Systems and methods for rate selection and resource unit allocation within a wireless local area network (WLAN)

1. A method for allocating a plurality of resource units among a plurality of client stations in a wireless local area network, the method comprising:

for allocating each resource unit:

estimating, at an access point (AP), a channel quality indicator for each of the respective channels between the AP and the plurality of client stations, the AP being configured to store a rate adaptation table, the rate adaptation table including:

a set of uplink receiver sensitivity measurement values;

an uplink transmission rate corresponding to each of the uplink receiver sensitivity measurement values;

a number of spatial streams corresponding to each of the uplink receiver sensitivity measurement values; and

a modulation and coding scheme corresponding to each of the uplink receiver sensitivity measurement values;

obtaining, at the AP, queue information indicative of data to be transmitted to the AP from each of the plurality of client stations;

computing, at the AP, a utility function indicative of the utility of transmitting data from the respective client stations as a function of the channel quality indicator and the obtained queue information; and

allocating the resource unit to a client station of the plurality of client stations having a highest value output by the respective utility function.

2. The method of claim 1 , wherein estimating the channel quality indicator for each of the respective channels between the AP and plurality of client stations comprises:

selecting, at the AP, a single-user transmission rate across the entire bandwidth indicative of a bit rate for transmitting data to a single client station communicating with the AP as a base rate;

identifying an uplink receiver sensitivity measurement corresponding to the single-user transmission rate from the rate adaptation table;

calculating a delta value indicative of a difference between the single-user transmission rate and an actual rate of transmission based on a channel state measurement, a size of the bandwidth, a size of the resource unit to be allocated, and

calculating an updated uplink receiver sensitivity for each resource unit as a function of the obtained uplink receiver sensitivity measurement and the calculated delta value; and

adjusting the base rate by mapping the updated uplink receiver sensitivity to the corresponding uplink transmission rate identified from the rate adaptation table.

3. The method of claim 1 , wherein obtaining, at the AP, queue information corresponding to each of the plurality of client stations comprises:

obtaining, at a wireless receiver of the AP, a data management packet from each of the client stations communicating with the AP, the data management packet comprising information about total needed transmission durations needed to empty respective queues corresponding to the respective client stations.

4. The method of claim 1 , further comprising:

temporarily allocating, by the AP, a resource unit to a client station corresponding to the highest utility value;

updating the channel quality indicator and the queue information after allocation of each resource unit and before allocation of the next resource unit;

determining whether an even-numbered resource unit of the plurality of resource units is allocated to a client station different from the client station assigned to the previous resource unit; and

in response to determining that an even-numbered resource unit is allocated to a client station different from the client station assigned to the prior resource unit, removing the client station assigned to the prior resource unit from consideration when subsequently allocating additional resource units.

5. The method of claim 1 , further comprising:

temporarily allocating, by the AP, a resource unit to a client station corresponding to the highest utility value;

updating the channel quality indicator and the queue information after allocation of each resource unit and before allocation of a next resource unit;

determining whether an odd-numbered resource unit is allocated to a client station different from the client station assigned to the prior resource unit,

in response to determining that an odd-numbered resource unit is allocated to a client station different from the client station assigned to the prior resource unit, removing both the client station assigned to the odd-numbered resource unit and the client station assigned to the prior resource unit from consideration when allocating additional resource units.

6. The method of claim 1 , further comprising:

temporarily allocating, by the AP, a resource unit to a client station corresponding to the highest utility value;

updating the channel quality indicator and the queue information after allocation of each resource unit and before allocation of a next resource unit;

determining whether an even-numbered resource unit and an immediately two prior resource units are allocated to the same client station;

in response to determining that the even-numbered resource unit and an immediately two prior resource units to the same client station, allocating the next resource unit to the same client station.

7. The method of claim 1 , further comprising:

temporarily allocating, by the AP, a resource unit to a client station corresponding to the highest utility value;

updating the channel quality indicator and the queue information after allocation of each resource unit and before allocation of a next resource unit;

determining whether an even-numbered resource unit and an immediately two prior resource units are allocated to the same client station;

in response to determining that the even-numbered resource unit and an immediately two prior resource units are allocated to the same client station, changing the allocation of the even-numbered resource unit to be assigned to different client station.

8. The method of claim 1 , further comprising:

temporarily allocating, by the AP, a resource unit to a client station corresponding to the highest utility value;

updating the channel quality indicator and the queue information after allocation of each resource unit and before allocation of a next resource unit;

determining, when a consecutive number of resource units starting from the first resource unit is allocated to a client station, whether the total number of resource units allocated to the client station is at least half of the entire bandwidth used by the AP; and

in response to determining that the total number of resource units allocated to the client station occupies at least half of the entire bandwidth:

allocating all available resource units in the bandwidth to the client station.

9. The method of claim 1 , further comprising:

temporarily allocating, by the AP, a resource unit to a client station corresponding to the highest utility value;

updating the channel quality indicator and the queue information after allocation of each resource unit and before allocation of a next resource unit;

determining, when a consecutive number of resource units starting from the first resource unit is allocated to a client station, whether the total number of resource units allocated to the client station is at least half of the entire bandwidth used by the AP; and

in response to determining that the total number of resource units allocated to the client station occupies less than half of the entire bandwidth:

removing the client station allocated to the odd-numbered resource unit from consideration when subsequently allocating additional resource units.

10. A wireless access point system for allocating a plurality of resource units among a plurality of client stations in a wireless local area network, the system comprising:

for allocating each resource unit:

an access point (AP) configured to:

estimate a channel quality indicator for each of the respective channels between the AP and the plurality of client stations;

obtain queue information indicative of data to be transmitted to the AP from each of the plurality of client stations;

compute a utility function indicative of the utility of transmitting data from the respective client stations as a function of the channel quality indicator and the obtained queue information;

allocate the resource unit to a client station of the plurality of client stations having a highest value output by the respective utility function; and

store a rate adaptation table, the rate adaptation table including:

a set of uplink receiver sensitivity measurement values;

an uplink transmission rate corresponding to each of the uplink receiver sensitivity measurement values;

a number of spatial streams corresponding to each of the uplink receiver sensitivity measurement values; and

a modulation and coding scheme corresponding to each of the uplink receiver sensitivity measurement values.

11. The wireless access point system of claim 10 , wherein the AP, when estimating the channel quality indicator for each of the respective channels between the AP and plurality of client stations, is further configured to:

select, at the AP, a single-user transmission rate across the entire bandwidth indicative of a bit rate for transmitting data to a single client station communicating with the AP as a base rate;

identify an uplink receiver sensitivity measurement corresponding to the single-user transmission rate from the rate adaptation table;

calculate a delta value indicative of a difference between the single-user transmission rate and an actual rate of transmission based on a channel state measurement, a size of the bandwidth, a size of the resource unit to be allocated;

calculate an updated uplink receiver sensitivity for each resource unit as a function of the obtained uplink receiver sensitivity measurement and the calculated delta value; and

adjust the base rate by mapping the updated uplink receiver sensitivity to the corresponding uplink transmission rate identified from the rate adaptation table.

12. The wireless access point system of claim 10 , wherein the AP, when obtaining, at the AP, queue information corresponding to each of the plurality of client stations, is further configured to:

obtain, at a wireless receiver of the AP, a data management packet from each of the client stations communicating with the AP, the data management packet comprising information about total needed transmission durations needed to empty respective queues corresponding to the respective client stations.

13. The wireless access point system of claim 10 , wherein the AP is further configured to:

temporarily allocate a resource unit to a client station corresponding to the highest utility value;

update the channel quality indicator and the queue information after allocation of each resource unit and before allocation of the next resource unit;

determine whether an even-numbered resource unit of the plurality of resource units is allocated to a client station different from the client station assigned to the previous resource unit; and

in response to determining that an even-numbered resource unit is allocated to a client station different from the client station assigned to the prior resource unit, remove the client station assigned to the prior resource unit from consideration when subsequently allocating additional resource units.

14. The wireless access point system of claim 10 , wherein the AP is further configured to:

temporarily allocate a resource unit to a client station corresponding to the highest utility value;

update the channel quality indicator and the queue information after allocation of each resource unit and before allocation of a next resource unit;

determine whether an odd-numbered resource unit is allocated to a client station different from the client station assigned to the prior resource unit,

in response to determining that an odd-numbered resource unit is allocated to a client station different from the client station assigned to the prior resource unit, remove both the client station assigned to the odd-numbered resource unit and the client station assigned to the prior resource unit from consideration when allocating additional resource units.

15. The wireless access point system of claim 10 , wherein the AP is further configured to:

temporarily allocate a resource unit to a client station corresponding to the highest utility value;

update the channel quality indicator and the queue information after allocation of each resource unit and before allocation of a next resource unit;

determine whether an even-numbered resource unit and an immediately two prior resource units are allocated to the same client station;

in response to determining that the even-numbered resource unit and an immediately two prior resource units to the same client station, allocate the next resource unit to the same client station.

16. The wireless access point system of claim 10 , wherein the AP is further configured to:

temporarily allocate a resource unit to a client station corresponding to the highest utility value;

update the channel quality indicator and the queue information after allocation of each resource unit and before allocation of a next resource unit;

determine whether an even-numbered resource unit and an immediately two prior resource units are allocated to the same client station;

in response to determining that the even-numbered resource unit and an immediately two prior resource units are allocated to the same client station, change the allocation of the even-numbered resource unit to be assigned to different client station.

17. The wireless access point system of claim 10 , wherein the AP is further configured to:

determine, when a consecutive number of resource units starting from the first resource unit is allocated to a client station, whether the total number of resource units allocated to the client station is at least half of the entire bandwidth used by the AP; and

in response to determining that the total number of resource units allocated to the client station occupies at least half of the entire bandwidth, allocate all available resource units in the bandwidth to the client station.

18. The wireless access point system of claim 10 , wherein the AP is further configured to:

determine, when a consecutive number of resource units starting from the first resource unit is allocated to a client station, whether the total number of resource units allocated to the client station is at least half of the entire bandwidth used by the AP; and

in response to determining that the total number of resource units allocated to the client station occupies less than half of the entire bandwidth, remove the client station allocated to the odd-numbered resource unit from consideration when subsequently allocating additional resource units.