METHOD AND DEVICE FOR TRANSMISSION OPPORTUNITY TRUNCATION

• US 20100135268A1
• Filed: 05/28/2009
• Published: 06/03/2010
• Est. Priority Date: 12/01/2008
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: SEOK, Yongho
• Granted Patent: US 8,223,639 B2
• Time in Patent Office: Days
• US Class Current: 370/338
• CPC Class Codes: H04W 74/002 Transmission of channel access control information
• CPC Class Codes: H04W 74/0816 with collision avoidance

Abstract

A method and device for communicating in a contention-based communication network. The method includes upon an early termination of a previously obtained transmission opportunity (TXOP) for communications with one of a mobile device and a base station, transmitting a contention free end (CF-End) frame to the base station for further broadcasting to the network by the base station. Also, a method and device for communicating in a contention-based communication system. The method includes receiving in a base station a first contention free end (CF-End) frame from a first mobile device indicating an early termination of a transmission opportunity (TXOP) previously obtained by the first mobile terminal for communications between the first mobile device and one of the base station and a second mobile device; and omnidirectionally broadcasting a second CF-End frame with a duration field having a value equal to zero.

Claims

1. A method of communicating in a contention-based communication network, comprising:

upon an early termination of a previously obtained transmission opportunity (TXOP) for communications with one of a mobile device and a base station, transmitting a contention free end (CF-End) frame to the base station for further broadcasting to the network by the base station.

2. The method of claim 1, wherein the CF-End frame includes a duration field having a value equal to a sum of a duration of one CF-End frame and a duration of a Short Inter-Frame Space (SIFS), the duration field corresponding to a truncated end time of the TXOP.

3. The method of claim 2, wherein the step of transmitting comprises:

transmitting the CF-End frame to the other device only if a sum of a duration of two CF-End frames and a duration of a Short Inter-Frame Space (SIFS) is less than a time remaining in the TXOP.

4. The method of claim 1, wherein the communications with the mobile device comprises:

transmitting via a directional antenna.

5. The method of claim 1, wherein the step of transmitting the TXOP contention free end (CF-End) frame to the base station comprises:

transmitting via one of an omnidirectional antenna and a directional antenna.

6. A method of communicating in a contention-based communication system, comprising:

receiving in a base station a first contention free end (CF-End) frame from a first mobile device indicating an early termination of a transmission opportunity (TXOP) previously obtained by the first mobile terminal for communications between the first mobile device and one of the base station and a second mobile device; and

omnidirectionally broadcasting a second CF-End frame with a duration field having a value equal to zero.

7. The method of claim 6, wherein the first CF-End frame includes a duration field having a value equal to a sum of a duration of two CF-End frames and a duration of a Short Inter-Frame Space (SIFS), the duration field corresponding to a truncated end time of the TXOP.

8. The method of claim 7, wherein the step of omnidirectionally broadcasting comprises:

omnidirectionally broadcasting the second CF-End frame only if the CF-End frame duration is less than a time remaining in the TXOP.

9. A terminal for communicating in a contention-based communication network, comprising:

a memory;

a RF unit; and

a processor operatively connected to the memory and RF unit,

wherein, upon an early termination of a previously obtained transmission opportunity (TXOP) for communications with one of a mobile device and a base station, the processor is configured to transmit a contention free end (CF-End) frame to the base station for further broadcasting to the network by the base station.

10. The terminal of claim 9, wherein the CF-End frame includes a duration field having a value equal to a sum of a duration of one CF-End frame and a duration of a Short Inter-Frame Space (SIFS), the duration field corresponding to a truncated end time of the TXOP.

11. The terminal of claim 10, wherein the processor is further configured to transmit the CF-End frame to the other device only if a sum of a duration of two CF-End frames and a duration of a Short Inter-Frame Space (SIFS) is less than a time remaining in the TXOP.

12. The terminal of claim 9, wherein the processor is configured to transmit with the mobile device via a directional antenna.

13. The terminal of claim 9, wherein the processor is configured to transmit via one of an omnidirectional antenna and a directional antenna.

14. A terminal for communicating in a contention-based communication system, comprising:

a memory;

a RF unit; and

a processor operatively connected to the memory and RF unit, the processor configured to

receive a first contention free end (CF-End) frame from a first mobile device indicating an early termination of a transmission opportunity (TXOP) previously obtained by the first mobile terminal for communications between the first mobile device and one of the base station and a second mobile device; and

omnidirectionally broadcast a second CF-End frame with a duration field having a value equal to zero.

15. The terminal of claim 14, wherein the first CF-End frame includes a duration field having a value equal to a sum of a duration of two CF-End frames and a duration of a Short Inter-Frame Space (SIFS), the duration field corresponding to a truncated end time of the TXOP.

16. The method of claim 15, wherein the processor is configured to omnidirectionally broadcast the second CF-End frame only if the CF-End frame duration is less than a time remaining in the TXOP.