Device, system and method of uplink/downlink communication in wireless network

1. A wireless access point comprising:

a transmitter to transmit a downlink frame having a duration field value equal to or greater than a sum of: a time period corresponding to transmission of the downlink frame, a time period corresponding to transmission of an acknowledgement frame, a constant waiting period, and a backoff period calculated using a maximum contention window parameter.

2. The wireless access point of claim 1 , wherein the duration field value is equal to said sum.

3. The wireless access point of claim 1 , wherein the constant waiting period comprises a pre-defined Distributed Inter-Frame Space waiting period.

4. The wireless access point of claim 1 , wherein the backoff period comprises a time period including a number of time slots equal to a maximum size of the contention window.

5. The wireless access point of claim 1 , wherein the time period corresponding to transmission of the acknowledgement frame further comprises a Short Inter-Frame space waiting period.

6. A wireless communication system comprising:

a wireless access point to transmit a downlink frame having a duration field value equal to or greater than a sum of: a time period corresponding to transmission of the downlink frame, a time period corresponding to transmission of an acknowledgement frame, a constant waiting period, and a backoff period calculated using a maximum contention window parameter; and

a wireless communication station to receive the downlink frame from the wireless access point.

7. The wireless communication system of claim 6 , wherein the duration field value is equal to said sum.

8. The wireless communication system of claim 6 , wherein the station is to set a value of a Network Allocation Vector of the station to the value of the duration field of the downlink frame if the downlink frame is intended to be received by another station.

9. The wireless communication system of claim 6 , wherein the station is to maintain a value of a Network Allocation Vector of the station unmodified if the downlink frame is intended to be received by said station.

10. The wireless communication system of claim 9 , wherein the station is to decrement the value of the Network Allocation Vector of the station, and to transmit an uplink frame when the value of the Network Allocation Vector of the station reaches zero.

11. The wireless communication system of claim 10 , wherein the wireless access point is to receive the uplink frame, to transmit an acknowledgment frame, and to gain control of a wireless medium of the wireless communication system prior to another uplink transmission.

12. The wireless communication system of claim 11 , wherein the wireless access point is to transmit a subsequent downlink frame intended for reception by another station, the subsequent downlink frame having a duration field value equal to the duration field value of said downlink frame.

13. A method comprising:

transmitting a downlink frame having a duration field value equal to or greater than a sum of: a time period corresponding to transmission of the downlink frame, a time period corresponding to transmission of an acknowledgement frame, a constant waiting period, and a backoff period calculated using a maximum contention window parameter.

14. The method of claim 13 , comprising:

calculating the constant waiting period based on a pre-defined Distributed Inter-Frame Space parameter.

15. The method of claim 13 , further comprising:

maintaining unmodified a value of a Network Allocation Vector of a station if the downlink frame is intended to be received by said station.

16. The method of claim 15 , further comprising:

decrementing the value of the Network Allocation Vector of the station; and

transmitting an uplink frame when the value of the Network Allocation Vector of the station reaches zero.

17. The method of claim 16 , further comprising:

receiving the uplink frame;

transmitting an acknowledgrnent frame; and

gaining control of a wireless medium prior to another uplink transmission.

18. The method of claim 17 , further comprising:

transmitting a subsequent downlink frame intended for reception by another station, the subsequent downlink frame having a duration field value equal to the duration field value of said downlink frame.

19. The method of claim 13 , comprising:

calculating the constant waiting period based on a pre-defined Distributed Inter-Frame Space parameter.

20. The method of claim 13 , comprising:

calculating the time period corresponding to transmission of the acknowledgement frame taking into account a Short Inter-Frame Space waiting period.