CN110753076A

CN110753076A - Data sending and receiving method, device and storage medium

Info

Publication number: CN110753076A
Application number: CN201810820675.9A
Authority: CN
Inventors: 孙军帅; 王莹莹; 黄学艳; 韩星宇; 易芝玲
Original assignee: China Mobile Communications Group Co Ltd; China Mobile Communications Ltd Research Institute
Current assignee: China Mobile Communications Group Co Ltd; China Mobile Communications Ltd Research Institute
Priority date: 2018-07-24
Filing date: 2018-07-24
Publication date: 2020-02-04
Anticipated expiration: 2038-07-24
Also published as: CN110753076B

Abstract

The invention discloses a data sending and receiving method, a device and a storage medium, which are used for realizing PDU transmission and reducing the expenditure of network transmission resources. The data transmission method comprises the steps that SDAP PDU is transmitted through MAC CE, and the subheader of the extended MAC PDU comprises a fixed length identifier FDF; and the data transmission method comprises the following steps: the MAC layer receives RLC PDU transmitted by the RLC layer to obtain MAC SDU to be transmitted, wherein the RLC PDU is obtained by the RLC layer according to PDCP PDU transmitted by the PDCP layer; if the length of the MAC SDU to be transmitted is 1 byte and the number of the MAC SDU to be transmitted is 1, modifying an identification value corresponding to FDF in a subheader of the constructed MAC PDU when the MAC PDU is constructed according to the received MAC SDU; and sending the constructed MAC PDU to the MAC layer of the opposite terminal.

Description

Data sending and receiving method, device and storage medium

Technical Field

The present invention relates to the field of wireless communication technologies, and in particular, to a method, an apparatus, and a storage medium for transmitting and receiving data.

Background

The LTE (Long Time Evolution) radio interface protocol stack includes a user plane protocol stack and a control plane protocol stack. A User Plane (UP) protocol stack is a protocol cluster used for User data transmission, and a Control Plane (CP) protocol stack is a protocol cluster used for Control signaling transmission of a system. Wherein, the user plane protocol stack includes: a physical layer (PHY), a Media Access Control (MAC) layer, a Radio Link Control (RLC) layer, a Media Access Control (MAC) layer, and a Packet Data Convergence Protocol (PDCP) layer. The Control plane protocol stack further includes a Radio Resource Control (RRC) layer and a non-access stratum layer based on the above architecture. At a transmitting end, a Service Data Unit (SDU) is received from a higher layer to provide a Service for the layer, and a Protocol Data Unit (PDU) is output to a lower layer. For example, the RLC layer receives packets from the PDCP, which are PDCP PDUs for the PDCP layer, but RLC SDUs for the RLC layer. The 5G NR (New Radio, New air interface) Radio protocol stack is also divided into a user plane and a control plane. Compared with an LTE protocol stack, the NR user plane has one more SDAP layer, and the user plane protocols are as follows from top to bottom: a Service Data Adaptation Protocol (SDAP) layer, a packet data Protocol (PDCP) layer, a Radio Link Control (RLC) layer, a Media Access Control (MAC) layer, and a physical layer. The NR control plane protocol is almost the same as the LTE protocol stack, and from top to bottom: NAS layer, RRC layer, PDCP layer, RLC layer, MAC layer, PHY layer. The SDAP layer is mainly used for mapping between QoS flows and radio bearers (DRBs).

An End Marker is defined on the UE (User Equipment) side. The PDU is sent to the network side SDAP by the UE side SDAP entity to indicate to stop the QoS flow to DRB mapping. The PDU is called an End-MarkerrPDU, has a length of one byte, and carries a D/C (Data/Control) field and a QFI (quality of service) flow ID), wherein the D/C field is used for indicating whether the PDU or the Data PDU.

The length of the End-MarkerPDU is only one byte, and according to the definition of the current PDCP protocol sublayer, the PDCP can only process data packets under two modes of AM RLC and UM RLC, namely, the End-MarkerPDU sent from the SDAP protocol sublayer is added with a PDCP PDU header (head) with 2-3 bytes and an MAC-I with 4 bytes after being processed by the PDCP protocol sublayer. And after the PDCP PDU bearing the End-Marker PDU is processed by an RLC protocol sublayer, an RLC header with 1-3 bytes is added. After the RLC PDU carrying the End-MarkerPDU is processed by the MAC protocol sublayer, the length of the MAC sub-header of 2 bytes is increased. Therefore, when the End-MarkerPDU with the length of one byte is sent, various head expenses of 9-12 bytes are needed to be added, and waste of network transmission resources is caused.

Disclosure of Invention

The embodiment of the invention provides a data sending and receiving method, a device and a storage medium, which are used for realizing PDU transmission and reducing the expenditure of network transmission resources.

In a first aspect, a data transmission method implemented by a transmitting end is provided, wherein a service data adaptation protocol SDAP PDU is transmitted through a media access control unit MAC CE, and a subheader of an extended MAC PDU comprises a fixed length identifier FDF; and

the data sending method comprises the following steps:

the MAC layer receives RLC protocol data unit PDU transmitted by the RLC layer under the control of the wireless link to obtain MAC service data unit SDU to be transmitted, wherein the RLC PDU is obtained by the RLC layer according to PDCP PDU transmitted by the PDCP layer;

if the length of the MAC SDU to be transmitted is 1 byte and the number of the MAC SDU to be transmitted is 1, modifying an identification value corresponding to FDF in a subheader of the constructed MAC PDU when the MAC PDU is constructed according to the received MAC SDU;

and sending the constructed MAC PDU to the MAC layer of the opposite terminal.

Optionally, the PDCP PDU is obtained according to the following procedure:

the PDCP layer receives the SDAP PDU sent by the SDAP layer to obtain a PDCP service data unit SDU;

and the PDCP layer sends the PDCP SDU to an RLC layer as a PDCP PDU.

Optionally, the RLC PDU is obtained according to the following procedure:

the RLC layer receives RLC SDU obtained by PDCP PDU transmitted by the PDCP layer;

the RLC layer takes the RLC SDU as an RLC PDU;

an uplink dedicated traffic channel UL DTCH, and/or a downlink DL DTCH, and/or a UL/DL dedicated control channel DCCH of the RLC layer transmits RLC PDUs to the MAC layer using a transparent transmission mode.

Optionally, the extending the MAC PDU subheader containing the FDF identifier includes:

selecting available bits in a subheader of the MAC PDU to carry the fixed length identity FDF.

Optionally, the data sending method further includes:

and if the length of the MAC SDU to be transmitted is 1 byte and the number of the MAC SDU to be transmitted is more than 1, carrying a length field in a subheader of the constructed MAC PDU, wherein the length field is used for indicating the length of the MAC PDU.

Optionally, the data sending method further includes:

and modifying the identification value corresponding to the FDF in the subheader of the constructed MAC PDU.

Optionally, the MAC layer determines the number of MAC SDUs according to the following method:

and determining the number of the MAC SDUs to be transmitted according to the same logic control channel identification (LCID).

In a second aspect, a data receiving method is provided, wherein a media access control unit (MAC CE) is used to send a Service Data Adaptation Protocol (SDAP) PDU, and a subheader of an extended MAC PDU comprises a fixed length identifier (FDF); and

the data receiving method comprises the following steps:

the MAC layer receives the MAC PDU transmitted by the method of any claim 1 to 7;

the MAC layer determines the length of the MAC PDU according to the identification value of the fixed-length identification FDF carried in the received MAC protocol data unit PDU;

the MAC layer analyzes the MAC PDU with corresponding quantity according to the determined length of the MAC PDU to obtain an MAC service data unit SDU; and are

The MAC layer sends the obtained MAC SDU to a radio link control RLC layer, the RLC layer serves as an RLC PDU and transmits the RLC PDU to a packet data convergence protocol PDCP layer, and the PDCP layer transmits the RLC PDU to a service data adaptation protocol SDAP layer.

Optionally, the MAC layer sends the obtained MAC SDU to the RLC layer, and the RLC layer passes the MAC SDU as an RLC pdu to the PDCP layer, including:

the MAC layer sends the obtained MAC SDU to the RLC layer by using an uplink dedicated traffic channel UL DTCH, and/or a downlink DL DTCH, and/or a UL/DL dedicated control channel DCCH in a transparent transmission mode; and

the RLC layer receives the MAC SDU sent by the MAC layer to obtain an RLC PDU;

and the RLC layer sends the RLC PDU as an RLC SDU to the PDCP layer.

Optionally, the PDCP layer passes the RLC SDU to the SDAP layer according to the following procedure:

the PDCP layer receives RLC SDU sent by the RLC layer to obtain PDCP PDU;

the PDCP layer transmits PDCP PDUs as PDCP SDUs to the SDAP layer.

Optionally, determining the length of the MAC PDU according to an identifier value of a fixed length identifier FDF carried in the MAC PDU includes:

and if the length of the MAC PDU is determined to be larger than 1 according to the identification value of the fixed length identification FDF carried in the MAC PDU, determining the length of the MAC PDU according to the length domain carried in the MAC PDU.

Optionally, the data receiving method further includes:

after receiving the PDCP SDU transmitted by the PDCP layer, the SDAP layer determines the length of the PDCP SDU;

and analyzing the corresponding number of PDCP SDUs according to the length of the PDCP SDUs to obtain the SDAP PDU.

In a third aspect, a data transmitting apparatus is provided, where a service data adaptation protocol SDAP PDU is transmitted by a media access control unit MAC CE, and a subheader of an extended MAC PDU includes a fixed length identifier FDF; and

the data transmission device includes:

a Packet Data Convergence Protocol (PDCP) unit for transparently transmitting a PDCP Protocol Data Unit (PDU) to a Radio Link Control (RLC) unit;

the RLC unit is used for obtaining the RLC PDU according to the received PDCP PDU and transmitting the RLC PDU to the media access control MAC unit;

and the MAC unit is used for obtaining the MAC SDU to be transmitted according to the received RLC PDU, modifying the identification value corresponding to the FDF in the subheader of the constructed MAC PDU and sending the constructed MAC PDU to the MAC unit of the opposite terminal when the MAC PDU is constructed according to the received MAC SDU if the length of the MAC SDU to be transmitted is 1 byte and the number of the MAC SDU to be transmitted is 1.

Optionally, the PDCP unit is configured to receive an SDAP PDU sent by the SDAP unit to obtain a PDCP service data unit SDU; the received PDCP SDU is transmitted to the RLC unit as a PDCP PDU.

Optionally, the RLC unit is configured to receive an RLC SDU obtained from the PDCP PDU passed through by the PDCP unit; taking the RLC SDU as an RLC PDU; the RLC PDUs are sent to the MAC unit using a transparent mode on an uplink dedicated traffic channel UL DTCH, and/or a downlink DL DTCH, and/or a UL/DL dedicated control channel DCCH.

Optionally, the MAC unit is configured to select an available bit in a subheader of a MAC PDU to carry the fixed length identifier FDF.

Optionally, the MAC unit is further configured to carry a length field in a subheader of the constructed MAC PDU if the length of the MAC sdu to be transmitted is 1 byte and the number of the MAC sdu to be transmitted is greater than 1, where the length field is used to indicate the length of the MAC PDU.

Optionally, the MAC unit is further configured to modify an identification value corresponding to the FDF in a subheader of the constructed MAC PDU.

Optionally, the MAC unit is configured to determine the number of MAC sdus to be transmitted according to the same logical control channel identifier LCID.

In a fourth aspect, a data receiving apparatus is provided, in which a service data adaptation protocol SDAP PDU is transmitted through a media access control unit MAC CE, and a subheader of an extended MAC PDU includes a fixed length identifier FDF; and

the data receiving apparatus includes:

a MAC unit configured to receive a MAC PDU transmitted by any one of the data transmission methods; determining the length of the MAC PDU according to the identification value of the fixed length identification FDF carried in the received MAC protocol data unit PDU; analyzing the MAC PDU with corresponding quantity according to the determined length of the MAC PDU to obtain an MAC Service Data Unit (SDU); sending the obtained MAC SDU to a Radio Link Control (RLC) unit;

the RLC unit is used for transmitting the received MAC SDU serving as an RLC PDU to a packet data convergence protocol PDCP unit;

the PDCP unit is used for transmitting the received RLC PDU serving as a PDCP SDU to a service data adaptation protocol SDAP unit.

Optionally, the MAC unit is configured to send the obtained MAC SDU to the RLC unit using a transparent transmission mode by using an uplink dedicated traffic channel UL DTCH, and/or a downlink DL DTCH, and/or a UL/DL dedicated control channel DCCH;

and the RLC unit is used for receiving the MAC SDU sent by the MAC unit to obtain an RLC PDU, and sending the RLC PDU to the PDCP unit as the RLC SDU.

Optionally, the PDCP unit is configured to receive an RLC SDU sent by the RLC unit to obtain a PDCP PDU; and sending the PDCP PDU as a PDCP SDU to the SDAP unit.

Optionally, the MAC unit is further configured to determine the length of the MAC PDU according to a length field carried in the MAC PDU if it is determined that the length of the MAC PDU is greater than 1 according to an identifier value of a fixed length identifier FDF carried in the MAC PDU.

Optionally, the SDAP unit is further configured to determine a length of a PDCP SDU after receiving the PDCP SDU transparently transmitted by the PDCP unit; and analyzing the corresponding number of PDCP SDUs according to the length of the PDCP SDUs to obtain the SDAP PDU.

In a fifth aspect, a communication apparatus is provided, including: a processor, a memory, and a transceiver; the memory stores a computer program, and the processor is configured to read the program in the memory and execute the steps of any one of the data transmission methods or the data reception methods.

In a sixth aspect, a computer storage medium is provided, where the computer storage medium stores computer-executable instructions for causing the computer to perform the steps of any one of the data transmission method and the data reception method.

In the data transmitting and receiving method, device and storage medium provided by the embodiments of the present invention, at a transmitting end, after receiving a PDU sent by an SDAP layer to obtain a PDCP SDU, a PDCP PDU header is directly passed through to an RLC layer for processing without adding any PDCP PDU header or modifying the PDCP PDU, and in the RLC layer, a DTCH channel of a dedicated service channel of the PDCP layer transmits the RLC PDU to an MAC layer using a pass-through mode, and an FDF identifier is introduced into the MAC layer for identifying the length of the MAC SDU.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic diagram illustrating a transmission flow when a UE sends an End-Marker PDU to a base station according to an embodiment of the present invention;

FIG. 2 is a diagram illustrating transparent transmission of PDCP PDUs according to an embodiment of the present invention;

fig. 3 is a schematic flow chart of a data transmission method implemented by a PDCP layer in an embodiment of the present invention;

fig. 4 is a schematic flow chart of a data transmission method implemented by the RLC layer in the embodiment of the present invention;

FIG. 5 is a diagram illustrating a structure of a MAC subheader according to an embodiment of the present invention;

fig. 6 is a schematic flow chart of a data transmission method implemented by the RLC layer in the embodiment of the present invention;

fig. 7a is a schematic diagram of a MAC subheader format of an L field carrying 8 bits in the embodiment of the present invention;

fig. 7b is a schematic diagram of a MAC subheader format of an L field carrying 16 bits in the embodiment of the present invention;

fig. 8a is a schematic diagram of a MAC subheader format of an L domain carrying an FDF domain and 8 bits in the embodiment of the present invention;

fig. 8b is a schematic diagram of a MAC subheader format of an L domain carrying an FDF domain and 16 bits in the embodiment of the present invention;

fig. 9 is a schematic structural diagram of a data receiving method according to an embodiment of the present invention;

FIG. 10 is a schematic structural diagram of a data transmission apparatus according to an embodiment of the present invention;

FIG. 11 is a schematic structural diagram of a data receiving apparatus according to an embodiment of the present invention;

fig. 12 is a schematic structural diagram of a communication device according to an embodiment of the present invention.

Detailed Description

In order to reduce the resource overhead of transmitting the PDU, embodiments of the present invention provide a method, an apparatus, and a storage medium for transmitting and receiving data.

The preferred embodiments of the present invention will be described below with reference to the accompanying drawings of the specification, it being understood that the preferred embodiments described herein are merely for illustrating and explaining the present invention, and are not intended to limit the present invention, and that the embodiments and features of the embodiments in the present invention may be combined with each other without conflict.

The inventor finds that, in the process of transmitting the PDU, the PDCP layer, the RLC layer and the MAC layer need to perform different processing on the PDU, which increases the overhead of transmission resources. In view of this, in the embodiment of the present invention, a Transparent Mode (TM) is added in the PDCP layer, and a Transparent Mode (TM) of the RLC layer is enhanced. As shown in fig. 1, which is a schematic diagram of a transmission flow when a UE (user equipment) sends an End-MarkerPDU to a base station in an embodiment of the present invention, when an SDAP on a UE layer sends PDUs, the SDAP respectively passes through a PDCP layer and an RLC layer, and uses a transparent Transmission (TM) mode, and after reaching an MAC layer, the SDAP is added to the MAC PDU and sent to an air interface (radio interface (uu)). The following embodiments respectively describe the transparent transmission modes of the PDCP layer and the RLC layer in the embodiments of the present invention.

In the embodiment of the invention, a defined transparent transmission mode is defined in a PDCP protocol sublayer, the transparent transmission PDCP PDU consists of only one PDCP SDU, and the PDCP protocol sublayer does not add any PDCP PDU head to the PDCP SDU and does not modify the PDCP SDU. FIG. 2 is a diagram illustrating a transparent transmission of PDCP PDUs.

When the End-MarkerrPDU needs to be transmitted, the SDAP sends the End-MarkerrPDU to the PDCP, and the PDCP builds the PDCP PDU in a mode of transmitting the PDCP PDU after receiving the PDCP SDU and sends the PDCP PDU to the RLC layer.

Based on this, an embodiment of the present invention provides a data transmission method implemented by a PDCP layer, and as shown in fig. 3, the method may include the following steps:

s31, the PDCP layer receives the SDAP PDU sent by the SDAP layer to obtain the PDCP SDU.

S32, the PDCP layer determines the PDCP SDU as the PDCP PDU.

S33, the PDCP layer sends the PDCP PDUs to the RLC layer.

In the embodiment of the present invention, the existing Transparent Mode (Transparent Mode) is extended in the RLC layer, and the TM RLC adds the following Transparent modes in addition to the existing Transparent Mode: the TM RLC can transmit/receive RLC PDUs through at least an UL (Uplink) DTCH (Dedicated Traffic Channel) Channel, and can also transmit/receive RLC PDUs through a DL (Downlink) DTCH or UL/DL DCCH.

Based on this, an embodiment of the present invention provides a data transmission method implemented by an RLC layer, as shown in fig. 4, which may include the following steps:

s41, the RLC layer receives RLC SDU obtained from PDCP PDU sent by the PDCP layer.

In this step, the RLC layer receives RLC SDUs obtained from PDCP PDUs sent by the PDCP layer by using the method shown in fig. 3.

S42, the RLC layer takes the received RLC SDU as an RLC PDU.

S43, and the UL DTCH and/or DL DTCH of the RLC layer and/or UL/DL DCCH transmits RLC PDU to the MAC layer by using a transparent transmission mode.

In specific implementation, the UL DTCH (uplink dedicated traffic channel) and/or DL DTCH (downlink dedicated traffic channel) and/or UL/DL DCCH (uplink/downlink dedicated control channel) of the RLC layer transmit the resulting RLC PDU to the MAC layer using a transparent transmission mode.

Correspondingly, in the embodiment of the present invention, a new MAC subheader (subheader) for data transmission is introduced in the MAC layer to indicate that the currently transmitted PDU is a control PDU. Because the PDU is transparently transmitted in the PDCP layer and the RLC layer, the length of the transmitted control PDU is still 1 byte, and based on this, in the embodiment of the present invention, an identification bit (Flag) is added in the MAC subheader: FDF (Fixed Data Flag: Fixed length Flag), the length of the Flag bit is 1 bit (bit), and the FDF is used to identify whether the length of the corresponding MAC SDU is 1 byte.

Specifically, FDF is defined as follows:

FDF is 0, which means that the length of the MAC SDU is not fixed, and an L field indication length is required.

FDF ═ 1: indicating that the length of the MAC SDU is fixed to 1 byte.

It should be noted that the definition of the identification value of the FDF may be set according to actual needs, and the identification value definition provided in the embodiment of the present invention is only for illustration and is not limited to the present invention.

Based on this, when the FDF identifies the MAC SDU as data having a length of 1 byte (Oct), the MAC subheader does not need to include any length field for identifying the length of the MAC SDU. As shown in fig. 5, in the embodiment of the present invention, an available bit may be selected from a MAC SDU to carry an FDF, where the available bit may be an idle bit in the MAC SDU, for example, an R Field (Reserved Field) in the MAC SDU is modified into an FDF Field, or may be another bit that can accurately carry an FDF. In fig. 5, LCID is a Logical Channel ID (Logical Channel ID) that can uniquely identify one Logical Channel.

Based on this, an embodiment of the present invention provides a data transmission method implemented by a MAC layer, and as shown in fig. 6, the method may include the following steps:

s61, the MAC layer receives the RLC PDU transmitted by the RLC layer to obtain the MAC SDU to be transmitted.

In a specific implementation, the RLC layer may transmit RLC pdus to the MAC layer by using the method shown in fig. 3.

S62, if the length of the MAC SDU to be transmitted is 1 byte and the number is 1, when the MAC PDU is built according to the received MAC SDU, the identification value corresponding to the FDF is modified in the subheader of the built MAC PDU.

In this step, if the length of the MAC SDU to be transmitted is 1 byte and the number is 1, the MAC PDU is constructed according to the MAC subheader shown in fig. 5. Specifically, the MAC layer modifies the FDF field in the MAC subheader to 1.

In specific implementation, the MAC layer may determine whether the number of the MAC SDUs to be transmitted is 1 according to the LCID, and if only one MAC SDU to be transmitted is on the same logical channel (i.e., the LCIDs are the same), it may be determined that the number of the MAC SDUs to be transmitted is 1, otherwise, it may be determined that the number of the MAC SDUs to be transmitted is greater than 1.

And S63, sending the constructed MAC PDU to the MAC layer.

In this step, the MAC layer sends the constructed MAC PDU to the MAC layer of the receiving end through the air interface.

In specific implementation, when a plurality of End-markerpdus need to be transmitted, the MAC subheader carrying the L field may be used, and in specific implementation, the format of the existing MAC subheader may not be changed, that is, the existing MAC subheader does not need to carry the FDF identifier, as shown in fig. 7a and 7b, respectively, which are schematic diagrams of MAC subheader formats carrying the L field, where fig. 7a includes an L field with 8 bits, and fig. 7b includes an L field with 16 bits. The FDF identifier may also be carried, as shown in fig. 8a and 8b, respectively, which are schematic diagrams of MAC subheader structures carrying an FDF domain and an L domain, where fig. 8a includes an 8-bit L domain, and fig. 8b includes a 16-bit L domain.

Based on this, if the MAC layer determines that the number of MAC SDUs to be transmitted is greater than 1, a length field (L field) is carried in a subheader of the constructed MAC PDU, and the length field is used for indicating the length of the MAC PDU.

In specific implementation, whether the length field of 8 bits or the length field of 16 bits is used may be determined according to the number of mac sdus to be transmitted. The 8-bit L field may identify 255 bytes at most, i.e., may contain 255 MAC SDUs of 1 byte. It should be noted that, if the number of MAC SDUs to be transmitted is greater than 1, when a MAC PDU is constructed, an FDF identifier may be carried in the MAC subheader, that is, the MAC subheader format shown in fig. 8a and 8b is adopted, or an FDF identifier may not be carried, that is, the MAC subheader format shown in fig. 7a and 7b is adopted.

In specific implementation, if there are multiple MAC SDUs to be transmitted and the MAC subheader carrying the FDF field is used, the MAC may modify the identifier value corresponding to the FDF field to 0.

It should be noted that the data transmission method provided in the embodiment of the present invention may be used to transmit a service data adaptation protocol SDAP control PDU through a media access control unit MAC CE (media access control unit), where the data transmission method implemented by the transmitting end is described above, where protocol layers involved in each flow, for example, an MAC layer, an RLC layer, and a PDCP layer, are all protocol layers of the transmitting end.

At the receiving end, after receiving the information sent by the sending end, the receiving end firstly judges whether the information is a data unit according to the LCID domain in the MAC subheader. The LCID used by the data unit and the MAC CE gives a clear definition in the protocol, so the MAC layer at the receiving end can determine whether the received information is a data unit according to the LCID. If yes, firstly judging the FDF domain, if the FDF domain is 1, the data unit corresponding to the MAC subheader is a 1-byte data unit, analyzing the data unit and then sending the data unit to an upper layer; and if the FDF domain is 0, judging the F domain to obtain the length of the L domain, then obtaining the length of the data unit according to the length of the L domain, and then sending the length to the upper layer.

Based on this, an embodiment of the present invention provides a data receiving method implemented by a receiving end device, as shown in fig. 9, which may include the following steps:

s91, the MAC layer receives the MAC PDU transmitted by the MAC layer of the transmitting end.

In this step, the MAC layer of the receiving end receives the MAC PDU sent by the MAC layer of the transmitting end through the air interface.

S92, determining the length of the MAC PDU according to the FDF identification value carried in the received MAC PDU.

In specific implementation, the MAC layer may obtain an identification value of FDF from a MAC subheader in the received MAC PDU, determine that the length of the received MAC PDU is 1 if the FDF is 1, determine that the length of the received MAC PDU is greater than 1 if the FDF is 0 or the MAC subheader does not include an FDF field, and accordingly determine the number of the received MAC PDUs because the length of the control PDU is 1 byte, for example, determine that the number of the MAC PDUs is 1 if the length of the MAC PDU is 1, and determine that the number of the MAC PDUs is greater than 1 if the length of the MAC PDU is greater than 1.

If the MAC layer of the receiving end determines that the length of the received MAC PDU is greater than 1, the specific length of the MAC PDU can be determined according to the length field carried by the MAC subheader in the MAC PDU. Firstly, the MAC layer at the receiving end determines whether the length field containing 8 bits or the length field containing 16 bits according to the F field in the MAC subheader, and then further obtains the length of the MAC pdu according to the length of the length field.

S93, the MAC layer analyzes the MAC PDU with corresponding quantity according to the determined length of the MAC PDU to obtain the MAC service data unit SDU.

And S94, the MAC layer sends the obtained MAC SDU to the RLC layer.

In this step, the MAC layer of the receiving end parses the MAC PDU of the corresponding number according to the determined length of the MAC PDU, and constructs a MAC SDU of the corresponding number based on the parsed MAC PDU and transmits the MAC SDU to the RLC layer of the receiving end. Specifically, the MAC layer uses a transparent transmission mode to send the obtained MAC SDU to the radio link control RLC layer by using an uplink dedicated traffic channel UL DTCH and/or a downlink DL DTCH and/or a UL/DL dedicated control channel DCCH, and the MAC SDU is transmitted to the packet data convergence protocol PDCP layer as an RLC PDU and transmitted to the service data adaptation protocol SDAP layer by the RLC layer. The following describes the flow of RLC layer and PDCP transparent transmission control PDU at the receiving end in detail with reference to the accompanying drawings.

S95, the RLC layer of the receiving end transmits the MAC SDU to the PDCP layer.

Specifically, the RLC layer of the receiving end receives the MAC SDU sent by the MAC layer of the receiving end to obtain the RLC PDU, and the RLC layer of the receiving end transmits the obtained RLC PDU to the PDCP layer of the receiving end as the RLC SDU.

S96, the PDCP layer of the receiving end transmits the RLC SDU to the SDAP layer of the receiving end.

Specifically, the PDCP layer of the receiving end obtains the PDCP PDU of the PDCP layer from the RLC SDU, and the PDCP layer of the receiving end transmits the obtained PDCP PDU to the SDAP layer of the receiving end as the PDCP SDU.

S97, the SDAP layer determines the number of PDCP SDUs.

In specific implementation, after receiving the PDCP SDUs transparently transmitted by the PDCP layer, the SDAP layer determines the length of the received PDCP SDUs according to an RRC (radio resource control) signaling and the data length uploaded by the PDCP layer, and parses a corresponding number of PDCP SDUs according to the length of the PDCP SDUs to obtain the SDAP PDU.

In the data receiving method provided in the embodiment of the present invention, the SDAP control PDU may be sent by the MAC CE, and it should be noted that a protocol layer involved in the data receiving method is a protocol layer of a receiving end device.

Based on the same inventive concept, the embodiments of the present invention further provide a data transmitting apparatus and a data receiving apparatus, respectively, and because the principles of the apparatus for solving the problems are similar to the data transmitting method and the data receiving method, respectively, the implementation of the apparatus may refer to the implementation of the method, and repeated details are not repeated.

As shown in fig. 10, which is a schematic structural diagram of a data transmitting apparatus according to an embodiment of the present invention, the data transmitting apparatus includes:

a PDCP unit 101, configured to transparently transmit a PDCP protocol data unit PDU to the RLC unit 102;

the RLC unit 102 is configured to obtain RLC PDUs according to the received PDCP PDUs and pass the RLC PDUs to the MAC unit 103;

the MAC unit 103 is configured to obtain a MAC SDU to be transmitted according to the received RLC PDU, modify an identifier value corresponding to FDF in a subheader of the constructed MAC PDU when the MAC PDU is constructed according to the received MAC SDU if the length of the MAC SDU to be transmitted is 1 byte and the number of the MAC SDU to be transmitted is 1, and send the constructed MAC PDU to the MAC unit 103 of the opposite end.

Optionally, the PDCP unit 101 is configured to receive an SDAP PDU sent by the SDAP unit to obtain a PDCP service data unit SDU; the received PDCP SDUs are transmitted to the RLC unit 102 as PDCP PDUs.

Optionally, the RLC unit 102 is configured to receive an RLC SDU obtained from the PDCP PDU passed through by the PDCP unit 101; taking the RLC SDU as an RLC PDU; RLC PDUs are sent to the MAC unit 103 using a transparent mode on an uplink dedicated traffic channel UL DTCH, and/or a downlink DL DTCH, and/or a UL/DL dedicated control channel DCCH.

Optionally, the MAC unit 103 is configured to select an available bit in a subheader of a MAC PDU to carry the fixed length identifier FDF.

Optionally, the MAC unit 103 is further configured to carry a length field in a subheader of the constructed MAC PDU if the length of the MAC SDU to be transmitted is 1 byte and the number of the MAC SDU to be transmitted is greater than 1, where the length field is used to indicate the length of the MAC PDU.

Optionally, the MAC unit 103 is further configured to modify an identification value corresponding to the FDF in a subheader of the constructed MAC PDU.

Optionally, the MAC unit 103 is configured to determine the number of MAC SDUs to be transmitted according to the same logical control channel identifier LCID.

As shown in fig. 11, which is a schematic structural diagram of a data receiving apparatus according to an embodiment of the present invention, the data receiving apparatus includes:

a MAC unit 111, configured to receive a MAC PDU transmitted by using any one of the data transmission methods; determining the length of the MAC PDU according to the identification value of the fixed length identification FDF carried in the received MAC protocol data unit PDU; analyzing the MAC PDU with corresponding quantity according to the determined length of the MAC PDU to obtain an MAC Service Data Unit (SDU); the obtained MAC SDU is sent to the radio link control RLC unit 112;

the RLC unit 112 is configured to pass through the received mac sdu as an RLC PDU to the packet data convergence protocol PDCP unit 112;

the PDCP unit 113 is configured to pass the received RLC PDU through to a service data adaptation protocol SDAP unit as a PDCP SDU.

Optionally, the MAC unit 111 is configured to send the obtained MAC SDU to the RLC unit 112 by using a transparent transmission mode through an uplink dedicated traffic channel UL DTCH, and/or a downlink DL DTCH, and/or a UL/DL dedicated control channel DCCH;

the RLC unit 112 is configured to receive the MAC SDU sent by the MAC unit 111 to obtain an RLC PDU, and send the RLC PDU to the PDCP unit 113 as an RLC SDU.

Optionally, the PDCP unit 113 is configured to receive an RLC SDU sent by the RLC unit 112 to obtain a PDCP PDU; and sending the PDCP PDU as a PDCP SDU to the SDAP unit.

Optionally, the MAC unit 111 is further configured to determine the length of the MAC PDU according to a length field carried in the MAC PDU if it is determined that the length of the MAC PDU is greater than 1 according to an identifier value of a fixed length identifier FDF carried in the MAC PDU.

Optionally, the SDAP unit is further configured to determine a length of a PDCP SDU after receiving the PDCP SDU transparently transmitted by the PDCP unit 113; and analyzing the corresponding number of PDCP SDUs according to the length of the PDCP SDUs to obtain the SDAP PDU.

For convenience of description, the above parts are separately described as modules (or units) according to functional division. Of course, the functionality of the various modules (or units) may be implemented in the same or in multiple pieces of software or hardware in practicing the invention.

Based on the same technical concept, the embodiment of the present application further provides a communication device, which can implement the data transmission method and/or the data reception method in the foregoing embodiments.

Referring to fig. 12, a schematic structural diagram of a communication device according to an embodiment of the present invention is shown in fig. 12, where the communication device may include: a processor 1201, a memory 1202, a transceiver 1203, and a bus interface.

The processor 1201 is responsible for managing a bus architecture and general processing, and the memory 1202 may store data used by the processor 1201 in performing operations. The transceiver 1203 is configured to receive and transmit data under the control of the processor 1201.

The bus architecture may include any number of interconnected buses and bridges, with one or more processors, represented by the processor 1201, and various circuits, represented by the memory 1202, being linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The processor 1201 is responsible for managing a bus architecture and general processing, and the memory 1202 may store data used by the processor 1201 in performing operations.

The process disclosed by the embodiment of the invention can be applied to the processor 1201, or can be implemented by the processor 1201. In implementation, the steps of the signal processing flow may be implemented by integrated logic circuits of hardware or instructions in the form of software in the processor 1201. The processor 1201 may be a general purpose processor, a digital signal processor, an application specific integrated circuit, a field programmable gate array or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or the like that may implement or perform the methods, steps, and logic blocks disclosed in embodiments of the present invention. A general purpose processor may be a microprocessor or any conventional processor or the like. The steps of a method disclosed in connection with the embodiments of the present invention may be directly implemented by a hardware processor, or may be implemented by a combination of hardware and software modules in the processor. The software module may be located in ram, flash memory, rom, prom, or eprom, registers, etc. storage media as is well known in the art. The storage medium is located in the memory 1202, and the processor 1201 reads information in the memory 1202 and completes the steps of the signal processing flow in conjunction with hardware thereof.

Specifically, the processor 1201 is configured to read a program in a memory and execute any one of the steps of the data transmission method or the data reception method.

Based on the same technical concept, the embodiment of the application also provides a computer storage medium. The computer-readable storage medium stores computer-executable instructions for causing the computer to perform any one of the steps of the aforementioned data transmission method or data reception method.

As will be appreciated by one skilled in the art, embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the invention.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims

1. A data transmission method is characterized in that a service data adaptation protocol SDAP PDU is transmitted through a media access control unit MAC CE, and a subheader of an extended MAC PDU comprises a fixed length identifier FDF; and

the method comprises the following steps:

the MAC layer receives RLC Protocol Data Units (PDU) transmitted by the RLC layer under the control of the wireless link to obtain MAC Service Data Units (SDU) to be transmitted, wherein the RLC PDU is obtained by the RLC layer according to PDCP PDU transmitted by the PDCP layer;

if the length of the MAC SDU to be transmitted is 1 byte and the number is 1, modifying the identification value corresponding to the FDF in the subheader of the MAC PDU when the MAC PDU is established according to the received MAC SDU;

and sending the constructed MAC PDU to the MAC layer of the opposite terminal.

2. The method of claim 1, wherein the PDCP PDUs are obtained according to the following procedure:

and the PDCP layer sends the PDCP SDU to an RLC layer as a PDCP PDU.

3. The method of claim 2, wherein the RLC PDU is obtained according to the following procedure:

the RLC layer takes the RLC SDU as an RLC PDU;

4. The method of claim 1, 2 or 3, wherein extending the MAC PDU subheader to contain the FDF identification comprises:

5. The method of claim 1, 2 or 3, further comprising:

6. The method of claim 5, further comprising:

7. The method of claim 1, 2 or 3, wherein the MAC layer determines the number of MAC SDUs according to the following method:

8. A data receiving method is characterized in that a service data adaptation protocol SDAP PDU is sent through a media access control unit MAC CE, and a subheader of an extended MAC PDU comprises a fixed length identifier FDF; and

the method comprises the following steps:

9. The method of claim 8, wherein the MAC layer sends the obtained MAC SDUs to a radio link control, RLC, layer, which is passed through to a packet data convergence protocol, PDCP, layer as RLC PDUs, comprising:

the RLC layer receives the MAC SDU sent by the MAC layer to obtain an RLC PDU;

and the RLC layer sends the RLC PDU as an RLC SDU to the PDCP layer.

10. The method of claim 9, wherein the PDCP layer passes RLC SDUs to the SDAP layer according to the following procedure:

the PDCP layer receives RLC SDU sent by the RLC layer to obtain PDCP PDU;

the PDCP layer transmits PDCP PDUs as PDCP SDUs to the SDAP layer.

11. The method as claimed in claim 8, 9 or 10, wherein determining the length of the MAC PDU according to the identification value of fixed length identification FDF carried in the MAC PDU comprises:

12. The method of claim 8, 9 or 10, further comprising:

13. A data transmission device is characterized in that a service data adaptation protocol SDAP PDU is transmitted through a media access control unit MAC CE, and a subheader of an extended MAC PDU comprises a fixed length identifier FDF; and

the apparatus, comprising:

14. The apparatus of claim 13,

the PDCP unit is used for receiving the SDAP PDU sent by the SDAP unit to obtain a PDCP service data unit SDU; the received PDCP SDU is transmitted to the RLC unit as a PDCP PDU.

15. The apparatus of claim 14,

the RLC unit is used for receiving RLC SDU obtained by PDCP PDU transmitted by the PDCP unit; taking the RLC SDU as an RLC PDU; the RLC PDUs are sent to the MAC unit using a transparent mode on an uplink dedicated traffic channel UL DTCH, and/or a downlink DL DTCH, and/or a UL/DL dedicated control channel DCCH.

16. The apparatus of claim 13, 14 or 15,

and the MAC unit is used for selecting available bits in a subheader of the MAC PDU to carry the fixed length identifier FDF.

17. The apparatus of claim 13, 14 or 15,

the MAC unit is further configured to carry a length field in a subheader of the constructed MAC PDU if the length of the MAC SDU to be transmitted is 1 byte and the number of the MAC SDU to be transmitted is greater than 1, where the length field is used to indicate the length of the MAC PDU.

18. The apparatus of claim 17,

and the MAC unit is also used for modifying the identification value corresponding to the FDF in the subheader of the constructed MAC PDU.

19. The apparatus of claim 13, 14 or 15,

and the MAC unit is used for determining the number of the MAC SDUs to be transmitted according to the same logic control channel identification (LCID).

20. A data receiving device is characterized in that a media access control unit (MAC CE) sends a Service Data Adaptation Protocol (SDAP) PDU, and a subheader of an extended MAC PDU comprises a fixed length identifier (FDF); and

the apparatus, comprising:

the MAC unit receives the MAC PDU transmitted by the method of any one of claims 1-7; determining the length of the MAC PDU according to the identification value of the fixed length identification FDF carried in the received MAC protocol data unit PDU; analyzing the MAC PDU with corresponding quantity according to the determined length of the MAC PDU to obtain an MAC Service Data Unit (SDU); sending the obtained MAC SDU to a Radio Link Control (RLC) unit;

21. The apparatus of claim 20,

the MAC unit is used for sending the obtained MAC SDU to the RLC unit by utilizing an uplink dedicated traffic channel UL DTCH, and/or a downlink DL DTCH, and/or a UL/DL dedicated control channel DCCH in a transparent transmission mode;

and the RLC unit is used for receiving the MAC SDU sent by the MAC unit to obtain an RLC PDU, and sending the RLC PDU to the PDCP unit as the RLC PDU.

22. The apparatus of claim 21,

the PDCP unit is used for receiving the RLC SDU sent by the RLC unit to obtain a PDCP PDU; and sending the PDCP PDU as a PDCP PDU to the SDAP unit.

23. The apparatus of claim 20, 21 or 22,

the MAC unit is further configured to determine the length of the MAC PDU according to a length field carried in the MAC PDU if the length of the MAC PDU is determined to be greater than 1 according to an identification value of a fixed length identification (FDF) carried in the MAC PDU.

24. The apparatus of claim 20, 21 or 22,

the SDAP unit is further configured to determine a length of the PDCP SDU after receiving the PDCP SDU transparently transmitted by the PDCP unit; and analyzing the corresponding number of PDCP SDUs according to the length of the PDCP SDUs to obtain the SDAP PDU.

25. A communications apparatus, comprising: a processor, a memory, and a transceiver; wherein the memory stores a computer program, and the processor is configured to read the program stored in the memory and execute the method according to any one of claims 1 to 12.

26. A computer storage medium having computer-executable instructions stored thereon for causing a computer to perform the method of any one of claims 1-12.