CN101848489B

CN101848489B - Sending/receiving method and device of PDU (Protocol Data Unit)

Info

Publication number: CN101848489B
Application number: CN200910130308.7A
Authority: CN
Inventors: 王坚
Original assignee: ZTE Corp
Current assignee: Shenzhen Fu Hai Sunshine Technology Co Ltd
Priority date: 2009-03-25
Filing date: 2009-03-25
Publication date: 2014-02-05
Anticipated expiration: 2029-03-25
Also published as: CN101848489A; WO2010108353A1

Abstract

The invention discloses sending/receiving method and device of PDU (Protocol Data Unit), wherein the sending method of the PDU comprises the following steps that an RLC (Radio Link Control) of a sending party receives a plurality of PDUs from a PDCP, and each PDU comprises data information and header information including a sequence number SN; the RLC carries the PDUs in one or more RLC messages, wherein SN of the carried PDU of each RLC message is continuous and each RLC message only carries SN of one PDU; and the RLC sends one or more RLC messages to a receiving party. The invention can reduce occupied system resource in the process of PDU transmission and enhance the transmission efficiency.

Description

PDU transmitting/receiving method and device

Technical Field

The present invention relates to the field of communications, and in particular, to a method and apparatus for transmitting/receiving a Protocol Data Unit (PDU).

Background

Long Term Evolution (LTE) is the latest wireless communication system of the third Generation Partnership Project (3rd Generation Partnership Project, 3GPP) that improves and enhances 3G over-the-air access technology. In LTE, Orthogonal frequency-division multiplexing (OFDM) and Multiple Input Multiple Output (MIMO) are used as basic techniques for wireless network evolution, and main performance targets in LTE include: the peak rate of downlink 100Mbps and uplink 50Mbps is provided in the 20MHz frequency spectrum bandwidth; improving the performance of cell edge users; the cell capacity is improved; reducing system delay; cell coverage of 100km radius is supported; the access service of more than 100kbps can be provided for the high-speed mobile user of 350 km/h; paired or unpaired spectrum is supported, and bandwidth and the like can be flexibly configured.

The LTE air interface protocol (i.e. radio access protocol) mainly includes a User plane protocol and a control plane protocol, and as shown in fig. 1, both exists in a User Equipment (UE) and an evolved NodeB (eNB). In fig. 1, the user side Protocol includes a physical layer (L1), a Media Access Control (MAC) layer, a Radio Link Control (RLC) layer, a Packet Data Convergence Protocol (PDCP) layer, and a network Protocol (IP) layer, where the Control plane Protocol is mainly a Radio Control Protocol. The PDCP is mainly used for compression, ciphering, and integrity protection of data and signaling, each Service data unit (Service data unit, abbreviated as SDU) is associated with a count value, and the count value is used as one of parameters in the compression and decompression of the PDCP and needs to be provided for each PDCP SDU, which wastes a large amount of air interface resources.

In order to reduce the air interface burden, the LTE specification adopts a method that the COUNT value is determined to be 32-bit COUNT, the COUNT is divided into two parts, the high-order part is called Hyper Frame Number (HFN), the low-order part is called PDCP Sequence Number (SN), the HFN is used as a variable, maintenance is performed at both ends of communication, and the PDCP SN is used as a field and exists in a Header (Header) of the PDCP. The PDUs of the PDCP are a Data Radio Bearer (DRB) in Signaling Radio Bearer (SRB) and an Acknowledged Mode (AM) in Acknowledged Mode (AM), and a DRB in Unacknowledged Mode (UM). For SRB, PDCP SN is 5 bits long, plus 3 reserved fields, occupying 1 byte, as shown in fig. 2 a; for UM DRB, the PDCP SN is 7 or 12 bits long, plus the data/control (D/C) identification and reserved field, occupying 2 bytes, as shown in fig. 2 b; for AM DRB, the PDCP SN is 12 bits long, and occupies 2 bytes, plus the D/C identification and reserved fields, as shown in fig. 2C. However, since each PDCP PDU carries a SN, which can be derived from each other, when a large number of PDCP PDUs are transmitted, the redundant transmission method of the PDCP PDUs carrying SNs causes a load on the air interface.

Disclosure of Invention

The present invention is made in view of the problem that load is caused to an air interface due to the fact that each PDCP PDU carries the SN of the PDCP PDU when being transmitted in the related art, and therefore, a main object of the present invention is to provide a PDU transmitting method and a PDU receiving method to solve the above problem in the related art.

According to an aspect of the present invention, there is provided a method of transmitting a PDU.

The method for transmitting the PDU according to the present invention includes: the RLC of the transmitting side receives a plurality of PDUs from the PDCP, wherein each PDU of the plurality of PDUs includes: data information and header information including a SN; the RLC carries the plurality of PDUs in one or more RLC messages, wherein SN of the PDUs carried in each RLC message is continuous, and each RLC message only carries SN of one PDU; and the RLC sends the one or more RLC messages to a receiving party.

According to another aspect of the present invention, there is provided a PDU receiving method.

The method for receiving the PDU according to the present invention includes: the method comprises the following steps that the RLC of a receiving party receives a plurality of continuous RLC messages from a sending party, wherein each RLC message carries the SN of one PDU and at least one PDU, and each PDU comprises: data information and header information not including SN; the RLC analyzes the received plurality of RLC messages, and SN carried in each RLC message, data information of each PDU and header information not including the SN are obtained; the RLC acquires the SN of each PDU carried in each RLC message according to the SN carried in each RLC message; and combining the SN of each PDU into the data information and the header information which does not comprise the SN of the PDU to obtain a PDCP PDU.

According to still another aspect of the present invention, there is provided a PDU transmitting apparatus.

The transmitting apparatus of PDU according to the present invention comprises: the device comprises a receiving module, a configuration module and a sending module. The receiving module is configured to receive a plurality of consecutive PDUs from the PDCP, where each PDU of the plurality of PDUs carries: data information and header information including a SN; the configuration module is used for carrying the plurality of PDUs in one or more RLC messages, wherein SN of the PDUs carried in each RLC message is continuous, and each RLC message only carries SN of one PDU; and the sending module is used for sending the one or more RLC messages to a receiving party.

According to still another aspect of the present invention, there is provided a receiving apparatus of a PDU.

The receiving apparatus of PDU according to the present invention includes: the device comprises a receiving module, an analyzing module, an obtaining module and a combining module. The receiving module is configured to receive multiple consecutive RLC packets from a sender, where each RLC packet carries an SN of one PDU and at least one PDU, where each PDU includes: data information and header information not including SN; the analysis module is used for analyzing the plurality of continuous RLC messages received by the receiving module, and acquiring SN carried in each RLC message, data information of each PDU and header information not including SN; the acquisition module is used for acquiring the SN of each PDU carried in each RLC message according to the analysis result of the analysis module and the SN carried in each RLC message; and the combination module is used for combining the SN of each PDU acquired by the acquisition module into the data information of the PDU and the header information which does not include the SN to acquire one PDCP PDU.

Through the technical scheme of the invention, a plurality of continuous PDCP PDUs are carried in one RLC message, and each RLC message only carries the SN of one PDCP PDU in a plurality of continuous PDCP PDUs, so that the problem that the SN of each PDCP PDU is carried when each PDCP PDU is transmitted in the related technology, and the load is caused to an empty port can be solved, the load caused to the empty port in the process of transmitting the PDCP PDUs can be reduced, the system resources occupied when the PDUs are transmitted are further reduced, and the transmission efficiency of the PDCP PDUs is improved.

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 application, illustrate embodiment(s) of the invention and together with the description serve to explain the invention without limiting the invention. In the drawings:

fig. 1 is a schematic diagram of an LTE radio access network architecture in the related art;

FIG. 2a is a schematic diagram of a related art PDCP PDU being a SRB structure;

FIG. 2b is a schematic diagram of a PDCP PDU being an AM DRB in the related art;

FIG. 2c is a diagram illustrating a structure of a PDCP PDU being an UM DRB in the related art;

fig. 3 is a flowchart of a PDU transmission method according to a first embodiment of the method of the present invention;

fig. 4a is a schematic structural diagram of an RLC packet according to an embodiment of the present invention;

fig. 4b is a schematic structural diagram of another RLC packet according to an embodiment of the method of the present invention;

fig. 5 is a block diagram of a PDU transmitting apparatus according to a first embodiment of the present invention;

fig. 6 is a flowchart of a PDU receiving method according to a second embodiment of the method of the present invention;

fig. 7 is a block diagram of a PDU receiving apparatus according to a second embodiment of the present invention.

Detailed Description

Overview of the function

Considering the problem that the SN of each PDCP PDU is carried when transmitting the PDCP PDU, thereby causing a load to an empty port, the embodiment of the present invention starts from the characteristic that the SNs in consecutive PDCP PDUs are continuously incremented, when a sending side RLC receives a plurality of connected PDUs from a PDCP and transmits the PDUs to the sending side, the RLC carries the PDCP PDUs in one or more RLC messages, wherein for each RLC message, the SN of only one PDCP PDU carried in the RLC message is carried in the RLC message, and for other PDCP PDUs carried in the RLC message, only data information of the PDCP PDUs and header information not including the SNs are carried, and since the PDCP PDUs are consecutive, according to the SNs of the PDCP PDUs carried in the RLC message, the SNs of the other PDCP PDUs carried in the RLC message can be obtained.

It should be noted that, if not conflicting, the embodiments of the present invention and the features of the embodiments may be combined with each other within the scope of protection of the present invention.

Embodiments of the present invention will now be described with reference to the accompanying drawings, and it is to be understood that the preferred embodiments described herein are merely illustrative and explanatory of the invention and are not restrictive thereof. It should be noted that the steps illustrated in the flowcharts of the figures may be performed in a computer system such as a set of computer-executable instructions and that, although a logical order is illustrated in the flowcharts, in some cases, the steps illustrated or described may be performed in an order different than presented herein.

Method embodiment one

According to the embodiment of the invention, a method for transmitting the PDU is provided firstly.

Fig. 3 shows a flow of a PDU sending method according to a first embodiment of the method of the present invention, and as shown in fig. 3, the PDU sending method according to the first embodiment of the method of the present invention mainly includes the following steps (step S302-step S306):

step S302, the RLC of the sender receives a plurality of continuous PDUs from the PDCP, wherein each PDU in the PDUs carries: data information of the PDU and header information including SN of the PDU;

step S304, the RLC carries the PDU in one or more RLC messages, wherein SN of the PDU carried in each RLC message is connected, and each RLC message only carries SN of one PDU;

step S306, the RLC sends the one or more RLC messages to a receiving party.

Preferably, the header of each of one or more RLC messages may carry the length information of the content information of each PDU carried in the RLC message, and the location of the content information of each PDU in the RLC message may be located according to the length information.

After receiving the one or more RLC messages sent by the RLC of the sender, the receiver analyzes the SN of the first PDU and the content information of each PDU carried in each RLC message from the received one or more RLC messages, obtains the SN of each PDU carried in the RLC message according to the SN of the first PDU carried in the RLC message, and combines the content information of each PDU and the corresponding SN thereof.

The details of the above-described processes are further described below.

Step S302

In a specific application, the sender may be both parties of wireless communication, and correspondingly, the receiver may also be both parties of wireless communication, that is, when the sender is a mobile terminal, the receiver is a base station or a relay station, and when the sender is a base station or a relay station, the receiver is a mobile terminal.

When receiving an upper PDCP SDU, the PDCP layer of the sender generates a PDCP SN for the PDCP SDU, and encrypts and integrity-protects the PDCP SDU using the SN as a parameter to generate a PDU, and specifically, encrypting and integrity-protecting the PDCP SDU includes, but is not limited to: encrypting and protecting integrity of SDU carrying signaling, and encrypting and protecting SDU carrying data. Then, the PDCP of the transmitting side transmits a plurality of PDUs, in which SNs of partial PDUs are likely to be consecutive, to the transmitting RLC.

(II) step S304

In a specific application, the RLC carries the plurality of PDUs in one or more RLC messages according to the transmission capacity of the logical channel and SNs of the plurality of PDUs, and specifically, the RLC carries the plurality of PDUs in one or more RLC messages may be implemented by the following steps:

step 1, RLC acquires the transmission capacity C of the current logical channel from the MAC layer;

step 2, RLC judges whether the transmission capacity L of the plurality of PDUs is less than or equal to the transmission capacity C, if yes, step 3 is executed, otherwise step 5 is executed;

the transmission capacity L of the PDUs refers to a capacity of the PDUs after the SNs of the PDUs connected with the SNs are deleted, for example, if the SNs of the PDUs are: 1. 2, 3, 5, 6, 7, the transmission capacity L of these 6 PDUs is: the capacity of the data information of the PDU with SN 1 and the header information including SN, the capacity of the data information of the PDU with SN 2 and the header information not including SN, the capacity of the data information of the PDU with SN 3 and the header information not including SN, the capacity of the data information of the PDU with SN 5 and the header information including SN, the capacity of the data information of the PDU with SN 6 and the header information not including SN, and the capacity of the data information of the PDU with SN 7 and the header information not including SN.

Step 3, the RLC groups the plurality of PDUs according to SNs thereof, wherein the SNs of the PDUs in each group are continuous, and the SNs of the PDUs between the groups are unconnected;

step 4, the RLC carries each group of PDU in an RLC message of the current sub-frame respectively, and step 306 is executed;

and step 5, the RLC carries the plurality of PDUs in one or more RLC messages of at least two subframes.

Specifically, the processing of step 5 above may include the following processing:

step 5.1, sequentially obtaining a data part with transmission capacity of C in the plurality of PDUs, wherein the data part is carried in one or more RLC messages of the current subframe, wherein if there are PDUs with continuous SN in the plurality of PDUs included in the data part, the PDUs connected with SN are carried in one RLC message, so that, similarly, the SNs of the PDUs carried in the one or more RLC messages of the current subframe are continuous, and the SNs of the PDUs carried among the RLC messages are discontinuous, that is, if the SNs of the PDUs included in the data part are continuous, the PDUs of the data part are all carried in one RLC message;

step 5.2, acquiring the transmission capacity E of the current logical channel in the next subframe of the current subframe, judging whether the transmission capacity of the rest data part in the plurality of PDUs is less than or equal to E, if so, executing step 5.3, otherwise, executing step 5.4;

step 5.3, carry the remaining data part in the multiple PDUs in one or more RLC messages of the next subframe of the current subframe, the specific carrying manner is the same as that in step 5.1, which is not described herein again, and step S306 is executed;

step 5.4, sequentially obtaining the data part with the transmission capacity of E of the remaining data part in the plurality of PDUs, and carrying the data part in one or more RLC messages of the next subframe of the current subframe, wherein the specific carrying mode is the same as that in the step 5.1, and is not described herein;

and 5.5, taking the next subframe of the current subframe as the current subframe, and returning to execute the step 5.2.

In a specific application, in the above step 5.3 and step 5.4, for each RLC packet, if a first PDU to be carried in the RLC packet includes data information and header information thereof, that is, the carried first PDU is complete, both the header information and the data information of the PDU are carried in the RLC packet, and data information of other PDUs continuous to the SN of the PDU and header information not including the SN are carried in the RLC packet;

if the first PDU to be carried in the RLC message is not complete, namely only carries partial data of the PDU, carrying partial data contained in the PDU in the RLC message, carrying header information and data information of the next PDU connected with the SN of the PDU in the RLC message, and carrying data information of other PDUs in the RLC message and header information not including the SN in the RLC. In a specific implementation process, under such a condition, the SN carried in the RLC message may also be the SN of the first PDU.

In a specific implementation process, for each RLC packet, the header of the RLC packet may carry length information of each PDU carried in the RLC packet, and the receiving side may analyze each PDU carried in the RLC packet according to the length information.

Fig. 4a shows a structure of an RLC message, as shown in fig. 4a, N PDCP PDUs are carried in Service Data units (Service Data units, abbreviated as SDUs) of N RLC packets except for a header, and each RLC packet only carries an SN of a first PDCP PDU.

Fig. 4b shows another RLC packet structure, as shown in fig. 4b, except for the header, in which only the SN of the second pdcp pdu is carried in the RLC packet.

And, the header of each RLC packet in the one or more RLC packets may further be configured with a first transmission identifier and a second transmission identifier, where the first transmission identifier is used to indicate whether a first PDU carried in the RLC packet is complete, and the second transmission identifier is used to indicate whether a last PDU carried in the RLC packet is complete.

Specifically, a first transmission identifier and a second transmission identifier may be identified by a 2-bit field FI in a header of the RLC packet, where a first bit identifies the first transmission identifier, and when the first bit is 1, it indicates that content information of a first PDU carried in the RLC packet is complete, and when the first bit is 0, it indicates that content information of the first PDU carried in the RLC packet is incomplete; and the second bit identifies a second transmission identifier, indicates that the content information of the last PDU carried in the RLC message is complete when the second bit is 1, and indicates that the content information of the last PDU carried in the RLC message is incomplete when the second bit is 0.

And deleting the SN of the PDCP PDU which does not need to carry the SN in the RLC message. Specifically, the PDCP PDUs are classified into three types, that is, SRBs, AM DRBs, and UM DRBs, so for the three types of PDCP PDUs, a method for carrying data information of the PDCP PDU and header information not including SN in an RLC packet can be specifically distinguished as the following three types: first, as shown in fig. 2a, when a PDCP PDU is an SRB, an SN occupies a byte separately, and the content information of the PDCP PDU may be carried in an RLC packet after the byte is deleted directly; second, in the case that the PDCP PDU is an AMDRB, the SN and a data/control (D/C) flag occupy a byte together, which can be reserved, but the reserved SN does not play a substantial role in recovering the PDCP PDU at the receiving side; thirdly, under the condition that the PDCP PDU is an UM DRB, the length of the SN is 12 bits, the SN and the D/C identifier jointly occupy 2 bytes, the high-order byte including the DC identifier can be reserved, the low-order byte including the SN can be deleted, and the content information of the PDCP PDU after the low-order byte is deleted is carried in an RLC message.

By the technical scheme provided by the embodiment, when a plurality of continuous PDCP PDUs are transmitted, only the SN of the first PDCP PDU carried in the RLC packet is carried, so that the transmission of redundant SN in the process of transmitting the PDUs can be avoided, and the load on an air interface can be reduced.

In the following, taking User Equipment (UE) as an example as a sending end, a specific implementation process of a PDU sending method provided in an embodiment of the present invention is described, specifically, the PDU sending method may include the following steps:

step 1, a PDCP layer of the UE receives a plurality of continuous PDCP PDUs from a non-access layer, the PDCP layer generates a PDCP SN for each PDCP SDU, and the PDCP SN is used for encrypting and integrity protecting each PDCP PDU, specifically encrypting and integrity protecting the PDU carrying signaling and encrypting and protecting the PDU carrying data through the SN;

step 2, the RLC layer receives a plurality of continuous PDCP PDUs which carry SN and are sent by the PDCP layer; step 2 corresponds to the above step S302;

step 3, RLC obtains the transmission capacity C of the current logical channel from the MAC layer;

step 4, judging whether the transmission capacity L of the plurality of PDCP PDUs is less than or equal to the transmission capacity C, if so, executing step 5, otherwise, executing step 7;

step 5, the RLC groups the plurality of PDUs according to SNs thereof, wherein the SNs of the PDUs in each group are continuous, and the SNs of the PDUs between the groups are unconnected;

step 6: the RLC carries each group of PDCP PDUs in an RLC message of the current subframe, and executes the step 13;

step 7, the RLC sequentially obtains the data part with the transmission capacity C in the plurality of PDUs, and the data part is carried in one or more RLC messages of the current subframe;

if there are PDUs with continuous SNs in a plurality of PDUs included in the data portion, the PDUs connected by SNs are carried in one RLC message, so likewise, the SNs of the PDUs carried in one or more RLC messages of the current subframe are continuous, and the SNs of the PDUs carried between the RLC messages are discontinuous, that is, if the SNs of the PDUs included in the data portion are continuous, the PDUs of the data portion are all carried in one RLC message;

step 9, the RLC acquires the transmission capacity E of the current logical channel in the next subframe of the current subframe, and determines whether the transmission capacity E of the remaining data part in the PDUs is less than or equal to E, if so, step 10 is executed, otherwise, step 11 is executed;

step 10, carrying the remaining data part in the plurality of PDUs in one or more RLC messages of the next subframe of the current subframe, and executing step 13;

step 11, sequentially obtaining the data part with the transmission capacity of E of the remaining data part in the plurality of PDUs, and carrying the data part in one or more RLC messages of the next subframe of the current subframe;

step 12, taking the next subframe of the current subframe as the current subframe, and returning to the step 9;

the above-described steps 5 to 12 correspond to the above-described step S304.

Step 13, sending the RLC message to a receiving party (e.g. a base station or a relay station). Step 13 corresponds to step S306 described above.

The processing procedures of steps 1 to 13 may be applied to a scenario where a normal connection has been established between the UE and the base station, and may also be applied to a scenario where the UE performs a base station handover, where the processing procedure may only carry the SN of the first PDCP PDU in the RLC packet when transmitting a plurality of consecutive PDCP PDUs, so as to reduce an air interface load.

Apparatus embodiment one

According to the embodiment of the present invention, a PDU transmitting apparatus is provided, and preferably, the PDU transmitting method provided in the first method embodiment can be used in the apparatus.

Fig. 5 shows a structure of a PDU transmitting apparatus according to an embodiment of the present invention, and as shown in fig. 5, the PDU transmitting apparatus according to the embodiment of the present invention includes: the device comprises a receiving module 1, a configuration module 3 and a sending module 5. The functions of the above modules are further described below.

A receiving module 1, configured to receive a plurality of consecutive PDUs from a PDCP, where each PDU of the plurality of PDUs carries: data information and header information including a sequence number SN; preferably, the receiving module 1 may perform the step S302;

the configuration module 3 is connected to the receiving module 1, and is configured to carry the PDUs received by the receiving module 1 in one or more RLC messages, where SNs of the PDUs carried in each RLC message are continuous, and each RLC message only carries an SN of one PDU; preferably, the configuration module 3 may perform the step S304;

and the sending module 5 is connected to the configuration module 3 and is used for sending one or more RLC messages to the receiving party. Preferably, the sending module 5 may perform the step S306.

By the PDU sending device provided in this embodiment, the RLC packet carrying the SN of only one PDCP PDU can be sent to the receiving side.

Method embodiment two

According to the embodiment of the invention, the invention also provides a PDU receiving method which can be used in cooperation with the PDU sending method.

Fig. 6 shows a flow of a PDU receiving method according to a second embodiment of the method of the present invention, and as shown in fig. 6, the PDU receiving method according to the second embodiment of the method of the present invention mainly includes the following steps (step S602-step S608):

step S602, the RLC of the receiving side receives a plurality of consecutive RLC packets from the sending side, where each RLC packet carries an SN of one PDU and at least one PDU, and each PDU includes: data information and header information not including SN;

step S604, the RLC analyzes the received plurality of RLC messages, and SN carried in each RLC message, data information of each PDU and header information not including SN are obtained;

step S606, the RLC acquires the SN of each PDU carried in each RLC message according to the SN carried in each RLC message;

step S608, combine the SNs of the PUDs into the data information of the PDU and the header information not including the SN to obtain a PDCP PDU.

After the above steps are performed, the RLC of the receiving side may further send each PDCP PDU to the PDCP layer.

Details of the above-described processing are described below.

In step S602, the header of the received RLC packet may further carry length information of each PDU, a first transmission identifier, and a second transmission identifier, where the first transmission identifier is used to indicate whether the first PDU carried in the RLC packet is complete, that is, whether all data information of the PDU and header information that does not include SN are carried, and the second transmission identifier is used to indicate whether the last PDU carried in the RLC packet is complete.

In step S604, preferably, the data information of at least one PDU and the header information that does not include SN may be obtained from the RLC packet according to the length information of each PDU in the RLC packet.

In step S606, for each RLC packet, the SNs of the PDUs before the PDU corresponding to the SN obtained by the parsing are sequentially decreased according to the SN obtained by the parsing, and the SNs after the PDU corresponding to the SN obtained by the parsing are sequentially increased according to the SN obtained by the parsing. .

In step S608, for each RLC packet, the acquired data information and header information of the PDU and the corresponding SN are combined, that is, the SN is written into the header information of the PDU to form a complete PDU.

Furthermore, in step S608, if the first transmission identifier of the current RLC packet indicates that the first PDU in the current RLC packet is not complete (e.g., the first bit of the FI field is 0), the previous RLC packet of the current RLC packet is found according to the SN of the current RLC packet, and if the second transmission identifier of the previous RLC packet indicates that the last PDU carried therein is not complete (e.g., the second bit of the FI field is 0), or if the SN corresponding to the last PDU carried in the previous RLC packet is the same as the SN of the first PDU carried in the current RLC packet, the SN corresponding to the first PDU of the current packet, the data information and the header information (i.e., the first part of data after PDU segmentation) of the first PDU carried in the current packet, the data information and the header information (i.e., the second part of data after PDU segmentation) of the last PDU carried in the current packet are combined, that is, the first part of data and the second part of data are combined to obtain the data information and the header information of the PDU, and the SN is written into the data information and the header information of the combined PDU to obtain the complete PDCP PDU.

By the technical scheme provided by the embodiment, the SN of one PDCP PDU and the data of at least one PDCP PDU can be analyzed and obtained from a plurality of RLC messages from a transmitting party, the SNs corresponding to the other PDCP PDUs are obtained according to the SNs, and the PDCP PDU data and the corresponding SNs are combined to obtain the complete PDCP PDU.

The following specifically describes a specific implementation process of the PDU receiving method according to the second embodiment of the present invention, taking User Equipment (UE) as an example of a receiving end:

step 1, an RLC layer of UE receives an RLC message of an MAC layer; step 1 corresponds to the above step S602;

step 2, the RLC analyzes the RLC message, the SN corresponding to the first PDU is obtained from the RLC message, the length information of the content information of each PDU is obtained from the header of the message, and the first transmission identifier and the second transmission identifier are obtained from the FI word; step 2 corresponds to the above step S604;

step 3, the RLC reads the data information of each PDU and the header information which does not include SN from the RLC message respectively according to the length information of each PDU; step 3 corresponds to the above step S606;

step 4, the RLC judges whether the first bit of the FI field is 1, if so, the processing is carried out to step 5, and if so, the processing is carried out to step 6;

step 5, acquiring the data information and the header information (including SN) of the first PDU carried by the RLC message from the RLC message;

step 6, the RLC combines the content information except the first PDU and the content information except the last PDU and the SN thereof in sequence to obtain a complete PDU;

step 7, the RLC judges whether the second bit of the FI field is 1, if so, the processing proceeds to step 8, and if so, the processing proceeds to step 9;

step 8, RLC combines the data information of the last PDU with the header information not including SN and its corresponding SN to obtain the complete last PDU, and executes step 13;

step 9, the RLC finds the next RLC message according to the SN of the current RLC message;

step 10, judging whether the first bit of the FI field of the next RLC message is 0, if so, processing goes to step 11, otherwise, processing returns to step 9;

step 11, the RLC acquires the data information and the header information of the first PDU from the next RLC message;

step 12, the RLC combines the SN corresponding to the last PDU of the current RLC message, the data of the last PDU and the data of the first PDU in the next RLC message to obtain the complete last PDU; step 4 to step 12 correspond to the above step S608;

and step 13, sending the combined PDU to a PDCP layer. The PDCP layer decrypts and verifies the integrity of the PDCP PDUs according to the received SNs of the PDCP.

Through the processing from the step 1 to the step 13, the SN of one PDCP PDU and the data of at least one PDCP PDU are analyzed and obtained from the plurality of RLC messages from the transmitting side, the SNs corresponding to the remaining PDCP PDUs are obtained according to the SNs, and the data of the PDCP PDUs and the SNs corresponding thereto are combined to obtain complete PDCP PDUs.

Device embodiment II

According to the embodiment of the present invention, a PDU receiving apparatus is provided, which can be used in cooperation with the PDU transmitting apparatus, and can be used for implementing the PDU receiving method provided in the second embodiment of the present invention.

Fig. 7 shows a structure of a PDU receiving apparatus according to a second embodiment of the present invention, and as shown in fig. 7, the PDU receiving apparatus according to the second embodiment of the present invention includes: the device comprises a receiving module 2, an analyzing module 4, an obtaining module 6 and a combining module 8. Wherein,

the receiving module 2 is configured to receive a plurality of consecutive RLC packets from a sender, where each RLC packet carries an SN of one PDU, data information of at least one PDU, and header information that does not include the SN; preferably, the receiving module 2 is configured to execute the step S602;

the analysis module 4 is connected to the receiving module 2 and is used for analyzing the plurality of continuous RLC messages received by the receiving module 2 to obtain SN carried in each RLC message, data information of each PDU and header information not including SN; preferably, the parsing module 4 is configured to perform the step S604;

the acquisition module 6 is connected to the analysis module 4 and used for acquiring SN of each PDU carried in each RLC message according to the result of analysis performed by the analysis module 4 and SN carried in each RLC message; preferably, the obtaining module 6 may be configured to execute the step S606;

and the combination module 8 is connected to the parsing module 4 and the obtaining module 6, and is configured to combine the SN of each PDU obtained by the obtaining module 6 with the data information of each PDU obtained by the parsing module 4 and the header information that does not include the SN to obtain one PDCP PDU. Preferably, the combination module 8 is operable to perform the above step S608.

The PDU receiving apparatus provided in this embodiment can analyze and obtain the SN of one PDCP PDU and the data of at least one PDCP PDU from a plurality of RLC packets from a transmitting party, obtain SNs corresponding to the remaining PDCP PDUs according to the SNs, and combine the PDCP PDU data and the corresponding SNs to obtain a complete PDCP PDU.

It should be noted that, although the sending/receiving method of the PDU is described by taking LTE as an example in the embodiment of the present invention, it should be understood that a person skilled in the art may also apply the sending/receiving method of the PDU provided in the embodiment to other wireless access systems, such as WCDMA, CDMA2000 and TD-SCDMA.

In summary, with the technical solution of the present invention, in the process of carrying a plurality of consecutive PDCP PDUs in an RLC message, only the SN of one PDCP PDU of the plurality of consecutive PDCP PDUs is carried in the RLC message, so that the problem of loading an empty port due to the SN of the PDCP PDU carried in the RLC message when each PDCP PDU is transmitted in the related art can be solved, and the load on the empty port in the process of transmitting the PDCP PDU can be reduced, thereby reducing the occupied system resources and improving the transmission efficiency of the PDCP PDU.

It will be apparent to those skilled in the art that the modules or steps of the present invention described above may be implemented by a general purpose computing device, they may be centralized on a single computing device or distributed across a network of multiple computing devices, and they may alternatively be implemented by program code executable by a computing device, such that they may be stored in a storage device and executed by a computing device, or fabricated separately as individual integrated circuit modules, or fabricated as a single integrated circuit module from multiple modules or steps. Thus, the present invention is not limited to any specific combination of hardware and software.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for sending a pdu, comprising:

a Radio Link Control (RLC) layer of a sender receives a plurality of Protocol Data Units (PDUs) from a Protocol Data Convergence Protocol (PDCP), wherein each PDU of the PDUs comprises: data information and header information including a sequence number SN;

the RLC carries the plurality of PDUs in one or more RLC messages, including: the RLC acquires the transmission capacity C of the current logical channel from a media access layer MAC; if the transmission capacity L of the plurality of PDUs is less than or equal to the transmission capacity C, carrying the plurality of PDUs in one or more RLC messages of a subframe, wherein SN of the PDUs carried in each RLC message is continuous, and SN of the PDUs carried between the RLC messages is discontinuous; if the transmission capacity L is larger than the transmission capacity C, carrying the plurality of PDUs in one or more RLC messages of at least two subframes; c, L is a natural number, the SNs of PDUs carried in each RLC message are continuous, and each RLC message only carries the SN of one PDU;

and the RLC sends the one or more RLC messages to a receiving party.

2. The method of claim 1, further comprising:

and the header of each RLC message in the one or more RLC messages carries the length information of each PDU carried in the RLC message.

3. The method of claim 1, wherein carrying the plurality of PDUs in one or more RLC packets of at least two subframes comprises:

sequentially acquiring data parts with transmission capacity C in the plurality of PDUs and carrying the data parts in one or more RLC messages of the current subframe, wherein SN of the PDUs carried in each RLC message is continuous, and SN of the PDUs carried among the RLC messages is discontinuous;

and sequentially carrying the rest data parts in the plurality of PDUs in one or more RLC messages of the next one or more subframes of the current subframe according to the transmission capacity of the logical channel when the PDUs are transmitted.

4. The method of claim 3, wherein for each RLC packet:

if the first PDU to be carried in the RLC message contains the data information and the header information of the first PDU, carrying the header information and the data information of the first PDU in the RLC message, and carrying the data information of other PDUs continuous with the SN of the first PDU and the header information not containing the SN in the RLC message; or

If the first PDU to be carried in the RLC message only contains partial data in the data information and the header information of the first PDU, carrying the SN of the PDU and the partial data contained in the PDU in the RLC message, and carrying the data information of other PDUs connected with the SN of the PDU and the header information not containing the SN in the RLC message; or

If the first PDU carried in the RLC message only contains partial data in the data information and the header information, carrying the partial data contained in the PDU in the RLC message, carrying the header information and the data information of the next PDU connected with the SN of the PDU in the RLC, and carrying the data information of other PDUs in the RLC message and the header information not including the SN in the RLC.

5. The method according to claim 3 or 4, characterized in that the method further comprises:

and setting a first transmission identifier and a second transmission identifier at the head of each RLC message in the one or more RLC messages, wherein the first transmission identifier is used for indicating whether the first PDU carried in the RLC message is complete, and the second transmission identifier is used for indicating whether the last PDU carried in the RLC message is complete.

6. The method of claim 1, wherein after the RLC sends the one or more RLC packets to a receiving party, the method further comprises:

and carrying the one or more RLC messages in an MAC message, and sending the MAC message to the receiving party.

7. The method of claim 1, wherein after the RLC sends the one or more RLC packets, the method further comprises:

the RLC of the receiving party analyzes SN carried in each RLC message, data information of each PDU and header information not including the SN from the one or more RLC messages, and obtains the SN of each PDU carried in the RLC message according to the SN carried in the RLC message;

for the PDU before the SN, the SN is decreased in sequence according to the position, and for the PDU after the SN, the SN is increased in sequence according to the position.

8. A method for receiving a protocol data unit, comprising:

a Radio Link Control (RLC) layer of a receiving party receives a plurality of continuous RLC messages from a sending party, wherein each RLC message carries a Sequence Number (SN) of a Protocol Data Unit (PDU) and at least one PDU, and each PDU comprises: for each message, the header of the RLC message carries length information of each PDU, a first transmission identifier and a second transmission identifier, wherein the first transmission identifier is used for indicating whether a first PDU carried in the RLC message is complete, and the second transmission identifier is used for indicating whether a last PDU carried in the RLC message is complete;

the RLC analyzes the received plurality of RLC messages, and SN carried in each RLC message, data information of each PDU and header information not including SN are obtained;

the RLC acquires the SN of each PDU carried in each RLC message according to the SN carried in each RLC message;

combining the SN of each PDU into the data information of the PDU and the header information without the SN to obtain a protocol data convergence protocol layer PDCP PDU, comprising: and if the second transmission identifier indicates that the last PDU in the RLC message is not complete and the first transmission identifier of the next message of the RLC message indicates that the first PDU in the message is not complete, acquiring the first PDU from the next message of the RLC message, and combining the SN corresponding to the last PDU in the RLC message, the last PDU in the RLC message and the first PDU in the next message of the RLC message into one PDCP PDU.

9. The method of claim 8, further comprising:

and sending each obtained PDCP PDU to a PDCP layer.

10. The method of claim 8, wherein for each RLC packet, acquiring data information of the PDU carried in the RLC packet and header information that does not include the SN comprises:

and acquiring data information of at least one PDU and header information not including SN from the RLC message according to the length information of each PDU in the RLC message.

11. The method of claim 8, wherein for each RLC packet, obtaining the SN of each PDU comprises:

and sequentially decreasing the SN of each PDU before the PDU corresponding to the SN obtained by analysis according to the SN obtained by analysis, and sequentially increasing the SN behind the PDU corresponding to the SN obtained by analysis according to the SN obtained by analysis.

12. An apparatus for transmitting a protocol data unit, comprising:

a receiving module, configured to receive a plurality of consecutive protocol data units PDUs from a protocol data convergence protocol layer PDCP, where each PDU of the plurality of PDUs carries: data information and header information including a sequence number SN;

a configuration module, configured to carry the PDUs in one or more RLC messages, including: the RLC acquires the transmission capacity C of the current logical channel from a media access layer MAC; if the transmission capacity L of the plurality of PDUs is less than or equal to the transmission capacity C, carrying the plurality of PDUs in one or more RLC messages of a subframe, wherein SN of the PDUs carried in each RLC message is continuous, and SN of the PDUs carried between the RLC messages is discontinuous; if the transmission capacity L is larger than the transmission capacity C, carrying the plurality of PDUs in one or more RLC messages of at least two subframes; c, L is a natural number, the SNs of PDUs carried in each RLC message are continuous, and each RLC message only carries the SN of one PDU;

and the sending module is used for sending the one or more RLC messages to a receiving party.

13. An apparatus for receiving a protocol data unit, comprising:

a receiving module, configured to receive multiple consecutive RLC packets from a sender, where each RLC packet carries a sequence number SN of a protocol data unit PDU and at least one PDU, and each PDU includes: for each message, the header of the RLC message carries length information of each PDU, a first transmission identifier and a second transmission identifier, wherein the first transmission identifier is used for indicating whether a first PDU carried in the RLC message is complete, and the second transmission identifier is used for indicating whether a last PDU carried in the RLC message is complete;

the analysis module is used for analyzing the plurality of continuous RLC messages received by the receiving module to acquire SN carried in each RLC message, data information of each PDU and header information not including SN;

the acquisition module is used for acquiring the SN of each PDU carried in each RLC message according to the analysis result of the analysis module and the SN carried in each RLC message;

the combining module is configured to combine the SN of each PDU acquired by the acquiring module with the data information of the PDU and header information that does not include the SN to obtain a protocol data convergence protocol layer PDCP PDU, and includes: and if the second transmission identifier indicates that the last PDU in the RLC message is not complete and the first transmission identifier of the next message of the RLC message indicates that the first PDU in the message is not complete, acquiring the first PDU from the next message of the RLC message, and combining the SN corresponding to the last PDU in the RLC message, the last PDU in the RLC message and the first PDU in the next message of the RLC message into one PDCP PDU.