Efficient determination of a link performance parameter
View Patent ↗The subject matter disclosed herein provides methods and apparatus, including computer program products, for determining a link performance parameter, such as a supplemental channel characteristic of a wireless link. In one aspect, a base station receives packets from a client station. The base station determines a link performance parameter based on an error rate associated with reception of the packets. The base station then uses the link performance parameter to determine a modulation and coding scheme for use in transmitting packets to the client station. Related systems, apparatus and methods are also described.
1. A method implemented in a base station, the method comprising:
receiving a plurality of packet transmissions over a wireless uplink, at least one packet transmission including a downlink performance parameter;
determining, based on the packet transmissions, a plurality of uplink channel characteristic measurements, each uplink channel characteristic measurement being associated with one of the packet transmissions;
determining a predicted uplink channel characteristic based on the plurality of uplink channel characteristic measurements combined in a moving time weighted average and the downlink performance parameter; and
using the predicted uplink channel characteristic to determine a modulation and coding scheme for the wireless uplink.
2. The method of claim 1 , wherein determining the predicted uplink channel characteristic further comprises:
compensating the predicted uplink channel characteristic based on a time weighted error rate performance determined by multiplying a unitless weighting factor by a first quantity of packets successfully received without errors and dividing by a total quantity of packets received to determine a first result;
multiplying a quantity by a previously determined value of the time weighted error rate performance metric to determine a second result; and
subtracting the first result from the second result.
3. The method of claim 2 further comprising:
determining a supplemental channel characteristic parameter by multiplying a value range for the supplemental channel characteristic parameter by the time weighted error rate performance metric and adding thereto a bias value.
4. The method of claim 1 further comprising capping the predicted uplink channel characteristic based on a maximum value.
5. A method implemented in a base station comprising:
receiving packets through a wireless uplink;
determining a predicted uplink channel characteristic based on a plurality of uplink channel characteristic measurements combined in a moving time weighted average and a downlink performance parameter; and
compensating the predicted uplink channel characteristic based on information regarding successful reception of the packets as received by a receiving unit and a time weighted error rate metric; and
using the predicted uplink channel characteristic to determine a modulation and coding scheme for the wireless uplink.
6. The method of claim 5 , wherein compensating the predicted uplink channel characteristic further comprises:
determining a time weighted error rate performance metric by multiplying a unitless weighting factor by a first quantity of packets successfully received without errors and dividing by a total quantity of packets received to determine a first result;
multiplying a quantity by a previously determined value of the time weighted error rate performance metric to determine a second result; and
subtracting the first result from the second result.
7. The method of claim 6 further comprising:
determining a supplemental channel characteristic parameter by multiplying a value range for the supplemental channel characteristic parameter by the time weighted error rate performance metric and adding thereto a bias value.
8. The method of claim 5 further comprising capping the predicted uplink channel characteristic based on a maximum value.
9. A method implemented in a base station comprising:
transmitting a first set of packets through a wireless downlink;
receiving a second set of packets through a wireless uplink; and
determining a predicted uplink channel characteristic based on the plurality of uplink channel characteristic measurements combined in a moving time weighted average, a downlink performance parameter and information regarding successful reception of the first set of packets and a time weighted error rate metric.
10. The method of claim 9 further comprising:
selecting a modulation and coding scheme for the wireless uplink based on the predicted uplink channel characteristic.
11. The method of claim 9 , wherein determining the predicted uplink channel characteristic further comprises:
compensating the predicted uplink channel characteristic based on a time weighted error rate performance determined by multiplying a unitless weighting factor by a first quantity of packets successfully received without errors and dividing by a total quantity of packets received to determine a first result;
multiplying a quantity by a previously determined value of the time weighted error rate performance metric to determine a second result; and
subtracting the first result from the second result.
12. The method of claim 11 further comprising:
determining a supplemental channel characteristic parameter by multiplying a value range for the supplemental channel characteristic parameter by the time weighted error rate performance metric and adding thereto a bias value.
13. The method of claim 9 further comprising capping the predicted uplink channel characteristic based on a maximum value.
14. An apparatus comprising:
a transmitter configured to send packets over a downlink to an intended receiver; and
a modulation and coding selector configured to receive information regarding successful reception of the packets at the intended receiver, determine from the received information a predicted uplink channel characteristic based on a plurality of uplink channel characteristic measurements combined in a moving time weighted average and a downlink performance parameter, and use the predicted uplink channel characteristic to determine a modulation and coding scheme for an uplink.
15. The apparatus of claim 14 wherein the predicted uplink channel characteristic is capped based on a maximum value.
16. A non-transitory computer readable storage medium containing a first set of instructions adapted to create a processor, the processor being configured to implement a second set of instructions, the second set of instructions comprising:
a receiving code segment for receiving packets over a wireless uplink;
a link performance parameter determining code segment for determining, based on the packets, a predicted uplink channel characteristic based on a plurality of uplink channel characteristic measurements combined in a moving time weighted average and a downlink performance parameter; and
a transmission parameter determining code segment for determining a transmission parameter for the wireless uplink using the predicted uplink channel characteristic.
17. The non-transitory computer readable storage medium of claim 16 wherein the predicted uplink channel characteristic is capped based on a maximum value.
18. A non-transitory computer readable storage medium containing a first set of instructions adapted to create a processor, the processor being configured to implement a second set of instructions, the second set of instructions comprising:
a transmitting code segment for transmitting packets through a wireless downlink;
a link performance parameter determining code segment for determining a predicted uplink channel characteristic based on a plurality of uplink channel characteristic measurements combined in a moving time weighted average and a downlink performance parameter; and
a modulation and coding scheme determining code segment for determining a modulation and coding scheme for a wireless uplink using the predicted uplink channel characteristic.
19. The non-transitory computer readable storage medium of claim 18 wherein the predicted uplink channel characteristic is capped based on a maximum value.