Power saving method in wireless communication system
A method and apparatus of accessing a channel in a wireless local area network is provided. A destination station receives a request to send (RTS) frame to allocate a network allocation vector from a source station over a first bandwidth and transmits a clear to send (CTS) frame over a second bandwidth to the source station in response to the RTS frame. The second bandwidth is dynamically determined when a first parameter has a predetermined value.
1. A method of accessing a channel in a wireless local area network, comprising:
receiving, by a destination station, a request to send (RTS) frame to allocate a network allocation vector from a source station over a first bandwidth; and
transmitting, by the destination station, a clear to send (CTS) frame over a second bandwidth to the source station in response to the RTS frame,
wherein the second bandwidth is dynamically determined when a first parameter has a predetermined value, and
wherein the second bandwidth is indicated by a second parameter, the second parameter indicating one of four support modes of the second bandwidth, the four support modes including 20 MHz, 40 MHz, 80 MHz and 160 MHz.
2. The method of claim 1 , wherein the second bandwidth is equal to or less than the first bandwidth.
3. The method of claim 1 , wherein the first bandwidth is 20 MHz*N, where N is a positive integer.
4. The method of claim 1 , wherein the second bandwidth is 20 MHz*N, where N is a positive integer.
5. The method of claim 3 , wherein the first bandwidth is a bonded bandwidth of at least two 20 MHz when N is greater than one.
6. The method of claim 4 , wherein the second bandwidth is a bonded bandwidth of at least two 20 MHz when N is greater than one.
7. The method of claim 1 , wherein the first parameter indicates that a dynamic channel bandwidth allocation mode is supported if the first parameter has the predetermined value.
8. The method of claim 7 , wherein the first parameter is included in the RTS frame.
9. The method of claim 1 , wherein the second parameter is included in the CTS frame.
10. An apparatus of accessing a channel in a wireless local area network, the apparatus comprising:
a receiver configured to receive a request to send (RTS) frame to allocate a network allocation vector from a source station over a first bandwidth; and
a transmitter configured to transmit a clear to send (CTS) frame over a second bandwidth to the source in response to the RTS frame,
wherein the second bandwidth is dynamically determined when a first parameter has a predetermined value, and
wherein the second bandwidth is indicated by a second parameter, the second parameter indicating one of four support modes of the second bandwidth, the four support modes including 20 MHz, 40 MHz, 80 MHz and 160 MHz.
11. The apparatus of claim 10 , wherein the second bandwidth is equal to or less than the first bandwidth.
12. The apparatus of claim 10 , wherein the first bandwidth is 20 MHz*N, where N is a positive integer.
13. The apparatus of claim 12 , wherein the first bandwidth is a bonded bandwidth of at least two 20 MHz when N is greater than one.
14. The apparatus of claim 10 , wherein the second bandwidth is 20 MHz*N, where N is a positive integer.
15. The apparatus of claim 14 , wherein the second bandwidth is a bonded bandwidth of at least two 20 MHz when N is greater than one.
16. A method of accessing a channel in a wireless local area network, the method comprising:
receiving, by a destination station, a request to send (RTS) frame to allocate a network allocation vector from a source station over a first bandwidth, the RTS frame including bandwidth information indicating the first bandwidth and information indicating whether or not a dynamic channel bandwidth allocation mode is supported; and
transmitting, by the destination station, a clear to send (CTS) frame over a second bandwidth to the source station in response to the RTS frame,
wherein the second bandwidth is dynamically determined if the information indicates that the dynamic channel bandwidth allocation mode is supported, and
wherein the second bandwidth is less than the first bandwidth.
17. The method of claim 16 , wherein the first bandwidth is 20 MHz*N, where N is a positive integer.
18. The method of claim 16 , wherein the second bandwidth is 20 MHz*N, where N is a positive integer.
19. The method of claim 16 , wherein the first bandwidth is a bonded bandwidth of at least two 20 MHz when N is greater than one.
20. The method of claim 16 , wherein the second bandwidth is a bonded bandwidth of at least two 20 MHz when N is greater than one.
21. The method of claim 16 , wherein the CTS frame includes bandwidth information indicating the second bandwidth.
22. The method of claim 16 , wherein the second bandwidth is 20 MHz, 40 MHz, 80 MHz, or 160 MHz.