METHOD AND APPARATUS FOR SMALL DATA TRANSMISSION

Embodiments of the present application relate to a method and an apparatus for or small data transmission of a user equipment (UE) in an RRC_IDLE state or an RRC_INACTIVE state. According to an embodiment of the present application, a method can include: a method may include maintaining a priority variable for each logical channel of at least one logical channel; determining a value of the priority variable for each logical channel after performing a first logical channel prioritization (LCP) procedure; receiving a message indicating a MAC reset; and after receiving the message, in a second LCP procedure subsequent to the first LCP procedure, using the value as an initial value of the priority variable for each logical channel of the at least one logical channel. Embodiments of the present application can satisfy the QoS requirement and fairness for the traffics transmitted in the logical channels in NR systems.

TECHNICAL FIELD

Embodiments of the present application generally relate to wireless communication technology, especially to a method and an apparatus for small data transmission of a user equipment (UE) in an RRC_IDLE state or an RRC_INACTIVE state.

BACKGROUND

In long term evolution (LTE), in the case that a UE wants to transmit data, it may trigger an early data transmission (EDT) procedure. The EDT procedure may include an EDT procedure for control plane (CP) cellular internet of things (CIoT) evolved packet system (EPS) optimizations and an EDT procedure for user plane (UP) CIoT EPS optimizations. In the EDT procedure for CP CIoT EPS optimizations, the data may be transmitted through a radio resource control (RRC) early data request message. In the EDT procedure for UP CIoT EPS optimizations, the data may be transmitted through an RRC connection resume request message.

New radio (NR) supports an RRC_INACTIVE state. In the case that the UE wants to transmit data in the RRC_INACTIVE state, a work item in the NR states that the data may be transmitted through a random access channel (RACH)-based scheme (e.g., 2-step RACH scheme or 4-step RACH scheme) via the pre-configured physical uplink share channel (PUSCH) resources.

All of the above schemes for transmitting data in the RRC_IDLE state or in the RRC_INACTIVE state may involve a medium access control (MAC) reset operation after transmitting the data. However, the MAC reset operation may affect the fairness for the traffics in some logical channels, for example the logical channels with low priorities. In addition, for the data transmission using an EDT procedure for CP CIoT EPS optimizations, how to manage the quality of service (QoS) is another issue.

Therefore, the industry desires an improved technology for small data transmission, so as to satisfy the QoS requirement and fairness for the traffics transmitted in the logical channels in NR systems.

SUMMARY OF THE APPLICATION

Some embodiments of the present application at least provide a technical solution for small data transmission of a UE.

According to some embodiments of the present application, a method may include: maintaining a priority variable for each logical channel of at least one logical channel; determining a value of the priority variable for each logical channel after performing a first logical channel prioritization (LCP) procedure; receiving a message indicating a MAC reset; and after receiving the message, in a second LCP procedure subsequent to the first LCP procedure, using the value as an initial value of the priority variable for each logical channel of the at least one logical channel.

In an embodiment the present application, the message indicating the MAC reset may be one of: an RRC release message including a suspend configuration information element (IE); an RRC early data complete message; and a MAC reset message following small data transmission.

In another embodiment the present application, the at least one logical channel may be used for a small data transmission, and wherein the at least one logical channel may be determined based on configuration information from a base station (BS) and/or a logical channel selection procedure for an uplink (UL) grant.

Some embodiments of the present application also provide an apparatus, include: at least one non-transitory computer-readable medium having computer executable instructions stored therein, at least one receiver; at least one transmitter; and at least one processor coupled to the at least one non-transitory computer-readable medium, the at least one receiver and the at least one transmitter. The computer executable instructions are programmed to implement any method as stated above with the at least one receiver, the at least one transmitter and the at least one processor.

Embodiments of the present application provide a technical solution for small data transmission of a UE, e.g., a UE is not in the RRC_CONNECTED state. For example, the UE may be in the RRC_IDLE state or the RRC_INACTIVE state. Accordingly, embodiments of the present application can satisfy the QoS requirement and fairness for the traffics transmitted in the logical channels in NR systems.

DETAILED DESCRIPTION

The detailed description of the appended drawings is intended as a description of preferred embodiments of the present application, and is not intended to represent the only form in which the present application may be practiced. It should be understood that the same or equivalent functions may be accomplished by different embodiments that are intended to be encompassed within the spirit and scope of the present application.

Reference will now be made in detail to some embodiments of the present application, examples of which are illustrated in the accompanying drawings.

FIG.1is a schematic diagram illustrating an exemplary wireless communication system100according to an embodiment of the present application.

As shown inFIG.1, the wireless communication system100can include at least one base station (BS)101and at least one UE103. Although a specific number of BSs101and UEs103, e.g., only one BS101and one UE103are depicted inFIG.1, one skilled in the art will recognize that any number of the BSs101and UEs103may be included in the wireless communication system100.

The BS101may be distributed over a geographic region, and generally be a part of a radio access network that may include one or more controllers communicably coupled to one or more corresponding BSs. In some embodiments of the present application, each BS may also be referred to as an access point, an access terminal, a base, a macro cell, a Node-B, an evolved Node B (eNB), a gNB, a Home Node-B, a relay node, a device, or described using other terminology used in the art.

The UE103may be a legacy UE (or regular UE) compatible with existing technology, or a normal NR UE. For example, the UE103may be computing devices, such as desktop computers, laptop computers, personal digital assistants (PDAs), tablet computers, smart televisions (e.g., televisions connected to the Internet), set-top boxes, game consoles, security systems (including security cameras), vehicle on-board computers, network devices (e.g., routers, switches, and modems), or the like. According to an embodiment of the present application, the UE103may be a portable wireless communication device, a smart phone, a cellular telephone, a flip phone, a device having a subscriber identity module, a personal computer, a selective call receiver, or any other device that is capable of sending and receiving communication signals on a wireless network. In some embodiments of the present application, the UE103may be a wearable device, such as a smart watch, a fitness band, an optical head-mounted display, or the like. Moreover, the UE103may be referred to as a subscriber unit, a mobile, a mobile station, a user, a terminal, a mobile terminal, a wireless terminal, a fixed terminal, a subscriber station, a user terminal, or a device, or described using other terminology used in the art.

The UE103may be a capability reduced UE, for example, a narrow band internet of things (NB-IoT) UE or an enhance machine type communication (eMTC) UE. The capability reduced UE may be an industrial wireless sensor, a video surveillance, a wearable device, or another device with the characteristics of the capability reduced UE. Compared with a legacy UE, the capability reduced may have a smaller bandwidth to enable several Kbps to several Mbps throughput; and achieve a lower power consumption to enable a longer UE battery life, cost reduction, flexible latency requirement, flexible UE processing time, and flexible UE processing capability, etc.

In long term evolution (LTE), in the case that a UE wants to transmit uplink data, it may trigger an EDT procedure.

According to some embodiments of the present application, the EDT procedure may include an EDT procedure for CP CIoT EPS optimizations. In this procedure, the uplink data may be included in a non-access stratum (NAS) message, the UE may transmit an RRC early data request message including the NAS message to the BS. In response to the RRC early data request message, the BS may transmit an RRC early data complete message. After receiving the RRC early data complete message, the UE may reset MAC and release the MAC configuration. In an embodiment of the present application, the uplink (UL) grant for transmitting the uplink data may be indicated in a random access response message. In an embodiment of the present application, the UL grant for transmitting the uplink data may be the preconfigured uplink resources (PURs).

According to some other embodiments of the present application, the EDT procedure may include an EDT procedure for UP CIoT EPS optimizations. In this procedure, the UE may transmit RRC connection resume request message including the uplink data to the BS. In response to the RRC connection resume request message, the BS may transmit an RRC connection release message including a suspend configuration IE to the UE to keep the UE in the RRC_IDLE state. After receiving the RRC connection release message, the UE may reset MAC. In an embodiment of the present application, the uplink (UL) grant for transmitting the uplink data may be indicated in a random access response message. In an embodiment of the present application, the UL grant for transmitting the uplink data may be the preconfigured uplink resources (PURs).

NR supports an RRC_INACTIVE state. Until Rel-16, the RRC_INACTIVE state doesn't support data transmission. Hence, in the case that the UE in the RRC_INACTIVE state has data to be transmitted, it has to resume the connection (i.e. move to the RRC_CONNECTED state) for any downlink and uplink data transmission. The RRC Connection setup and subsequently release to the RRC_INACTIVE state happen for each data transmission, which results in unnecessary power consumption and signaling overhead. To enable the data transmission in the RRC_INACTIVE state, a work item in the NR states that small data transmission in the RRC_INACTIVE state may be implemented through a random access channel (RACH)-based scheme (e.g., 2-step RACH scheme or 4-step RACH scheme as specified in 3GPP standard documents), without changing the RRC state of the UE to the he RRC_CONNECTED state. For example, the small data may be transmitted using MSGA in 2-step RACH scheme or MSG3 in 4-step RACH scheme. In these schemes, the small data may be transmitted via the pre-configured PUSCH resources (e.g. reusing the configured grant type 1 as specified in 3GPP standard documents). After transmitting the small data, the UE may receive a MAC reset message. If a reset of the MAC entity is requested by upper layers of the UE, the MAC entity may initialize a priority variable (e.g., Bj as specified in 3GPP standard documents) for each logical channel to zero.

The small data may include small and infrequent data traffic. Specific examples of small and infrequent data traffic include the following use cases: 1) smartphone applications; and 2) non-smartphone applications. The smartphone applications may include traffic from instant messaging services (whatsapp, QQ, wechat, etc.); heart-beat/keep-alive traffic from instant messaging (IM)/email clients and other apps; and push notifications from various applications. The non-smartphone applications may include traffic from wearables (e.g., periodic positioning information, etc.), sensors (e.g., industrial wireless sensor networks transmitting temperature, pressure readings periodically or in an event triggered manner, etc), and smart meters and smart meter networks sending periodic meter readings. Persons skilled in the art can understand that the above use cases are only for illustrative purposes, according to some other embodiments, the same data may include the data in other uses cases with same amount and infrequent transmission.

When performing an uplink data transmission, a logical channel prioritization (LCP) procedure may be applied. In the LCP procedure, the RRC controls the scheduling of uplink data by signaling for each logical channel per MAC entity: priority where an increasing priority value indicates a lower priority level; the prioritized bit rate (PBR); and the bucket size duration (BSD). The UE may maintain a priority variable (e.g., Bj) for each logical channel j. The MAC entity of the UE may initialize Bj of the logical channel to zero when the logical channel is established. For each logical channel j, the MAC entity of the UE may increment Bj by the product PBR×T before every instance of the LCP procedure, wherein T is the time elapsed since Bj was last incremented; if the increment would cause the value of Bj to exceed the bucket size (i.e. PBR×BSD), the UE may set Bj to the bucket size. Logical channels with Bj>0 are allocated resources in a decreasing priority order. After the LCP procedure, the UE may decrement Bj by the total size of MAC service data units (SDUs) served to logical channel j in the LCP procedure.

For example,FIG.2illustrates a LCP procedure in NR according to some embodiments of the present application. Referring toFIG.2, assuming that a UE has two logical channels, for example, LCH1and LCH2. The priority of LCH1is higher than LCH2. The UE may maintain a priority variable (e.g., Bj) for each logical channel j. For example, the UE may maintain a priority variable B1for the LCH1and maintain a priority variable B2for the LCH2. The bucket size of LCH1is PBR1×BSD1. The bucket size of LCH2is PBR2×BSD2.

At time t0, the MAC entity of the UE may initialize both B1and B2to zero. After that, the MAC entity of the UE may increment Bj by the product of PBR and T before every instance of the LCP procedure, wherein T is the time elapsed since Bj was last incremented. At a time period TP1, a UL grant1may be available for the UE to transmit uplink user data, and thus the UE may allocate the UL grant to the data in the logical channels with Bj>0 in a decreasing priority order.

As shown inFIG.2, assuming that from time t0to the time when the UL grant1appears, the total time elapsed is N×T, then B1of LCH1may be PBR1×N×T and B2of LCH2may be PBR2×N×T. Since the priority of LCH1is higher than LCH2, the data in the LCH1should be allocated with the resource of the UL granted firstly. As shown inFIG.2, not all the data in the LCH1can be transmitted in the UL grant1, only part1of the data in the LCH1is included in a MAC SDU1for transmitting in the UL grant1.

After forming the MAC SDU1, the MAC entity of the UE may decrement B1by the size of the MAC SDU1and the value of the B1may be (PBR1×N×T)−the size of the MAC SDU1, which is negative as shown inFIG.2. In another aspect, the data in the LCH2is not transmitted, and thus the MAC entity of the UE does not perform subtraction to B2.

After that, at a time period TP2, a UL grant2may be available for the UE to transmit uplink user data. The UE may allocate the UL grant to the data in the logical channels with Bj>0 in a decreasing priority order. From the time when MAC SDU1is transmitted until the UL grant2appears, both B1and B2are incremented. However, at the time when the UL grant2appears, B1is still negative, and thus the data in CH2should be allocated with the resource of the UL granted2. As shown inFIG.2, all the data in the LCH2is included in a MAC SDU2for transmitting in the UL grant2. After forming the MAC SDU2, the MAC entity of the UE may decrement B2by the size of the MAC SDU2. B2may be zero as shown inFIG.2.

After that, at a time period TP3, a UL grant3may be available for the UE to transmit uplink user data. The UE may allocate the UL grant to the data in the logical channels with Bj>0 in a decreasing priority order. From the time when MAC SDU2is transmitted until the UL grant3appears, both B1and B2are incremented. At the time when the UL grant2appears, B1is positive, and thus the data in LCH1should be allocated with the resource of the UL granted3first. As shown inFIG.2, part2of the data in the LCH1is included in a MAC SDU3for transmitting in the UL grant3. After forming the MAC SDU3, the MAC entity of the UE may decrement B1by the size of the MAC SDU3. The above process is continuously executed over time. Persons skilled in the art can understand that two logical channels are only for illustrative purposes, according to some other embodiments; the UE may include one or more logical channels and the procedure are similar as stated above.

The LCP procedure inFIG.2ensures the fairness of data transmission in different logical channels, especially for the logical channels with low priorities. However, the LCP procedure used in the small data transmission of the UE in the RRC_IDLE state or RRC_INACTIVE state may bring some issues. For example,FIG.3illustrates a LDP procedure for small data transmission according to some embodiments of the present application.

Referring toFIG.3, each of the UL granted1, the UL granted2, and UL grant3may be obtained based on an EDT procedure, may be obtained based on a RACH procedure, may be the configured grant type 1 resources, or may be the resources small data transmission obtained from any other procedures. For example, UL granted1may be obtained based on a RACH procedure, whereas UL granted2and UL grant3may be similar as or may reuse the configured grant type 1 resources specified in 3GPP standard documents. The operation before transmitting the MAC SDU1are the same as that illustrated inFIG.2. The difference is thatFIG.3involves small data transmission of the UE in the RRC_IDLE state or RRC_INACTIVE state. That is, after transmitting the MAC SDU1in the UL grant1, at time t1, the UE may receive an RRC release message including a suspend configuration IE, an RRC early data complete message, or a MAC reset message following small data transmission. All of these messages may indicate resetting the MAC. Given this, although B1is negative after transmitting the MAC SDU1, it will be initialized to zero after receiving the message indicating resetting the MAC.

After that, at a time period TP2, a UL grant2may be available for the UE to transmit uplink user data. The UE may allocate the UL grant to the data in the logical channels with Bj>0 in a decreasing priority order. From the time when MAC SDU1is transmitted until the UL grant2appears, both B1and B2are incremented. At the time when the UL grant2appears, B1is incremented to a positive value, and thus the data in LCH1should be firstly transmitted in the UL granted2. As shown inFIG.3, part2of the data in the LCH1and part1of the data in LCH2is multiplexed to a MAC PDU2for transmitting in the UL grant2. The MAC PDU2may include MAC SDU2and at least one sub-header. MAC SDU2may include part2of the data in the LCH1and part1of the data in LCH2. After forming the MAC SDU2, the values of B1and B2are updated according to the size of MAC SDU which and may be positive or negative. However, both B1and B2may be initialized to zero after receiving the message indicating resetting the MAC in time t2.

Given the above, it can be seen fromFIG.3that priority of the logical channel decides the sequence for assembling data in the UL grant and Bj doesn't affect anything. It is unfair to logical channels with the low priorities because the logical channels with high priorities always transmit data firstly. For example, part2of the data in LCH2which should be transmitted in UL grant2has to wait for the UL grant3for transmitting.

In addition, for the EDT procedure for CP CIoT EPS optimizations, the uplink user data may be encapsulated as NAS protocol data unit (PDU) in an uplink RRC message. The UE may transmit an RRC early data request message concatenating uplink the user data. There is no QoS related procedure in an access stratum (AS) layer. However, all the traffic in NR may have been configured with QoS parameters. Therefore, the technical solutions to satisfy the QoS in the procedure for CP optimizations are necessary.

Accordingly, embodiments of the present application can keep the fairness of data in all the logical channels when the data is transmitted as small data transmission as well as managing QoS when the uplink user data is transmitted using a CP solution (e.g., including the uplink user data in the NAS message concatenated in an RRC message). More details on embodiments of the present application will be illustrated in the following text in combination with the appended drawings.

FIG.4is a flow chart illustrating a method for small data transmission according to some embodiments of the present application. The method may be performed by a UE103in an RRC_IDLE state or in an RRC-INACTIVE state as shown inFIG.1.

As shown inFIG.4, in step402, the UE103may maintain a priority variable for each logical channel of at least one logical channel. The at least one logical channel may be used for a small data transmission by the UE103.

According to some embodiments of the present application, the at least one logical channel may be all the logical channels of the UE. In these embodiments, the UE may consider that all the logical channels can be used for the small data transmission.

According to some embodiments of the present application, the at least one logical channel may be determined based on configuration information from a BS and/or a logical channel selection procedure for an UL grant. For example, assuming that the UE has five logical channels numbered as0,1,2,3, and4, in an embodiment of the present application, the configuration information from the BS may indicate that logical channels0,1,2can be used for the small data transmission, then the at least one logical channel may be logical channels0,1,2. In another embodiment of the present application, the at least one logical channel may be logical channels1,2,3determined by a logical channel selection procedure as specified in 3GPP standard documents. In yet another embodiment of the present application, the configuration information from the BS may indicate that logical channels1,2,3,4can be used for small data transmission, and the UE may perform a logical channel selection procedure as specified in 3GPP standard documents to select logical channels1,2,3for small data transmission. In this case, the at least one logical channels may be logical channels1,2, and3determined based on the configuration information from the BS and the logical channel selection procedure.

According to some embodiments of the present application, the small data transmission may include a UP-based small data transmission and CP-based small data transmission. The UP-based small data transmission may include transmitting the small data multiplexing with an RRC message. The CP-based small data transmission may include transmitting the small data in a NAS message concatenated in an RRC message.

According to some embodiments of the present application, the UE103may transmit small data through a RACH-based scheme (e.g., 2-step RACH scheme or 4-step RACH scheme as specified in 3GPP standard documents). For example, the small data may be transmitted using MSGA in 2-step RACH scheme or MSG3 in 4-step RACH scheme. In an embodiment of the present application, the BS101may transmit a broadcast message indicating that the network supports the small data transmission.

According to some embodiments of the present application, the UL grant for transmitting the small data may be preconfigured resources (e.g., the configured grant type 1 resources as specified in 3GPP standard documents). In an embodiment of the present application, when the network releases the UE to the RRC_INACTIVE state, the pre-configured resources may be configured with the release message for small data transmission.

According to some embodiments of the present application, the UE may support an UP-based small data transmission. In these embodiments of the present application, the priority variable maintained for each logical channel of the at least one logical channel may be Bj as specified in 3GPP standard documents. For example, assuming that the at least one logical channel used for small data transmitting is logical channel1,2,3and4, and thus the UE may maintain B1, B2, B3, and B4for logical channel1,2,3and4, respectively.

The initialization procedure for Bj may be the same as those specified in 3GPP standard documents. For example, the MAC entity of the UE103may initialize Bj of the logical channel to zero when the logical channel is established.

For each logical channel j, the MAC entity of the UE may increment Bj by the product PBR×T before every instance of a LCP procedure to determine a first value, wherein T is the time elapsed since Bj was last incremented; if the first value is greater than the bucket size (i.e. PBR×BSD) of the logical channel j, the UE103may set Bj to the bucket size.

When performing a first small data transmission, a first LCP procedure may be applied. In the first LCP procedure, the MAC entity of the UE103may allocate resources to the at least one logical channel as follows: all the allowed logical channels with Bj>0 of the at least one logical channel are allocated resources in a decreasing priority order. Persons skilled in the art can understand that the first small data transmission may refer to the initial small data transmission after the initialization procedure or any other small data transmission after the initial small data transmission. Similarly, the first LCP procedure may refer to the initial LCP procedure after the initialization procedure or any other LCP procedure after the initial LCP procedure.

After performing the first LCP procedure, in step404, the MAC entity of the UE103may determine the value of Bj for each logical channel j of the at least one logical channel. Determining the value of Bj for each logical channel j may include decrementing Bj for each logical channel by the total size of MAC SDU(s) served to logical channel j, wherein the value of the Bj before performing decrementing may be determined based on the incrementing procedure as stated above.

In step406, the UE103may receive a message indicating a MAC reset. According to some embodiments of the present application, the message indicating the MAC reset may include one of: an RRC release message including a suspend configuration IE, an RRC early data complete message; and a MAC reset message following small data transmission.

In step408, after receiving the message, in a second LCP procedure subsequent to the first LCP procedure, the UE may use the value of the Bj determined after the first LCP procedure as an initial value of the Bj for each logical channel j of the at least one logical channel. In these embodiments, step408may be implemented by the following procedures. For example, in response to receiving the message, the UE103may store the value of the Bj for each logical channel determined after the first LCP procedure as a temporary value Bj_temp for each logical channel in an RRC layer or a MAC Inver. In an embodiment of the present application, at the moment of receiving the message or when receiving the message, the UE103may store the value of the Bj for each logical channel as a temporary value Bj_temp for each logical channel in an RRC layer or a MAC layer. After resetting the MAC, the UE103may set the temporary value Bj_temp as the initial value of the Bj for each logical channel (e.g., set Bj=Bj_temp) or for the configured logical channels which are configured to allow the small data transmission, and thus the Bj may be used in a following second LCP procedure for a second small data transmission. In an embodiment of the present application, the exact moment(s) when the UE updates Bj between LCP procedures is up to UE implementation, as long as Bj is up to date at the time when a grant is processed by the LCP procedure or after MAC is reset.

According to some other embodiments of the present application, the UE may support an UP-based small data transmission. In these embodiments of the present application, the priority variable maintained for each logical channel of the at least one logical channel may be a new priority variable (e.g., Bj_smalldata) different from Bj as specified in 3GPP standard documents. The new priority variable (e.g., Bj_smalldata) is not affected by a MAC reset operation. The new priority variable may be configured or predefined for small data transmission, for example, a CP-based small data transmission and/or an UP-based small data transmission. In an embodiment of the present embodiment of the present application, the 3GPP standard documents may define that the new priority variable is used for small data transmission. In an embodiment of the present embodiment of the present application, the new priority variable may be a MAC parameter.

For example, assuming that the at least one logical channel used for small data transmitting is logical channel1,2,3and4, and thus the UE may maintain B1_smalldata, B2_smalldata, B3_smalldata, and B4_smalldata for logical channel1,2,3and4, respectively.

The MAC entity of the UE103may initialize Bj_smalldata of the logical channel to zero when UE103initiates a small data transmission or when UE103is released to INACTIVE state with the configuration of small data transmission or when the logical channel is established.

For each logical channel j, the MAC entity of the UE may increment Bj_smalldata by the product PBR×T before every instance of a LCP procedure to determine a first value, wherein T is the time elapsed since Bj_smalldata was last incremented; if the first value is greater than the bucket size (i.e. PBR×BSD) of the logical channel j, the UE103may set Bj_smalldata to the bucket size. In an embodiment of the present application, the exact moment(s) when the UE updates Bj_smalldata between LCP procedures is up to UE implementation, as long as Bj_smalldata is up to date at the time when a grant is processed by the LCP procedure or after MAC is reset.

When performing a first small data transmission, a first LCP procedure may be applied. In the first LCP procedure, the MAC entity of the UE103may allocate resources to the at least one logical channel as the following steps: step1: all the allowed logical channels with Bj_smalldata>0 of the at least one logical channel are allocated resources in a decreasing priority order. If the PBR of a logical channel is set to infinity, the MAC entity shall allocate resources for all the data that is available for transmission on the logical channel before meeting the PBR of the lower priority logical channel(s). Persons skilled in the art can understand that the first small data transmission may refer to the initial small data transmission after the initialization procedure or any other small data transmission after the initial small data transmission. Similarly, the first LCP procedure may refer to the initial LCP procedure after the initialization procedure or any other LCP procedure after the initial LCP procedure.

Step2: after performing the first LCP procedure, the MAC entity of the UE103may determine the value of Bj_smalldata for each logical channel j of the at least one logical channel (i.e., step404as shown inFIG.4). Determining the value of Bj_smalldata for each logical channel j may include decrementing Bj_smalldata for each logical channel by the total size of MAC SDU(s) served to logical channel j, wherein the value of the Bj_smalldata before performing decrementing may be determined based on the incrementing procedure as stated above. The Bj_smalldata may be negative after performing the first LCP procedure.

Step3: if any resources remain, all the logical channels of the at least one logical channels are served in a strict decreasing priority order regardless of the value of Bj_smalldata until either the data for that logical channel or the UL grant is exhausted, whichever comes first. Logical channels configured with equal priority should be served equally. According to some embodiments of the present application, step1and step2may be not performed by the UE103.

In step406, the UE103may receive a message indicating a MAC reset. According to some embodiments of the present application, the message indicating the MAC reset may include one of: an RRC release message including a suspend configuration IE, an RRC early data complete message; and a MAC reset message following small data transmission.

In step408, after receiving the message, in a second LCP procedure subsequent to the first LCP procedure, the UE may use the value of the Bj_smalldata determined after the first LCP procedure as an initial value of the Bj_smalldata for each logical channel j of the at least one logical channel. As stated above, the Bj_smalldata is a new priority variable which is not affected by the MAC reset operation. That is, in response to receiving the message, the UE103may not initialize the priority variable Bj_smalldata for each logical channel j to zero, such that the value of the Bj_smalldata determined after the first LCP procedure may be used in a following second LCP procedure for a second small data transmission.

According to some embodiments of the present application, the UE may support a CP-based small data transmission. In an embodiment of the present application, according to the mapping rule of flow to DRB and DRB to logical channel, the AS layer may find the logical channel j which corresponds to the NAS flow that the NAS data is transmitted. In an embodiment of the present application, the CP-based small data transmission may be limited to some flows which configured by a mobility management entity (MME) or an access and mobility management function (AMF).

In these embodiments, the priority variable maintained for each logical channel of the at least one logical channel may be Bj as specified in 3GPP standard documents. For example, assuming that the at least one logical channel used for small data transmitting is logical channel1,2,3and4, and thus the UE may maintain B1, B2, B3, and B4for logical channel1,2,3and4, respectively.

The initialization procedure for Bj may be the same as those specified in 3GPP standard documents. For example, the MAC entity of the UE103may initialize Bj of the logical channel to zero when the logical channel is established.

For each logical channel j, the MAC entity of the UE may increment Bj by the product PBR×T before every instance of a LCP procedure to determine a second value, wherein T is the time elapsed since Bj was last incremented; if the second value is greater than the bucket size (i.e. PBR×BSD) of the logical channel j, the UE103may set Bj to the bucket size.

When performing a first small data transmission, a first LCP procedure may be applied. In the CP-based small data transmission, the first small data may be included in a NAS message concatenated in an RRC message for transmitting via logical channel(s). In the first LCP procedure, the MAC entity of the UE103may allocate resources to the logical channel(s) for small data transmission. Persons skilled in the art can understand that the first small data transmission may refer to the initial small data transmission after the initialization procedure or any other small data transmission after the initial small data transmission. Similarly, the first LCP procedure may refer to the initial LCP procedure after the initialization procedure or any other LCP procedure after the initial LCP procedure.

After performing the first LCP procedure, in step404, the MAC entity of the UE103may determine the value of Bj for each logical channel j of the at least one logical channel. Before determining the value of Bj, a lower layer of the UE103may retrieve a size of the data transmitted by a higher layer served to each logical channel from a higher layer. In an embodiment of the present application, the lower layer may be an AS layer. The AS layer may include one of more of the followings: an RRC layer, a MAC layer, a packet data convergence protocol (PDCP), radio link control (RLC) layer, and a physical (PHY) layer. In an embodiment of the present application, the higher layer may be a NAS layer.

After that, the UE103may determine a total size of MAC SDU served to each logical channel based on at least one of followings: the size the data transmitted by the higher layer for the logical channel, a size of a PDCP header, a size of an RLC header, and a size of a service data adaption protocol (SDAP) header. For example, in the case that the SDAP layer is configured for the UE, a total size of MAC SDU served to each logical channel equals a sum of the size the data transmitted by the higher layer, the size of the PDCP header, the size of the RLC header, and the size of a SDAP header. Then, the UE may determine the value of the priority variable Bj based on the total size of MAC SDU served to each logical channel. For example, determining the value of Bj for each logical channel j may include decrementing Bj for each logical channel by the total size of MAC SDU(s) served to logical channel j, wherein the value of the Bj before performing decrementing may be determined based on the incrementing procedure as stated above.

In an embodiment of the present application, in response to that the value of the priority variable Bj is negative, the lower layer of the UE103may transmit a first indication to the higher layer to suspend small data transmission. After some time instances, the UE103may transmit a second indication to the higher layer to allow small data transmission when the Bj>0.

In another embodiment of the present application, in response to that the value of the priority variable Bj is positive, the lower layer of the UE103may transmit a second indication to the higher layer to allow small data transmission.

In step406, the UE103may receive a message indicating a MAC reset. According to some embodiments of the present application, the message indicating the MAC reset may be one of: an RRC release message including a suspend configuration IE, an RRC early data complete message; and a MAC reset message following small data transmission.

In step408, after receiving the message, in a second LCP procedure subsequent to the first LCP procedure, the UE may use the value of the Bj determined after the first LCP procedure as an initial value of the Bj for each logical channel j of the at least one logical channel. In these embodiments, step408may be implemented by the following procedures. For example, in response to receiving the message, the UE103may store the value of the Bj for each logical channel determined after the first LCP procedure as a temporary value Bj_temp for each logical channel in an RRC layer or a MAC layer. After resetting the MAC, the UE103may set the temporary value Bj_temp as the initial value of the Bj for each logical channel (e.g., set Bj=Bj_temp), and thus the Bj may be used in a following second LCP procedure for a second small data transmission.

According to some other embodiments of the present application, the UE may support a CP-based small data transmission. In an embodiment of the present application, according to the mapping rule of flow to logical channel, the AS layer may find the logical channel j which corresponds to the NAS flow that the NAS data is transmitted. In an embodiment of the present application, the CP-based small data transmission may be limited to some flows which configured by a mobility management entity (MME) or an access and mobility management function (AMF).

In these embodiments of the present application, the priority variable maintained for each logical channel of the at least one logical channel may be a new priority variable (e.g., Bj_smalldata) different from Bj as specified in 3GPP standard documents. The new priority variable (e.g., Bj_smalldata) is not affected by a MAC reset operation. The new priority variable may be configured or predefined for small data transmission, for example, a CP-based small data transmission and/or an UP-based small data transmission. In an embodiment of the present embodiment of the present application, the 3GPP standard documents may define that the new priority variable is used for small data transmission. In an embodiment of the present embodiment of the present application, the new priority variable may be a MAC parameter.

For example, assuming that the at least one logical channel used for small data transmitting is logical channel1,2,3and4, and thus the UE may maintain B1_smalldata, B2_smalldata, B3_smalldata, and B4_smalldata for logical channel1,2,3and4, respectively.

The MAC entity of the UE103may initialize Bj_smalldata of the logical channel to zero when UE103initiates a small data transmission or when UE103is released to INACTIVE state with the configuration of small data transmission or when the logical channel is established.

For each logical channel j, the MAC entity of the UE may increment Bj_smalldata by the product PBR×T before every instance of a LCP procedure to determine a second value, wherein T is the time elapsed since Bj_smalldata was last incremented; if the second value is greater than the bucket size (i.e. PBR×BSD) of the logical channel j, the UE103may set Bj_smalldata to the bucket size. In an embodiment of the present application, the exact moment(s) when the UE updates Bj_smalldata between LCP procedures is up to UE implementation, as long as Bj_smalldata is up to date at the time when a grant is processed by the LCP procedure or after MAC is reset.

When performing a first small data transmission, a first LCP procedure may be applied. In the CP-based small data transmission, the first small data may be included in a NAS message concatenated in an RRC message for transmitting via logical channel(s). In the first LCP procedure, the MAC entity of the UE103may allocate resources to the logical channel(s) for small data transmission. Persons skilled in the art can understand that the first small data transmission may refer to the initial small data transmission after the initialization procedure or any other small data transmission after the initial small data transmission. Similarly, the first LCP procedure may refer to the initial LCP procedure after the initialization procedure or any other LCP procedure after the initial LCP procedure.

After performing the first LCP procedure, in step404, the MAC entity of the UE103may determine the value of Bj_smalldata for each logical channel j of the at least one logical channel. Before determining the value of Bj_smalldata, a lower layer of the UE103may retrieve a size of the data transmitted by a higher layer served to each logical channel from a higher layer. In an embodiment of the present application, the lower layer may be an AS layer. The AS layer may include one of more of the followings: an RRC layer, a MAC layer, a PDCP, an RLC layer, and a PHY layer. In an embodiment of the present application, the higher layer may be a NAS layer.

After that, the UE103may determine a total size of MAC SDU served to each logical channel based on at least one of followings: the size the data transmitted by the higher layer for the logical channel, a size of a PDCP header, a size of an RLC header, and a size of a SDAP header. For example, in the case that the SDAP layer is configured for the UE, a total size of MAC SDU served to each logical channel equals a sum of the size the data transmitted by the higher layer, the size of the PDCP header, the size of the RLC header, and the size of a SDAP header. Then, the UE may determine the value of the priority variable Bj_smalldata based on the total size of MAC SDU served to each logical channel. For example, determining the value of Bj_smalldata for each logical channel j may include decrementing Bj_smalldata for each logical channel by the total size of MAC SDU(s) served to logical channel j, wherein the value of the Bj_smalldata before performing decrementing may be determined based on the incrementing procedure as stated above.

In an embodiment of the present application, in response to that the value of the priority variable Bj_smalldata is negative, the lower layer of the UE103may transmit a first indication to the higher layer to suspend small data transmission. After some time instances, the UE103may transmit a second indication to the higher layer to allow small data transmission when the Bj_smalldata>0.

In another embodiment of the present application, in response to that the value of the priority variable Bj_smalldata is positive, the lower layer of the UE103may transmit a second indication to the higher layer to allow small data transmission.

If any resources remain, all the logical channels of the at least one logical channels are served in a strict decreasing priority order regardless of the value of Bj_smalldata until either the data for that logical channel or the UL grant is exhausted, whichever comes first. Logical channels configured with equal priority should be served equally.

In step406, the UE103may receive a message indicating a MAC reset. According to some embodiments of the present application, the message indicating the MAC reset may be one of: an RRC release message including a suspend configuration IE, an RRC early data complete message; and a MAC reset message following small data transmission.

In step408, after receiving the message, in a second LCP procedure subsequent to the first LCP procedure, the UE may use the value of the Bj_smalldata determined after the first LCP procedure as an initial value of the Bj_smalldata for each logical channel j of the at least one logical channel. As stated above, the Bj_smalldata is a new priority variable which is not affected by the MAC reset operation. That is, in response to receiving the message, the UE103may not initialize the priority variable Bj_smalldata for each logical channel j to zero, such that the value of the Bj_smalldata determined after the first LCP procedure may be used in a following second LCP procedure for a second small data transmission.

FIG.5illustrates a simplified block diagram of an apparatus500for small data transmission according to some embodiments of the present application. The apparatus500may be a UE103as shown inFIG.1.

Referring toFIG.5, the apparatus500may include at least one non-transitory computer-readable medium502, at least one receiving circuitry504, at least one transmitting circuitry506, and at least one processor508. In some embodiment of the present application, at least one receiving circuitry504and at least one transmitting circuitry506and be integrated into at least one transceiver. The at least one non-transitory computer-readable medium502may have computer executable instructions stored therein. The at least one processor508may be coupled to the at least one non-transitory computer-readable medium502, the at least one receiving circuitry504and the at least one transmitting circuitry506. The computer executable instructions can be programmed to implement a method with the at least one receiving circuitry504, the at least one transmitting circuitry506and the at least one processor508. The method can be a method according to an embodiment of the present application, for example, the method shown inFIG.4.

The method according to embodiments of the present application can also 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 application. For example, an embodiment of the present application provides an apparatus for emotion recognition from speech, including a processor and a memory. Computer programmable instructions for implementing a method for emotion recognition from speech are stored in the memory, and the processor is configured to perform the computer programmable instructions to implement the method for emotion recognition from speech. The method may be a method as stated above or other method according to an embodiment of the present application.

An alternative embodiment preferably implements the methods according to embodiments of the present application in a non-transitory, computer-readable storage medium storing computer programmable instructions. The instructions are preferably executed by computer-executable components preferably integrated with a network security system. The non-transitory, computer-readable storage medium may be stored on any suitable computer readable media such as RAMs, ROMs, flash memory, EEPROMs, optical storage devices (CD or DVD), hard drives, floppy drives, or any suitable device. The computer-executable component is preferably a processor but the instructions may alternatively or additionally be executed by any suitable dedicated hardware device. For example, an embodiment of the present application provides a non-transitory, computer-readable storage medium having computer programmable instructions stored therein. The computer programmable instructions are configured to implement a method for emotion recognition from speech as stated above or other method according to an embodiment of the present application.