CN110012546A - A kind of transmission method, base station and the terminal of protocol Data Unit PDU - Google Patents

Abstract

The present invention provides a method for transmitting protocol data unit PDU, a base station and a terminal. The method includes: determining a first downlink PDU carrying packet header information; the packet header information includes: RQI, identification information of a quality of service flow, and identification information related to the first The sequence number based on the granularity of the quality of service flow corresponding to the downlink PDU; the first downlink PDU is sent to the terminal; the embodiment of the present invention transmits the identification information of the quality of service flow and the quality of service corresponding to the downlink PDU by sending the RQI at the same time. The sequence number of the stream granularity. The terminal indicates whether the terminal has successfully received the RQI through the feedback message. If it is determined that the terminal has successfully received the RQI, it does not need to send the RQI until the next reflection QoS transmission requirement; if it is determined that the terminal has not successfully received the RQI, then The base station needs to retransmit the downlink PDU carrying the packet header information, which can ensure that the terminal successfully receives the RQI, and can also save overhead.

Description

A kind of protocol data unit PDU transmission method, base station and terminal

technical field

The present invention relates to the field of communication technologies, and in particular, to a method for transmitting a protocol data unit PDU, a base station and a terminal.

Background technique

According to the latest progress of 3GPP RAN2, it is determined to add a new access sublayer, ie, the SDAP (Service Data Aggregation Protocol) layer, above the PDCP (Packet Data Convergence Protocol, Packet Data Convergence Protocol) layer. The SDAP layer is mainly responsible for the mapping of QoS Flow (Quality of Service Flow) to DRB (Data Radio Bearer), and marks different QoS Flow IDs (Quality of Service Flow Identifiers). Currently, 3GPP RAN2 discusses the need to support Reflective QoS (Reflective Quality of Service) functionality at the SDAP layer. Reflective QoS intends to instruct the terminal to use the same mapping method in the uplink by carrying the RQI (Reflective QoS Indicator, reflective quality of service indicator) in the downlink SDAP data packet header, thereby realizing fast remapping of QoS Flow to DRB.

Regarding the Reflective QoS function, 3GPP RAN2 currently believes that after the remapping is successful, it is no longer necessary to carry packet headers when transmitting downlink SDAP PDUs (SDAP Protocol Data Units), thereby saving header overhead.

In order to ensure that the downlink data packets with Reflective QoS information can be successfully received by the terminal and save the header overhead, 3GPP RAN2 currently proposes two packet header carrying methods for discussion:

1. Only carry the header in the first SDAP PDU to indicate that the terminal needs to perform the Reflective QoS function;

2. Carry header indications in the first SDAP PDUs.

However, for these two implementations, the functions of the current SDAP layer cannot ensure that the SDAP PDU carrying the Reflective QoS header can be successfully received by the terminal.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a protocol data unit PDU transmission method, a base station and a terminal, so as to solve the problem in the prior art that the base station cannot ensure that the PDU carrying the RQI can be successfully received by the terminal.

In order to solve the above problem, an embodiment of the present invention provides a method for transmitting a protocol data unit PDU, which is applied to the base station side, including:

Determine the first downlink protocol data unit PDU carrying packet header information; wherein, the packet header information includes: the reflected service quality indicator RQI, the identification information of the quality of service flow in the current downlink transmission, and the corresponding first downlink PDU. The sequence number of the quality of service flow granularity; the RQI is used to indicate that the mapping relationship between the quality of service flow and the data radio bearer in downlink transmission is suitable for uplink transmission;

Send the first downlink PDU carrying packet header information to the terminal.

Wherein, after the step of sending the first downlink PDU carrying packet header information to the terminal, the transmission method further includes:

The first feedback message sent by the terminal is received within the first preset time length, and it is determined that the terminal successfully receives the RQI; wherein, the first feedback message carries the identification information of the quality of service flow and the information related to the the sequence number based on the QoS flow granularity corresponding to the first downlink PDU;

If the first feedback message sent by the terminal is not received within the first preset time length, it is determined that the terminal has not successfully received the RQI.

Wherein, after the step of sending the first downlink PDU carrying packet header information to the terminal, the transmission method further includes:

The second feedback message sent by the terminal is received within the second preset time length; if the second feedback message carries the identification information of the quality of service flow, and the quality of service-based service corresponding to the first downlink PDU is carried in the second feedback message The sequence number of the flow granularity and the confirmation ACK character determine that the terminal successfully receives the RQI; if the second feedback message carries the identification information of the quality of service flow, the service-based The sequence number of the mass flow granularity and the unacknowledged NACK character, to determine that the terminal has not successfully received the RQI;

If the second feedback message sent by the terminal is not received within the second preset time length, it is determined that the terminal fails to receive the RQI successfully.

Wherein, after the step of determining that the terminal fails to receive the RQI, the method further includes:

sending the second downlink PDU carrying the packet header information to the terminal;

After the step of determining that the terminal successfully receives the RQI, the method further includes:

Send a third downlink PDU that does not carry the packet header information to the terminal.

Wherein, when the second downlink PDU carrying the packet header information is sent to the terminal, if the identification information of the quality of service flow included in the packet header information of the second downlink PDU is different from the packet header information of the first downlink PDU If the identification information of the included quality of service flows is the same, the sequence number included in the packet header information of the second downlink PDU is equal to the sum of the sequence number included in the packet header information of the first downlink PDU and a preset value.

Wherein, the step of receiving the first feedback message sent by the terminal within the first preset time length includes;

The uplink control PDU sent by the terminal is received within a first preset time length; wherein, the uplink control PDU carries the first feedback message; or,

The uplink data PDU sent by the terminal is received within the first preset time length; wherein, the packet header of the uplink data PDU carries the first feedback message.

Wherein, the step of receiving the second feedback message sent by the terminal within the second preset time length includes:

The uplink control PDU sent by the terminal is received within the second preset time length; wherein, the uplink control PDU carries the second feedback message; or,

The uplink data PDU sent by the terminal is received within the second preset time length, wherein the packet header of the uplink data PDU carries the second feedback message.

The embodiment of the present invention also provides a method for transmitting a protocol data unit PDU, which is applied to the terminal side, including:

Receive the first downlink protocol data unit PDU that carries packet header information and is sent by the base station; wherein the packet header information includes: the reflected service quality indicator RQI, the identification information of the quality of service flow in the current downlink transmission, and the first downlink PDU. The corresponding sequence number based on the granularity of the quality of service flow; the RQI is used to indicate that the mapping relationship between the quality of service flow and the data radio bearer in the downlink transmission is applicable to the uplink transmission;

Parse the first downlink PDU to determine whether the RQI is successfully received.

Wherein, after the step of parsing the first downlink PDU and determining whether the RQI is successfully received, the method further includes:

If the terminal successfully receives the RQI, it sends a first feedback message to the base station within a first preset time length; wherein, the first feedback message carries the identification information of the quality of service flow and the first downlink PDU. Corresponding sequence number based on QoS flow granularity;

If the terminal fails to receive the RQI, the terminal does not send the first feedback message to the base station within the first preset time length.

Wherein, after the step of parsing the first downlink PDU and determining whether the RQI is successfully received, the method further includes:

Send a second feedback message to the base station within a second preset time length; wherein, the second feedback message carries the identification information of the quality of service flow, the quality of service flow granularity-based identification information corresponding to the first downlink PDU sequence number and confirmation ACK character; or, the second feedback message carries the identification information of the quality of service flow, the sequence number based on the granularity of the quality of service flow corresponding to the first downlink PDU, and the unacknowledged NACK character;

Alternatively, the second feedback message is not sent to the base station within the second preset time length.

Wherein, the transmission method further includes:

receiving the second downlink PDU that is sent by the base station and that carries the packet header information; or,

A third downlink PDU that does not carry the packet header information and is sent by the base station is received.

Wherein, the step of sending the first feedback message to the base station within the first preset time length includes:

Send an uplink control PDU to the base station within a first preset time length; wherein, the uplink control PDU carries the first feedback message; or,

Send the uplink data PDU to the base station within a first preset time length; wherein, the packet header of the uplink data PDU carries the first feedback message.

Wherein, the step of sending the second feedback message to the base station within the second preset time length includes:

Send an uplink control PDU to the base station within a second preset time length; wherein, the uplink control PDU carries the second feedback message; or,

If the uplink data PDU is sent to the base station within the second preset time length; wherein, the packet header of the uplink data PDU carries the second feedback message.

An embodiment of the present invention further provides a base station, including a processor and a transceiver, where the processor is configured to perform the following processes:

Determine the first downlink protocol data unit PDU carrying packet header information; wherein, the packet header information includes: the reflected service quality indicator RQI, the identification information of the quality of service flow in the current downlink transmission, and the corresponding first downlink PDU. The sequence number of the quality of service flow granularity; the RQI is used to indicate that the mapping relationship between the quality of service flow and the data radio bearer in downlink transmission is suitable for uplink transmission;

The transceiver is used to perform the following processes:

Send the first downlink PDU carrying packet header information to the terminal.

Wherein, the processor is used to perform the following process:

The first feedback message sent by the terminal is received within the first preset time length, and it is determined that the terminal successfully receives the RQI; wherein, the first feedback message carries the identification information of the quality of service flow and the information related to the the sequence number based on the QoS flow granularity corresponding to the first downlink PDU;

If the first feedback message sent by the terminal is not received within the first preset time length, it is determined that the terminal has not successfully received the RQI.

Wherein, the processor is used to perform the following process:

The second feedback message sent by the terminal is received within the second preset time length; if the second feedback message carries the identification information of the quality of service flow, and the quality of service-based service corresponding to the first downlink PDU is carried in the second feedback message The sequence number of the flow granularity and the confirmation ACK character determine that the terminal successfully receives the RQI; if the second feedback message carries the identification information of the quality of service flow, the service-based The sequence number of the mass flow granularity and the unacknowledged NACK character, to determine that the terminal has not successfully received the RQI;

If the second feedback message sent by the terminal is not received within the second preset time length, it is determined that the terminal fails to receive the RQI successfully.

Wherein, the transceiver is also used for:

sending the second downlink PDU carrying the packet header information to the terminal; or,

Send a third downlink PDU that does not carry the packet header information to the terminal.

Wherein, when the second downlink PDU carrying the packet header information is sent to the terminal, if the identification information of the quality of service flow included in the packet header information of the second downlink PDU is different from the packet header information of the first downlink PDU If the identification information of the included quality of service flows is the same, the sequence number included in the packet header information of the second downlink PDU is equal to the sum of the sequence number included in the packet header information of the first downlink PDU and a preset value.

Wherein, the transceiver is also used for:

The uplink control PDU sent by the terminal is received within a first preset time length; wherein, the uplink control PDU carries the first feedback message; or,

The uplink data PDU sent by the terminal is received within the first preset time length; wherein, the packet header of the uplink data PDU carries the first feedback message.

Wherein, the transceiver is also used for:

The uplink control PDU sent by the terminal is received within the second preset time length; wherein, the uplink control PDU carries the second feedback message; or,

The uplink data PDU sent by the terminal is received within the second preset time length, wherein the packet header of the uplink data PDU carries the second feedback message.

An embodiment of the present invention further provides a terminal, including a processor and a transceiver, where the transceiver is configured to perform the following processes:

Receive the first downlink protocol data unit PDU that carries packet header information and is sent by the base station; wherein the packet header information includes: the reflected service quality indicator RQI, the identification information of the quality of service flow in the current downlink transmission, and the first downlink PDU. The corresponding sequence number based on the granularity of the quality of service flow; the RQI is used to indicate that the mapping relationship between the quality of service flow and the data radio bearer in the downlink transmission is applicable to the uplink transmission;

The processor is configured to perform the following processes:

Parse the first downlink PDU to determine whether the RQI is successfully received.

Wherein, the transceiver is also used for:

If the terminal successfully receives the RQI, it sends a first feedback message to the base station within a first preset time length; wherein, the first feedback message carries the identification information of the quality of service flow and the first downlink PDU. Corresponding sequence number based on QoS flow granularity;

If the terminal fails to receive the RQI, the terminal does not send the first feedback message to the base station within the first preset time length.

Wherein, the transceiver is also used for:

Send a second feedback message to the base station within a second preset time length; wherein, the second feedback message carries the identification information of the quality of service flow, the quality of service flow granularity-based identification information corresponding to the first downlink PDU sequence number and confirmation ACK character; or, the second feedback message carries the identification information of the quality of service flow, the sequence number based on the granularity of the quality of service flow corresponding to the first downlink PDU, and the unacknowledged NACK character;

Alternatively, the second feedback message is not sent to the base station within the second preset time length.

Wherein, the transceiver is also used for:

receiving the second downlink PDU that is sent by the base station and that carries the packet header information; or,

A third downlink PDU that does not carry the packet header information and is sent by the base station is received.

Wherein, the transceiver is also used for:

Send an uplink control PDU to the base station within a first preset time length; wherein, the uplink control PDU carries the first feedback message; or,

Send the uplink data PDU to the base station within a first preset time length; wherein, the packet header of the uplink data PDU carries the first feedback message.

Wherein, the transceiver is also used for:

Send an uplink control PDU to the base station within a second preset time length; wherein, the uplink control PDU carries the second feedback message; or,

If the uplink data PDU is sent to the base station within the second preset time length; wherein, the packet header of the uplink data PDU carries the second feedback message.

An embodiment of the present invention also provides a communication device, including a memory, a processor, and a computer program stored on the memory and running on the processor, where the processor implements the above-mentioned program when executing the program A protocol data unit PDU transmission method; or, when the processor executes the program, the above-mentioned protocol data unit PDU transmission method is implemented.

Embodiments of the present invention further provide a computer-readable storage medium on which a computer program is stored, and when the program is executed by a processor, implements the steps in the above-mentioned method for transmitting a protocol data unit PDU; or, the program is processed The steps in the protocol data unit PDU transmission method as described above are implemented when the processor executes.

In the above technical solution of the embodiment of the present invention, by sending the identification information of the quality of service flow and the sequence number based on the granularity of the quality of service flow corresponding to the downlink PDU while sending the RQI, when the terminal successfully receives the downlink PUD carrying the packet header information It is necessary to send a feedback message to the base station to indicate whether the terminal has successfully received the RQI through the feedback message. If the base station determines that the terminal has successfully received the RQI, there is no need to send the RQI until the next reflection QoS transmission is required; if the base station determines that the terminal has not successfully received the RQI , the base station needs to retransmit the downlink PDU carrying the packet header information; the transmission method provided by the embodiment of the present invention can ensure that the terminal successfully receives the RQI, and can also save overhead.

Description of drawings

1 shows one of the flow charts of the steps of a method for transmitting a protocol data unit PDU provided by an embodiment of the present invention;

2 shows a schematic structural diagram of an uplink control PDU in a method for transmitting a protocol data unit PDU according to an embodiment of the present invention;

FIG. 3 shows the second flow chart of the steps of a method for transmitting a protocol data unit PDU provided by an embodiment of the present invention;

FIG. 4 shows a schematic structural diagram of a base station provided by an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of a terminal provided by an embodiment of the present invention.

Detailed ways

In order to make the technical problems, technical solutions and advantages to be solved by the present invention more clear, the following will be described in detail with reference to the accompanying drawings and specific embodiments.

As shown in FIG. 1 , an embodiment of the present invention provides a method for transmitting a protocol data unit (PDU), which is applied to the base station side. Specifically, the transmission method is applied to the SDAP (Service Data Aggregation Protocol, Service Data Aggregation Protocol) layer of the base station side. . The transmission method includes:

Step 11: Determine the first downlink protocol data unit PDU carrying packet header information; wherein, the packet header information includes: the reflected service quality indicator RQI, the identification information of the quality of service flow in the current downlink transmission, and the first downlink PDU. Corresponding sequence number based on QoS flow granularity;

Wherein, the RQI is used to indicate that the mapping relationship between the quality of service flow and the data radio bearer in downlink transmission is suitable for uplink transmission.

Specifically, when the reflective QoS function needs to be used for remapping, and there is downlink data that needs to be transmitted, the base station side will perform the above step 11 only.

Step 12: Send the first downlink PDU carrying packet header information to the terminal.

In the above embodiments of the present invention, the RQI specifically refers to the Reflective QoS Indicator, that is, the Reflective QoS Indicator. The RQI is used to indicate that the mapping relationship between the QoS flow in downlink transmission and the data radio bearer DRB is suitable for uplink transmission. For example, the QoS flow 1 in the current downlink transmission is mapped to the DRB1, and the header information of the first downlink PDU sent by the base station to the terminal includes: RQI, the identification information of the QoS flow 1, and the base-based information corresponding to the first downlink PDU. Sequence number of QoS flow 1. In short, the granularity of sequence numbers (also called SN numbers) is based on each QoS flow.

Preferably, the length of the serial number is variable, and the base station can determine one or more length options of the serial number according to the requirements of the network transmission rate.

To sum up, in the above-mentioned embodiments of the present invention, after the terminal successfully receives the first downlink PDU sent by the base station that carries the header information, it needs to send a feedback message to the base station to inform the base station that it has successfully received the RQI, and the base station does not need to send the packet header any more. The downlink PDU of the information; this method can not only ensure that the terminal successfully receives the RQI, but also can save the overhead.

Further, in the above embodiment of the present invention, after step 12, the transmission method further includes:

Step 13: The first feedback message sent by the terminal is received within a first preset time length, and it is determined that the terminal successfully receives the RQI; wherein, the first feedback message carries the identification information of the quality of service flow and a sequence number based on the QoS flow granularity corresponding to the first downlink PDU;

Step 14: The first feedback message sent by the terminal is not received within a first preset time length, and it is determined that the terminal has not successfully received the RQI.

Or, after step 12, the transmission method further includes:

Step 15, the second feedback message sent by the terminal is received within the second preset time length; It is determined that the terminal successfully receives the RQI based on the sequence number of the QoS flow granularity and the acknowledgment ACK character; if the second feedback message carries the identification information of the QoS flow, which corresponds to the first downlink PDU The sequence number based on the quality of service flow granularity and the unacknowledged NACK character, determine that the terminal fails to receive the RQI;

Step 16: The second feedback message sent by the terminal is not received within the second preset time length, and it is determined that the terminal has not successfully received the RQI.

In short, within the preset time length (the first preset time length and the second preset time length), the terminal can directly or indirectly indicate whether the terminal is successful by whether it is sending a feedback message and what kind of information is carried in the feedback message. Receive RQI.

It should be noted that if the terminal does not receive the downlink PDU sent by the base station (transmission interruption occurs due to some reasons), the terminal cannot give any feedback message, and the base station sends the first downlink PDU carrying the header information in the first downlink PDU. No feedback message sent by the terminal is received within a preset time length or within a second preset time length, and the base station also assumes that the terminal fails to receive the RQI. Specifically, the first preset time length and the second preset time length may or may not be equal, which are not specifically limited herein.

Specifically, the first preset time length or the second preset time length may be implemented by a timer, that is, the base station starts the timer every time a new downlink PDU carrying packet header information is sent, and the timing length of the timer is The above-mentioned first preset time length or second preset time length. The timer is also for the quality of service flow, and for each quality of service flow, only one timer runs at most at the same time.

It should be noted that, after the sequence number is introduced at the base station side, the SDAP layer at the base station side introduces two state variables. For example, the above two state variables are respectively: the SN number (next_transmitted_SN) corresponding to the next PDU to be sent and the SN number (first_unconfirmed_SN) corresponding to the first PDU that has not yet received feedback.

Specifically, next_transmitted_SN is used to indicate the SN number corresponding to the next PDU that needs to carry header information, and the initial value of this state variable can be set to 0; first_unconfirmed_SN is used to indicate that the first PDU that has not yet received feedback that carries header information corresponds to SN number, in other words, first_unconfirmed_SN is used to indicate the SN number corresponding to the currently sent PDU carrying packet header information, and its initial value can also be set to 0. It should be noted that the granularity of the above two state variables is also based on each QoS flow.

After the base station receives the first feedback message or the second feedback message from the terminal, in order to confirm whether the sequence number carried in the first feedback message or the second feedback message is the same as the sequence number carried in the first downlink PDU sent by the base station, the base station may Compare the sequence number obtained by parsing the first feedback message or the second feedback message with the current value of first_unconfirmed_SN, and if they are consistent, determine the sequence number carried in the first feedback message or the second feedback message and the first downlink PDU sent by the base station. The serial number carried in is the same. When the base station determines that the RQI has not been successfully received, the base station needs to re-send the second PDU carrying the packet header information to the terminal (that is, to implement retransmission). At this time, the SN number contained in the packet header information in the second PDU is next_transmitted_SN. Configure the SN number corresponding to the next PDU to be sent, thereby improving the efficiency of retransmission.

It should be further noted that, after the step of determining that the terminal fails to receive the RQI, the method further includes:

Send the second downlink PDU carrying the packet header information to the terminal.

Specifically, when the timer expires, the base station retransmits the second downlink PDU carrying the packet header information to the terminal, and the packet header information of the second downlink PDU includes the reflected service quality indicator RQI and the identifier of the quality of service flow in the current downlink transmission. information and the QoS flow granularity-based sequence number corresponding to the second downstream PDU.

It should be noted that when the second downlink PDU carrying the packet header information is sent to the terminal, if the identification information of the quality of service flow included in the packet header information of the second downlink PDU is the same as that of the first downlink PDU. The identification information of the quality of service flow included in the packet header information is the same, then the sequence number included in the packet header information of the second downlink PDU is equal to the sequence number included in the packet header information of the first downlink PDU and a preset value. and.

If the identification information of the quality of service flow contained in the packet header information of the second downlink PDU is different from the identification information of the quality of service flow contained in the packet header information of the first downlink PDU, the packet header information of the second downlink PDU contains the identification information of the quality of service flow. The sequence number has nothing to do with the sequence number included in the header information of the first downlink PDU; it will not be described in detail here.

Specifically, if the sequence numbers corresponding to the downlink PDUs carrying the identification information of the same quality of service flow may be increased in a sequential manner.

For example, if the preset value is equal to 1, the base station starts a timer when sending the first PDU carrying packet header information (ie, the first downlink PDU); wherein, the packet header information of the first PDU carrying packet header information includes: RQI , QoS flow 1, and sequence number 0. If the terminal fails to receive the RQI, the base station resends the second PDU (ie the second downlink PDU) carrying the header information after the timer expires or after determining that the terminal has not successfully received the RQI, wherein the second PDU carrying the header information The header information of the PDU includes: RQI, QoS flow 1 and sequence number 1.

It should be noted that, between the time when the base station sends the first downlink PDU and determines that the terminal fails to receive the RQI, the base station may also send a PDU carrying header information to the terminal. The serial number carried can be the same as the serial number carried in the header information of the first downlink PDU, or the serial number carried in the packet header information can be added with a preset value (which can be added each time a PDU carrying the packet header information is sent). 1). It should be further noted that, in this case, the base station determines that the sequence number carried in the header information of the PDU carrying the header information and sent to the terminal after the terminal fails to receive the RQI is a downlink PDU that is closest to the PDU in the time domain. The sum of the serial number carried in the packet header information and the preset value. For example, if the preset value is equal to 1, the base station starts the timer when sending the first PDU carrying packet header information; wherein, the packet header information of the first PDU carrying packet header information includes: RQI, QoS flow 1 and sequence number 0; Before the base station determines that the terminal has not successfully received the RQI, the base station also sends a second PDU carrying header information. At this time, the packet header information of the second PDU carrying the packet header information includes: RQI, QoS flow 1 and sequence number 1; the base station After sending the second PDU carrying header information, it is confirmed that the terminal has not successfully received the RQI. At this time, the base station needs to retransmit the PDU carrying the header information. At this time, the header information of the PDU includes: RQI, QoS flow 1 and sequence number 2. Not enumerated here.

It should be further noted that if the number of retransmissions of downlink PDUs carrying packet header information exceeds the maximum number of retransmissions, an error will be reported to the upper layer to avoid consistent repeated transmission and transmission failure, wasting resources; reporting errors in time can also improve maintenance efficiency.

After the step of determining that the terminal successfully receives the RQI, the method further includes:

Send a third downlink PDU that does not carry the packet header information to the terminal; until there is a transmission requirement for the next reflection quality of service.

If the terminal successfully receives the RQI, it indicates that the terminal can realize fast remapping of the quality of service flow to the DRB during uplink transmission. and the sequence number based on the QoS flow granularity corresponding to the first downlink PDU, thereby saving overhead.

Further, in the above-mentioned embodiment of the present invention, the step of receiving the first feedback message sent by the terminal within the first preset time length includes;

The uplink control PDU sent by the terminal is received within a first preset time length; wherein, the uplink control PDU carries the first feedback message; or,

The uplink data PDU sent by the terminal is received within the first preset time length; wherein, the packet header of the uplink data PDU carries the first feedback message.

The step of receiving the second feedback message sent by the terminal within the second preset time length includes:

The uplink control PDU sent by the terminal is received within the second preset time length; wherein, the uplink control PDU carries the second feedback message; or,

The uplink data PDU sent by the terminal is received within the second preset time length, wherein the packet header of the uplink data PDU carries the second feedback message.

Preferably, there are two options for the design of the above-mentioned upstream PDU:

Option 1: when the uplink PDU is an uplink control PDU, the uplink control PDU carries the first feedback message or the second feedback message. The uplink control PDU is used to specifically indicate the sequence number carried in the downlink PDU received by the terminal. In this case, the uplink data PDU does not need to carry the serial number. In order to make a compromise between reliability and cost saving, one or more of the above-mentioned uplink control PDUs may be sent within a period of time, which is not specifically limited here.

Figure 2 shows one of the possible structures of the 8-bit uplink control PDU in option 1. Specifically, the uplink control PDU includes:

QoS Flow ID: QoS Flow ID is used to distinguish different QoS Flows mapped to the same DRB; and,

The ACK_SN field is used to indicate the sequence number carried in the downlink PDU corresponding to this feedback;

Optionally, the uplink control PDU further includes:

The D/C field is used to indicate whether a data PDU or a control PDU is being sent; and/or,

The CPT field is used to indicate the type of control PDU.

Option 2: When the uplink PDU is an uplink data PDU, the data packet header of the uplink data PDU carries the first feedback message or the second feedback message. By carrying the sequence number in the uplink data PDU to implicitly indicate that the RQI carried in the downlink PDU has been successfully received, this option requires adding the SN field to the data packet header of the uplink data PDU, and the SN field is used to indicate the corresponding downlink PDU. carried serial number.

To sum up, in the above-mentioned embodiments of the present invention, by sending the identification information of the quality of service flow and the sequence number based on the granularity of the quality of service flow corresponding to the downlink PDU while sending the RQI, when the terminal successfully receives the downlink PUD carrying the packet header information It is necessary to send a feedback message to the base station to indicate whether the terminal has successfully received the RQI through the feedback message. If the base station determines that the terminal has successfully received the RQI, there is no need to send the RQI until the next reflection QoS transmission is required; if the base station determines that the terminal has not successfully received the RQI , the base station needs to retransmit the downlink PDU carrying the packet header information; the transmission method provided by the embodiment of the present invention can ensure that the terminal successfully receives the RQI, and can also save overhead.

As shown in FIG. 3 , an embodiment of the present invention further provides a method for transmitting a protocol data unit PDU, which is applied to the terminal side, including:

Step 31: Receive the first downlink protocol data unit PDU carrying packet header information sent by the base station; wherein, the packet header information includes: the reflected service quality indicator RQI, the identification information of the quality of service flow in the current downlink transmission, and the first The sequence number based on the quality of service flow granularity corresponding to the downlink PDU;

Wherein, the RQI is used to indicate that the mapping relationship between the quality of service flow and the data radio bearer in downlink transmission is suitable for uplink transmission.

Step 32: Parse the first downlink PDU to determine whether the RQI is successfully received.

In the above embodiments of the present invention, the RQI specifically refers to the Reflective QoS Indicator, that is, the Reflective QoS Indicator. The RQI is used to indicate that the mapping relationship between the QoS flow in downlink transmission and the data radio bearer DRB is suitable for uplink transmission. For example, the QoS flow 1 in the current downlink transmission is mapped to the DRB1, and the header information of the first downlink PDU sent by the base station to the terminal includes: RQI, the identification information of the QoS flow 1, and the base-based information corresponding to the first downlink PDU. Sequence number of QoS flow 1. In short, the granularity of sequence numbers (also called SN numbers) is based on each QoS flow.

Preferably, the length of the serial number is variable, and the base station can determine one or more length options of the serial number according to the requirements of the network transmission rate.

To sum up, in the above-mentioned embodiments of the present invention, after the terminal successfully receives the first downlink PDU sent by the base station that carries the header information, it needs to send a feedback message to the base station to inform the base station that it has successfully received the RQI, and the base station does not need to send the packet header any more. The downlink PDU of the information; this method can not only ensure that the terminal successfully receives the RQI, but also can save the overhead.

Further, after step 32 in the above embodiment of the present invention, the method further includes:

Step 33, if the terminal successfully receives the RQI, sends a first feedback message to the base station within a first preset time length; wherein, the first feedback message carries the identification information of the quality of service flow and the first feedback message. The sequence number based on the quality of service flow granularity corresponding to the downlink PDU;

Step 34: If the terminal fails to receive the RQI, the terminal does not send the first feedback message to the base station within the first preset time length.

Or, after step 32, the transmission method further includes:

Step 35: Send a second feedback message to the base station within a second preset time length; wherein, the second feedback message carries the identification information of the quality of service flow and the quality of service-based service corresponding to the first downlink PDU. The sequence number of the flow granularity and the confirmation ACK character; or, the second feedback message carries the identification information of the quality of service flow, the sequence number based on the granularity of the quality of service flow corresponding to the first downlink PDU, and the unacknowledged NACK character;

Or, in step 36, the second feedback message is not sent to the base station within the second preset time length.

In short, within the preset time length (the first preset time length and the second preset time length), the terminal can directly or indirectly indicate whether the terminal is successful by whether it is sending a feedback message and what kind of information is carried in the feedback message. Receive RQI.

It should be noted that if the terminal does not receive the downlink PDU sent by the base station (transmission interruption occurs due to some reasons), the terminal cannot give any feedback message, and the base station sends the first downlink PDU carrying the header information in the first downlink PDU. No feedback message sent by the terminal is received within a preset time length or within a second preset time length, and the base station also assumes that the terminal fails to receive the RQI. Specifically, the first preset time length and the second preset time length may or may not be equal, which are not specifically limited herein.

Specifically, the first preset time length or the second preset time length may be implemented by a timer, that is, the base station starts the timer every time a new downlink PDU carrying packet header information is sent, and the timing length of the timer is The above-mentioned first preset time length or second preset time length. The timer is also for the quality of service flow, and for each quality of service flow, only one timer runs at most at the same time.

Further, the transmission method described in the above-mentioned embodiment of the present invention further includes:

receiving the second downlink PDU that is sent by the base station and that carries the packet header information; or,

Receive the third downlink PDU sent by the base station that does not carry the packet header information; until there is a transmission requirement for the next reflection service quality.

Specifically, when the timer expires, the base station retransmits the second downlink PDU carrying the packet header information to the terminal, and the packet header information of the second downlink PDU includes the reflected service quality indicator RQI and the identifier of the quality of service flow in the current downlink transmission. information and the QoS flow granularity-based sequence number corresponding to the second downstream PDU.

It should be noted that when the second downlink PDU carrying the packet header information is sent to the terminal, if the identification information of the quality of service flow included in the packet header information of the second downlink PDU is the same as that of the first downlink PDU. The identification information of the quality of service flow included in the packet header information is the same, then the sequence number included in the packet header information of the second downlink PDU is equal to the sequence number included in the packet header information of the first downlink PDU and a preset value. and.

If the identification information of the quality of service flow contained in the packet header information of the second downlink PDU is different from the identification information of the quality of service flow contained in the packet header information of the first downlink PDU, the packet header information of the second downlink PDU contains the identification information of the quality of service flow. The sequence number has nothing to do with the sequence number included in the header information of the first downlink PDU; it will not be described in detail here.

Specifically, if the sequence numbers corresponding to the downlink PDUs carrying the identification information of the same quality of service flow may be increased in a sequential manner.

For example, if the preset value is equal to 1, the base station starts a timer when sending the first PDU carrying packet header information (ie, the first downlink PDU); wherein, the packet header information of the first PDU carrying packet header information includes: RQI , QoS flow 1, and sequence number 0. If the terminal fails to receive the RQI, the base station resends the second PDU (ie the second downlink PDU) carrying the header information after the timer expires or after determining that the terminal has not successfully received the RQI, wherein the second PDU carrying the header information The header information of the PDU includes: RQI, QoS flow 1 and sequence number 1.

It should be noted that, between the time when the base station sends the first downlink PDU and determines that the terminal fails to receive the RQI, the base station may also send a PDU carrying header information to the terminal. The serial number carried can be the same as the serial number carried in the header information of the first downlink PDU, or the serial number carried in the packet header information can be added with a preset value (which can be added each time a PDU carrying the packet header information is sent). 1). It should be further noted that, in this case, the base station determines that the sequence number carried in the header information of the PDU carrying the header information and sent to the terminal after the terminal fails to receive the RQI is a downlink PDU that is closest to the PDU in the time domain. The sum of the serial number carried in the packet header information and the preset value. For example, if the preset value is equal to 1, the base station starts the timer when sending the first PDU carrying packet header information; wherein, the packet header information of the first PDU carrying packet header information includes: RQI, QoS flow 1 and sequence number 0; Before the base station determines that the terminal has not successfully received the RQI, the base station also sends a second PDU carrying header information. At this time, the packet header information of the second PDU carrying the packet header information includes: RQI, QoS flow 1 and sequence number 1; the base station After sending the second PDU carrying header information, it is confirmed that the terminal has not successfully received the RQI. At this time, the base station needs to retransmit the PDU carrying the header information. At this time, the header information of the PDU includes: RQI, QoS flow 1 and sequence number 2. Not enumerated here.

It should be further noted that if the number of retransmissions of downlink PDUs carrying packet header information exceeds the maximum number of retransmissions, an error will be reported to the upper layer to avoid consistent repeated transmission and transmission failure, wasting resources; reporting errors in time can also improve maintenance efficiency.

Preferably, in the above-mentioned embodiment of the present invention, the step of sending the first feedback message to the base station within the first preset time length includes:

Send an uplink control PDU to the base station within a first preset time length; wherein, the uplink control PDU carries the first feedback message; or,

Send the uplink data PDU to the base station within a first preset time length; wherein, the packet header of the uplink data PDU carries the first feedback message.

The step of sending the second feedback message to the base station within the second preset time length includes:

Send an uplink control PDU to the base station within a second preset time length; wherein, the uplink control PDU carries the second feedback message; or,

If the uplink data PDU is sent to the base station within the second preset time length; wherein, the packet header of the uplink data PDU carries the second feedback message.

Preferably, there are two options for the design of the above-mentioned upstream PDU:

Option 1: when the uplink PDU is an uplink control PDU, the uplink control PDU carries the first feedback message or the second feedback message. The uplink control PDU is used to specifically indicate the sequence number carried in the downlink PDU received by the terminal. In this case, the uplink data PDU does not need to carry the serial number. In order to make a compromise between reliability and cost saving, one or more of the above-mentioned uplink control PDUs may be sent within a period of time, which is not specifically limited here.

Option 2: When the uplink PDU is an uplink data PDU, the data packet header of the uplink data PDU carries the first feedback message or the second feedback message. By carrying the sequence number in the uplink data PDU to implicitly indicate that the RQI carried in the downlink PDU has been successfully received, this option requires adding the SN field to the data packet header of the uplink data PDU, and the SN field is used to indicate the corresponding downlink PDU. carried serial number.

To sum up, in the above-mentioned embodiments of the present invention, by sending the identification information of the quality of service flow and the sequence number based on the granularity of the quality of service flow corresponding to the downlink PDU while sending the RQI, when the terminal successfully receives the downlink PUD carrying the packet header information It is necessary to send a feedback message to the base station to indicate whether the terminal has successfully received the RQI through the feedback message. If the base station determines that the terminal has successfully received the RQI, there is no need to send the RQI until the next reflection QoS transmission is required; if the base station determines that the terminal has not successfully received the RQI , the base station needs to retransmit the downlink PDU carrying the packet header information; the transmission method provided by the embodiment of the present invention can ensure that the terminal successfully receives the RQI, and can also save overhead.

As shown in FIG. 4 , an embodiment of the present invention further provides a base station, including a processor 400 and a transceiver 410, where the processor 400 is configured to perform the following processes:

Determine the first downlink protocol data unit PDU carrying packet header information; wherein, the packet header information includes: the reflected service quality indicator RQI, the identification information of the quality of service flow in the current downlink transmission, and the corresponding first downlink PDU. The sequence number of the quality of service flow granularity; the RQI is used to indicate that the mapping relationship between the quality of service flow and the data radio bearer in downlink transmission is suitable for uplink transmission;

The transceiver 410 is used to perform the following processes:

Send the first downlink PDU carrying packet header information to the terminal.

Preferably, the processor 400 in the above-mentioned embodiment of the present invention is configured to perform the following processes:

The first feedback message sent by the terminal is received within the first preset time length, and it is determined that the terminal successfully receives the RQI; wherein, the first feedback message carries the identification information of the quality of service flow and the information related to the the sequence number based on the QoS flow granularity corresponding to the first downlink PDU;

If the first feedback message sent by the terminal is not received within the first preset time length, it is determined that the terminal has not successfully received the RQI.

Preferably, the processor 400 in the above-mentioned embodiment of the present invention is configured to perform the following processes:

The second feedback message sent by the terminal is received within the second preset time length; if the second feedback message carries the identification information of the quality of service flow, and the quality of service-based service corresponding to the first downlink PDU is carried in the second feedback message The sequence number of the flow granularity and the confirmation ACK character determine that the terminal successfully receives the RQI; if the second feedback message carries the identification information of the quality of service flow, the service-based The sequence number of the mass flow granularity and the unacknowledged NACK character, to determine that the terminal has not successfully received the RQI;

If the second feedback message sent by the terminal is not received within the second preset time length, it is determined that the terminal fails to receive the RQI successfully.

Preferably, the transceiver 410 in the above-mentioned embodiment of the present invention is also used for:

sending the second downlink PDU carrying the packet header information to the terminal; or,

Send a third downlink PDU that does not carry the packet header information to the terminal.

Preferably, in the above-mentioned embodiment of the present invention, when the second downlink PDU carrying the packet header information is sent to the terminal, if the identification information of the quality of service flow contained in the packet header information of the second downlink PDU is the same as the The identification information of the quality of service flow contained in the packet header information of the first downlink PDU is the same, then the sequence number contained in the packet header information of the second downlink PDU is equal to the sequence number contained in the packet header information of the first downlink PDU. The sum of the number and a preset value.

Preferably, the transceiver 410 in the above-mentioned embodiment of the present invention is also used for:

The uplink control PDU sent by the terminal is received within a first preset time length; wherein, the uplink control PDU carries the first feedback message; or,

The uplink data PDU sent by the terminal is received within the first preset time length; wherein, the packet header of the uplink data PDU carries the first feedback message.

Preferably, the processor 400 in the above-mentioned embodiment of the present invention is further used for:

The uplink control PDU sent by the terminal is received within the second preset time length; wherein, the uplink control PDU carries the second feedback message; or,

The uplink data PDU sent by the terminal is received within the second preset time length, wherein the packet header of the uplink data PDU carries the second feedback message.

To sum up, in the above-mentioned embodiments of the present invention, by sending the identification information of the quality of service flow and the sequence number based on the granularity of the quality of service flow corresponding to the downlink PDU while sending the RQI, when the terminal successfully receives the downlink PUD carrying the packet header information It is necessary to send a feedback message to the base station to indicate whether the terminal has successfully received the RQI through the feedback message. If the base station determines that the terminal has successfully received the RQI, there is no need to send the RQI until the next reflection QoS transmission is required; if the base station determines that the terminal has not successfully received the RQI , the base station needs to retransmit the downlink PDU carrying the packet header information; the transmission method provided by the embodiment of the present invention can ensure that the terminal successfully receives the RQI, and can also save overhead.

It should be noted that, the base station provided by the above-mentioned embodiments of the present invention is a base station capable of executing the above-mentioned method for transmitting protocol data unit PDU, and all the above-mentioned embodiments of the above-mentioned method for transmitting protocol data unit PDU are applicable to the base station, and can achieve the same or similar beneficial effects.

As shown in FIG. 5 , an embodiment of the present invention further provides a terminal, including a processor 500 and a transceiver 510, the terminal further includes a user interface 520, and the transceiver 510 is configured to perform the following processes:

Receive the first downlink protocol data unit PDU that carries packet header information and is sent by the base station; wherein the packet header information includes: the reflected service quality indicator RQI, the identification information of the quality of service flow in the current downlink transmission, and the first downlink PDU. The corresponding sequence number based on the granularity of the quality of service flow; the RQI is used to indicate that the mapping relationship between the quality of service flow and the data radio bearer in the downlink transmission is applicable to the uplink transmission;

The processor 500 is configured to perform the following processes:

Parse the first downlink PDU to determine whether the RQI is successfully received.

Preferably, the transceiver 510 in the above-mentioned embodiment of the present invention is also used for:

If the terminal successfully receives the RQI, it sends a first feedback message to the base station within a first preset time length; wherein, the first feedback message carries the identification information of the quality of service flow and the first downlink PDU. Corresponding sequence number based on QoS flow granularity;

If the terminal fails to receive the RQI, the terminal does not send the first feedback message to the base station within the first preset time length.

Preferably, the transceiver 510 in the above-mentioned embodiment of the present invention is also used for:

Send a second feedback message to the base station within a second preset time length; wherein, the second feedback message carries the identification information of the quality of service flow, the quality of service flow granularity-based identification information corresponding to the first downlink PDU sequence number and confirmation ACK character; or, the second feedback message carries the identification information of the quality of service flow, the sequence number based on the granularity of the quality of service flow corresponding to the first downlink PDU, and the unacknowledged NACK character;

Alternatively, the second feedback message is not sent to the base station within the second preset time length.

Preferably, the transceiver 510 in the above-mentioned embodiment of the present invention is also used for:

receiving the second downlink PDU that is sent by the base station and that carries the packet header information; or,

A third downlink PDU that does not carry the packet header information and is sent by the base station is received.

Preferably, the transceiver 510 in the above-mentioned embodiment of the present invention is also used for:

Send an uplink control PDU to the base station within a first preset time length; wherein, the uplink control PDU carries the first feedback message; or,

Send an uplink data PDU to the base station within a first preset time length; wherein, the packet header of the uplink data PDU carries the first feedback message.

Preferably, the transceiver 510 in the above-mentioned embodiment of the present invention is also used for:

Send an uplink control PDU to the base station within a second preset time length; wherein, the uplink control PDU carries the second feedback message; or,

If the uplink data PDU is sent to the base station within the second preset time length; wherein, the packet header of the uplink data PDU carries the second feedback message.

To sum up, in the above-mentioned embodiments of the present invention, by sending the identification information of the quality of service flow and the sequence number based on the granularity of the quality of service flow corresponding to the downlink PDU while sending the RQI, when the terminal successfully receives the downlink PUD carrying the packet header information It is necessary to send a feedback message to the base station to indicate whether the terminal has successfully received the RQI through the feedback message. If the base station determines that the terminal has successfully received the RQI, there is no need to send the RQI until the next reflection QoS transmission is required; if the base station determines that the terminal has not successfully received the RQI , the base station needs to retransmit the downlink PDU carrying the packet header information; the transmission method provided by the embodiment of the present invention can ensure that the terminal successfully receives the RQI, and can also save overhead.

It should be noted that the terminal provided by the above-mentioned embodiments of the present invention is a terminal capable of executing the above-mentioned method for transmitting protocol data unit PDU, and all the above-mentioned embodiments of the above-mentioned method for transmitting protocol data unit PDU are applicable to the terminal, and all can achieve the same or similar beneficial effects.

In order to better achieve the above object, an embodiment of the present invention further provides a communication device, including a memory, a processor, and a computer program stored in the memory and running on the processor, the processor executing all When the procedure is described, each process in the above-mentioned embodiment of the method for transmitting the protocol data unit PDU on the base station side is realized, and the same technical effect can be achieved. In order to avoid repetition, it is not repeated here; When the procedure is described, each process in the above-mentioned embodiment of the terminal-side protocol data unit PDU transmission method is implemented, and the same technical effect can be achieved. In order to avoid repetition, details are not repeated here.

In order to better achieve the above purpose, an embodiment of the present invention further provides a computer-readable storage medium on which a computer program is stored, and when the program is executed by a processor, realizes the above-mentioned transmission of the protocol data unit PDU on the base station side Each process in the method embodiment can achieve the same technical effect, and in order to avoid repetition, it will not be repeated here. Wherein, the computer-readable storage medium, such as read-only memory (Read-Only Memory, referred to as ROM), random access memory (Random Access Memory, referred to as RAM), magnetic disk or optical disk, etc.; or, the program is processed Each process in the above-mentioned embodiment of the terminal-side protocol data unit PDU transmission method is implemented when the device is executed, and the same technical effect can be achieved. In order to avoid repetition, details are not repeated here. The computer-readable storage medium is, for example, a read-only memory (Read-Only Memory, ROM for short), a random access memory (Random Access Memory, RAM for short), a magnetic disk, or an optical disk.

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

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

These computer program instructions may also be stored in a computer-readable storage medium capable of directing a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce a paper product comprising the instruction means, The instruction means implements the functions specified in the flow or flows of the flowcharts and/or the block or blocks of the block diagrams.

These computer program instructions can also be loaded onto a computer or other programmable data processing device, causing the computer or other programmable device to perform a series of operational steps to produce a computer-implemented process, thereby causing the instructions to be executed on the computer or other programmable data processing device Steps are provided for implementing the functions specified in a flow or flows of the flowcharts and/or a block or blocks of the block diagrams.

The above are the preferred embodiments of the present invention. It should be pointed out that for those skilled in the art, without departing from the principles of the present invention, several improvements and modifications can be made. These improvements and modifications It should also be regarded as the protection scope of the present invention.

Claims (28)

1. A transmission method of a protocol data unit PDU, applied to a base station side, is characterized in that, comprising: Determine the first downlink protocol data unit PDU carrying packet header information; wherein, the packet header information includes: the reflected service quality indicator RQI, the identification information of the quality of service flow in the current downlink transmission, and the corresponding first downlink PDU. The sequence number of the quality of service flow granularity; the RQI is used to indicate that the mapping relationship between the quality of service flow and the data radio bearer in downlink transmission is suitable for uplink transmission; Send the first downlink PDU carrying packet header information to the terminal. 2. The transmission method according to claim 1, wherein after the step of sending the first downlink PDU carrying packet header information to the terminal, the transmission method further comprises: The first feedback message sent by the terminal is received within the first preset time length, and it is determined that the terminal successfully receives the RQI; wherein, the first feedback message carries the identification information of the quality of service flow and the information related to the the sequence number based on the QoS flow granularity corresponding to the first downlink PDU; If the first feedback message sent by the terminal is not received within the first preset time length, it is determined that the terminal has not successfully received the RQI. 3. The transmission method according to claim 1, wherein after the step of sending the first downlink PDU carrying packet header information to the terminal, the transmission method further comprises: The second feedback message sent by the terminal is received within the second preset time length; if the second feedback message carries the identification information of the quality of service flow, and the quality of service-based service corresponding to the first downlink PDU is carried in the second feedback message The sequence number of the flow granularity and the confirmation ACK character determine that the terminal successfully receives the RQI; if the second feedback message carries the identification information of the quality of service flow, the service-based The sequence number of the mass flow granularity and the unacknowledged NACK character, to determine that the terminal has not successfully received the RQI; If the second feedback message sent by the terminal is not received within the second preset time length, it is determined that the terminal fails to receive the RQI successfully. 4. The transmission method according to claim 2 or 3, wherein after the step of determining that the terminal fails to receive the RQI, the method further comprises: sending the second downlink PDU carrying the packet header information to the terminal; After the step of determining that the terminal successfully receives the RQI, the method further includes: Send a third downlink PDU that does not carry the packet header information to the terminal. 5. The transmission method according to claim 4, wherein when the second downlink PDU carrying the packet header information is sent to the terminal, if the quality of service flow included in the packet header information of the second downlink PDU is The identification information is the same as the identification information of the quality of service flow contained in the packet header information of the first downlink PDU, then the sequence number contained in the packet header information of the second downlink PDU is equal to the packet header information of the first downlink PDU The serial number contained in the sum of a preset value. 6. The transmission method according to claim 2, wherein the step of receiving the first feedback message sent by the terminal within the first preset time length comprises: The uplink control PDU sent by the terminal is received within a first preset time length; wherein, the uplink control PDU carries the first feedback message; or, The uplink data PDU sent by the terminal is received within the first preset time length; wherein, the packet header of the uplink data PDU carries the first feedback message. 7. The transmission method according to claim 3, wherein the step of receiving the second feedback message sent by the terminal within the second preset time length comprises: The uplink control PDU sent by the terminal is received within the second preset time length; wherein, the uplink control PDU carries the second feedback message; or, The uplink data PDU sent by the terminal is received within the second preset time length, wherein the packet header of the uplink data PDU carries the second feedback message. 8. A method for transmitting a protocol data unit PDU, applied to a terminal side, characterized in that it comprises: Receive the first downlink protocol data unit PDU that carries packet header information and is sent by the base station; wherein the packet header information includes: the reflected service quality indicator RQI, the identification information of the quality of service flow in the current downlink transmission, and the first downlink PDU. The corresponding sequence number based on the granularity of the quality of service flow; the RQI is used to indicate that the mapping relationship between the quality of service flow and the data radio bearer in the downlink transmission is applicable to the uplink transmission; Parse the first downlink PDU to determine whether the RQI is successfully received. 9. The transmission method according to claim 8, wherein after the step of parsing the first downlink PDU and determining whether the RQI is successfully received, the method further comprises: If the terminal successfully receives the RQI, it sends a first feedback message to the base station within a first preset time length; wherein, the first feedback message carries the identification information of the quality of service flow and the first downlink PDU. Corresponding sequence number based on QoS flow granularity; If the terminal fails to receive the RQI, the terminal does not send the first feedback message to the base station within the first preset time length. 10 . The transmission method according to claim 8 , wherein after the analysis of the first downlink PDU to determine whether the RQI is successfully received, the method further comprises: 10 . Send a second feedback message to the base station within a second preset time length; wherein, the second feedback message carries the identification information of the quality of service flow, the quality of service flow granularity-based identification information corresponding to the first downlink PDU sequence number and confirmation ACK character; or, the second feedback message carries the identification information of the quality of service flow, the sequence number based on the granularity of the quality of service flow corresponding to the first downlink PDU, and the unacknowledged NACK character; Alternatively, the second feedback message is not sent to the base station within the second preset time length. 11. The transmission method according to claim 9 or 10, wherein the transmission method further comprises: receiving the second downlink PDU that is sent by the base station and that carries the packet header information; or, A third downlink PDU that does not carry the packet header information and is sent by the base station is received. 12. The transmission method according to claim 9, wherein the step of sending the first feedback message to the base station within the first preset time length comprises: Send an uplink control PDU to the base station within a first preset time length; wherein, the uplink control PDU carries the first feedback message; or, Send the uplink data PDU to the base station within a first preset time length; wherein, the packet header of the uplink data PDU carries the first feedback message. 13. The transmission method according to claim 10, wherein the step of sending the second feedback message to the base station within the second preset time length comprises: Send an uplink control PDU to the base station within a second preset time length; wherein, the uplink control PDU carries the second feedback message; or, If the uplink data PDU is sent to the base station within the second preset time length; wherein, the packet header of the uplink data PDU carries the second feedback message. 14. A base station, comprising a processor and a transceiver, wherein the processor is configured to perform the following processes: Determine the first downlink protocol data unit PDU carrying packet header information; wherein, the packet header information includes: the reflected service quality indicator RQI, the identification information of the quality of service flow in the current downlink transmission, and the corresponding first downlink PDU. The sequence number of the quality of service flow granularity; the RQI is used to indicate that the mapping relationship between the quality of service flow and the data radio bearer in downlink transmission is suitable for uplink transmission The transceiver is used to perform the following processes: Send the first downlink PDU carrying packet header information to the terminal. 15. The base station according to claim 14, wherein the processor is configured to perform the following process: The first feedback message sent by the terminal is received within the first preset time length, and it is determined that the terminal successfully receives the RQI; wherein, the first feedback message carries the identification information of the quality of service flow and the information related to the the sequence number based on the QoS flow granularity corresponding to the first downlink PDU; If the first feedback message sent by the terminal is not received within the first preset time length, it is determined that the terminal has not successfully received the RQI. 16. The base station according to claim 14, wherein the processor is configured to perform the following process: The second feedback message sent by the terminal is received within the second preset time length; if the second feedback message carries the identification information of the quality of service flow, and the quality of service-based service corresponding to the first downlink PDU is carried in the second feedback message The sequence number of the flow granularity and the confirmation ACK character determine that the terminal successfully receives the RQI; if the second feedback message carries the identification information of the quality of service flow, the service-based The sequence number of the mass flow granularity and the unacknowledged NACK character, to determine that the terminal has not successfully received the RQI; If the second feedback message sent by the terminal is not received within the second preset time length, it is determined that the terminal fails to receive the RQI successfully. 17. The base station according to claim 15 or 16, wherein the transceiver is further configured to: sending the second downlink PDU carrying the packet header information to the terminal; or, Send a third downlink PDU that does not carry the packet header information to the terminal. 18. The base station according to claim 17, wherein when the second downlink PDU carrying the packet header information is sent to the terminal, if the identifier of the quality of service flow included in the packet header information of the second downlink PDU is The information is the same as the identification information of the quality of service flow included in the header information of the first downlink PDU, then the sequence number included in the header information of the second downlink PDU is equal to the header information of the first downlink PDU. Contains the serial number plus a default value. 19. The base station of claim 15, wherein the transceiver is further configured to: The uplink control PDU sent by the terminal is received within a first preset time length; wherein, the uplink control PDU carries the first feedback message; or, The uplink data PDU sent by the terminal is received within the first preset time length; wherein, the packet header of the uplink data PDU carries the first feedback message. 20. The base station according to claim 16, wherein the transceiver is further configured to: The uplink control PDU sent by the terminal is received within the second preset time length; wherein, the uplink control PDU carries the second feedback message; or, The uplink data PDU sent by the terminal is received within the second preset time length, wherein the packet header of the uplink data PDU carries the second feedback message. 21. A terminal comprising a processor and a transceiver, wherein the transceiver is used to perform the following process: Receive the first downlink protocol data unit PDU that carries packet header information and is sent by the base station; wherein the packet header information includes: the reflected service quality indicator RQI, the identification information of the quality of service flow in the current downlink transmission, and the first downlink PDU. The corresponding sequence number based on the granularity of the quality of service flow; the RQI is used to indicate that the mapping relationship between the quality of service flow and the data radio bearer in the downlink transmission is applicable to the uplink transmission; The processor is configured to perform the following processes: Parse the first downlink PDU to determine whether the RQI is successfully received. 22. The terminal according to claim 21, wherein the transceiver is further used for: If the terminal successfully receives the RQI, it sends a first feedback message to the base station within a first preset time length; wherein, the first feedback message carries the identification information of the quality of service flow and the first downlink PDU. Corresponding sequence number based on QoS flow granularity; If the terminal fails to receive the RQI, the terminal does not send the first feedback message to the base station within the first preset time length. 23. The terminal according to claim 21, wherein the transceiver is further used for: Send a second feedback message to the base station within a second preset time length; wherein, the second feedback message carries the identification information of the quality of service flow, the quality of service flow granularity-based identification information corresponding to the first downlink PDU sequence number and confirmation ACK character; or, the second feedback message carries the identification information of the quality of service flow, the sequence number based on the granularity of the quality of service flow corresponding to the first downlink PDU, and the unacknowledged NACK character; Alternatively, the second feedback message is not sent to the base station within the second preset time length. 24. The terminal according to claim 22 or 23, wherein the transceiver is further used for: receiving the second downlink PDU that is sent by the base station and that carries the packet header information; or, A third downlink PDU that does not carry the packet header information and is sent by the base station is received. 25. The terminal according to claim 22, wherein the transceiver is further used for: Send an uplink control PDU to the base station within a first preset time length; wherein, the uplink control PDU carries the first feedback message; or, Send the uplink data PDU to the base station within a first preset time length; wherein, the packet header of the uplink data PDU carries the first feedback message. 26. The terminal according to claim 23, wherein the transceiver is further used for: Send an uplink control PDU to the base station within a second preset time length; wherein, the uplink control PDU carries the second feedback message; or, If the uplink data PDU is sent to the base station within the second preset time length; wherein, the packet header of the uplink data PDU carries the second feedback message. 27. A communication device, comprising a memory, a processor, and a computer program stored on the memory and running on the processor; characterized in that, when the processor executes the program, the program as claimed in claim 1 is implemented The transmission method of the protocol data unit PDU of any one of -7; or, When the processor executes the program, the method for transmitting a protocol data unit (PDU) according to any one of claims 8-13 is implemented. 28. A computer-readable storage medium on which a computer program is stored, characterized in that, when the program is executed by a processor, a method for transmitting a protocol data unit (PDU) according to any one of claims 1-7 is realized when the program is executed. steps; or, When the program is executed by the processor, the steps in the method for transmitting a protocol data unit (PDU) according to any one of claims 8-13 are implemented.