronization signal and physical broadcast channel block with the first index.

According to a still further possible embodiment, a network entity is provided. The network entity includes a controller. The network entity further includes a transceiver for transmitting a first indication of time domain positions of a first set of synchronization signal and physical broadcast channel blocks in a first synchronization signal and physical broadcast channel block burst, via a higher signaling layer, wherein the controller uses the first indication to configure a transmission of a synchronization signal and physical broadcast channel block with a first index. The transceiver further transmits a second indication of time domain positions of a second set of synchronization signal and physical broadcast channel blocks in a second synchronization signal and physical broadcast channel block burst, wherein the second indication is used by a controller of one or more user equipment to indentify the unavailability of the transmission of the synchronization signal and physical broadcast channel block with the first index during a period of unavailability associated with a corresponding indication validity interval. The transceiver discontinues the monitoring for a small data transmission from the one or more user equipment during the period of unavailability associated with the indication validity interval, of a set of small data transmission resources associated with the synchronization signal and physical broadcast channel block with the first index.

These and other features, and advantages of the present application are evident from the following description of one or more preferred embodiments, with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of an exemplary network environment in which the present invention is adapted to operate;

FIG. 2 is a flow diagram in a user equipment for dynamically managing resources assigned to the support of small data transmissions;

FIG. 3 is a flow diagram in a network entity for dynamically managing resources assigned to the support of small data transmissions; and

FIG. 4 is an example block diagram of an apparatus according to a possible embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

While the present disclosure is susceptible of embodiment in various forms, there is shown in the drawings and will hereinafter be described presently preferred embodiments with the understanding that the present disclosure is to be considered an exemplification of the invention and is not intended to limit the invention to the specific embodiments illustrated.

Embodiments provide for the dynamic management of resources assigned to the support of small data transmissions.

FIG. 1 is an example block diagram of a system 100 according to a possible embodiment. The system 100 can include a wireless communication device 110, such as User Equipment (UE), a base station 120, such as an enhanced NodeB (eNB) or next generation NodeB (gNB), and a network 130. The wireless communication device 110 can be a wireless terminal, a portable wireless communication device, a smartphone, a cellular telephone, a flip phone, a personal digital assistant, a personal computer, a selective call receiver, a tablet computer, a laptop computer, or any other device that is capable of sending and receiving communication signals on a wireless network.

The network 130 can include any type of network that is capable of sending and receiving wireless communication signals. For example, the network 130 can include a wireless communication network, a cellular telephone network, a Time Division Multiple Access (TDMA)-based network, a Code Division Multiple Access (CDMA)-based network, an Orthogonal Frequency Division Multiple Access (OFDMA)-based network, a Long Term Evolution (LTE) network, a 5th generation (5G) network, a 3rd Generation Partnership Project (3GPP)-based network, a satellite communications network, a high altitude platform network, the Internet, and/or other communications networks.

In 3 GPP New Radio (NR), a network may configure UEs performing infrequent (periodic and/or non-periodic) data transmissions while in an RRC INACTIVE state. When a UE is in an RRC INACTIVE state, the UE is expected to store inactive Access Stratum (AS) context, perform Public Land Mobile Network (PLMN) selection, receive broadcast system information, perform cell reselection mobility, and monitor paging. As for a network, a Next Generation Radio Access Network (NG-RAN) stores AS context of a UE and establishes connections between 5G Core (5GC) and NG-RAN for the UE in an RRC_INACTIVE state. Further, NG-RAN manages RAN-based notification areas (RNAs) with up-to-date knowledge of an RNA that the UE belongs to and initiates RAN paging when necessary.

In Rel-17 NR, a UE in an RRC INACTIVE state can transmit small amounts of data based on a 2-step or 4-step random access procedure and/or based on configured grant (CG) type-1 physical uplink shared channel (PUSCH) transmission without resuming an RRC connection (i.e. without transitioning to an RRC CONNECTED state), which can reduce the signaling overhead related to RRC connection setup and subsequent release procedures and may extend UE battery life. Some examples of small and infrequent data traffic include traffic from Instant Messaging services (IM), keep-alive traffic from IM or email clients and other apps, traffic from wearables (e.g. periodic positioning information), and sensors, such as industrial wireless sensor networks transmitting temperature and/or pressure readings, periodically or in an event triggered manner.

One potential drawback of small data transmissions from UEs in RRC INACTIVE state is that a network should reserve time and frequency resources for random access channel (RACH) occasions and/or PUSCH occasions and continuously attempt to detect physical random access channel (PRACH) preambles and/or PUSCH demodulation reference signal (DM RS) sequences on configured RACH occasions and/or PUSCH occasions, which may increase network energy consumption.

This current application presents methods to enable small data transmission from an RRC INACTIVE UE in a more network energy efficient manner.

Small Data Transmission (SDT) in Rel-17 NR is a procedure allowing a UE to perform data and/or signaling transmission while remaining in RRC INACTIVE (i.e. without transitioning to a RRC CONNECTED state). SDT is enabled on a radio bearer basis and is initiated by the UE only if an amount of pending uplink (UL) data is less than a configured value for all radio bearers for which SDT is enabled, a downlink (DL) reference signal received power (RSRP) is above a configured threshold value, and a valid SDT resource is available.

A UE can initiate an SDT procedure with either a transmission over a random access channel or over a Type 1 CG resource of a cell, which is configured via dedicated signaling, such as an RRCRelease message, received in the cell. The CG resources are considered to be valid, when an SDT-specific timing alignment timer (TAT) is running and DL RSRP of configured number of highest ranked synchronization signal (SS) and physical broadcast channel (PBCH) blocks (SSBs) which are above a configured RSRP threshold value. Upon expiry of the SDT- specific timing alignment timer, the Typel CG resources are released.

With successful completion of the SDT procedure, the UE is directed to RRC IDLE or RRC INACTIVE (via RRCRelease) or to RRC CONNECTED (via RRCResume). With cell re-selection, expiry of an SDT failure detection timer, or a radio link control (RLC) entity reaching a configured maximum retransmission threshold, the SDT procedure is unsuccessfully completed and accordingly, the UE transitions to RRC IDLE.

After a UE initiates SDT, a network can schedule subsequent UL (or DL) transmissions using dynamic UL grants (or dynamic DL assignments), or the UE can perform subsequent UL transmissions on following CG resource occasions, after reception of confirmation for the initial PUSCH transmission. If the SDT was initiated on RACH resources, subsequent UL and DL transmissions can be scheduled by the network after the completion of the random access procedure.

In the following, details of physical layer configuration of SDT specified in Rel-17 3rd Generation Partnership Project (3GPP) New Radio (NR) were provided.

From 3GPP Technical Specification (TS) 38.213 (V17)

19 PUSCH TRANSMISSION IN RRC_INACTICE STATE

19.1 CONFIGURED-GRANT BASED PUSCH TRANSMISSION

A UE indicated to release a dedicated RRC connection can be provided one or more configurations by respective one or more ConfiguredGrantConfig, for configured grant Type 1 PUSCH transmissions on the initial UL BWP [TS 38.331], For the remaining of this clause, PUSCH transmissions refer to configured grant Type-1 PUSCH transmissions for a configuration provided by ConfiguredGrantConfig.

A UE can be provided by sdt-SSB-Subset a number of SS/PBCH block indexes C ^{t0 ma}P ^{t0 a} number of valid PUSCH occasions for PUSCH transmissions over an association period. If the UE is not provided sdt-SSB-Subset, the UE determines NpuscH™ f^rom the value of ssb-PositionsInBurst in system information block #1 (SIB J) or by ServingCellConfigCommon. A PUSCH occasion for a PUSCH transmission is defined by a time resource and a frequency resource and is associated with a DM-RS provided by cg-DMRS-Configuration for the configuration of PUSCH transmissions. An association period, starting from frame SFN 0, for mapping Np^_s^^CH SS/PBCH block indexes, from the number of SS/PBCH block indexes, to valid PUSCH occasions and associated DM-RS resources is the smallest value in the set determined by the PUSCH configuration period such that iVpu^^CH SS/PBCH block indexes are mapped at least once to valid PUSCH occasions and associated DM-RS resources within the association period. A UE is provided a number of SS/PBCH block indexes associated with a PUSCH occasion and a DM-RS resource by sdt-SSB- perCG-PUSCH. If after an integer number of SS/PBCH block indexes to PUSCH occasions mapping cycles within the association period there is a set of PUSCH occasions that are not mapped to NpuscH™ SS/PBCH block indexes, no SS/PBCH block indexes are mapped to the set of PUSCH occasions. An association pattern period includes one or more association periods and is determined so that a pattern between PUSCH occasions and SS/PBCH block indexes repeats at most every 640 msec. PUSCH occasions not associated with SS/PBCH block indexes after an integer number of association periods, if any, are not used for PUSCH transmissions.

Each consecutive number of /V_pu ^/ _SCH SS/PBCH block indexes are mapped to valid PUSCH occasions and associated DMRS resources

- first, in increasing order of DMRS resource indexes within a PUSCH occasion, where a DMRS resource index DMRS_id is determined first in an ascending order of a DMRS port index and second in an ascending order of a DMRS sequence index [TS 38.211]

- second, in increasing order of PUSCH configuration period indexes.

A PUSCH occasion is valid if it does not overlap with a PRACH.

For unpaired spectrum and for SS/PBCH blocks with indexes provided by ssb- PositionsInBurst in SIB1 or by ServingCellConfigCommon

- if a UE is not provided tdd-UL-DL-ConfigurationCommon, a PUSCH occasion is valid if the PUSCH occasion

- does not precede a SS/PBCH block in the PUSCH slot, and

- starts at least A_gap symbols after a last SS/PBCH block symbol, where A_gap is provided in Table 8.1-2 of 3 GPP TS 38.213 - if a UE is provided tdd-UL-DL-ConfigurationCommon, a PUSCH occasion is valid if the PUSCH occasion

- is within UL symbols

- starts at least /V_gap symbols after a last downlink symbol, and at least /V_gap symbols after a last SS/PBCH block symbol, where A_gap is provided in Table 8.1-2 of 3GPP TS 38.213.

A UE determines a power of a PUSCH transmission as described in clause 7.1.1 of 3GPP TS 38.213, where the UE obtains PL^pc qa) using a RS resource from an SS/PBCH block with index associated with the PUSCH transmission.

A UE can be provided a USS set by sdt-CG-SearchSpace, or a common search space (CSS) set by sdl-SearchSpacg to monitor PDCCH for detection of downlink control information (DCI) format 0 0 with cyclic redundancy check (CRC) scrambled by cell -random network temporary identifier (C-RNTI) or configured scheduling (CS)-RNTI for scheduling PUSCH transmission or of DCI format 1 0 with CRC scrambled by C-RNTI for scheduling PDSCH receptions [TS 38.331], The UE may assume that the DM-RS antenna port associated with the PDCCH receptions, the DM- RS antenna port associated with the PDSCH receptions, and the SS/PBCH block associated with the PUSCH transmission are quasi co-located with respect to average gain and quasi co-location 'typeA' or 'typeD' properties. The UE transmits a PUCCH with hybrid automatic repeat request-acknowledgment (HARQ-ACK) information associated with the PDSCH receptions as described in clause 9.2.1 of 3GPP TS 38.213.

19.2 RANDOM-ACCESS BASED PUSCH TRANSMISSION

A UE indicated to release a dedicated radio resource control (RRC) connection can be provided a configuration for a Type-1 and/or a Type-2 random access procedure on the initial UL bandwidth part (BWP) [TS 38.331], PRACH occasions can have either a common configuration as, or a separate configuration from, PRACH occasions for Type-1 or Type-2 random access procedure as described in clause 8.1 of 3GPP TS 38.213. The UE procedure is as described in clause 8, including clauses 8.1 through 8.4 of 3GPP TS 38.213. The UE transmits a PRACH preamble with a power determined as described in clause 7.4 of 3GPP TS 38.213. For a common configuration of PRACH occasions and a Type-1 or a Type-2 random access procedure, a UE can be provided a number of SS/PBCH block indexes associated with one PRACH occasion by sdt-CB-PreamblesPerSSB-PerSharedRO or sdt-msgA-CB-PreamblesPerSSB-PerSharedRO, respectively. A PRACH transmission can be on a subset of PRACH occasions associated with a same SS/PBCH block index within an SSB-RO mapping cycle as determined by a PRACH mask index provided by sdt-SSB-SharedRO-Masklndex or sdt-msgA-SSB-SharedRO-Masklndex according to [TS 38.321],

A UE can be provided by sdt-SearchSpace a CSS set to monitor, after contention resolution as described in clause 8.4, PDCCH for detection of a DCI format 0 0 or DCI format 1 0 with CRC scrambled by C-RNTI for scheduling respective PUSCH transmissions or PDSCH receptions; otherwise, if the UE is not provided sdt-SearchSpace, the UE monitors PDCCH according to a Type 1 -PDCCH CSS set as described in clause 10.1 of 3GPP TS 38.213. The UE may assume that the DM-RS antenna port associated with the PDCCH receptions, the DM-RS antenna port associated with the PDSCH receptions, and the SS/PBCH block associated with the PRACH transmission are quasi co-located with respect to average gain and quasi colocation 'typeA' or 'typeD' properties.

From 3GPP TS 38.214 (V17)

6.2.2 UE DM-RS transmission procedure

When transmitted PUSCH is scheduled by activation DCI format 0 0 with CRC scrambled by CS-RNTI, the UE shall use single symbol front-loaded DM-RS of configuration type provided by higher layer parameter dmrs-Type in DMRS- UplinkConfig on DM-RS port 0 and the remaining REs not used for DM-RS in the symbols are not used for any PUSCH transmission except for PUSCH with allocation duration of 2 or less OFDM symbols with transform precoding disabled, and additional DM-RS with dmrs-AdditionalPosition from ConfiguredGrantConfig can be transmitted according to the scheduling type and the PUSCH duration as specified in Table 6.4.1.1.3-3 of [TS38.211] for frequency hopping disabled and as specified in Table 6.4.1.1.3-6 of [TS38.211] for frequency hopping enabled. For the UE-specific reference signals generation as defined in Clause 6.4.1.1 of [TS 38.211], a UE can be configured by higher layers with one or two scrambling identity(s), n ^RS'¹ / = 0,1 which are the same for both PUSCH mapping Type A and Type B.

When transmitted PUSCH is scheduled by DCI format 0 1 with CRC scrambled by C-RNTI, CS-RNTI, semi-peristent (SP)-channel state information (CSI)-RNTI or modulation and coding scheme (MCS)-C-RNTI, or corresponding to a configured grant, or being a PUSCH for Type-2 random access procedure,

- for PUSCH corresponding to a configured grant in absence of RRC connection, the UE is provided with DM-RS port(s) by [DMRS-UplinkConfigs\, and the DM-RS resource index DMRS_id is determined as defined in Clause 19.1 of [TS 38.213],

- the UE may be configured with higher layer parameter dmrs-Type in DMRS- UplinkConfig, and the configured DM-RS configuration type is used for transmitting PUSCH in as defined in Clause 6.4.1.1 of [TS 38.211],

- the UE may be configured with the maximum number of front-loaded DM-RS symbols for PUSCH by higher layer parameter maxLength in DMRS- UplinkConfig, or by higher layer parameter msgA-MaxLength in msgA-DMRS- Config,

- if maxLength is not configured, single-symbol DM-RS can be scheduled for the UE by DCI or configured by the configured grant configuration, and the UE can be configured with a number of additional DM-RS for PUSCH by higher layer parameter dmrs-AdditionalPosition, which can be 'posO', 'posl', 'pos2', 'pos3'.

- if maxLength is configured, either single-symbol DM-RS or double symbol DM-RS can be scheduled for the UE by DCI or configured by the configured grant configuration, and the UE can be configured with a number of additional DM-RS for PUSCH by higher layer parameter dmrs- AdditionalPosition, which can be 'posO' or 'posl'.

- for msgA PUSCH for Type-2 random access procedure the UE can be configured with a number of additional DM-RS for PUSCH by higher layer parameter msgA-DMRS-AdditionalPosition, which can be 'posO', 'post', 'pos2', 'pos3' for single-symbol DM-RS or 'posO', 'post' for double-symbol DM-RS.

- and, the UE shall transmit a number of additional DM-RS as specified in Table 6.4.1.1.3-3 and Table 6.4.1.1.3-4 in -Clause 6.4.1.1.3 of [TS 38.211],

If a UE transmitting PUSCH scheduled by DCI format 0 2 is configured with the higher layer parameter phaseTrackingRS in dmrs-UplinkForPUSCH- MappingTypeA-DCI-0-2 or dmrs-UplinkForPUSCH-MappingTypeB-DCI-0-2, or a UE transmitting PUSCH scheduled by DCI format 0 0 or DCI format 0 1 is configured with the higher layer parameter phaseTrackingRS in dmrs- UplinkForPUSCH-MappingTypeA or dmrs-UplinkForPUSCH-MappingTypeB, the UE may assume that the following configurations are not occurring simultaneously for the transmitted PUSCH

- any DM-RS ports among 4-7 or 6-11 for DM-RS configurations type 1 and type 2, respectively are scheduled for the UE and PT-RS is transmitted from the UE.

For PUSCH scheduled by DCI format 0 1, by activation DCI format 0 1 with CRC scrambled by CS-RNTI, or configured by configured grant Type 1 configuration, the UE shall assume the DM-RS code division multiplexing (CDM) groups indicated in Tables 7.3.1.1.2-6 to 7.3.1.1.2-23 of Clause 7.3.1.1 of [TS38.212] are not used for data transmission, where "1", "2" and "3" for the number of DM-RS CDM group(s) correspond to CDM group 0, {0,1 }, {0,1,2}, respectively.

For PUSCH scheduled by DCI format 0 0 or by activation DCI format 0 0 with CRC scrambled by CS-RNTI, the UE shall assume the number of DM-RS CDM groups without data is 1 which corresponds to CDM group 0 for the case of PUSCH with allocation duration of 2 or less OFDM symbols with transform precoding disabled, the UE shall assume that the number of DM-RS CDM groups without data is 3 which corresponds to CDM group {0,1,2} for the case of PUSCH scheduled by activation DCI format 0 0 and the dmrs-Type in DMRS-UplinkConfig equal to 'type2' and the PUSCH allocation duration being more than 2 OFDM symbols, and the UE shall assume that the number of DM-RS CDM groups without data is 2 which corresponds to CDM group {0,1 } for all other cases. For MsgA PUSCH transmission, if the UE is not configured with msgA- PUSCH-DMRS-CDM-group, the UE shall assume that 2 DM-RS CDM groups are configured. Otherwise, msgA-PUSCH-DMRS-CDM-group indicates which DM-RS CDM group to use from the set of {0, 1 } .

For MsgA PUSCH transmission, if the UE is not configured with msgA- PUSCH-NrofPorts, the UE shall assume that 4 ports are configured per DM-RS CDM group for double-symbol DM-RS. Otherwise, msgA-PUSCH-NrofPorts with value of 0 indicates the first port per DM-RS CDM group, while a value of 1 indicates the first two ports per DM-RS CDM group.

In one implementation of the present application, paging DCI can indicate

• Deactivating/deconfigure one or more activated CG PUSCH configuration

• Stopping a SDT-specific TAT or consider the SDT-specific TAT expired (for example, effectively forcing a UE to use only RACH procedure for SDT transmission or legacy RACH procedure).

In a further implementation, a network entity may flexibly change (e.g. dynamically change via DCI or medium access control (MAC) control element (CE)) a set of actually transmitted SS/PBCH blocks (SSBs) out of a set of predefined SSB candidate positions based on UEs’ spatial distribution (e.g., for RRC connected mode UEs) and predicted (or estimated) UE locations (e.g., knowledge of UE spatial distribution (e.g., office parks, residential area etc.) for different times of a day). For example, the network entity may estimate current UE locations/orientations using 3GPP/non-3GPP positioning technologies, 3GPP CSI reporting (e.g. Ll-RSRP, Ll- SINR reporting) and/or mobility measurement reporting, various sensors, e.g. radar and camera, predict future UE locations based on estimated UEs’ movement directions and speeds (additionally using artificial intelligence and/or machine learning), and adjust a SSB transmission pattern within a half frame accordingly.

In another implementation, a network entity may transmit a plurality of SSBs within a half frame with different periodicities. In one example, in response to a network entity determining that there is no or few RRC connected UEs served by a set of SSBs (i.e. DL Tx beams), e.g. based on UEs’ CSI reporting and/or there are very few UEs in locations related to the set of SSBs in a cell, the network entity can configure a longer periodicity (e.g. 20ms or longer) for the set of SSBs. In another example, when a network entity provides one or more TRS occasions, which are configured for RRC connected UEs and associated (e.g. quasi-co-located) with a set of SSBs, to RRC idle/inactive UEs in a cell, the network entity can configure a longer periodicity for the set of SSBs.

In an implementation, a network entity transmits a dynamic indication corresponding to information of time-domain positions of transmitted SSBs in an SSB burst and/or an indication corresponding to information of a plurality of SSB periodicities, each periodicity applicable to a subset of SSBs in an SSB burst (i.e. a set of SSBs within a half frame), e.g. via paging DCI (e.g. DCI format 1 0 with CRC scrambled by P-RNTI), paging early indication DCI (e.g. DCI format 2 7 in Rel-17 NR), and DCI format 1 0 with CRC scrambled by SI-RNTI.

Adaptation of SDT resources with adaptive SSB transmissions

In one embodiment, a UE assumes that at least one SDT resource, e.g. a CG PUSCH resource and/or a RACH resource, associated with a SSB with index i is not available, if the UE receives a dynamic indication of time domain positions of transmitted SSBs within an SSB burst indicating that the SSB with index i is not transmitted by a network entity for an associated indication validity duration. The associated indication validity duration may be predefined or configured as part of system information. In an example, a validity interval associated with a dynamic indication may be determined based on a radio frame and/or a slot where the UE receives the dynamic indication, e.g. starting from the radio frame and/or the slot until an end of the configured validity duration.

In one exemplary implementation, if a dynamic indication of time-domain positions of transmitted SSBs within an SSB burst is included in DCI format 1 0 with CRC scrambled by SI-RNTI in a current modification period, a UE considers that one or more SDT resources associated with SSBs indicated in the DCI as not being transmitted are unavailable from the start of the next modification period. The modification period boundaries are defined by system frame number (SFN) values for which SFN mod m = 0, where m is the number of radio frames comprising the modification period. The modification period is configured by system information. In alternative example implementation, the UE considers that one or more SDT resources associated with SSBs indicated in the DCI as not being transmitted are unavailable from the start of the current modification period.

In another exemplary implementation, if a dynamic indication of time-domain positions of transmitted SSBs within an SSB burst is included in DCI format 1 0 with CRC scrambled by P-RNTI received in a paging occasion of a current defaultPagingCycle (e.g., default DRX value broadcast in system information), a UE considers that one or more SDT resources associated with SSBs indicated in the DCI as not being transmitted are unavailable from a first frame of the next defaultPagingCycle . The defaultPagingCycle boundaries may be defined by SFN values for which (SFN+PF_offset) mod m = 0, where m is the number of radio frames comprising the defaultPagingCycle and PF offset denotes a frame offset of a starting Paging Frame. The defaultPagingCycle is configured by system information. In an alternative exemplary implementation, the UE considers that one or more SDT resources associated with SSBs indicated in the DCI as not being transmitted are unavailable from a first frame of the current defaultPagingCycle .

In yet another exemplary implementation, if a dynamic indication of timedomain positions of transmitted SSBs within an SSB burst is included in DCI format 2 7 detected in a current paging early indication (PEI) occasion that consists of a set of PDCCH monitoring occasions for DCI format 2 7, a UE considers that one or more SDT resources associated with SSBs indicated in the DCI as not being transmitted are unavailable from a start frame of the next PEI occasion. The start frame of the next PEI occasion is determined based on the parameter PEI-F offset (i.e. a number of frames from the start of a first paging frame of paging frames associated with the next PEI occasion to the start frame of the next PEI occasion). In an alternative exemplary implementation, the UE considers that one or more SDT resources associated with SSBs indicated in the DCI as not being transmitted are unavailable from a first paging frame of paging frames associated with the current PEI occasion. Dynamic availability indication for SDT resources

In an embodiment, when a UE detects a DCI format 1 0 with CRC scrambled by SI-RNTI in a current modification period, where the DCI includes a dynamic indication of availability of one or more SDT resources, the UE considers that the one or more SDT resources are available from the start of the next modification period for a validity duration. Alternatively, the UE considers that the one or more SDT resources are available from the start of the current modification period for the validity duration.

In an embodiment, when a UE detects a DCI format 1 0 with CRC scrambled by P-RNTI in a paging occasion of a current defaultPagingCycle, where the DCI includes a dynamic indication of availability of one or more SDT resources, the UE considers that the one or more SDT resources are available from a first frame of the next defaultPagingCycle for a validity duration. Alternatively, the UE considers that the one or more SDT resources are available from a first frame of the current defaultPagingCycle for the validity duration.

In an embodiment, when a UE detects a DCI format 2 7 with CRC scrambled by PEI-RNTI in a current PEI occasion, where the DCI includes a dynamic indication of availability of one or more SDT resources, the UE considers that the one or more SDT resources are available from a start frame of the next PEI occasion for a validity duration. Alternatively, the UE considers that the one or more SDT resources are available from a first paging frame of paging frames associated with the current PEI occasion for the validity duration.

In the above embodiments, the validity duration can be configured or predefined.

In one example, a UE is configured with a set of CG typel PUSCH configurations for SDT and detects a DCI indicating availability of a subset of CG- SDT configurations for a validity duration. The DCI includes a bitfield indicating the availability of a subset of CG-SDT configurations with bitmap-based indication (e.g. each bit corresponds to a CG configuration or a subset of CG configurations) or code- point based indication (e.g. each code-point corresponds to a CG configuration or a subset of CG configurations).

For example, a value of '1' for a bit of a bitmap in DCI indicates availability of an associated set of CG PUSCH resources (or an associated set of RACH occasions) for multiple of a number of frames, starting from a SFN determined from (SFN + PF_offsetmod7=/2 corresponding to a first frame of defaultPagingCycle that is associated with a PDCCH providing the DCI, where T is the number of radio frames comprising the defaultPagingCycle . A value of 'O' for a bit of the bitmap indicates no change to a current assumption for the availability or unavailability of the associated set of CG PUSCH resources (or the associated set of RACH occasions).

In Rel-17 NR, a UE in RRC INACTIVE state can transmit small amount of data based on a 2-step or 4-step random access procedure and/or based on configured grant (CG) type-1 physical uplink shared channel (PUSCH) transmission without resuming a RRC connection, which can reduce signaling overhead related to RRC connection setup and subsequent release procedures and may extend a UE battery life. One potential drawback of small data transmissions from UEs in RRC INACTIVE state is that a network should reserve time and frequency resources for random access channel (RACH) occasions and/or PUSCH occasions and continuously attempt to detect physical random access channel (PRACH) preambles and/or PUSCH demodulation reference signal (DM RS) sequences on configured RACH occasions and/or PUSCH occasions, which may increase network energy consumption.

The current application presents methods to enable small data transmission from an RRC INACTIVE UE in a network energy efficient manner.

Adaptation of SDT resources with adaptive SSB transmissions

• UE assumes that at least one small data transmission (SDT) resource associated with a SSB with index z is not available, if the UE receives a dynamic indication of time domain positions of transmitted SSBs within an SSB burst indicating that the SSB with index z is not transmitted by a network entity for an associated indication validity duration. Dynamic availability indication for SDT resources

• Availabilities of one or more SDT resources are indicated in DCI format 1 0 with CRC scrambled by SI-RNTI, DCI format 1 0 with CRC scrambled by P- RNTI, or DCI format 2 7 with CRC scrambled by PEI-RNTI with corresponding availability indication validity intervals.

In Rel-17 NR SDT procedure, CG type-1 resources and RACH resources are semi-statically configured for SDT initiation by a UE, and the CG resources are released upon expiry of an SDT-specific timing alignment (TA) timer. Thus, a network entity should continuously attempt to detect potential CG PUSCH transmissions from the UE, when the SDT-specific TA timer value is set to be large. If the SDT-specific TA timer value is set to be small, the UE may often not be able to use the CG type-1 resources due to timer expiry and may have to initiate SDT via RACH resources or cannot use SDT (if RACH resources for SDT are not configured).

In the proposed methods, the UE would generally not use SDT resources associated with SS/PBCH blocks (SSBs), which have been dynamically indicated as not being transmitted by gNB, and accordingly, gNB does not have to monitor those SDT resources. Further, a dynamic indication of availability of SDT resources can further allow gNB to dynamically turn on/off monitoring of SDT resources.

FIG. 2 illustrates a flow diagram 200 of a method in a user equipment. The method includes receiving 202 a first indication of time domain positions of a first set of synchronization signal and physical broadcast channel blocks in a first synchronization signal and physical broadcast channel block burst, via a higher signaling layer, wherein the first indication configures a transmission of a synchronization signal and physical broadcast channel block with a first index. A second indication of time domain positions of a second set of synchronization signal and physical broadcast channel blocks is received 204 in a second synchronization signal and physical broadcast channel block burst, wherein the second indication indentifies the unavailability of the transmission of the synchronization signal and physical broadcast channel block with the first index during a period of unavailability associated with a corresponding indication validity interval. A small data transmission is transmitted 206 during the period of unavailability associated with the indication validity interval using a small data transmission resource of a plurality of configured small data transmission resources, wherein the small data transmission resource is not a part of a set of small data transmission resources associated with the synchronization signal and physical broadcast channel block with the first index.

In some instances, the set of small data transmission resources associated with the synchronization signal and physical broadcast channel block with the first index can be determined based on a mapping between each synchronization signal and physical broadcast channel block of the first set of synchronization signal and physical broadcast channel blocks, and each set of small data transmission resources of the plurality of configured small data transmission resources.

In some instances, the method can further include determining the period of unavailability based on the indication validity interval received as part of the second indication.

In some instances, the second indication can be received in downlink control information.

In some instances, the indication validity interval can be determined based on timing information corresponding to when the second indication is received, and an indication validity duration. In some of these instances, the indication validity duration can be predefined. In other of these instances, the method can further include receiving information of the indication validity duration. In still further of these instances, the period of unavailability can be determined based on a system information modification period where the second indication is received. Further yet, the period of unavailability can be determined based on a default paging cycle where the second indication is received. Still further yet, the period of unavailability can be determined based on a paging early indication occasion where the second indication is received.

In some instances, the method can further includes determining a plurality of sets of small data transmission resources, each set of small data transmission resources being associated with each synchronization signal and physical broadcast channel block of the first set of synchronization signal and physical broadcast channel blocks, and receiving a dynamic indication indicating availability of a subset of small data transmission resources of each set of small data transmission resources. In some of these instances the dynamic indication indicating availability can be included as part of a third indication received during a system information modification period corresponding to the indication validity interval associated with the second indication. In other of these instances, the dynamic indication indicating availability can be included as part of downlink control information received during a paging occasion. In still further of these instances, the dynamic indication indicating availability can be included as part of downlink control information received during a paging early indication occasion. Further yet, the dynamic indication indicating availability can be included in downlink control information activating a configured grant small data transmission configuration. Still further yet, the dynamic indication indicating availability can include a bitmap-based indication indicating availability of respective sets of small data transmission resources.

In instances where the dynamic indication indicating availability includes a bitmap-based indication, a first predefined bit map value in the bitmap-based indication associated with the dynamic indication indicating availability, can indicate an availability of an associated set of small data transmission resources. In same or other instances, a second predefined bit map value in the bitmap-based indication associated with the dynamic indication indicating availability, can indicate no change in an availability of an associated set of small data transmission resources.

FIG. 3 illustrates a flow diagram 300 of a method in a network entity. The method includes transmitting 302 a first indication of time domain positions of a first set of synchronization signal and physical broadcast channel blocks in a first synchronization signal and physical broadcast channel block burst, via a higher signaling layer, wherein the first indication configures a transmission of a synchronization signal and physical broadcast channel block with a first index. A second indication of time domain positions of a second set of synchronization signal and physical broadcast channel blocks is transmitted 304 in a second synchronization signal and physical broadcast channel block burst, wherein the second indication indentifies to one or more user equipment, the unavailability of the transmission of the synchronization signal and physical broadcast channel block with the first index during a period of unavailability associated with a corresponding indication validity interval. The monitoring is discontinued 306 for a small data transmission from the one or more user equipment during the period of unavailability associated with the indication validity interval, of a set of small data transmission resources associated with the synchronization signal and physical broadcast channel block with the first index.

It should be understood that, notwithstanding the particular steps as shown in the present application and any of the figures, a variety of additional or different steps can be performed depending upon the embodiment, and one or more of the particular steps can be rearranged, repeated or eliminated entirely depending upon the embodiment. Also, some of the steps performed can be repeated on an ongoing or continuous basis simultaneously while other steps are performed. Furthermore, different steps can be performed by different elements or in a single element of the disclosed embodiments. Additionally, a network entity, such as a base station, transmission and reception point, or other network entity, can perform reciprocal operations of a UE. For example, the network entity can transmit signals received by the UE and can receive signals transmitted by the UE. The network entity can also process and operate on sent and received signals.

FIG. 4 is an example block diagram of an apparatus 400, such as the wireless communication device 110, according to a possible embodiment. The apparatus 400 can include a housing 410, a controller 420 within the housing 410, audio input and output circuitry 430 coupled to the controller 420, a display 440 coupled to the controller 420, a transceiver 450 coupled to the controller 420, an antenna 455 coupled to the transceiver 450, a user interface 460 coupled to the controller 420, a memory 470 coupled to the controller 420, and a network interface 480 coupled to the controller 420. The apparatus 400 can perform the methods described in all the embodiments.

The display 440 can be a viewfinder, a liquid crystal display (LCD), a light emitting diode (LED) display, a plasma display, a projection display, a touch screen, or any other device that displays information. The transceiver 450 can include a transmitter and/or a receiver. The audio input and output circuitry 430 can include a microphone, a speaker, a transducer, or any other audio input and output circuitry. The user interface 460 can include a keypad, a keyboard, buttons, a touch pad, a joystick, a touch screen display, another additional display, or any other device useful for providing an interface between a user and an electronic device. The network interface 480 can be a Universal Serial Bus (USB) port, an Ethernet port, an infrared transmitter/receiver, an IEEE 1394 port, a WLAN transceiver, or any other interface that can connect an apparatus to a network, device, or computer and that can transmit and receive data communication signals. The memory 470 can include a random access memory, a read only memory, an optical memory, a solid state memory, a flash memory, a removable memory, a hard drive, a cache, or any other memory that can be coupled to an apparatus.

The apparatus 400 or the controller 420 may implement any operating system, such as Microsoft Windows®, UNIX®, or LINUX®, Android™, or any other operating system. Apparatus operation software may be written in any programming language, such as C, C++, Java or Visual Basic, for example. Apparatus software may also run on an application framework, such as, for example, a Java® framework, a .NET® framework, or any other application framework. The software and/or the operating system may be stored in the memory 470 or elsewhere on the apparatus 400. The apparatus 400 or the controller 420 may also use hardware to implement disclosed operations. For example, the controller 420 may be any programmable processor. Disclosed embodiments may also be implemented on a general-purpose or a special purpose computer, a programmed microprocessor or microcontroller, peripheral integrated circuit elements, an application-specific integrated circuit or other integrated circuits, hardware/electronic logic circuits, such as a discrete element circuit, a programmable logic device, such as a programmable logic array, field programmable gate-array, or the like. In general, the controller 420 may be any controller or processor device or devices capable of operating an apparatus and implementing the disclosed embodiments. Some or all of the additional elements of the apparatus 400 can also perform some or all of the operations of the disclosed embodiments.

The method of this disclosure can be implemented on a programmed processor. However, the controllers, flowcharts, and modules may also be implemented on a general purpose or special purpose computer, a programmed microprocessor or microcontroller and peripheral integrated circuit elements, an integrated circuit, a hardware electronic or logic circuit such as a discrete element circuit, a programmable logic device, or the like. In general, any device on which resides a finite state machine capable of implementing the flowcharts shown in the figures may be used to implement the processor functions of this disclosure.

While this disclosure has been described with specific embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art. For example, various components of the embodiments may be interchanged, added, or substituted in the other embodiments. Also, all of the elements of each figure are not necessary for operation of the disclosed embodiments. For example, one of ordinary skill in the art of the disclosed embodiments would be enabled to make and use the teachings of the disclosure by simply employing the elements of the independent claims. Accordingly, embodiments of the disclosure as set forth herein are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit and scope of the disclosure.

In this document, relational terms such as "first," "second," and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. The phrase "at least one of," "at least one selected from the group of," or "at least one selected from" followed by a list is defined to mean one, some, or all, but not necessarily all of, the elements in the list. The terms "comprises," "comprising," "including," or any other variation thereof, are intended to cover a nonexclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by "a," "an," or the like does not, without more constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element. Also, the term "another" is defined as at least a second or more. The terms "including," "having," and the like, as used herein, are defined as "comprising." Furthermore, the background section is written as the inventor's own understanding of the context of some embodiments at the time of filing and includes the inventor's own recognition of any problems with existing technologies and/or problems experienced in the inventor's own work.

Claims

WHAT IS CLAIMED IS:

1. A method in a user equipment, the method comprising: receiving a first indication of time domain positions of a first set of synchronization signal and physical broadcast channel blocks in a first synchronization signal and physical broadcast channel block burst, via a higher signaling layer, wherein the first indication configures a transmission of a synchronization signal and physical broadcast channel block with a first index; receiving a second indication of time domain positions of a second set of synchronization signal and physical broadcast channel blocks in a second synchronization signal and physical broadcast channel block burst, wherein the second indication indentifies the unavailability of the transmission of the synchronization signal and physical broadcast channel block with the first index during a period of unavailability associated with a corresponding indication validity interval; and transmitting a small data transmission during the period of unavailability associated with the indication validity interval using a small data transmission resource of a plurality of configured small data transmission resources, wherein the small data transmission resource is not a part of a set of small data transmission resources associated with the synchronization signal and physical broadcast channel block with the first index.

2. The method of claim 1, wherein the set of small data transmission resources associated with the synchronization signal and physical broadcast channel block with the first index is determined based on a mapping between each synchronization signal and physical broadcast channel block of the first set of synchronization signal and physical broadcast channel blocks, and each set of small data transmission resources of the plurality of configured small data transmission resources.

3. The method of claim 1 further comprising determining the period of unavailability based on the indication validity interval received as part of the second indication.

4. The method of claim 1, wherein the second indication is received in downlink control information.

5. The method of claim 1, wherein the indication validity interval is determined based on timing information corresponding to when the second indication is received, and an indication validity duration.

6. The method of claim 5, wherein the indication validity duration is predefined.

7. The method of claim 5, further comprising receiving information of the indication validity duration.

8. The method of claim 5, wherein the period of unavailability is determined based on a system information modification period where the second indication is received.

9. The method of claim 5, wherein the period of unavailability is determined based on a default paging cycle where the second indication is received.

10. The method of claim 5, wherein the period of unavailability is determined based on a paging early indication occasion where the second indication is received.

11. The method of claim 1, further comprising: determining a plurality of sets of small data transmission resources, each set of small data transmission resources being associated with each synchronization signal and physical broadcast channel block of the first set of synchronization signal and physical broadcast channel blocks; and receiving a dynamic indication indicating availability of a subset of small data transmission resources of each set of small data transmission resources.

12. The method of claim 11, wherein the dynamic indication indicating availability is included as part of a third indication received during a system information modification period corresponding to the indication validity interval associated with the second indication.

13. The method of claim 11, wherein the dynamic indication indicating availability is included as part of downlink control information received during a paging occasion.

14. The method of claim 11, wherein the dynamic indication indicating availability is included as part of downlink control information received during a paging early indication occasion.

15. The method of claim 11, wherein the dynamic indication indicating availability is included in downlink control information activating a configured grant small data transmission configuration.

16. The method of claim 11, wherein the dynamic indication indicating availability includes a bitmap-based indication indicating availability of respective sets of small data transmission resources.

17. The method of claim 16, wherein a first predefined bit map value in the bitmap-based indication associated with the dynamic indication indicating availability, indicates an availability of an associated set of small data transmission resources.

18. The method of claim 16, wherein a second predefined bit map value in the bitmap-based indication associated with the dynamic indication indicating availability, indicates no change in an availability of an associated set of small data transmission resources.

19. A user equipment for communicating within a network, the user equipment comprising: a controller; and a transceiver for receiving a first indication of time domain positions of a first set of synchronization signal and physical broadcast channel blocks in a first synchronization signal and physical broadcast channel block burst, via a higher signaling layer, wherein in response to receiving the first indication, the controller configures a transmission of a synchronization signal and physical broadcast channel block with a first index; wherein the transceiver further receives a second indication of time domain positions of a second set of synchronization signal and physical broadcast channel blocks in a second synchronization signal and physical broadcast channel block burst, wherein from the second indication the controller indentifies the unavailability of the transmission of the synchronization signal and physical broadcast channel block with the first index during a period of unavailability associated with a corresponding indication validity interval; and wherein the transceiver transmits a small data transmission during the period of unavailability associated with the indication validity interval using a small data transmission resource of a plurality of configured small data transmission resources, wherein the small data transmission resource is identified by the controller as not being a part of a set of small data transmission resources associated with the synchronization signal and physical broadcast channel block with the first index.

20. A method in a network entity, the method comprising: transmitting a first indication of time domain positions of a first set of synchronization signal and physical broadcast channel blocks in a first synchronization signal and physical broadcast channel block burst, via a higher signaling layer, wherein the first indication configures a transmission of a synchronization signal and physical broadcast channel block with a first index; transmitting a second indication of time domain positions of a second set of synchronization signal and physical broadcast channel blocks in a second synchronization signal and physical broadcast channel block burst, wherein the second indication indentifies to one or more user equipment, the unavailability of the transmission of the synchronization signal and physical broadcast channel block with the first index during a period of unavailability associated with a corresponding indication validity interval; and discontinuing the monitoring for a small data transmission from the one or more user equipment during the period of unavailability associated with the indication validity interval, of a set of small data transmission resources associated with the synchronization signal and physical broadcast channel block with the first index.