Method, device, and system for transmitting data based on HARQ

• US 9,510,298 B2
• Filed: 11/14/2014
• Issued: 11/29/2016
• Est. Priority Date: 05/16/2012
• Status: Active Grant

• Current Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Inventors: Wu, Ye, Zhang, Wei
• Primary Examiner(s): Ngo, Ricky
• Assistant Examiner(s): SAMUEL, DEWANDA A
• Application Number:
  US14/542,381
• Publication Number:
  US 20150071267A1
• Time in Patent Office: 746 Days
• Field of Search: 370/336, 370/332, 370/318
• US Class Current: 1/1
• CPC Class Codes: H04B 17/24 with feedback of measurements to the transmitter
• CPC Class Codes: H04L 1/1893 Physical mapping arrangements physical resource mapping in general H04L5/00
• CPC Class Codes: H04L 5/0057 Physical resource allocation for CQI
• CPC Class Codes: H04W 52/241 taking into account channel quality metrics, e.g. SIR, SNR, CIR, Eb/lo
• CPC Class Codes: H04W 52/265 taking into account the quality of service QoS
• CPC Class Codes: H04W 52/48 during retransmission after error or non-acknowledgment
• CPC Class Codes: H04W 52/50 at the moment of starting communication in a multiple access environment
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 88/02 Terminal devices

Abstract

Embodiments of the present invention provide a method, a device, and a system for transmitting data based on a hybrid automatic repeat request (HARQ). The method includes: adjusting, according to current physical resources, a channel quality indicator (CQI) fed back by a terminal to obtain an adjusted CQI and determining an initial transmit power corresponding to the adjusted CQI; calculating an optimum number N_RV of redundant versions (RVs) according to a signal-to-noise ratio (SNR) gain, the adjusted CQI, and a requirement on quality of service of the terminal; adjusting the initial transmit power according to the optimum number of RVs and the adjusted CQI; and using N_RV transmit time intervals (TTIs) and the adjusted transmit power to transmit N_RV RVs of a transport block (TB) to the terminal. The embodiments of the present invention further provide a base station, a terminal, and a system for transmitting data.

Claims

1. A method for transmitting data based on a hybrid automatic repeat request (HARQ), the method comprising:

adjusting, by a processing device including at least one processor in a base station, according to current physical resources, a channel quality indicator (CQI) fed back by a terminal to obtain an adjusted CQI;

determining, by the processing device, an initial transmit power corresponding to the adjusted CQI;

calculating, by the processing device, an optimum number N_RV of redundant versions (RVs) according to the adjusted CQI, a requirement on quality of service of the terminal, and a signal-to-noise ratio (SNR) gain when the base station performs transmission by using an HARQ, wherein the SNR gain is determined according to a ratio of an SNR when the base station performs transmission without using the HARQ to an SNR when the base station performs transmission by using the HARQ, the optimum number N_RV is the number of RVs required by the base station to send a transport block (TB) to the terminal, and the optimum number N_RV is a natural number;

adjusting, by the processing device, the initial transmit power according to the optimum number N_RV, and the adjusted CQI to obtain an adjusted transmit power; and

sending, by a transmission device, N_RV RVs of the TB to the terminal by using N_RV transmission time intervals (TTIs) and the adjusted transmit power.

2. The method according to claim 1, wherein calculating the optimum number N_RV comprises:

determining, according to the adjusted CQI and a preset table of mappings between SNR gains and the numbers of RVs under different CQIs, the numbers of candidate RVs corresponding to energy-saving transmission of the terminal; and

determining the optimum number N_RV according to the requirement on quality of service of the terminal and the numbers of the candidate RVs.

3. The method according to claim 2, wherein when the requirement on quality of service of the terminal comprises a guaranteed bit rate (GBR) requirement and a delay requirement, determining the optimum number N_RV of RVs according to the requirement on quality of service of the terminal and the number of candidate RVs comprises:

using the following formula to calculate a filtering rate at a current TTI according to a filtering rate at a previous TTI, a preset length of a filtering window, a size of a transport block at the current TTI, and the number of the candidate RVs;

4. The method according to claim 3, wherein selecting the minimum value in the numbers of candidate RVs as the optimum number N_RV of RVs comprises:

selecting the number of candidate RVs, which corresponds to the maximum SNR gain, in the numbers of candidate RVs as the first number of candidate RVs from the numbers of candidate RVs, wherein the number of candidate RVs is the number of RVs that meets the condition that the filtering rate at the current TTI is greater than the preset threshold of the GBR requirement;

selecting the number of candidate RVs, which corresponds to the maximum SNR gain, in the numbers of candidate RVs as the second number of candidate RVs from the numbers of candidate RVs, wherein the number of candidate RVs is the number of RVs that meets the condition that the ratio of the data buffer size at the current TTI to the filtering rate at the current TTI is less than the preset threshold of the delay requirement; and

selecting the minimum value between the first number of candidate RVs and the second number of candidate RVs as the optimum number N_RV of RVs.

5. The method according to claim 1, wherein adjusting the initial transmit power according to the optimum number of RVs and the adjusted CQI comprises:

querying the preset table of mappings between the SNR gains and the numbers of RVs under different CQIs according to the optimum number of RVs and the adjusted CQI so as to acquire an SNR gain corresponding to the optimum number of RVs; and

using the following formula to adjust the initial transmit power according to the SNR gain corresponding to the optimum number of RVs;

6. The method according to claim 1, wherein before sending the N_RV RVs of the TB to the terminal, the method further comprises:

sending a notification signaling to the terminal at a TTI used to start HARQ transmission or at a TTI previous to the TTI used to start the HARQ transmission, wherein the notification signaling carries a modulation and coding manner, available bandwidth, a HARQ process identity of the HARQ transmission, a sequence for sending the RVs, and a TTI number of a response fed back by the terminal, and

wherein the TTI used to start the HARQ transmission is a first TTI used by the base station to send the RVs to the terminal.

7. A method for transmitting data based on a hybrid automatic repeat request (HARQ), comprising:

receiving an adjusted channel quality indicator (CQI) and an initial transmit power corresponding to an adjusted CQI, wherein the adjusted CQI and the initial transmit power are sent by a base station, and the adjusted CQI is obtained by the base station after adjusting a measured CQI according to current physical resources;

receiving an optimum number N_RV of redundant versions (RVs) calculated by the base station and an adjusted transmit power, wherein the optimum number N_RV of RVs is calculated and obtained by the base station according to the adjusted CQI, requirements on quality of service of a terminal, and a signal-to-noise ratio (SNR) gain when the base station performs transmission by using an HARQ, the adjusted transmit power is obtained by the base station by adjusting the initial transmit power according to the optimum number N_RV of RVs and the adjusted CQI, the SNR gain is determined according to a ratio of an SNR when the base station perfoinis transmission without using the HARQ to an SNR when the base station performs transmission by using the HARQ, the optimum number N_RV of RVs is the number of RVs required by the base station to send a transport block (TB) to the terminal, and N_RV is a natural number; and

sending the optimum number N_RV of RVs of the TB to the base station by using N_RV transmission time intervals (TTIs) and the adjusted transmit power.

8. The method according to claim 7, further comprising:

receiving, at a TTI previous to a TTI used to start HARQ transmission, a notification signaling sent by the base station and performing a data detection on corresponding physical resources according to the notification signaling, wherein the notification signaling carries a modulation and coding manner, available bandwidth, an HARQ process identity of the HARQ transmission, a sequence for sending the RVs, a start number of a TTI used for uplink transmission of the TB, and a TTI number of a response fed back by the base station, the start number of the TTI is notified by the base station, and

wherein the TTI used to start the HARQ transmission is a first TTI used by the terminal o send the RVs to the base station.

9. A base station, comprising:

a processor; and

memory coupled to the processor, the memory comprising instructions that, when executed by the processor, cause the base station to;

adjust, according to current physical resources, a channel quality indicator (CQI) fed back by a terminal to obtain an adjusted CQI and determine an initial transmit power corresponding to the adjusted CQI;

calculate an optimum number N_RV of redundant versions (RVs) according to the adjusted CQI, requirements on quality of service of the terminal, and a signal-to-noise ratio (SNR) gain when the base station performs transmission by using a hybrid automatic repeat request (HARQ), wherein the SNR gain is determined according to a ratio of an SNR when the base station performs transmission without using the HARQ to an SNR when the base station performs transmission by using the HARQ, the optimum number N_RVof RVs is the number of RVs required by the base station to send a transport block (TB) to the terminal, and N_RV is a natural number;

adjust the initial transmit power according to the optimum number N_RV of RVs and the adjusted CQI to obtain the adjusted transmit power; and

send the optimum number N_RV of RVs of the TB to the terminal by using N_RV transmission time intervals (TTIs) and the adjusted transmit power.

10. The base station according to claim 9, wherein the memory further comprises instructions that, when executed by the processor, cause the base station to:

determine, according to the adjusted CQI and a preset table of mappings between SNR gains and the numbers of RVs under different CQIs, the numbers of candidate RVs corresponding to energy-saving transmission of the terminal; and

determine the optimum number N_RV of RVs according to the requirements on quality of service of the tei iinal and the numbers of candidate RVs.

11. The base station according to claim 10, wherein when the requirements on quality of service of the terminal comprise a guaranteed bit rate (GBR) requirement and a delay requirement, the memory further comprises instructions that, when executed by the processor, cause the base station to:

use the following formula to calculate a filtering rate at a current TTI according to a filtering rate at a previous TTI, a preset length of a filtering window, a size of a transport block at the current TTI, and the number of candidate RVs;

12. The base station according to claim 11, wherein the memory further comprises instructions that, when executed by the processor, cause the base station to:

select the number of candidate RVs, which corresponds to the maximum SNR gain, in the numbers of candidate RVs as the first number of candidate RVs from the numbers of candidate RVs, wherein the number of candidate RVs is the number of RVs that meets the condition that the filtering rate at the current TTI is greater than the preset threshold of the GBR requirement;

select the number of candidate RVs, which corresponds to the maximum SNR gain, in the numbers of candidate RVs as the second number of candidate RVs from the numbers of candidate RVs, wherein the number of candidate RVs is the number of RVs that meets the condition that the ratio of the data buffer size at the current TTI to the filtering rate at the current TTI is less than the preset threshold of the delay requirement; and

select the minimum value between the first number of candidate RVs and the second number of candidate RVs as the optimum number N_RV of RVs.

13. The base station according to claim 9, wherein the memory further comprises instructions that, when executed by the processor, cause the base station to:

query the preset table of mappings between SNR gains and the numbers of RVs for different CQIs according to the optimum number N_RV of RVs and the adjusted CQI to acquire an SNR gain corresponding to the optimum number of RVs; and

use the following formula to adjust the initial transmit power according to the SNR gain corresponding to the optimum number of RVs;

14. The base station according to claim 9, wherein the memory further comprises instructions that, when executed by the processor, cause the base station to:

send, before sending the N_RV RVs of the TB to the terminal, notification signaling to the terminal at a TTI used to start hybrid automatic repeat request HARQ transmission or at a TTI previous to the III used to start the HARQ transmission, wherein the notification signaling carries a modulation and coding manner, available bandwidth, an HARQ process identity of the HARQ transmission, a sequence for sending the RVs, and a TTI number of a response fed back by the terminal, so that the terminal performs data detection on corresponding physical resources according to the notification signaling, and

wherein the TTI used to start the HARQ transmission is a first TTI used by the base station to send the RVs to the terminal.

15. A terminal, comprising:

a processor; and

memory coupled to the processor, the memory comprising instructions that, when executed by the processor, cause the terminal to;

receive an adjusted channel quality indicator (CQI) and an initial transmit power corresponding to the adjusted CQI, wherein the adjusted CQI and the initial transmit power are sent by a base station, and the adjusted CQI is obtained by the base station after adjusting a measured CQI according to current physical resources;

receive the optimum number N_RV of redundant versions (RVs) calculated by the base station and adjusted transmit power, wherein the optimum number N_RV of RVs is calculated and obtained by the base station according to the adjusted CQI, requirements on quality of service of the terminal, and a signal-to-noise ratio (SNR) gain when the base station performs transmission by using a hybrid automatic repeat request (HARQ), the adjusted transmit power is obtained by the base station by adjusting the initial transmit power according to the optimum number N_RV of RVs and the adjusted CQI, the SNR gain is determined according to a ratio of an SNR when the base station performs transmission without using the HARQ to an SNR when the base station performs transmission by using the HARQ, the optimum number N_RV of RVs is the number of RVs required by the base station to send a transport block (TB) to the terminal, and N_RV is a natural number; and

send N_RV RVs of the TB to the base station by using N_RV transmission time intervals (TTIs) and the adjusted transmit power.

16. The tee urinal according to claim 15, further comprising wherein the memory further comprises instructions that, when executed by the processor, cause the terminal to:

receive, at a TTI previous to a TTI used to start HARQ transmission, notification signaling sent by the base station and performing data detection on corresponding physical resources according to the notification signaling, wherein the notification signaling carries a modulation and coding manner, available bandwidth, an HARQ process identity of the HARQ transmission, a sequence for sending the RVs, a start number of a TTI used for uplink transmission of the TB, and a TTI number of a response fed back by the base station, the start number of the TTI is notified by the base station, and

wherein the TTI used to start the HARQ transmission is a first TTI used by the terminal to send the RVs to the base station.