Method and apparatus for transmitting and receiving data based on aggressive spatial reuse

• US 9,860,921 B2
• Filed: 02/10/2015
• Issued: 01/02/2018
• Est. Priority Date: 05/30/2014
• Status: Active Grant

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: Kim, Jin Kyeong, Jin, Sung Geun
• Primary Examiner(s): Javaid, Jamal
• Assistant Examiner(s): Khawar, Saad
• Application Number:
  US14/618,932
• Publication Number:
  US 20150351128A1
• Time in Patent Office: 1,057 Days
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 74/085 collision avoidance

Abstract

A method and apparatus for transmitting and receiving mobile data based on an ASR is provided. The mobile data transmission method of a first mobile terminal including transmitting a dRTS frame and creating an ASR list; performing channel access to a certain channel based on an ASR back-off process; transmitting an srDATA frame from the certain channel to a second mobile terminal based on the ASR list; and receiving an srACK frame from the second mobile terminal in response to the srDATA frame, wherein the certain channel is a channel to/from which a third mobile terminal transmits and receives a data frame, the srDATA frame and data frame are transmitted from the certain channel at a certain point, and the ASR list is information on a mobile terminal that does not collide with the data frame when the first mobile terminal transmits the srDATA frame and receives the srACK frame.

Claims

1. A mobile data transmission method of a first mobile terminal, the method comprising:

transmitting a first disruptive request to send (dRTS) frame through a certain channel in order to disrupt data transmission between a third mobile terminal and a fourth mobile terminal while a data frame is transmitted through the certain channel between the third mobile terminal and the fourth mobile terminal;

creating an aggressive spatial reuse (ASR) list that includes information on a second mobile terminal when it is determined that a collision does not occur in the data frame;

performing channel access to the certain channel based on an ASR back-off process, which is performed when the certain channel is busy;

transmitting a spatial reuse data (srDATA) frame through the certain channel to the second mobile terminal based on the ASR list; and

receiving a spatial reuse acknowledgement (srACK) frame for the srDATA frame from the second mobile terminal, depending on whether or not the second mobile terminal receives a second dRTS frame of a fifth mobile terminal communicating with a sixth mobile terminal, and

wherein when the second mobile terminal receives the second dRTS frame, the second mobile terminal does not transmit the srACK frame for the srDATA frame to the first mobile terminal.

2. The method according to claim 1,

wherein the method further comprises:

choosing a random number N (N is a natural number) from an ASR contention window and deciding an ASR back-off time;

measuring a noise power as the ASR back-off time decreases; and

performing the channel access when the noise power does not exceed a threshold value until the ASR back-off time decreases to 0.

3. The method according to claim 1,

wherein a first ending time at which transmission of the srDATA frame ends and a second ending time at which transmission of the data frame ends are set to be the same, and

wherein the srDATA frame comprises zero padded data when the second ending time is longer than the first ending time.

4. The method according to claim 3,

wherein information on the second ending time is obtained based on a duration field included in a request to send (RTS) frame that the third mobile terminal transmitted.

5. The method according to claim 1,

wherein when the first mobile terminal does not receive a response frame from a certain mobile terminal after the first mobile terminal repeatedly transmitted a frame to the certain mobile terminal a predetermined number of times, the ASR list is updated by deleting information on the certain mobile terminal when the ASR list includes the information on the certain mobile terminal.

6. The method according to claim 1,

wherein the transmitting a first dRTS frame and creating an ASR list by the first mobile terminal comprises:

determining whether or not a collision occurred in a data frame being transmitted from another mobile terminal due to the first dRTS frame; and

including the another mobile terminal into the ASR list when it is determined that a collision does not occur in the data frame.

7. The method according to claim 1, wherein whether the collision occurs or not is determined by checking whether the third mobile terminal receives an acknowledgement (ACK) frame from the fourth mobile terminal, or whether the third mobile terminal retransmits the data frame to the fourth mobile terminal, or both.

8. A first mobile terminal that transmits mobile data,

wherein the first mobile terminal comprises:

a radio frequency (RF) unit that transmits and receives a mobile signal; and

a processor that is selectively connected to the RF unit and operates,

wherein the processor is configured to;

transmit a first disruptive request to send (dRTS) frame through a certain channel in order to disrupt data transmission between a third mobile terminal and a fourth mobile terminal while a data frame is transmitted through the certain channel between the third mobile terminal and the fourth mobile terminal;

create an aggressive spatial reuse (ASR) list that includes information on a second mobile terminal when it is determined that a collision does not occur in the data frame,

perform channel access to the certain channel based on an ASR back-off process, which is performed when the certain channel is busy,

transmit a spatial reuse data (srDATA) frame through the certain channel to the second mobile terminal based on the ASR list, and

receive a spatial reuse acknowledgement (srACK) frame for the srDATA frame from the second mobile terminal, depending on whether or not the second mobile terminal receives a second dRTS frame of a fifth terminal communicating with a sixth mobile terminal, and

wherein when the second mobile terminal receives the second dRTS frame, the second mobile terminal does not transmit the srACK frame for the srDATA frame to the first mobile terminal.

9. The first mobile terminal according to claim 8,

wherein the processor is configured to choose a random number N (N is a natural number) from an ASR contention window and decide an ASR back-off time,

measure a noise power as the ASR back-off time decreases, and

perform the channel access when the noise power does not exceed a threshold value until the ASR back-off time decreases to 0.

10. The first mobile terminal according to claim 8,

wherein a first ending time at which transmission of the srDATA frame ends and a second ending time at which transmission of the data frame ends are set to be the same, and

wherein the srDATA frame comprises zero padded data when the second ending time is longer than the first ending time.

11. The first mobile terminal according to claim 10,

wherein information on the second ending time is obtained based on a duration field included in a request to send (RTS) frame that the third mobile terminal transmitted.

12. The first mobile terminal according to claim 8,

wherein when the first mobile terminal does not receive a response frame from a certain mobile terminal after the first mobile terminal repeatedly transmitted a frame to the certain mobile terminal a predetermined number of times, the ASR list is updated by deleting the certain mobile terminal when the ASR list includes the information on the certain mobile terminal.

13. The first mobile terminal according to claim 8,

wherein the processor is configured to determine whether or not a collision occurred in a data frame transmitted from another mobile terminal due to the first dRTS frame, and

wherein the processor includes the another mobile terminal into the ASR list when it is determined that a collision does not occur in the data frame.

14. The first mobile terminal according to claim 8, wherein whether the collision occurs or not is determined by checking whether the third mobile terminal receives an acknowledgement (ACK) frame from the fourth mobile terminal, or whether the third mobile terminal retransmits the data frame to the fourth mobile terminal, or both.