Channel access mechanism for wide channels used in overlapping networks
View Patent ↗When a device is contending for the right to transmit on a wide channel (composed of a primary narrow channel and one or more secondary narrow channels), it may halt its backoff counter if one of the secondary channels is detected as busy, and restart the backoff counter from its halted value when all the channels are again detected as idle. Some embodiments may use a guard interval detection technique to aid in sensing whether the secondary channels are busy.
1. A method, comprising:
detecting that each narrow channel of a wide channel is idle;
starting a backoff counter subsequent to said detecting that each of the narrow channels is idle;
detecting, subsequent to said starting, that at least one of the narrow channels is busy;
halting the backoff counter in response to said detecting that said at least one of the narrow channels is busy;
detecting, subsequent to said halting, that each of the narrow channels is idle again; and
restarting the backoff counter from its halted value subsequent to said detecting that each of the narrow channels is idle again.
2. The method of claim 1 , further comprising:
detecting an expiration of the backoff counter; and
transmitting on the wide channel in response to said detecting the expiration.
3. The method of claim 1 , wherein said restarting the backoff counter comprises delaying by a distributed interframe space (DIFS) before said restarting.
4. The method of claim 1 , wherein said detecting that at least one of the narrow channels is busy comprises using a guard interval detection technique.
5. The method of claim 1 , wherein said detecting that each of the narrow channels is idle comprises using at least one of an energy detection technique and a preamble detection technique.
6. An apparatus, comprising:
a wireless communications device having a processor, a radio, and a backoff counter, the device to:
detect that each narrow channel of a wide channel is idle;
start the backoff counter subsequent to said detecting that each of the narrow channels is idle;
detect, subsequent to said starting, that at least one of the narrow channels is busy;
halt the backoff counter in response to said detecting that said at least one of the narrow channels is busy;
detect, subsequent to said halting, that each of the narrow channels is idle again; and
restart the backoff counter from its halted value subsequent to said detecting that each of the narrow channels is idle again.
7. The apparatus of claim 6 , wherein the device is further to:
detect an expiration of the backoff counter; and
transmit on the wide channel in response to said detecting the expiration.
8. The apparatus of claim 6 , wherein said restarting the backoff counter comprises delaying by a distributed interframe space (DIFS) before said restarting.
9. The apparatus of claim 6 , wherein said detecting that each of the narrow channels is idle comprises using a guard interval detection technique.
10. The apparatus of claim 6 , wherein said detecting that at least one of the narrow channels is busy comprises using at least one of an energy detection technique and a preamble detection technique.
11. The apparatus of claim 6 , further comprising an antenna coupled to the radio.
12. An article comprising
a computer-readable storage medium, wherein the medium is not a signal, that contains instructions, which when executed by one or more processors result in performing operations comprising:
detecting that each narrow channel of a wide channel is idle;
starting a backoff counter subsequent to said detecting that each of the narrow channels is idle;
detecting, subsequent to said starting, that at least one of the narrow channels is busy;
halting the backoff counter in response to said detecting that said at least one of the narrow channels is busy;
detecting, subsequent to said halting, that each of the narrow channels is idle again; and
restarting the backoff counter from its halted value subsequent to said detecting that each of the narrow channels is idle again.
13. The article of claim 12 , wherein the operations further comprise:
detecting an expiration of the backoff counter; and
transmitting on the wide channel in response to said detecting the expiration.
14. The article of claim 12 , wherein the operation of restarting the backoff counter comprises delaying by a distributed interframe space (DIFS) before said restarting.
15. The article of claim 12 , wherein the operation of detecting that at least one of the narrow channels is busy comprises using a guard interval detection technique.
16. The article of claim 12 , wherein the operation of detecting that each of the narrow channels is idle comprises using at least one of an energy detection technique and a preamble detection technique.