CN107809800B

CN107809800B - Method and equipment for sending data

Info

Publication number: CN107809800B
Application number: CN201610814710.7A
Authority: CN
Inventors: 汪勇刚; 晁华
Original assignee: Nokia Shanghai Bell Co Ltd
Current assignee: Nokia Shanghai Bell Co Ltd
Priority date: 2016-09-09
Filing date: 2016-09-09
Publication date: 2021-08-10
Anticipated expiration: 2036-09-09
Also published as: CN107809800A

Abstract

A method and apparatus for transmitting data to a second apparatus in a first apparatus of a wireless communication system, comprising: the first device sends a first number of transport blocks to the second device in each transmission time interval, wherein the first number is greater than 1.

Description

Method and equipment for sending data

Technical Field

The present invention relates to the field of wireless communication technologies, and in particular, to a data transmission method.

Background

In the current LTE-a evolution and the research of the future 5G communication system, low transmission delay (low transmission latency) is becoming an increasingly important issue. Given the increasing number of applications that require lower transmission delays to be achieved to ensure performance, the 3GPP standardization bodies have typically started to conduct research on low transmission delays, for example in view of the wide prospects of autopilot, remote control and certain TCP protocol-based applications.

Currently, in order to effectively reduce the transmission delay, one of the issues that is of great interest is to shorten the Transmission Time Interval (TTI), which is 14 OFDM symbols in length, i.e., 1ms, in the current LTE system. It is clear that if the TTI is shorter, the transmission delay will be significantly reduced. Thus, designs using shorter TTIs have become an obvious direction, e.g., using a TTI of 0.5 milliseconds (i.e., 7 OFDM symbols), and even shorter TTI designs (3/4 OFDM symbols or 2 or even 1 OFDM symbol) have become the direction of research.

However, new problems arise when using shorter TTIs, such as how efficiently to perform transmission scheduling. In some existing schemes, because a short TTI is introduced, more User Equipments (UEs) need to be scheduled in a unit time, and in order to schedule more UEs, new control signaling needs to be introduced, and these additional signaling reduce spectrum efficiency, and at the same time, cause incompatibility with an existing system, and the cost of improvement is too large.

On the other hand, considering that the reference signal and one layer of signaling always exist in the data transmission process, the simple method of improving the system performance by reducing the TTI is not applicable to all scenarios. For example, in an application scenario with low throughput, a short TTI may result in more signaling overhead for one layer, and may even result in degradation of system performance. This means that the overhead of one-layer signaling and two-layer signaling must be considered together to determine whether it is worth introducing a shorter TTI.

Therefore, a new data transmission method is needed, which can achieve the balance between throughput and transmission delay, is also suitable for the short TTI scenario, and is compatible with the existing system with low complexity.

Disclosure of Invention

In order to solve the above problems in the prior art, the present invention provides a new data transmission method, which enables multiple Transport Blocks (TBs) to be transmitted within one TTI by shortening the length of the Transport Blocks (TBs), thereby reducing signaling overhead for scheduling, and therefore, is more suitable for an application scenario with a short TTI. In contrast, the conventional approach is that one scheduling signaling schedules data transmission for one TTI, and one TTI contains only one TB. The new data transmission method is to keep one scheduling signaling scheduling one TTI (TTI length can be reduced from 1ms to 0.5 ms) to reduce signaling overhead, but one TTI may contain multiple short TBs.

Specifically, according to a first aspect of the present invention, a method for transmitting data to a second device in a first device in a wireless communication system is provided, including: the first device sends a first number of transport blocks to the second device in each transmission time interval, wherein the first number is greater than 1.

Preferably, the first number of transport blocks transmitted by the first device to the second device in each transmission time interval is the same.

Preferably, the first number of transport blocks sent by the first device to the second device in each transmission time interval is different.

More preferably, further comprising: the first device receives a second message sent from the second device, wherein when the second device successfully receives any one of the first number of transport blocks or combines and successfully receives any first number of the first number of transport blocks, the second device immediately sends the second message to the first device indicating that the reception is successful; when the second device fails to receive all the transport blocks in the first number of transport blocks, the second device sends the second message to the first device to indicate that the reception fails.

More preferably, further comprising: and after the first equipment receives the second message which is sent from the second equipment and indicates that the receiving is successful, the first equipment immediately sends a new transmission block.

More preferably, further comprising: the first device receives a second message sent from the second device, wherein when the second device successfully receives all the transport blocks in the first number of transport blocks, the second device sends the second message to the first device to indicate that the reception is successful; when the second device fails to receive any one of the first number of transport blocks, the second device sends the second message to the first device indicating a reception failure.

More preferably, further comprising: and when the first equipment receives the second message which is sent from the second equipment and indicates that the receiving fails, the first equipment retransmits the first quantity of transmission blocks.

More preferably, wherein the transmission time interval is 1 millisecond or 0.5 millisecond.

More preferably, further comprising: a first message sent by the first device to the second device, wherein the first message is used to indicate whether the first number of transport blocks is the same or different, and the first number.

More preferably, the first message is radio resource control signaling.

More preferably, the first device is a base station, the second device is a user equipment, and the first message is downlink control information.

More preferably, the first device is a user equipment, the second device is a base station, and the first message is an uplink scheduling request.

According to a second aspect of the present invention, a transceiver for transmitting data to a second device in a first device of a wireless communication system is proposed, the transceiver being configured to transmit a first number of transport blocks to the second device per transmission time interval by the first device, wherein the first number is larger than 1.

According to a third aspect of the present invention, a base station in a wireless communication system is proposed, wherein the base station comprises the above-mentioned transceiver.

According to a fourth aspect of the present invention, a user equipment in a wireless communication system is proposed, wherein the user equipment comprises the transceiver described above.

In the invention, a system can meet different application scenes by a mode of transmitting a plurality of TBs in one TTI: the same TB is sent in one TTI, so that the high-reliability and low-delay scene can be met; different TBs are sent in one TTI, so that the large data and high throughput scene can be met; the method can be applied to both standard TTI and short TTI, and the length of the TB can be flexibly configured; meanwhile, the method is basically compatible with the existing LTE system, the change of the existing control signaling is very small, the realization is very simple, and the aim of the invention is achieved.

Drawings

Other features, objects and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments thereof, which proceeds with reference to the accompanying drawings.

Fig. 1(a) shows a schematic diagram of downlink data transmission according to the present invention;

fig. 1(b) shows a schematic diagram of downlink data transmission according to the present invention;

fig. 2(a) shows a schematic diagram of uplink data transmission according to the present invention;

fig. 2(b) shows a schematic diagram of uplink data transmission according to the present invention;

fig. 3(a) shows a schematic diagram of downlink data transmission according to the present invention;

fig. 3(b) shows a schematic diagram of downlink data transmission according to the present invention;

fig. 4(a) shows a schematic diagram of uplink data transmission according to the present invention;

fig. 4(b) shows a schematic diagram of uplink data transmission according to the present invention.

Wherein the same or similar reference numerals indicate the same or similar step features or means/modules.

Detailed Description

In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings which form a part hereof. The accompanying drawings illustrate, by way of example, specific embodiments in which the invention may be practiced. The illustrated embodiments are not intended to be exhaustive of all embodiments according to the invention. It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present invention. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims.

First, for low transmission delay applications, there are two typical scenarios. The first type is applications represented by remote control and automatic driving, and the applications are characterized by discontinuous transmission, small data volume and high reliability and quick response; the second type is an application represented by TCP application, online game, and video conference, and is characterized by continuous transmission, large data volume, higher resource utilization rate requirement, and reduced overhead of control signaling. These requirements are in conflict with each other, which means that all requirements must not be met by using only short TTIs and new solutions must be found.

The present invention therefore proposes a new short TB-based data transmission method, i.e. more than one TB is transmitted in one TTI, thereby obtaining a reasonable balance between overhead and delay. And thus can be applied to various scenes. It is noted that this method, although invented primarily due to the introduction of short TTIs, is equally applicable to existing TTIs of standard length. That is, the TTI length to which the method of the present invention is applied may be a 1ms, i.e., 1ms TTI, or a 0.5ms, i.e., 0.5ms TTI.

On the other hand, the data transmission method of the invention is simultaneously suitable for uplink and downlink, namely, the mode of short TB can be used whether the base station sends data to the UE or the UE sends data to the base station.

On the basis, the invention further meets different requirements of the two types of applications by two modes of repetition and non-repetition.

Specifically, as shown in fig. 1(a), the length of each TTI is 1ms, the PDCCH occupies 3 OFDM symbols, the Reference Signal (RS) occupies 1 OFDM symbol, and the length of each short TB is 3 OFDM symbols, so that 3 short TBs can be transmitted in each TTI. It should be noted that the short TB length may be varied, as long as it is satisfied that more than one short TB may be transmitted in each TTI, for example, each short TB has a length of 5 OFDM symbols, and then 2 short TBs may be transmitted in each TTI. While figure 1(a) shows a repetition mode, i.e. all short TBs transmitted in each TTI are identical, all TB 1. This approach is mainly used for the first type of applications, ensuring a higher signal-to-noise ratio by repeatedly transmitting the same TB; the middle RS is inserted for higher channel estimation gain at the receiving end. Thereby ensuring high reliability requirements for the first type of application.

Further, in order to meet the requirement of the first type of application fast response, the UE at the receiving end may immediately send a second message indicating successful reception after successfully receiving any one short TB (or successfully receiving any previous several TBs of combined transmission in the presence of combined transmission), and may immediately send a new TB after receiving the second message indicating successful reception, thereby reducing round-trip time (RTT), and ensuring fast response. Correspondingly, the UE at the receiving end only sends the second message indicating the reception failure to request the base station to perform retransmission when all the short TBs are received and all the short TBs are found to be failed to be received.

Fig. 1(b) shows another downlink data transmission scheme according to the present invention, which is different from fig. 1(a) in that fig. 1(b) shows a non-repeating manner, that is, all short TBs transmitted in each TTI are different, namely TB1, TB2 and TB 3. This approach is mainly used for the second type of applications, and by sending multiple different TBs within one TTI, it is ensured that more data can be transmitted, providing higher resource utilization.

Further, in order to meet the requirement of the second type of application to reduce signaling overhead, a short TB bundling method may be used, that is, the UE sends the second message to indicate successful reception only after all short TBs in a TTI are successfully received, and if any short TB fails to be successfully received, the UE sends the second message to indicate reception failure, and requires the base station to retransmit all short TBs (TB1, TB2, TB3) in the TTI, and specifically, the second message may be an HARQ response.

Similarly, for the upstream, both repetition and non-repetition modes can be used as well. Fig. 2(a) shows an uplink data transmission scheme according to the present invention, as shown in the figure, each TTI is 1ms in length, a demodulation reference signal (DMRS) occupies 1 OFDM symbol, and each short TB is 3 OFDM symbols in length, so that 4 short TBs can be transmitted in each TTI. Fig. 2(a) shows a repetition mode, i.e. all short TBs transmitted in each TTI are identical, all TB 1.

Similarly, fig. 2(b) shows another uplink data transmission scheme according to the present invention, which is different from fig. 2(a) in that fig. 2(b) shows a non-repetitive manner, that is, all short TBs transmitted in each TTI are different from one another, namely TB1, TB2, TB3 and TB4, and TB1, TB2, TB3 and TB4 are bundled.

The above discussion is of the data transmission method at normal TTI length, and as mentioned before, the present invention is equally applicable to 0.5ms short TTI scenarios.

Specifically, as shown in fig. 3(a), the length of each TTI is 0.5ms, the PDCCH occupies 2 and 1 OFDM symbols in two TTIs, respectively, the Reference Signal (RS) occupies 1 OFDM symbol, and the length of each short TB is 2 OFDM symbols, so that 2 short TBs can be transmitted in each TTI. While figure 3(a) shows a repeating pattern, i.e. all short TBs transmitted within each TTI are identical, TB1 and TB2 respectively.

Fig. 3(b) shows another downlink data transmission scheme according to the present invention, which is different from fig. 3(a) in that fig. 3(b) shows a non-repeating manner, i.e., all short TBs transmitted in each TTI are different, respectively TB1, TB2, TB3, and TB 4. And TB1 and TB2, TB3 and TB 4.

Similarly, fig. 4(a) shows an uplink data transmission scheme according to the present invention, as shown in the figure, each TTI is 0.5ms in length, a demodulation reference signal (DMRS) occupies 1 OFDM symbol, and each short TB is 2 OFDM symbols in length, so that 2 short TBs can be transmitted in each TTI. While figure 4(a) shows a repeating pattern, i.e. all short TBs transmitted within each TTI are identical, TB1 and TB2 respectively.

Fig. 4(b) shows another uplink data transmission scheme according to the present invention, also according to another embodiment of the present invention, which is different from fig. 4(a) in that fig. 4(b) shows a non-repeating manner, i.e. all short TBs transmitted in each TTI are different from one another, namely TB1, TB2, TB3 and TB 4. And TB1 and TB2, TB3 and TB 4.

In addition, the transmitting end may also notify the receiving end of the configuration of the TBs through the first message, for example, indicating whether a repetition mode or a non-repetition mode is adopted, and the length of the short TB or the number of TBs transmitted in each TTI.

Specifically, the first message may be Radio Resource Control (RRC) signaling; or Downlink Control Information (DCI) when the transmitting end is a base station and the receiving end is a UE; or when the transmitting end is the UE and the receiving end is the base station, the UE is an uplink scheduling request (scheduling request, SR).

The following describes the apparatus corresponding to the above method, and the features of the units/devices are related to the features of the steps in the above method.

The present invention first proposes a transceiver for transmitting data to a second device in a first device of a wireless communication system, the transceiver being configured to transmit a first number of transport blocks to the second device in each transmission time interval, wherein the first number is greater than 1.

Further, the invention proposes a base station comprising the transceiver and a UE comprising the transceiver.

While embodiments of the present invention have been described above, the present invention is not limited to a particular system, device, and protocol, and various modifications and changes may be made by those skilled in the art within the scope of the appended claims.

Other variations to the disclosed embodiments can be understood and effected by those skilled in the art from a study of the specification, the disclosure, the drawings, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the word "a" or "an" does not exclude a plurality. In the present invention, "first" and "second" merely indicate names and do not represent order relationships. In practical applications of the invention, one element may perform the functions of several technical features recited in the claims. Any reference signs in the claims shall not be construed as limiting the scope.

Claims

1. A method of transmitting data to a second device in a first device of a wireless communication system, comprising:

the first device sends a first number of transport blocks to the second device in each transmission time interval, wherein the first number is greater than 1;

the first device sends a first message to the second device, wherein the first message is used for indicating whether the first number of transmission blocks are the same or different and the first number.

2. The method of claim 1, wherein the first number of transport blocks transmitted by the first device to the second device in each transmission time interval is the same.

3. The method of claim 1, wherein the first number of transport blocks transmitted by the first device to the second device in each transmission time interval is different.

4. The method of claim 2, further comprising:

the first device receives a second message sent from the second device, wherein,

when the second device successfully receives any one of the first number of transmission blocks, or combines and successfully receives any first number of transmission blocks of the first number of transmission blocks, the second device immediately sends the second message to the first device to indicate that the reception is successful;

when the second device fails to receive all the transport blocks in the first number of transport blocks, the second device sends the second message to the first device to indicate that the reception fails.

5. The method of claim 4, further comprising:

and after the first equipment receives the second message which is sent from the second equipment and indicates that the receiving is successful, the first equipment immediately sends a new transmission block.

6. The method of claim 3, further comprising:

when the second device successfully receives all the transport blocks in the first number of transport blocks, the second device sends the second message to the first device to indicate that the reception is successful;

when the second device fails to receive any one of the first number of transport blocks, the second device sends the second message to the first device indicating a reception failure.

7. The method of claim 6, further comprising:

and when the first equipment receives the second message which is sent from the second equipment and indicates that the receiving fails, the first equipment retransmits the first quantity of transmission blocks.

8. The method according to any of claims 1 to 7, wherein the transmission time interval is 1 millisecond or 0.5 millisecond.

9. The method of any one of claims 1 to 7, wherein the first message is radio resource control signaling.

10. The method according to any one of claims 1 to 7, wherein the first device is a base station, the second device is a user equipment, and the first message is downlink control information.

11. The method according to any one of claims 1 to 7, wherein the first device is a user equipment, the second device is a base station, and the first message is an uplink scheduling request.

12. A transceiver in a first device of a wireless communication system for transmitting data to a second device, the transceiver being configured to transmit a first number of transport blocks per transmission time interval by the first device to the second device, wherein the first number is larger than 1; the transceiver is further configured to transmit, by the first device, a first message to the second device, wherein the first message is used to indicate whether the first number of transport blocks is the same or different and the first number.

13. A base station in a wireless communication system, wherein the base station comprises the transceiver of claim 12.

14. A user equipment in a wireless communication system, wherein the user equipment comprises the transceiver of claim 12.