WO2022236546A1

WO2022236546A1 - Method for controlling power headroom reporting for small data transmission, user equipment, and base station

Info

Publication number: WO2022236546A1
Application number: PCT/CN2021/092684
Authority: WO
Inventors: Hejun WANG; Jia SHENG
Original assignee: Tcl Communication (Ningbo) Co., Ltd.
Priority date: 2021-05-10
Filing date: 2021-05-10
Publication date: 2022-11-17
Also published as: CN116889039A

Abstract

A method for controlling power headroom report for small data transmission (SDT) operable in a user equipment (UE) includes: triggering a power headroom report (PHR) upon detecting subsequent data transmitting information; transmitting the PHR to a base station; receiving uplink (UL) scheduling information from the base station; and transmitting subsequent data based on the UL scheduling information. Optionally, the UL scheduling information may be determined based on the PHR.

Description

Method for Controlling Power Headroom Reporting for Small Data Transmission, User Equipment, and Base Station

Technical Field

The present disclosure relates to the field of communication systems, and more particularly, to a method for controlling power headroom reporting for small data transmission, a user equipment and a base station.

Background Art

Wireless communication systems and networks have developed towards being a broadband and mobile system. In cellular wireless communication systems, user equipment (UE) is connected by a wireless link to a radio access network (RAN) . The RAN comprises a set of base stations (BSs) which provide wireless links to the UEs located in cells covered by the base station, and an interface to a core network (CN) which provides overall network control. As will be appreciated the RAN and CN each conduct respective functions in relation to the overall network. The 3rd Generation Partnership Project (3GPP) has developed the so-called Long Term Evolution (LTE) system, namely, an Evolved Universal Mobile Telecommunication System Territorial Radio Access Network, (E-UTRAN) , for a mobile access network where one or more macro-cells are supported by a base station known as an eNodeB or eNB (evolved NodeB) . More recently, LTE is evolving further towards the so-called 5G or NR (New Radio) systems where one or more cells are supported by a base station known as a gNB.

Ultra-reliable low-latency communication (URLLC) , is one of several different types of use cases supported by the 5G NR standard, as stipulated by 3GPP Release 15. URLLC is a communication service for successfully delivering packets with stringent requirements, particularly in terms of availability, latency, and reliability. URLLC is developed to support the emerging applications and services, such as wireless control and automation in industrial factory environments, inter-vehicular communications for improved safety and efficiency, and the tactile internet. Thus, URLLC is important for 5G as it supports verticals bringing new business to the whole telecommunication industry.

One of the key features of URLLC is low latency. Low latency allows a network to be optimized for processing incredibly large amounts of data with minimal delay or latency. URLLC requires a quality of service (QoS) totally different from mobile broadband services. In addition, small and infrequent data traffic is one of the important scenarios for the URLLC. For example, smart phone applications require traffic from Instant Messaging services (whatsapp, QQ, wechat, etc) , heart-beat/keep-alive traffic from IM/email clients, and pushing notifications from various applications. Furthermore, wearable devices require periodic positioning information, industrial wireless sensor networks require transmitting temperature, pressure readings periodically or in an event triggered manner, smart meters and smart meter networks require sending periodic meter readings. NR supports RRC_INACTIVE state and UEs with infrequent (periodic and/or non-periodic) data transmission are generally maintained by the network in the RRC_INACTIVE state. Until Rel-16, the RRC_INACTIVE state does not support data transmission. Hence, the UE has to resume the connection (i.e. return to RRC_CONNECTED state) for any downlink (DL) and uplink (UL) data. Connection setup and subsequent release to RRC_INACTIVE state happens for each data transmission. However, transmitting small and infrequent data packets results in unnecessary power consumption and signaling overhead.

For small data packets, signaling overhead from RRC_INACTIVE state of UEs is a general problem and will become a critical issue with more UEs in NR, not only for network performance and efficiency but also for the UE battery performance. In general, any device that has intermittent small data packets in RRC_INACTIVE state will benefit from enabling small data transmission in RRC_INACTIVE state. Transmission of small data in UL, subsequent transmission of small data in UL and DL and the state transition decisions should be under network control.

Upon initiation of connection resume for SDT (Small Data Transmission) , UE applies default MAC Cell Group configuration. Then, for SDT, a Power Headroom Report (PHR) is triggered and included ahead of Dedicated Traffic Channel (DTCH) service data unit (SDU) , which may be not optional for SDT. The PHR is proposed to be supported for SDT, especially for the subsequent SDT procedure.

Technical Problem

PHR is useful for SDT, at least for subsequent data transmission. Thus, a mechanism of PHR should be designed for the SDT, especially for the subsequent SDT.

Technical Solution

An object of the present disclosure is to propose a method for controlling power headroom report for small data transmission (SDT) operable in a user equipment (UE) includes: triggering a power headroom report (PHR) upon detecting subsequent data transmitting information; transmitting the PHR to a base station.

A second aspect of the disclosure provides a method for controlling power headroom report for small data transmission operable in a base station. The method includes: triggering a power headroom report (PHR) upon detecting subsequent data transmitting information.

The disclosed method may be implemented in a chip. The chip may include a processor, configured to call and run a computer program stored in a memory, to cause a device in which the chip is installed to execute the disclosed method.

The disclosed method may be programmed as computer executable instructions stored in non-transitory computer readable medium. The non-transitory computer readable medium, when loaded to a computer, directs a processor of the computer to execute the disclosed method. The non-transitory computer readable medium may comprise at least one from a group consisting of: a hard disk, a CD-ROM, an optical storage device, a magnetic storage device, a Read Only Memory, a Programmable Read Only Memory, an Erasable Programmable Read Only Memory, EPROM, an Electrically Erasable Programmable Read Only Memory and a Flash memory.

The disclosed method may be programmed as computer program product, that causes a computer to execute the disclosed method.

The disclosed method may be programmed as computer program, that causes a computer to execute the disclosed method.

Advantageous Effects

Embodiments of the disclosure are provided to a method for controlling power headroom report for small data transmission (SDT) operable in a user equipment (UE) including: triggering a power headroom report (PHR) upon detecting subsequent data transmitting information; transmitting the PHR to a base station, and to a method for controlling power headroom report for small data transmission operable in a base station including: triggering a power headroom report (PHR) upon detecting subsequent data transmitting information. The present disclosure improves not only network performance and efficiency but also the UE battery performance.

Description of Drawings

In order to more clearly illustrate the embodiments of the present disclosure or related art, the following figures will be described in the embodiments are briefly introduced. It is obvious that the drawings are merely some embodiments of the present disclosure, a person having ordinary skill in this field can obtain other figures according to these figures without paying the premise.

FIG. 1 illustrates a relation between logical communication link, communication service and application.

FIG. 2 illustrates a flow of a method of controlling power headroom report for small data transmission according to a first embodiment of the present disclosure.

FIG. 3 illustrates a flow of a method of controlling power headroom report for small data transmission according to a second embodiment of the present disclosure.

FIG. 4 illustrates a flow of a method of controlling power headroom report for small data transmission according to a third embodiment of the present disclosure.

FIG. 5 illustrates a flow of a method of controlling power headroom report for small data transmission according to a fourth embodiment of the present disclosure.

FIG. 6 illustrates a flow of a method of controlling power headroom report for small data transmission according to a fifth embodiment of the present disclosure.

FIG. 7 illustrates a flow of a method of controlling power headroom report for small data transmission according to a sixth embodiment of the present disclosure.

FIG. 8 illustrates a flow of a method of controlling power headroom report for small data transmission according to a seventh embodiment of the present disclosure.

FIG. 9 illustrates a flow of a method of controlling power headroom report for small data transmission according to an eighth embodiment of the present disclosure.

FIG. 10 illustrates a flow of a method of controlling power headroom report for small data transmission according to a ninth embodiment of the present disclosure.

FIG. 11 illustrates a flow of a method of controlling power headroom report for small data transmission according to a tenth embodiment of the present disclosure.

FIG. 12 illustrates a flow of a method of controlling power headroom report for small data transmission according to an eleventh embodiment of the present disclosure.

FIG. 13 illustrates a flow of a method of controlling power headroom report for small data transmission according to a twelfth embodiment of the present disclosure.

FIG. 14 illustrates a flow of a method of controlling power headroom report for small data transmission according to a thirteenth embodiment of the present disclosure.

FIG. 15 is a block diagram of an example system for wireless communication according to an embodiment of the present disclosure.

DETAILED DESCRIPTION OF EMBODIMENTS

Embodiments of the disclosure are described in detail with the technical matters, structural features, achieved objects, and effects with reference to the accompanying drawings as follows. Specifically, the terminologies in the embodiments of the present disclosure are merely for describing the purpose of the certain embodiment, but not to limit the disclosure.

Related Agreements

3GPP RAN2#111-e Agreements

Small data transmission with RRC message is supported as baseline for RA-based and CG based schemes.

The 2-step RACH or 4-step RACH should be applied to RACH based uplink small data transmission in RRC_INACTIVE.

The uplink small data can be sent in MSGA of 2-step RACH or msg3 of 4-step RACH.

Small data transmission is configured by the network on a per DRB basis.

Data volume threshold is used for the UE to decide whether to do SDT or not.

UL/DL transmission following UL SDT without transitioning to RRC_CONNECTED is supported.

When UE is in RRC_INACTIVE, it should be possible to send multiple UL and DL packets as part of the same SDT mechanism and without transitioning to RRC_CONNECTED on dedicated grant.

3GPP RAN2#112-e Agreements

For both RACH and CG based solutions, upon initiating RESUME procedure for SDT initiation (i.e. for first SDT transmission) , the UE 10 may re-establish at least the SDT PDCP entities and resume the SDT DRBs that are configured for small data transmission (along with the SRB1) .

The configuration of configured grant resource for UE uplink small data transfer is contained in the RRCRelease message.

The configuration of configured grant resource can include one type 1 CG configuration.

The UE can use configured grant based small data transfer if at least the following criteria is fulfilled

(1) user data is smaller than the data volume threshold;

(2) configured grant resource is configured and valid;

(3) UE has valid TA.

3GPP RAN2#113-e Agreements

CG-SDT resource configuration is provided to UEs in RRC_Connected only within the RRCRelease message, i.e. no need to also include it in RRCReconfiguration message.

RRCRelease message is used to reconfigure or release the CG-SDT resources while UE is in RRC_INACTIVE.

For CG-SDT the subsequent data transmission can use the CG resource or DG (i. e dynamic grant addressed to UE’s C-RNTI) .

If CG-SDT resources are configured on the selected UL carrier and are valid, then CG-SDT is chosen. Otherwise,

· If 2 step RA-SDT resources are configured on the UL carrier and criteria to select 2 step RA SDT is met, then 2 step RA-SDT is chosen

· else If 4 step RA-SDT resources are configured on the UL carrier and criteria to select 4 step RA SDT is met, then 4 step RA-SDT is chosen

· else UE does not perform SDT (i.e. perform non-SDT resume procedure)

· If both 2 step RA-SDT and 4 step RA-SDT resources are configured on the UL carrier, RA type selection is performed based on RSRP threshold.

3GPP RAN2#113bis-e Agreements

Switching from SDT to non-SDT is supported.

FFS Switching from CG-SDT to RA-SDT is not allowed.

PHR functionality is supported for SDT.

CG-SDT resources can be configured at the same time on NUL and SUL.

Implicit release of CG-SDT resource is not supported.

UE start a window after CG/DG transmission for CG-SDT.

Support retransmission by dynamic grant for CG-SDT.

With reference to FIG. 1, a telecommunication system including a UE 10, a base station 20, and a network entity device 30. Connections between devices and device components are shown as lines and arrows in the Figures. The UE 10 may include a processor 11, a memory 12, and a transceiver 13. The base station 20 may include a processor 201, a memory 202, and a transceiver 203a. The network entity device 300 may include a processor 301, a memory 302, and a transceiver 303. Each of the

processors

11, 201, and 301 may be configured to implement proposed functions, procedures and/or methods described in the description. Layers of radio interface protocol may be implemented in the

processors

11, 201, and 301. Each of the

memory

12, 202, and 302 operatively stores a variety of program and information to operate a connected processor. Each of the

transceiver

13, 203, and 303 is operatively coupled with a connected processor, transmits and/or receives radio signals or wireline signals. The base station 20 may be a base station such as an eNB, a gNB, or one of other types of radio nodes, and may configure radio resources for the UE 10.

Each of the

processor

11, 201, and 301 may include an application-specific integrated circuits (ASICs) , other chipsets, logic circuits and/or data processing devices. Each of the

memory

12, 202, and 302 may include a read-only memory (ROM) , a random access memory (RAM) , a flash memory, a memory card, a storage medium and/or other storage devices. Each of the

transceiver

13, 203, and 303 may include baseband circuitry and radio frequency (RF) circuitry to process radio frequency signals. When the embodiments are implemented in software, the techniques described herein can be implemented with modules, procedures, functions, entities and so on, that perform the functions described herein. The modules can be stored in a memory and executed by the processors. The memory can be implemented within a processor or external to the processor, in which those can be communicatively coupled to the processor via various means are known in the art.

The network entity device 300 may be a node in a CN. CN may include LTE CN or 5G core (5GC) which includes user plane function (UPF) , session management function (SMF) , mobility management function (AMF) , unified data management (UDM) , policy control function (PCF) , control plane (CP) /user plane (UP) separation (CUPS) , authentication server (AUSF) , network slice selection function (NSSF) , and the network exposure function (NEF) .

Embodiment 1

Please refer to FIG. 2. FIG. 2 illustrates a flow of a method of controlling power headroom report for small data transmission according to an embodiment of the present disclosure. The method of controlling power headroom report for small data transmission operable in the UE 10 includes steps as depicted in the following blocks. For the SDT procedure, especially the SDT with subsequent data, it is beneficial for the UL scheduling (e.g. Configured Grant and/or Dynamic Grant) and transmission power control to measure the path loss change and report the power headroom to the base station 20.

During or after the first phase (i.e. the first UL small data transmission stage) of the small data transmission, if there is subsequent data arrival, or Buffer Status Report (BSR) generated, or data arrival indication indicate that there is new uplink data to be transmitted, Power headroom report (PHR) is triggered for the UE 10 to report the PHR related information to the base station 20.Power headroom indicates how much transmission power left for the UE 10 to use in addition to the power being used by current transmission. It can be described by a simple formula as below.

Power Headroom = UE Max Transmission Power -PUSCH Power

PHR is a type of MAC CE (MAC Control Element) that report the headroom between the current UE transmission power (estimated power) and the nominal power. The base station 20 use this report value to estimate how much uplink bandwidth the UE 10 can use for a specific subframe. Since the more resource block the UE 10 is using, the higher UE transmission power gets, but the UE transmission power should not exceed the max power defined in the specification. So UE 10 cannot use much resource block (bandwidth) if it does not have enough power headroom.

Optionally, the UE assistance information and/or the subsequent data arrival information (e.g. BSR) may be transmitted to the base station 20 in addition to the PHR. So that the base station 20 performs the UL scheduling of the subsequent small data transmission for the UE, including Configured Grant and/or Dynamic Grant and/or UL transmission Power configuration, etc.

The SDT procedure, including the first SDT phase (the first UL transmission) and the second SDT phase (the subsequent UL transmission) if there is subsequent UL data arrival, may be RA-based SDT (4-step RA-based SDT and/or 2-step RA-based SDT) and/or the CG-based SDT. The second phase is optional in the SDT procedure.

The PHR procedure can be triggered implicitly by the subsequent data arrival/BSR/data arrival indication. This is to say that if there is subsequent data arrival or if there is BSR or if there is indication indicate that there is new data arrived, then the PHR shall be triggered, and the UE 10 may send the PHR related information to the base station 20. Otherwise, the UE 10 may not perform PHR procedure.

In another way, the PHR can be triggered and/or cancelled by the base station 20 explicitly, namely the base station 20 shall send indication to the UE indicating the UE to perform or cancel the PHR procedure. If the base station 20 send indication to the UE before or during the SDT procedure indicating the UE to perform PHR, the UE 10 may perform PHR procedure regardless of whether there is subsequent data arrival. Or alternatively, the UE 10 may determine whether to perform PHR procedure based on whether there is subsequent data arrival/BSR, i.e. if there is subsequent data arrival/BSR, then the UE 10 may perform PHR procedure, otherwise the UE 10 may not perform PHR procedure.

If the base station 20 send indication to the UE indicating the UE not to perform PHR procedure, the UE 10 may not perform PHR procedure or the UE 10 may cancel the PHR procedure, regardless whether there is subsequent data arrival/BSR. Or alternatively, the UE 10 may not perform PHR procedure until there is subsequent data to be transmitted.

Whether the UE 10 performing PHR procedure can be determined by any combination of at least one of the indications or triggers, including implicit or/and explicit instructions, etc.

Referring to FIG. 2, at Step 200, SDT preparation and first phase SDT are introduced. The SDT procedure can be RA-based SDT (including 4-step RA-based SDT and 2-step RA-based SDT) and CG-based SDT. For RA-based SDT, the preparation may include the procedures performed before the RA-based SDT is performed, e.g., carrier selection (Supplementary UL carrier and normal UL carrier) , beam selection, etc. The Supplementary UL (SUL) carrier can be configured as a complement to the normal UL (NUL) carrier. Switching between the NUL carrier and the SUL carrier means that the UL transmissions move from one carrier to the other carrier.

For CG-based SDT, the preparation may include the procedures performed before the CG-based UL transmission is performed, e.g., UL scheduling (e.g., CG, DG) , carrier selection, etc. The first phase SDT means the first uplink transmission of the small data, to be distinguished with the subsequent small data transmission. An indication may be transmitted to the UE 10 from the base station 20 during, before or after the first UL data transmission indicating the UE 10 to perform the PHR or not to perform PHR or to cancel PHR procedure.

At Step 201, subsequent data arrival/BSR/new data arrival indication indicating to the UE 10 that there is new UL data to be transmitted trigger UE 10 to perform PHR procedure. Subsequent data arrival and/or BSR and/or new data arrival indication shall indicate the UE 10 to perform PHR procedure. The subsequent data arrival may occur before, during or after the first uplink transmission. The UE 10 action of whether and how to perform the PHR procedure may be configured by the base station 20. The base station 20 commands the UE 10 not to perform PHR or cancel the PHR procedure.

At Step 202, UE 10 performs PHR procedure and sends PHR related information to the base station 20. The UE 10 performs PHR and sends PHR related information to the base station 20.The UE assistance information and/or the BSR may be sent to the base station 20 with the PHR optionally.

At Step 203, SDT is terminated. The UE 10 finishes the SDT procedure and goes back to the RRC_INACTIVE state. It may be the end of the first phase of the SDT or the second phase of the SDT. Namely the SDT termination can be the end of the first uplink transmission of the SDT procedure, or it can be the end of the subsequent SDT procedure. For the CG-based SDT, the UE 10 finishes the first uplink transmission over the Configured Grant and go back to RRC_INACTIVE state.

Embodiment 2

Please refer to FIG. 3. FIG. 3 illustrates a flow of a method of controlling power headroom report for small data transmission according to a second embodiment of the present disclosure. This embodiment provides the operation of the subsequent data transmission. After receiving the PHR and/or BSR from the UE 10, the base station 20 sends the UE 10 with scheduling information for the subsequent data transmission. Then the UE 10 may perform the subsequent uplink transmission with the scheduling information. The UE 10 is in RRC_INACTIVE state.

The scheduling information may include the UL Grant configuration, e.g. Configured Grant, Dynamic Grant, etc. Then the UE 10 may transmit the subsequent to the base station 20 with the UL Grant.

The scheduling information may include the TPC command, then the UE 10 may perform the subsequent SDT with the transmission power configured as the TPC command indicated.

Both the UL Grant configuration and the TPC command may be included in the scheduling information. And the UE 10 may perform the subsequent uplink transmission with the UL Grant configuration and with the transmission power configured as the TPC command indicated.

At Step 300, SDT preparation and first phase SDT are introduced. The SDT procedure can be RA-based SDT (including 4-step RA-based SDT and 2-step RA-based SDT) and CG-based SDT. For RA-based SDT, the preparation may include the procedures performed before the RA-based SDT is performed, e.g., carrier selection (Supplementary UL carrier and normal UL carrier) , beam selection, etc. The Supplementary UL (SUL) carrier can be configured as a complement to the normal UL (NUL) carrier. Switching between the NUL carrier and the SUL carrier means that the UL transmissions move from one carrier to the other carrier.

At Step 301, subsequent data arrival and/or BSR and/or new data arrival indication indicating to the UE 10 that there is new UL data to be transmitted trigger/indicate the UE 10 to perform PHR procedure. The subsequent data arrival may occur before, during or after the first uplink transmission. The UE 10 action of whether and how to perform the PHR procedure may be configured by the base station 20. The base station 20 may command the UE 10 not to perform PHR or cancel the PHR procedure.

At Step 302, UE 10 performs PHR procedure and sends PHR related information to the base station 20. The UE assistance information and/or the BSR may be sent to the base station 20 too, optionally.

At Step 303, after receiving the PHR information from the UE 10, the base station 20 sends uplink grant configuration to the UE 10 for the subsequent uplink transmission. The base station 20 may generate the uplink grant configuration for the UE 10 based on the PHR from the UE 10. The uplink grant configuration may be the configured grant or dynamic grant. The uplink grant configuration may include the radio resource allocation configuration and/or modulation and coding scheme (MCS) configuration for the subsequent uplink transmission.

At Step 304, the first phase SDT terminated. For the CG-based SDT, it means the UE 10 finishes the first uplink transmission over the configured grant and goes back to RRC_INACTIVE state. For the RA-based SDT, it means the UE 10 finishes the RRC resume procedure of the SDT and goes back to RRC_INACTIVE state. The order of step 303 and step 304 can be reversed.

At Step 305, the UE 10 performs subsequent uplink transmission utilizing the uplink grant information received from the base station 20. For the case that the uplink grant includes the radio resource allocation configuration and/or the MCS configuration, the UE 10 may perform the subsequent uplink transmission with the resource and MCS configured as the uplink grant configuration indicated.

Please refer to FIG. 4. FIG. 4 illustrates a flow of a method of controlling power headroom report for small data transmission according to a third embodiment of the present disclosure.

At Step 400, SDT preparation and first phase SDT are introduced. The SDT procedure can be RA-based SDT (including 4-step RA-based SDT and 2-step RA-based SDT) and CG-based SDT. For RA-based SDT, the preparation may include the procedures performed before the RA-based SDT is performed, e.g., carrier selection (Supplementary UL carrier and normal UL carrier) , beam selection, etc. The Supplementary UL (SUL) carrier can be configured as a complement to the normal UL (NUL) carrier. Switching between the NUL carrier and the SUL carrier means that the UL transmissions move from one carrier to the other carrier.

At Step 401, subsequent data arrival and/or BSR and/or new data arrival indication indicating to the UE 10 that there is new UL data to be transmitted trigger/indicate UE 10 to perform PHR procedure. The subsequent data arrival may occur before, during or after the first uplink transmission. The UE 10 action of whether and how to perform the PHR procedure may be configured by the base station 20. The base station 20 may command the UE 10 not to perform PHR or cancel the PHR procedure.

At Step 402, UE 10 performs PHR procedure and sends PHR related information to the base station 20. The UE assistance information and/or the BSR may be sent to the base station 20 too, optionally.

At Step 403, after receiving the PHR information from the UE 10, the base station 20 sends TPC command to the UE 10 for the subsequent uplink transmission. The base station 20 may generate the TPC command based on the PHR from the UE 10. The TPC command can be transmitted to the UE 10 with the UL Grant configuration.

At Step 404, the first phase SDT terminated. For the CG-based SDT, it means the UE 10 finishes the first uplink transmission over the configured grant and goes back to RRC_INACTIVE state. For the RA-based SDT, it means the UE 10 finishes the RRC resume procedure of the SDT and goes back to RRC_INACTIVE state.

At Step 405, the UE 10 performs subsequent uplink transmission with the uplink transmission power configured as the TPC command indicated. The TPC command can be used alone to perform the subsequent uplink transmission. The TPC command can also be utilized in the combination with the Grant Configuration. That is to say the UE 10 may perform the subsequent uplink transmission utilize the uplink grant and with the transmission power configured as the TPC command indicated.

Embodiment 3

Referring to FIG. 5 and FIG. 6. FIG. 5 illustrates a flow of a method of controlling power headroom report for small data transmission according to a fourth embodiment of the present disclosure. FIG. 6 illustrates a flow of a method of controlling power headroom report for small data transmission according to a fifth embodiment of the present disclosure. This embodiment focuses on the PHR procedure of the 4-step RA-based SDT (as illustrated in FIG. 5) and 2-step RA-based SDT (as illustrated in FIG. 6) . In the RA-based SDT, the UL data shall be transmitted to the base station 20 as the payload of the Msg3/MsgA. Before, during or after the transmission of Msg3/MsgA, if there is subsequent data arrival, or BSR generated, or data arrival indication indicate that there is new uplink data to be transmitted, the PHR procedure shall be triggered for the UE to send the PHR information to the UE. Optionally, the UE assistance information and/or the subsequent data arrival information (e.g. BSR) may be transmitted to the base station 20 in addition to the PHR. The PHR (may include the BSR and/or UE assistance information) may be transmitted to the base station 20 in the Msg3/MsgA. Or in another way, another uplink transmission may be initiated for the UE to send the PHR information (may include the BSR and/or UE assistance information) to the base station 20.

With PHR and/or BSR information received from the UE 10, the base station 20 shall perform the UL scheduling of the subsequent data transmission by sending the UL scheduling information to the UE 10. Then the UE 10 may perform the subsequent UL transmission with the scheduling information.

The scheduling information may be sent to UE in the Msg4, i.e. RRCResumeRelease message by the base station 20. And the UL Grant configuration, e.g. Configured Grant, Dynamic Grant, etc. may be included in the scheduling information. Then the UE 10 may transmit the subsequent to the base station 20 with the UL Grant.

UE 10 initiates RRC resume procedure and performs the first UL transmission of the SDT procedure. The RRC resume procedure may be the 4-step RA-based SDT or 2-step RA-based SDT. For 4-step RA-based SDT, the UL data may be sent to the base station 20 as the payload of the Msg3. For 2-step RA-based SDT, the UL data may be sent to the base station 20 as the payload of the MsgA. At step 500 or at step 600, before the UL data transmission of the RA-based SDT is transmitted, some preparation work may be done, such as carrier selection (SUL and NUL) , beam selection, etc. An indication may be transmitted to the UE 10 from the base station 20 before, during or after the Msg3/MsgA transmission indicating the UE 10 to perform the PHR or not to perform PHR or to cancel PHR procedure.

At step 501 or step 601, subsequent data arrival/BSR/new data arrival indication indicating to the UE 10 that there is new UL data to be transmitted trigger the UE 10 to perform PHR procedure. The subsequent data arrival may occur before, during or after the transmission of the Msg3/MsgA. The action of the UE 10 as to whether and how to perform the PHR procedure may be configured by the base station 20. The base station 20 may also indicate the UE 10 to not perform PHR or cancel the PHR procedure.

At step 502 or step 602, the UE 10 performs PHR procedure and sends PHR related information to the base station 20. The UE assistance information and/or the BSR may be sent to the base station 20 too, optionally. The PHR and/or BSR and/or UE assistance may be sent to the base station 20 in the Msg3/MsgA, or another uplink transmission may be initiated for the UE 10 to transmit the PHR and/or BSR and/or UE assistance information to the base station 20.

At step 503 or step 603, the base station 20 send RRCResumeRelease message to the UE 10 and the UE 10 goes back to the RRC_INACTIVE state.

Referring to FIG. 7 and FIG. 8. FIG. 7 illustrates a flow of a method of controlling power headroom report for small data transmission according to a sixth embodiment of the present disclosure. FIG. 8 illustrates a flow of a method of controlling power headroom report for small data transmission according to a seventh embodiment of the present disclosure. The UE 10 initiates RRC resume procedure and performs the first UL transmission of the SDT procedure. The RRC resume procedure may be the 4-step RA-based SDT or 2-step RA-based SDT. For 4-step RA-based SDT, the UL data may be sent to the base station 20 as the payload of the Msg3. For 2-step RA-based SDT, the UL data may be sent to the base station 20 as the payload of the MsgA. At step 700 or at step 800, before the UL data transmission of the RA-based SDT is transmitted, some preparation work may be done, such as carrier selection (SUL and NUL) , beam selection, etc. An indication may be transmitted to the UE 10 from the base station 20 before, during or after the Msg3/MsgA transmission indicating the UE 10 to perform the PHR or not to perform PHR or to cancel PHR procedure.

At step 701 or step 801, subsequent data arrival/BSR/new data arrival indication indicating to the UE 10 that there is new UL data to be transmitted trigger the UE 10 to perform PHR procedure. The subsequent data arrival may occur before, during or after the transmission of the Msg3/MsgA. The action of the UE 10 as to whether and how to perform the PHR procedure may be configured by the base station 20. The base station 20 may indicate the UE 10 to not perform PHR or cancel the PHR procedure.

At step 702 or step 802, the UE 10 performs PHR procedure and sends PHR related information to the base station 20. The UE assistance information and/or the BSR may be sent to the base station 20 with the PHR optionally. The PHR and/or BSR and/or UE assistance may be sent to the base station 20 in the Msg3/MsgA, or another uplink transmission may be initiated for the UE 10 to transmit the PHR and/or BSR and/or UE assistance information to the base station 20.

At step 703 or step 803, after receiving the PHR information from the UE 10, the base station 20 shall send the uplink grant configuration to the UE 10 for the subsequent uplink transmission. The base station 20 may generate the uplink grant configuration for the UE 10 based on the PHR from the UE 10. The uplink grant configuration may be transmitted to the UE 10 in the Msg4, i.e. the RRCResumeRelease message. The uplink grant may be Configured Grant (CG) or Dynamic Grant (DG) . The uplink grant may include the radio resource allocation configuration and/or modulation and coding scheme (MCS) configuration for the subsequent uplink transmission. After receiving the RRCResumeRelease message from the base station 20, the first SDT phase is finished and the UE 10 enters RRC_INACTIVE state.

At step 704 or step 804, the UE 10 performs subsequent uplink transmission with the uplink grant configuration received from the base station 20. For the case that the uplink grant is the Configured Grant, the UE 10 perform subsequent uplink transmission with the Configured Grant. For the case that the uplink grant is the Dynamic Grant, the UE 10 perform subsequent uplink transmission with the Dynamic Grant. For the case the uplink grant configuration include the radio resource allocation configuration and/or the MCS configuration, the UE 10 performs the subsequent uplink transmission with the resource allocated and the MCS configuration included in the uplink grant configuration.

Referring to FIG. 9 and FIG. 10. FIG. 9 illustrates a flow of a method of controlling power headroom report for small data transmission according to an eighth embodiment of the present disclosure. FIG. 10 illustrates a flow of a method of controlling power headroom report for small data transmission according to a ninth embodiment of the present disclosure. The UE 10 initiates RRC resume procedure and performs the first UL transmission of the SDT procedure. The RRC resume procedure may be the 4-step RA-based SDT or 2-step RA-based SDT. For 4-step RA-based SDT, the UL data may be sent to the base station 20 as the payload of the Msg3. For 2-step RA-based SDT, the UL data may be sent to the base station 20 as the payload of the MsgA. At step 900 or at step 1000, before the UL data transmission of the RA-based SDT is transmitted, some preparation work may be done, such as carrier selection (SUL and NUL) , beam selection, etc. An indication may be transmitted to the UE 10 from the base station 20 before, during or after the Msg3/MsgA transmission indicating the UE 10 to perform the PHR or not to perform PHR or to cancel PHR procedure.

At step 901 or step 1001, subsequent data arrival/BSR/new data arrival indication indicating to the UE 10 that there is new UL data to be transmitted trigger the UE 10 to perform PHR procedure. The subsequent data arrival may occur before, during or after the transmission of the Msg3/MsgA. The action of the UE 10 as to whether and how to perform the PHR procedure may be configured by the base station 20. The base station 20 may indicate the UE 10 to not perform PHR or cancel the PHR procedure.

At step 902 or step 1002, the UE 10 performs PHR procedure and sends PHR related information to the base station 20. The UE assistance information and/or the BSR may be sent to the base station 20 with the PHR optionally. The PHR and/or BSR and/or UE assistance may be sent to the base station 20 in the Msg3/MsgA, or another uplink transmission may be initiated for the UE 10 to transmit the PHR and/or BSR and/or UE assistance information to the base station 20.

At step 903 or step 1003, after receiving the PHR information from the UE 10, the base station 20 sends the TPC command to the UE 10 for the subsequent uplink transmission. The base station 20 may generate the TPC command based on the PHR received from the UE 10. The TPC command may be transmitted to the UE 10 in the Msg4, i.e. the RRCResumeRelease message. The TPC command may be transmitted to the UE 10 together with the uplink grant configuration. After receiving the RRCResumeRelease message from the base station 20, the first SDT phase is finished and the UE 10 enters RRC_INACTIVE state.

At step 904 or step 1004, The UE 10 performs the subsequent uplink transmission with the uplink transmission power configured as the TPC command indicated. The TPC command can be used for the UE 10 to perform the subsequent uplink transmission. The TPC command can be utilized for the UE 10 in combination with the uplink grant configuration. That is to say that the UE 10 may perform the subsequent uplink transmission utilize the uplink grant and with the transmission power configured as the TPC command indicated.

Embodiment 4

Referring to FIG. 11 and FIG. 12. FIG. 11 illustrates a flow of a method of controlling power headroom report for small data transmission according to a tenth embodiment of the present disclosure. FIG. 12 illustrates a flow of a method of controlling power headroom report for small data transmission according to an eleventh embodiment of the present disclosure. This embodiment focuses on the PHR procedure of the CG-based SDT. In the CG-based SDT, the UL data shall be transmitted using the CG. Before, during or after the uplink transmission, if there is subsequent data arrival, or BSR generated, or data arrival indication indicating that there is new uplink data to be transmitted, the PHR procedure shall be triggered for the UE 10 to send the PHR information to the UE 10. Optionally, the UE assistance information and/or the subsequent data arrival information (e.g. BSR) may be sent to the base station 20 in addition to the PHR. The PHR information (may also include the BSR and/or UE assistance information) may be sent to the base station 20 as part of the payload of the UL transmission. Or in another way, another uplink transmission may be initiated for the UE 10 to send the PHR information (may include the BSR and/or UE assistance information) to the UE 10.

The CG configuration may be sent to the UE 10 by the base station 20 before or during the procedure that the UE 10 enters RRC_INACTIVE state from RRC_CONNECTED state before the SDT procedure, and the UE 10 may obtain the PHR configuration from the base station 20.

The PHR configuration received from the base station 20 may explicitly indicate the UE 10 to or not to perform PHR procedure during the SDT procedure (including the subsequent SDT procedure) . If the PHR configuration indicated the UE 10 to perform PHR, the UE 10 may perform PHR procedure regardless of whether there is subsequent data arrival. Or alternatively, the UE 10 may determine whether to perform PHR procedure based on whether there is subsequent data arrival/BSR, i.e. if there is subsequent data arrival/BSR, then the UE 10 may perform PHR procedure, otherwise the UE 10 may not perform PHR procedure.

In another way, if the PHR configuration indicated the UE 10 not to perform PHR procedure, the UE 10 may not perform PHR procedure or the UE 10 may cancel the PHR procedure if it is performing PHR, regardless whether there is subsequent data arrival/BSR. Or alternatively, the UE 10 may not perform PHR procedure until there is subsequent data to be transmitted.

Whether the UE 10 performs PHR procedure can be determined by any combination of at least one of the indication (s) or trigger (s) , including implicit ways mentioned in the embodiments above or/and explicit ways described in this embodiment, etc.

After receiving the PHR and/or BSR information from the UE 10, the base station 20 shall send the UE 10 with scheduling information for the subsequent transmission. Then the UE 10 may perform uplink transmission with the scheduling information.

The scheduling information may include the UL Grant configuration, e.g. Configured Grant, Dynamic Grant, etc. Then the UE 10 may transmit the subsequent to the base station 20 with the UL Grant. The scheduling information may include the TPC command, then the UE 10 may perform the subsequent SDT with the transmission power configured as the TPC command indicated.

At step 1100, the UE 10 performs CG-based SDT procedure. The procedure includes CG-based SDT preparation and UL transmission. The preparation operation includes that the UE 10 obtains CG configuration from the base station 20 before the UE 10 enters the RRC_INACTIVE state from the RRC_CONNECTED state. The UE 10 may use this CG to perform uplink transmission in the CG-based SDT procedure. In addition to the CG configuration, the base station 20 may send PHR configuration to the UE 10 to indicate the UE 10 to or not to perform PHR during the SDT procedure. The UE 10 performs uplink transmission of the SDT with the CG as the CG configuration indicated.

At step 1101, subsequent data arrival/BSR/new data arrival indication indicates the UE 10 that there is new uplink data to be sent trigger the UE 10 to perform PHR procedure. The subsequent data arrival/BSR may occur before, during or after the uplink transmission of the CG-based SDT. For the case that the PHR configuration obtained in step 1100 indicates the UE 10 to or not to perform PHR, the UE 10 may determine whether to perform PHR according to the PHR configuration regardless of whether there is subsequent data arrived or not.

At step 1102, the UE 10 performs PHR procedure and sends the PHR related information to the base station 20. The UE assistance information and/or BSR may be sent to the base station 20 as well. The PHR and/or BSR and/or UE assistance information may be sent to the base station 20 as part of the payload of the uplink transmission of the CG-based SDT in step 1100, or another uplink transmission may be initiated for the UE 10 to transmit the PHR and/or BSR and/or UE assistance information to the base station 20.

Referring to FIG. 12, at step 1200, the UE 10 performs CG-based SDT procedure. The procedure includes CG-based SDT preparation and UL transmission. The preparation operation includes that the UE 10 obtains CG configuration from the base station 20 before the UE 10 enters the RRC_INACTIVE state from the RRC_CONNECTED state. The UE 10 may use this CG to perform uplink transmission in the CG-based SDT procedure. In addition to the CG configuration, the base station 20 may send PHR configuration to the UE 10 to indicate the UE 10 to or not to perform PHR during the SDT procedure. The UE 10 performs uplink transmission of the SDT with the CG as the CG configuration indicated.

At step 1201, subsequent data arrival/BSR/new data arrival indication indicates the UE 10 that there is new uplink data to be sent triggering the UE 10 to perform PHR procedure. The subsequent data arrival/BSR may occur before, during or after the uplink transmission of the CG-based SDT. For the case that the PHR configuration obtained in step 1100 indicates the UE 10 to or not to perform PHR, the UE 10 may determine whether to perform PHR according to the PHR configuration regardless of whether there is subsequent data arrived or not.

At step 1202, the UE 10 performs PHR procedure and sends the PHR related information to the base station 20. The UE assistance information and/or BSR may be sent to the base station 20 as well. The PHR and/or BSR and/or UE assistance information may be sent to the base station 20 as part of the payload of the uplink transmission of the CG-based SDT in step 1200, or another uplink transmission may be initiated for the UE 10 to transmit the PHR and/or BSR and/or UE assistance information to the base station 20.

At step 1203, after receiving the PHR information from the UE 10, the base station 20 shall send uplink grant configuration to the UE 10 for the subsequent uplink transmission. The base station 20 may generate the uplink grant configuration for the UE 10 based on the PHR received from the UE 10. The uplink grant configuration may be the configured grant or dynamic grant. The uplink grant configuration may include the radio resource allocation, e.g. RBs (Radio Bearers) configuration (e.g., start RB, RB number, etc. ) and/or MCS configuration for the subsequent uplink transmission.

At step 1204, the UE 10 performs the subsequent uplink transmission utilizing the uplink grant information received from the base station 20. The UE 10 performs the subsequent uplink transmission with the uplink grant received from the base station 20. For the case that the resource allocation configuration and/or MCS configuration is included in the uplink grant configuration, the UE 10 performs the subsequent uplink grant with the resource and/or MCS configured as the uplink grant configuration indicated.

Referring to FIG. 13 illustrating a flow of a method of controlling power headroom report for small data transmission according to a twelfth embodiment of the present disclosure, at step 1300, the UE 10 performs CG-based SDT procedure. The procedure includes CG-based SDT preparation and UL transmission. The preparation operation includes that the UE 10 obtains CG configuration from the base station 20 before the UE 10 enters the RRC_INACTIVE state from the RRC_CONNECTED state. The UE 10 may use this CG to perform uplink transmission in the CG-based SDT procedure. In addition to the CG configuration, the base station 20 may send PHR configuration to the UE 10 to indicate the UE 10 to or not to perform PHR during the SDT procedure. The UE 10 performs uplink transmission of the SDT with the CG as the CG configuration indicated.

At step 1301, subsequent data arrival/BSR/new data arrival indication indicates the UE 10 that there is new uplink data to be sent triggering the UE 10 to perform PHR procedure. The subsequent data arrival/BSR may occur before, during or after the uplink transmission of the CG-based SDT. For the case that the PHR configuration obtained in step 1100 indicates the UE 10 to or not to perform PHR, the UE 10 may determine whether to perform PHR according to the PHR configuration regardless of whether there is subsequent data arrived or not.

At step 1302, the UE 10 performs PHR procedure and sends the PHR related information to the base station 20. The UE assistance information and/or BSR may be sent to the base station 20 as well. The PHR and/or BSR and/or UE assistance information may be sent to the base station 20 as part of the payload of the uplink transmission of the CG-based SDT in step 1200, or another uplink transmission may be initiated for the UE 10 to transmit the PHR and/or BSR and/or UE assistance information to the base station 20.

At step 1303, after receiving the PHR information from the UE 10, the base station 20 shall send TPC command to the UE 10 for the subsequent uplink transmission. The base station 20 may generate the TPC command based on the PHR received from the UE 10. Optionally, the TPC command can be transmitted to the UE 10 together with the UL Grant configuration.

At step 1304, the UE 10 performs subsequent uplink transmission with the uplink transmission power configured as the TPC command indicated. The TPC command can be used for the UE 10 to perform transmission power control while performing the subsequent uplink transmission. The TPC command can be utilized in combination with the uplink grant configuration mentioned in solution 2 for the UE 10 to perform the subsequent uplink transmission. The UE 10 may perform the subsequent uplink transmission with the resources configured as the uplink grant configuration indicated and transmission power set as the TPC command configured. Embodiment 5

Referring to FIG. 14 illustrating a flow of a method of controlling power headroom report for small data transmission according to a thirteenth embodiment of the present disclosure, this embodiment focuses on the case that the subsequent data shall be sent to the base station 20 with the UE 10 entering RRC_CONNECTED state, i.e. the UE 10 may perform RRC resume procedure or RRC connection (re) establishment procedure and transit into RRC_CONNECTED state, then perform uplink transmission and send the subsequent data to the base station 20, namely SDT switch to non-SDT.

During or after the first phase (i.e. the first UL small data transmission) of the small data transmission, if there is subsequent data arrival, or BSR generated, or data arrival indication indicate that there is new uplink data to be sent to the base station 20, the PHR shall be triggered for the UE 10 to report the PHR related information to the base station 20. Optionally, the UE assistance information and/or the subsequent data arrival information (e.g. BSR) may be sent to the base station 20 together with the PHR. So that the base station 20 shall perform the UL scheduling of the subsequent small data transmission for the UE 10.

If the subsequent data meet the criterion for the UE 10 to switch to non-SDT uplink transmission, i.e. enters RRC_CONNECTED state to perform the uplink transmission of the subsequent data, the UE 10 may perform RRC Resume or RRC (re) establishment procedure to enter RRC_CONNECTED state and then sent the subsequent data to the base station 20 as the scheduling configuration received from the base station 20 indicated. Optionally, the scheduling configuration received from the base station 20 might be the TPC command.

At step 1400, the UE 10 performs CG-based SDT procedure. The procedure includes CG-based SDT preparation and UL transmission. The preparation operation includes that the UE 10 obtains CG configuration from the base station 20 before the UE 10 enters the RRC_INACTIVE state from the RRC_CONNECTED state. The UE 10 may use this CG to perform uplink transmission in the CG-based SDT procedure. In addition to the CG configuration, the base station 20 may send PHR configuration to the UE 10 to indicate the UE 10 to or not to perform PHR during the SDT procedure. The UE 10 performs uplink transmission of the SDT with the CG as the CG configuration indicated.

At step 1401, subsequent data arrival/BSR/new data arrival indication indicates the UE 10 that there is new uplink data to be sent triggering the UE 10 to perform PHR procedure. The subsequent data arrival/BSR may occur before, during or after the uplink transmission of the CG-based SDT. For the case that the PHR configuration obtained in step 1100 indicates the UE 10 to or not to perform PHR, the UE 10 may determine whether to perform PHR according to the PHR configuration regardless of whether there is subsequent data arrived or not.

At step 1402, the UE 10 performs PHR procedure and sends the PHR related information to the base station 20. The UE assistance information and/or BSR may be sent to the base station 20 as well. The PHR and/or BSR and/or UE assistance information may be sent to the base station 20 as part of the payload of the uplink transmission of the CG-based SDT in step 1200, or another uplink transmission may be initiated for the UE 10 to transmit the PHR and/or BSR and/or UE assistance information to the base station 20.

At step 1403, after receiving the PHR information from the UE 10, the base station 20 shall send uplink grant configuration to the UE 10 for the subsequent uplink transmission. The base station 20 may generate the uplink grant configuration for the UE 10 based on the PHR received from the UE 10. The uplink grant configuration may be the configured grant or dynamic grant. The uplink grant configuration may include the radio resource allocation, e.g. RB (Radio Bearer) configuration (e.g. start RB index, RB number, etc. ) and/or MCS configuration for the subsequent uplink transmission. In addition, after receiving the PHR information from the UE 10, the base station 20 shall send TPC command to the UE 10 for the subsequent uplink transmission. The base station 20 may generate the TPC command based on the PHR received from the UE 10. Optionally, the TPC command can be transmitted to the UE 10 together with the UL Grant configuration.

At step 1404, the base station 20 send the scheduling configuration to the UE 10, then the UE 10 performs RRC Resume or RRC (re) establishment procedure, i.e. switch to non-SDT procedure and initiate uplink transmission with the configuration indicated in the scheduling configuration. The scheduling configuration may be TPC command, and the UE 10 performs the subsequent uplink transmission with the transmission power configured as the TPC command indicated. In another way, the scheduling configuration may be uplink grant or/and the RACH resource (including preambles and/or RACH occasion) used to perform RRC resume or RRC (re) establishment procedure.

Embodiment 6

The UE 10 may not perform PHR during the SDT procedure as default configuration, and it shall not perform PHR during the SDT procedure and/or subsequent SDT procedure no matter whether there is subsequent data to be transmitted. Or in another case, the UE 10 may perform PHR during the SDT procedure as default configuration, and it would perform PHR during SDT and/or subsequent SDT procedure regardless whether there is subsequent data to be transmitted.

The base station 20 may send PHR configuration to the UE 10 indicate the UE 10 to perform PHR based on the subsequent data arrival and/or BSR. If there is subsequent data arrival or BSR for the subsequent uplink transmission generated, then the UE 10 may be triggered to perform PHR procedure. Otherwise, if there is no subsequent data arrival or BSR generated, then the UE 10 may not perform the PHR procedure.

In another hand, the UE 10 may be configured to determine whether to perform PHR based on the subsequent data arrival, if the subsequent data arrival meet the configured criterion, then the UE 10 may perform PHR. Otherwise, the UE 10 may not perform PHR procedure.

In a third way, if there is subsequent data arrival, the UE 10 may send the BSR to the base station 20, then the base station 20 shall send PHR configuration to the UE 10, then the UE 10 performs the PHR procedure according to the PHR configuration. Otherwise, it the base station 20 send indication to the UE 10 not to perform PHR, or if the UE 10 did not receive PHR configuration from the base station 20, then the UE 10 may not perform the PHR procedure.

The base station 20 may send PHR configuration to the UE 10 or update the PHR configuration of the UE 10 indicate the UE 10 to perform PHR no matter whether there is subsequent data arrival. And the base station 20 may also update the PHR configuration of the UE 10 or send PHR cancellation indication to the UE 10 to indicate the UE 10 not to perform PHR, or to cancel the ongoing PHR procedure regardless whether there is subsequent data arrival.

At last, the path loss or path loss change may be configured to associate with the scheduling configuration for the UE. The UE 10 may measure the path loss or path loss change and select the associated value of the scheduling configuration to perform the SDT and/or subsequent SDT procedure. The scheduling configuration may include the uplink grant (CG/DG) and/or the radio resource (e.g. RB) and/or the TPC command, etc.

In summary, according to an embodiment of the present disclosure, a method for controlling power headroom report for small data transmission (SDT) operable in a user equipment (UE) , comprising: triggering a power headroom report (PHR) upon detecting subsequent data transmitting information; transmitting the PHR to a base station.

According to an embodiment of the present disclosure, the method further comprises: receiving uplink (UL) scheduling information from the base station; and transmitting subsequent data to the base station.

According to an embodiment of the present disclosure, the receiving UL scheduling information from the base station comprises: receiving UL scheduling information determined based on the PHR from the base station; and the transmitting subsequent data to the base station comprises: transmitting subsequent data to the base station based on the UL scheduling information.

According to an embodiment of the present disclosure, the data-transmitting information comprises subsequent data arrival, or a Buffer Status Report (BSR) , or a data arrival indication indicating that there is new uplink data to be transmitted.

According to an embodiment of the present disclosure, the transmitting the PHR to the base station comprises: transmitting the PHR along with a UE assistance information and/or a Buffer Status Report (BSR) .

According to an embodiment of the present disclosure, the UL scheduling information comprises a Radio Resource Control (RRC) Resume Release message.

According to an embodiment of the present disclosure, before the triggering the power headroom report, the method further comprises: performing carrier selection and/or beam selection; and initiating Random Access-based (RA-based) SDT procedure.

According to an embodiment of the present disclosure, after the receiving uplink (UL) scheduling information, the method further comprises: entering RRC_INACTIVE state in response to the RRC Resume Release message.

According to an embodiment of the present disclosure, the UL scheduling information comprises a Transmission Power Control (TPC) command.

According to an embodiment of the present disclosure, after the receiving uplink (UL) scheduling information, the transmitting subsequent data based on the UL scheduling information comprises: transmitting subsequent data with transmission power configured as the TPC command indicated.

According to an embodiment of the present disclosure, the UL scheduling information comprises a UL Grant configuration.

According to an embodiment of the present disclosure, the UL Grant configuration comprises a Configured Grant (CG) information or Dynamic Grant (DG) information.

According to an embodiment of the present disclosure, after the receiving uplink (UL) scheduling information, the transmitting subsequent data based on the UL scheduling information comprises: transmitting subsequent data with Configured Grant or Dynamic Grant.

According to an embodiment of the present disclosure, the UL Grant configuration comprises a radio resource allocation configuration and/or Modulation and Code scheme (MCS) configuration for the subsequent uplink transmission.

According to an embodiment of the present disclosure, after the receiving uplink (UL) scheduling information, the transmitting subsequent data based on the UL scheduling information comprises: transmitting subsequent data with a radio bearer (RB) as the radio resource allocation configuration indicated and/or MCS configuration.

According to an embodiment of the present disclosure, before the triggering the power headroom report, the method further comprising: receiving a Configured Grant configuration sent by the base station to enter an RRC_INACTIVE state from RRC_CONNECTED state.

According to an embodiment of the present disclosure, the method further comprises: receiving a scheduling configuration from the base station to perform RRC Resume or RRC establishment procedure to enter RRC_CONNECTED state; and transmitting subsequent data based on the scheduling configuration.

According to an embodiment of the present disclosure, the method further comprises: receiving a PHR activating command from the base station to activate a PHR procedure to trigger the PHR upon detecting subsequent data transmitting information.

According to an embodiment of the present disclosure, the method further comprises: stopping triggering the power headroom report upon receiving a PHR terminating command from the base station.

According to an embodiment of the present disclosure, a user equipment (UE) comprising: a memory; a transceiver; and a processor coupled to the memory and the transceiver. The processor is configured to execute the operations as provided in the above method.

According to an embodiment of the present disclosure, a chip comprising: a processor, configured to call and run a computer program stored in a memory, to cause a device in which the chip is installed to execute the operation as provided in the above method.

According to an embodiment of the present disclosure, a computer readable storage medium, in which a computer program is stored, wherein the computer program causes a computer to execute the operations as provided in the above method.

According to an embodiment of the present disclosure, a method for controlling power headroom report for small data transmission operable in a base station comprising: receiving a power headroom report (PHR) that is triggered by a user equipment (UE) in response to a detection of subsequent data transmitting information.

According to an embodiment of the present disclosure, the method further comprises: transmitting uplink (UL) scheduling information to the UE; and receiving subsequent data sent based on the UL scheduling information.

According to an embodiment of the present disclosure, the UL scheduling information is determined based on the PHR.

According to an embodiment of the present disclosure, the receiving the PHR comprises:

receiving the PHR along with a UE assistance information and/or a Buffer Status Report (BSR) .

According to an embodiment of the present disclosure, before the receiving the power headroom report, the method further comprising: performing carrier selection and/or beam selection; and initiating Random Access-based (RA-based) SDT procedure.

According to an embodiment of the present disclosure, after the transmitting uplink (UL) scheduling information, the method further comprises: entering RRC_INACTIVE state in response to the RRC Resume Release message.

According to an embodiment of the present disclosure, after the transmitting uplink (UL) scheduling information, the receiving subsequent data based on the UL scheduling information comprises: receiving subsequent data with transmission power configured as the TPC command indicated.

According to an embodiment of the present disclosure, after the transmitting uplink (UL) scheduling information, the receiving subsequent data based on the UL scheduling information comprises: receiving subsequent data with Configured Grant or Dynamic Grant.

According to an embodiment of the present disclosure, after the transmitting uplink (UL) scheduling information, the receiving subsequent data based on the UL scheduling information comprises: receiving subsequent data with a radio bearer (RB) as the radio resource allocation configuration indicated and/or MCS configuration.

According to an embodiment of the present disclosure, before the receiving the PHR, the method further comprises: transmitting a Configured Grant configuration to the UE so that the UE enters an RRC_INACTIVE state from RRC_CONNECTED state.

According to an embodiment of the present disclosure, the method further comprises: transmitting a scheduling configuration to the UE so that the UE performs RRC Resume or RRC establishment procedure to enter RRC_CONNECTED state; and receiving subsequent data based on the scheduling configuration.

According to an embodiment of the present disclosure, the method further comprises: transmitting a PHR activating command to the UE, so that the UE activates a PHR procedure to trigger the PHR upon detecting subsequent data transmitting information.

According to an embodiment of the present disclosure, the method further comprises: transmitting a PHR terminating command to the UE, so that the UE stops triggering the power headroom report upon receiving the PHR terminating command.

According to an embodiment of the present disclosure, a base station comprising: a memory; a transceiver; and a processor coupled to the memory and the transceiver. The processor is configured to execute the operations as provided in the above method.

FIG. 15 is a block diagram of an example system 700 for wireless communication according to an embodiment of the present disclosure. Embodiments described herein may be implemented into the system using any suitably configured hardware and/or software. FIG. 15 illustrates the system 700 including a radio frequency (RF) circuitry 710, a baseband circuitry 720, a processing unit 730, a memory/storage 740, a display 750, a camera 760, a sensor 770, and an input/output (I/O) interface 780, coupled with each other as illustrated.

The processing unit 730 may include a circuitry, such as, but not limited to, one or more single-core or multi-core processors. The processors may include any combinations of general-purpose processors and dedicated processors, such as graphics processors and application processors. The processors may be coupled with the memory/storage and configured to execute instructions stored in the memory/storage to enable various applications and/or operating systems running on the system. The RF circuitry 710, baseband circuitry 720, processing unit 730, memory/storage 740, display 750, camera 760, sensor 770, and I/O interface 780 are well-known elements in the system 700 such as, but not limited to, a laptop computing device, a tablet computing device, a netbook, an ultrabook, a smartphone, etc. In addition, the instructions as a software product can be stored in a readable storage medium in a computer. The software product in the computer is stored in a storage medium, including a plurality of commands for a computational device (such as a personal computer, a server, or a network device) to run all or some of the steps disclosed by the embodiments of the present disclosure. The storage medium includes a USB disk, a mobile hard disk, a read-only memory (ROM) , a random access memory (RAM) , a floppy disk, or other kinds of media capable of storing program codes.

The embodiment of the present disclosure is a combination of techniques/processes that can be adopted in 3GPP specification to create an end product.

Embodiments of the disclosure are provided to a method for controlling power headroom report for small data transmission (SDT) operable in a user equipment (UE) includes: triggering a power headroom report (PHR) upon detecting subsequent data transmitting information; transmitting the PHR to a base station; receiving uplink (UL) scheduling information from the base station; and transmitting subsequent data based on the UL scheduling information. The present disclosure improves not only network performance and efficiency but also the UE battery performance.

While the present disclosure has been described in connection with what is considered the most practical and preferred embodiments, it is understood that the present disclosure is not limited to the disclosed embodiments but is intended to cover various arrangements made without departing from the scope of the broadest interpretation of the appended claims.

Claims

A method for controlling power headroom report for small data transmission (SDT) operable in a user equipment (UE) , comprising:

triggering a power headroom report (PHR) upon detecting subsequent data transmitting information; and

transmitting the PHR to a base station.
The method of claim 1, further comprising:

receiving uplink (UL) scheduling information from the base station; and

transmitting subsequent data to the base station.
The method of claim 2, wherein the receiving UL scheduling information from the base station comprises:

receiving UL scheduling information determined based on the PHR from the base station; and

the transmitting subsequent data to the base station comprises:

transmitting subsequent data to the base station based on the UL scheduling information.
The method of claim 1, wherein the data-transmitting information comprises subsequent data arrival, or a Buffer Status Report (BSR) , or a data arrival indication indicating that there is new uplink data to be transmitted.
The method of claim 1, wherein the transmitting the PHR to the base station comprises: transmitting the PHR along with a UE assistance information and/or a Buffer Status Report (BSR) .
The method of claim 2, wherein the UL scheduling information comprises a Radio Resource Control (RRC) Resume Release message.
The method of claim 6, wherein before the triggering the power headroom report, the method further comprising:

performing carrier selection and/or beam selection; and

initiating Random Access-based (RA-based) SDT procedure.
The method of claim 7, wherein after the receiving uplink (UL) scheduling information, the method further comprises:

entering RRC_INACTIVE state in response to the RRC Resume Release message.
The method of claim 2, wherein the UL scheduling information comprises a Transmission Power Control (TPC) command.
The method of claim 9, wherein after the receiving uplink (UL) scheduling information, the transmitting subsequent data based on the UL scheduling information comprises:

transmitting subsequent data with transmission power configured as the TPC command indicated.
The method of claim 2, wherein the UL scheduling information comprises a UL Grant configuration.
The method of claim 11, wherein the UL Grant configuration comprises a Configured Grant (CG) information or Dynamic Grant (DG) information.
The method of claim 12, wherein after the receiving uplink (UL) scheduling information, the transmitting subsequent data based on the UL scheduling information comprises:

transmitting subsequent data with Configured Grant or Dynamic Grant.
The method of claim 11, wherein the UL Grant configuration comprises a radio resource allocation configuration and/or Modulation and Code scheme (MCS) configuration for the subsequent uplink transmission.
The method of claim 14, wherein after the receiving uplink (UL) scheduling information, the transmitting subsequent data based on the UL scheduling information comprises:

transmitting subsequent data with a radio bearer (RB) as the radio resource allocation configuration indicated and/or MCS configuration.
The method of claim 1, wherein before the triggering the power headroom report, the method further comprising:

receiving a Configured Grant configuration sent by the base station to enter an RRC_INACTIVE state from RRC_CONNECTED state.
The method of claim 1, further comprising:

receiving a scheduling configuration from the base station to perform RRC Resume or RRC establishment procedure to enter RRC_CONNECTED state; and

transmitting subsequent data based on the scheduling configuration.
The method of claim 1, further comprising:

receiving a PHR activating command from the base station to activate a PHR procedure to trigger the PHR upon detecting subsequent data transmitting information.
The method of claim 1, further comprising:

stopping triggering the power headroom report upon receiving a PHR terminating command from the base station.
A user equipment (UE) , comprising:

a memory;

a transceiver; and

a processor coupled to the memory and the transceiver;

wherein the processor is configured to execute the method of any one of claims 1-19.
A method for controlling power headroom report for small data transmission operable in a base station, comprising:

receiving a power headroom report (PHR) that is triggered by a user equipment (UE) in response to a detection of subsequent data transmitting information.
The method of claim 21, further comprising:

transmitting uplink (UL) scheduling information to the UE; and

receiving subsequent data sent based on the UL scheduling information.
The method of claim 22, wherein the UL scheduling information is determined based on the PHR.
The method of claim 21, wherein the data-transmitting information comprises subsequent data arrival, or a Buffer Status Report (BSR) , or a data arrival indication indicating that there is new uplink data to be transmitted.
The method of claim 21, wherein the receiving the PHR comprises:

receiving the PHR along with a UE assistance information and/or a Buffer Status Report (BSR) .
The method of claim 22, wherein the UL scheduling information comprises a Radio Resource Control (RRC) Resume Release message.
The method of claim 26, wherein before the receiving the power headroom report, the method further comprising:

performing carrier selection and/or beam selection; and

initiating Random Access-based (RA-based) SDT procedure.
The method of claim 27, wherein after the transmitting uplink (UL) scheduling information, the method further comprises:

entering RRC_INACTIVE state in response to the RRC Resume Release message.
The method of claim 22, wherein the UL scheduling information comprises a Transmission Power Control (TPC) command.
The method of claim 29, wherein after the transmitting uplink (UL) scheduling information, the receiving subsequent data based on the UL scheduling information comprises:

receiving subsequent data with transmission power configured as the TPC command indicated.
The method of claim 22, wherein the UL scheduling information comprises a UL Grant configuration.
The method of claim 31, wherein the UL Grant configuration comprises a Configured Grant (CG) information or Dynamic Grant (DG) information.
The method of claim 32, wherein after the transmitting uplink (UL) scheduling information, the receiving subsequent data based on the UL scheduling information comprises:

receiving subsequent data with Configured Grant or Dynamic Grant.
The method of claim 31, wherein the UL Grant configuration comprises a radio resource allocation configuration and/or Modulation and Code scheme (MCS) configuration for the subsequent uplink transmission.
The method of claim 34, wherein after the transmitting uplink (UL) scheduling information, the receiving subsequent data based on the UL scheduling information comprises:

receiving subsequent data with a radio bearer (RB) as the radio resource allocation configuration indicated and/or MCS configuration.
The method of claim 33, wherein before the receiving the PHR, the method further comprising:

transmitting a Configured Grant configuration to the UE so that the UE enters an RRC_INACTIVE state from RRC_CONNECTED state.
The method of claim 33, further comprising:

transmitting a scheduling configuration to the UE so that the UE performs RRC Resume or RRC establishment procedure to enter RRC_CONNECTED state; and

receiving subsequent data based on the scheduling configuration.
The method of claim 33, further comprising:

transmitting a PHR activating command to the UE, so that the UE activates a PHR procedure to trigger the PHR upon detecting subsequent data transmitting information.
The method of claim 33, further comprising:

transmitting a PHR terminating command to the UE, so that the UE stops triggering the power headroom report upon receiving the PHR terminating command.
A base station, comprising:

a memory;

a transceiver; and

a processor coupled to the memory and the transceiver;

wherein the processor is configured to execute the method of any one of claim 21-39.
A chip, comprising:

a processor, configured to call and run a computer program stored in a memory, to cause a device in which the chip is installed to execute the method of any one of claims 21-39.
A computer readable storage medium, in which a computer program is stored, wherein the computer program causes a computer to execute the method of any one of claims 21-39.
A computer program product, comprising a computer program, wherein the computer program causes a computer to execute the method of any one of claims 21-39.
A chip, comprising:

a processor, configured to call and run a computer program stored in a memory, to cause a device in which the chip is installed to execute the method of any one of claims 1-19.
A computer readable storage medium, in which a computer program is stored, wherein the computer program causes a computer to execute the method of any one of claims 1-19.
A computer program product, comprising a computer program, wherein the computer program causes a computer to execute the method of any one of claims 1-19.