CN108811094A - A kind of data transmission method - Google Patents

Abstract

The present application provides a data transmission method, which is applied to a system including a base station and a UE working on a single subband. The method includes: within a PDCCH cycle, the base station sends downlink authorization information on the PDCCH, and repeats the downlink transmission on the PDCCH for the last time. When the authorization information ends, transmit downlink data on the PDSCH according to the downlink authorization information; when the UE ends receiving the downlink data on the PDSCH, delay the first preset processing delay, and send feedback information for the downlink data on the PUCCH; The base station indicates in the downlink control information DCI sent on the PDCCH channel separated from the current PDCCH period by at least one PDCCH period that new data or retransmission data for the downlink data is sent. The method can enable a UE working on a single subband to complete service transmission.

Description

A method of data transmission

technical field

The invention relates to the field of communication technology, in particular to a data transmission method.

Background technique

In the broadband access system based on TD-LTE technology, the available bandwidth of the system is divided into multiple continuous or discontinuous sub-bands, and each sub-band is transmitted using Orthogonal Frequency Division Multiplexing (OFDM) technology. The subbands are divided into synchronous subbands, broadcast subbands and service subbands according to their functions. The synchronization subband is used for sending downlink synchronization signals, the broadcast subband is used for downlink broadcast and uplink random access, and the service subband is used for transmitting services.

In order to reduce the cost of the terminal, the system supports a single sub-band working mode, and each physical channel must be sent independently on each sub-band. The terminal chooses to work on all or part of the subbands according to different hardware capabilities, and the terminal with the weakest capability only works on a single subband.

A typical application scenario is the wireless broadband access network of the power system, referred to as TD-LTE230 network, its spectrum is discretely distributed in the 230M frequency band, and its bandwidth is 8.15MHz. is 223.525MHz, and the subband of the highest frequency point is 231.65MHz.

In the LTE system, the minimum TTI is a subframe, the Physical Downlink Control Channel (PDCCH) is scheduled in the same subframe (Physical Downlink Shared Channel, PDSCH), and the Physical Uplink Shared Channel (PUSCH) is scheduled across subframes . In the NB-IOT system, the minimum TTI is a subframe, PDCCH needs to schedule PDSCH and PUSCH across subframes, and supports transmission across multiple subframes, and PDCCH is sent periodically. In both the LTE system and the NB-IOT system, the control channel occupies the entire system bandwidth.

The minimum TTI of the TD-LTE 230 system is a radio frame, and PDCCH needs to schedule PDSCH and PUSCH across radio frames. At the same time, the system supports a single subband working mode, the PDCCH channel is sent independently in each subband, and the terminal only needs to monitor a single subband. Therefore, the TD-LTE 230 system needs to define a new transmission mechanism.

Contents of the invention

In view of this, the present application provides a data transmission method, which can enable a UE working on a single subband to complete service transmission.

In order to solve the problems of the technologies described above, the technical solution of the present application is achieved in the following way:

A data transmission method, applied to a system including a base station and a UE operating in a single subband, the method comprising:

In a PDCCH period, the base station sends downlink authorization information on the PDCCH, and when the last repeated transmission of the downlink authorization information on the PDCCH ends, transmits downlink data on the PDSCH according to the downlink authorization information;

When the UE finishes receiving downlink data on the PDSCH, delay the first preset processing delay, and send feedback information for the downlink data on the PUCCH;

The base station indicates in the downlink control information DCI sent on the PDCCH channel at least one PDCCH period apart from the current PDCCH period that new data or retransmission data for the downlink data is sent.

Wherein, the method further includes:

When the base station sends a filling message indicating that the downlink buffer is empty, no corresponding NDI indication is sent.

Wherein, the method further includes:

When the UE's first service arrives, it monitors the PDCCH of the resident subband. If the downlink service arrives, it monitors the downlink authorization information, and transmits the downlink service on the PDSCH channel of the subband assigned by the downlink authorization information, and transmits the downlink service on the PUCCH channel of the subband. transmitting the feedback information of the downlink service on the channel, wherein the resident subband is allocated for the UE during the random access process;

During service transmission, the UE monitors the PDCCH of the subband allocated by the grant information all the time.

Wherein, the method further includes:

In a PDCCH period, the base station sends uplink grant information on the PDCCH;

When the UE receives the uplink authorization information repeatedly sent by the base station on the PDCCH for the last time, it waits for a second preset processing delay, and transmits uplink data on the physical uplink shared channel PUSCH according to the uplink authorization information;

The base station indicates in the DCI sent on the PDCCH channel at least one PDCCH period apart from the current PDCCH period that what is sent uplink is new data, or retransmitted data for the uplink data.

Wherein, the method further includes:

The UE sends a buffer status report BSR indicating that the uplink buffer is empty;

When the base station receives the BSR, it does not send a corresponding NDI indication.

Wherein, the method further includes:

When the UE's first service arrives, it monitors the PDCCH of the resident subband. If the uplink service arrives, it monitors the uplink authorization information, and transmits the uplink service on the PUSCH channel of the subband allocated by the uplink authorization information. Among them, the resident subband is in the allocated for the UE during the random access process;

During service transmission, the UE monitors the PDCCH of the subband allocated by the grant information all the time.

Wherein, the method further includes:

Within a PDCCH period, the base station sends uplink and downlink simultaneous authorization information on the PDCCH, and when the last repeated transmission of the uplink and downlink simultaneous authorization information on the PDCCH ends, the base station sends the downlink authorization information based on the uplink and downlink simultaneous authorization information. Transmitting downlink data on the PDSCH, and waiting for a second preset processing delay, the UE transmits uplink data on the PUSCH according to the uplink grant in the uplink and downlink simultaneous grant information;

When the UE finishes receiving downlink data on the PDSCH, delay the first preset processing delay, and send feedback information for the downlink data on the PUCCH;

In the DCI sent by the base station on the PDCCH channel at least one PDCCH cycle apart from the current PDCCH cycle, respectively indicate that the uplink is sending new data, or for the retransmission data of the uplink data, and the downlink is sending new data, or for the Retransmission data of downlink data.

Wherein, the method further includes:

For the UE, if the uplink data is transmitted on the PUSCH and the acknowledgment ACK/non-acknowledgment NACK of the PDSCH needs to be transmitted on the PUCCH at the same time, the ACK/NACK of the PDSCH feedback is preferentially transmitted on the PUCCH.

Wherein, the method further includes:

When the UE's first service arrives, it monitors the PDCCH of the resident subband. If the uplink and downlink services arrive at the same time, it monitors the uplink and downlink simultaneous authorization information, and performs uplink service transmission on the PUSCH channel of the subband allocated by the uplink and downlink simultaneous authorization information. PDSCH The downlink service is transmitted on the channel, and the feedback information of the downlink service is transmitted on the PUCCH channel, wherein the resident subband is allocated for the UE during the random access process;

During service transmission, the UE monitors the PDCCH of the subband allocated by the grant information all the time.

Wherein, the method further includes:

During the service transmission process of the UE, if a PDCCH period arrives but the DCI is not for the UE, and there is a PDSCH hybrid automatic repeat request HARQ process or a PUSCH HARQ process waiting for the NDI indication, start the NDI waiting timer;

When the timer expires and no NDI indication of the PDSCH HARQ process or the PUSCH HARQ process is received, return to the resident subband and reset all HARQ processes.

It can be seen from the above technical solution that the data transmission mechanism is defined in this application. When the UE ends receiving downlink data on the PDSCH, it delays the first preset processing delay, and sends feedback information for the downlink data on the PUCCH; The downlink control information (Downlink Control Information, DCI) sent on the PDCCH channel at least one PDCCH period apart from the current PDCCH period indicates whether to retransmit data, so that the UE working on a single subband can complete service transmission.

Description of drawings

FIG. 1 is a schematic diagram of a downlink data transmission process in an embodiment of the present application;

FIG. 2 is a schematic diagram of downlink data transmission timing in an embodiment of the present application;

FIG. 3 is a schematic diagram of an uplink data transmission process in an embodiment of the present application;

FIG. 4 is a schematic diagram of uplink data transmission timing in an embodiment of the present application;

FIG. 5 is a schematic flowchart of simultaneous transmission of uplink and downlink data in an embodiment of the present application.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described in detail below with reference to the accompanying drawings and examples.

In the embodiment of the present application, a data transmission method is provided, which is applied to a system including a base station and a UE working on a single subband. The scheme defines a data transmission mechanism. When the UE ends receiving downlink data on the PDSCH, the first preset processing is delayed. Delay, sending feedback information for the downlink data on the PUCCH; the base station indicates whether to retransmit the data in the downlink control information (Downlink Control Information, DCI) sent on the PDCCH channel at least one PDCCH period apart from the current PDCCH period, A UE capable of working on a single subband completes service transmission.

The data transmission process in the embodiment of the present application will be described in detail below with reference to the accompanying drawings. The UE in this embodiment of the present application is a UE working on a single subband.

Embodiment one

Referring to FIG. 1 , FIG. 1 is a schematic diagram of a downlink data transmission process in an embodiment of the present application. The specific steps are:

Step 101 , within a PDCCH cycle, the base station sends downlink authorization information on the PDCCH, and transmits downlink data on the PDSCH according to the downlink authorization information when the last repeated transmission of the downlink authorization information on the PDCCH ends.

Step 102, when the UE finishes receiving downlink data on the PDSCH, delay the first preset processing delay, and send feedback information for the downlink data on a physical uplink control channel (Physical Uplink Control CHannel, PUCCH).

Step 103 , the base station indicates in the DCI sent on the PDCCH channel at least one PDCCH period apart from the current PDCCH period that new data is sent, or retransmitted data for the downlink data.

In this step, the New Date Indication (NDI) in DCI is used to indicate:

When the content of NDI is 0, it means that the authorization to send on the corresponding PDSCH is retransmission data;

When the content of the NDI is 1, it means that new data is authorized to be sent on the corresponding PDSCH.

When the base station has no downlink data that needs to be sent to the corresponding UE, the base station sends a filling message indicating that the downlink buffer is empty, and does not send a corresponding NDI indication, that is, it does not retransmit by default.

The corresponding NDI indication is not sent here. Compared with when the UE sends downlink data, the NDI in the DCI sent by the base station on the PDCCH channel at least one PDCCH period apart from the current PDCCH period indicates that new data is sent, or for the downlink data. The base station sends a filling message indicating that the downlink buffer is empty, and does not send the corresponding NDI indication. As for whether to send DCI indication or other information, there is no limitation in this embodiment of the application.

Among them, the longest PDCCH transmission time is not greater than the maximum number of PDCCH repetitions configured in the Radio Resource Control (RRC) message, and the actual transmission time is related to the number of DCI repetitions in the DCI configuration; the longest PDSCH transmission time may last until the current PDCCH cycle In the end, the actual transfer time depends on the DCI configuration.

Referring to FIG. 2 , FIG. 2 is a schematic diagram of downlink data transmission timing in an embodiment of the present application.

In FIG. 2, the UE receives the downlink data from the PDSCH at the end time, and then delays the first preset processing delay, and sends the feedback information for the downlink data on the PUCCH.

The base station indicates in the DCI sent on the PDCCH channel separated by one PDCCH period from the current PDCCH period that new data is sent, or retransmitted data for the downlink data.

The above description is for the data transmission in the downlink time domain, and the related process for the service data transmission in the downlink frequency domain is given below:

When the UE's first service arrives, it monitors the PDCCH of the resident subband. If the downlink service arrives, it monitors the downlink authorization information, and transmits the downlink service on the PDSCH channel of the subband assigned by the downlink authorization information, and transmits the downlink service on the PUCCH channel of the subband. transmitting the feedback information of the downlink service on the channel, wherein the resident subband is allocated for the UE during the random access process;

During service transmission, the UE monitors the PDCCH of the subband allocated by the grant information all the time.

Embodiment two

Referring to FIG. 3 , FIG. 3 is a schematic diagram of an uplink data transmission process in an embodiment of the present application. The specific steps are:

In step 301, the base station sends uplink grant information on the PDCCH within one PDCCH period.

Step 302: After receiving the uplink authorization information repeatedly sent by the base station on the PDCCH for the last time, the UE waits for a second preset processing time delay, and transmits uplink data on the PUSCH according to the uplink authorization information.

Step 303 , the base station indicates in the DCI sent on the PDCCH channel at least one PDCCH period apart from the current PDCCH period that the uplink transmission is new data, or retransmission data for the uplink data.

In this step, the NDI in the DCI is used to indicate that the uplink is sending new data, or retransmission data for the uplink data:

When the content of NDI is 0, it means NACK and the authorization to send on the corresponding PUSCH is retransmission data;

When the content of NDI is 1, it means ACK and what is authorized to be sent on the corresponding PUSCH is new data.

The UE sends a buffer status report (BSR) indicating that the uplink buffer is empty;

When the base station receives the BSR, it does not send a corresponding NDI indication.

The corresponding NDI indication is sent here. Compared with when the UE is sending uplink data, the NDI in the DCI sent by the base station on the PDCCH channel at least one PDCCH period apart from the current PDCCH period indicates that new data is sent uplink, or for the uplink Data retransmission data; when the UE sends a BSR indicating that the uplink buffer is empty, and the base station receives the BSR, the base station does not need to send the corresponding NDI indication. As for whether to send DCI indication other information, there is no limitation in this embodiment of the application.

Among them, the longest PDCCH transmission time is not greater than the maximum number of repetitions of the PDCCH configured in the RRC message, and the actual transmission time is related to the number of DCI repetitions in the DCI configuration; the longest transmission time of the PUSCH can last until the PDCCH transmission time of the next PDCCH period plus the second preset The processing delay is assumed, and the actual transmission time depends on the DCI configuration.

The first preset processing delay and the second preset processing delay may be the same or different, and are configured according to actual applications, but both the first preset processing delay and the second preset processing time take wireless frames as a unit.

Referring to FIG. 4 , FIG. 4 is a schematic diagram of uplink data transmission timing in an embodiment of the present application. In FIG. 4, when the sending of the uplink authorization information on the PDCCH ends, the second preset processing time is delayed, and the uplink data is transmitted on the PUSCH.

And the feedback information for the uplink data is indicated in the DCI sent on the PDCCH channel with an interval of one PDCCH period.

The above description is for the data transmission in the uplink time domain, and the related process for the service data transmission in the uplink frequency domain is given below:

When the UE's first service arrives, it monitors the PDCCH of the resident subband. If the uplink service arrives, it monitors the uplink authorization information and performs uplink service transmission on the PUSCH channel of the subband assigned by the uplink authorization information; where the resident subband is allocated for the UE during the random access process;

During service transmission, the UE monitors the PDCCH of the subband allocated by the grant information all the time.

Embodiment three

Referring to FIG. 5 , FIG. 5 is a schematic flowchart of simultaneous transmission of uplink and downlink data in an embodiment of the present application. The specific steps are:

Step 501 , within one PDCCH period, the base station sends uplink and downlink simultaneous grant information including uplink grant and downlink grant on the PDCCH.

Step 502, when the base station finishes repeatedly transmitting the uplink and downlink simultaneous authorization information on the PDCCH for the last time, transmit the downlink data on the PDSCH according to the downlink authorization in the uplink and downlink simultaneous authorization information, and wait for the second preset processing delay, and the UE according to the uplink and downlink simultaneous authorization information. In the above simultaneous uplink and downlink grant information, the uplink grant is to transmit uplink data on the PUSCH.

Step 503, when the UE finishes receiving downlink data on the PDSCH, delay the first preset processing time delay, and send feedback information for the downlink data on the PUCCH.

Step 504, the base station respectively indicates in the DCI sent on the PDCCH channel at least one PDCCH period apart from the current PDCCH period that new data is sent uplink, or new data is sent downlink for the retransmitted data of the uplink data, or Retransmit data for the downlink data.

In this step, two NDIs in DCI are used for instructions:

An NDI is used to indicate downlink related information, specifically: when the content of the NDI is 0, it means that the authorization to send on the corresponding PDSCH is retransmission data;

When the content of the NDI is 1, it means that new data is authorized to be sent on the corresponding PDSCH.

Use another NDI to indicate uplink related information, specifically: when the content of NDI is 0, it means NACK and the authorization to send on the corresponding PUSCH is retransmission data;

When the content of NDI is 1, it means ACK and what is authorized to be sent on the corresponding PUSCH is new data.

In the specific embodiment of the present application, no matter in the related NDI of uplink or downlink, the content represented by 0 or 1 can also be exchanged, as long as the base station and the UE both agree that the content represented is consistent.

When the base station sends a filling message indicating that the downlink buffer is empty, no corresponding NDI indication is sent.

The UE sends a BSR indicating that the uplink buffer is empty;

When the base station receives the BSR, it does not send a corresponding NDI indication.

The above description is for data transmission in the uplink and downlink time domains, and the related process of service data transmission in the uplink and downlink frequency domains is given below:

When the UE's first service arrives, it monitors the PDCCH of the resident subband. If the uplink and downlink services arrive at the same time, it monitors the uplink and downlink simultaneous authorization information, and performs uplink service transmission on the PUSCH channel of the subband allocated by the uplink and downlink simultaneous authorization information. PDSCH The downlink service is transmitted on the channel, and the feedback information of the downlink service is transmitted on the PUCCH channel, wherein the resident subband is allocated for the UE during the random access process;

During service transmission, the UE monitors the PDCCH of the subband allocated by the grant information all the time.

For the UE, if the uplink data is transmitted on the PUSCH and the acknowledgment (ACK)/(non-acknowledgement) NACK of the PDSCH needs to be transmitted on the PUCCH at the same time, the ACK/NACK of the PDSCH is preferentially transmitted on the PUCCH.

The dedicated PDCCH search spaces of different user terminals may overlap, and service transmission does not preempt within the PDCCH period, but when a new PDCCH period arrives, high-priority services can be allocated first.

The common PDCCH search space is used for paging and random access response, and may also overlap with the user's dedicated PDCCH search space.

The same user performs paging, random access, or service transmission according to the status. The three will not happen at the same time, but resource conflicts may occur between different users. The order of priority from high to low is paging>random Access response > service, paging can preempt random access response and service transmission, and random access response can preempt service transmission.

During the service transmission process of the UE, if a PDCCH cycle arrives but the DCI is not targeted at the UE, and there is a PDSCH Hybrid Automatic Repeat reQuest (HARQ) process or a PUSCH HARQ process waiting for the NDI indication, start the NDI waiting timing device;

When the timer expires and no NDI indication of the PDSCH HARQ process or the PUSCH HARQ process is received, return to the resident subband and reset all HARQ processes.

To sum up, the present application defines a data transmission mechanism, enabling UEs working on a single subband to complete service transmission.

The embodiment of the present application also provides a processing mechanism when multi-user resource conflicts occur. In the normal transmission process and the transmission interruption process, ensure that the terminal monitors the single subband to effectively identify the transmission status and complete the service transmission.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the present invention. within the scope of protection.

Claims (10)

1. a kind of data transmission method, be applied to include base station and the system of user terminal UE that list band works in, feature It is, this method includes：

In one physical downlink control channel PDCCH period, base station sends downstream grants information on PDCCH, on PDCCH most Afterwards when the primary repetition transmission downstream grants end of message, according to the downstream grants information in Physical Downlink Shared Channel PDSCH Upper transmission downlink data；

UE postpones the first default processing delay, physically row control channel at the end of receiving downlink data on PDSCH The feedback information for the downlink data is sent on PUCCH；

Base station is at least being spaced the Downlink Control Information sent on the PDCCH channels in a PDCCH period with the current PDCCH periods What instruction was sent in DCI is new data, or for the re-transmission data of the downlink data.

2. according to the method described in claim 1, it is characterized in that, the method further includes：

When base station sends the filling message for indicating down buffer storage as sky, corresponding new data instruction NDI instructions are not sent.

3. according to the method described in claim 1, it is characterized in that, the method further includes：

When the first business of UE reaches, the PDCCH of residence sub-band is monitored, if downlink business reaches, then monitors downstream grants information, And downlink traffic transmission is carried out on the PDSCH channels of the subband in the distribution of downstream grants information, and in the PUCCH channels of the subband The feedback information of the upper transmission downlink business wherein, residence sub-band be in the random access procedure what the UE was distributed；

In business transmission process, UE monitors always the PDCCH of the subband of authorization message distribution.

4. according to the method described in claim 1, it is characterized in that, the method further includes：

In one PDCCH period, base station sends uplink authorization information on PDCCH；

UE waits for the second default processing at the end of receiving the uplink authorization information that base station repetition is sent on PDCCH for the last time Time delay transmits upstream data according in the uplink authorization information physically shared channel PUSCH of row；

Base station is at least spaced in the DCI sent on the PDCCH channels in a PDCCH period with the current PDCCH periods in instruction What row was sent is new data, or for the re-transmission data of the upstream data.

5. according to the method described in claim 4, it is characterized in that, the method further includes：

The UE, which is sent, indicates uplink caching for empty buffer status report BSR；

When the base station receives the BSR, corresponding NDI instructions are not sent.

6. according to the method described in claim 4, it is characterized in that, the method further includes：

When the first business of UE reaches, the PDCCH of residence sub-band is monitored, if uplink service reaches, then monitors uplink authorization information, And carrying out uplink traffic transmission wherein on the PUSCH channels of the subband in uplink authorization information distribution, residence sub-band is random It is UE distribution in access procedure；

In business transmission process, UE monitors always the PDCCH of the subband of authorization message distribution.

7. according to the method described in claim 1, it is characterized in that, the method further includes：

In one PDCCH period, base station sends the uplink and downlink comprising uplink authorization and downstream grants on PDCCH while authorizing letter Breath, at the end of repeating transmission uplink and downlink authorization message simultaneously on PDCCH for the last time, base station is awarded simultaneously according to the uplink and downlink Downstream grants transmit downlink data on PDSCH in power information, and wait for the second default processing delay, and UE is according to described upper and lower Uplink authorization transmits upstream data on PUSCH in row while authorization message；

UE postpones the first default processing delay at the end of receiving downlink data on PDSCH, is sent for described on PUCCH The feedback information of downlink data；

Base station is respectively referred to being at least spaced in the DCI sent on the PDCCH channels in a PDCCH period with the current PDCCH periods Show uplink transmission is new data, or for the re-transmission data of the upstream data, what downlink was sent is new data, or is directed to institute State the re-transmission data of downlink data.

8. the method according to the description of claim 7 is characterized in that the method further includes：

For the UE, if in PUSCH transmission upstream data, while needing the confirmation ACK/ of the transmission feedback PDSCH on PUCCH non- When confirming NACK, then the ACK/NACK of feedback PDSCH is preferentially transmitted on PUCCH.

9. the method according to the description of claim 7 is characterized in that the method further includes：

When the first business of UE reaches, the PDCCH of residence sub-band is monitored, if uplink and downlink business reaches simultaneously, then monitors uplink and downlink Authorization message simultaneously, and uplink traffic transmission is carried out on the PUSCH channels of the subband in uplink and downlink authorization message distribution simultaneously, Carry out downlink traffic transmission on PDSCH channels, the feedback information of downlink business described in PUCCH channels, wherein resident son It is in the random access procedure what the UE was distributed with being；

In business transmission process, UE monitors always the PDCCH of the subband of authorization message distribution.

10. according to claim 1-9 any one of them methods, which is characterized in that the method further includes：

UE is in business transmission process, if a PDCCH period reaches, DCI is not to be directed to this UE, and have PDSCH mixing certainly Dynamic retransmission request HARQ processes or PUSCH HARQ processes wait for NDI instructions, then start NDI waiting timers；

When timer expires, and the NDI instructions of PDSCH HARQ processes or PUSCH HARQ processes are not received, then return to resident son Band and reset all HARQ processes.