Rate adaptation for WiFi based wireless sensor devices

1. A method comprising:

storing parameters of communication packets successfully transmitted and received by a wireless device prior to turning off the wireless device;

comparing a first set of parameters of a current communication signal received after turning on the wireless device to the parameters of the received communication packets stored prior to turning off the wireless device;

identifying at least one received communication packet of the received communication packets stored prior to turning off the wireless device based on the comparison of the first set of parameters;

comparing a received signal strength indicator (RSSI) and carrier to interference-plus-noise ratio (CINR) of the current communication signal received after turning on the wireless device to an RSSI and CINR of the identified at least one received communication packet to identify a close received communication packet of the identified at least one received communication packet; and

identifying a communication rate for current packets communicated by the wireless device based on the comparison of the RSSI and CINR of the current communication signal to the RSSI and CINR of the identified at least one received communication packet.

2. The method of claim 1 , in which:

the first set of parameters comprise communication rates; and

comparing the first set of parameters further comprises comparing a communication rate of the current communication signal to the communication rates of the received communication packets to identify the at least one received communication packet.

3. The method of claim 1 , in which the stored parameters of the communication packets comprise a time a communication packet was transmitted/received, transmission rate for a communication packet transmission, an RSSI, a CINR, an indication of whether the communication packets are acknowledged and/or an indication of whether the packets were transmitted blindly.

4. The method of claim 1 , in which identifying the close received communication packet further comprises determining an absolute value of a difference between the RSSI and/or the CINR of the current communication signal and the identified at least one received communication packet.

5. The method of claim 4 , in which the close received communication packet comprises a smallest difference in RSSI and/or the CINR with respect to the current communication signal.

6. The method of claim 5 , further comprising calculating a difference between the RSSI of the identified close received communication packet and the RSSI of the current communication signal and calculating the difference between the CINR of the identified close received communication packet and the CINR of the current communication signal.

7. The method of claim 6 , further comprising selecting a greater of the absolute value of the difference in RSSI and the absolute value of the difference in CINR to determine a value of the RSSI or the CINR available for the current packets communicated by the wireless device.

8. The method of claim 1 , in which an initial communication packet of the stored communication packets successfully transmitted by the wireless device comprises a blindly transmitted packet.

9. The method of claim 8 , in which a communication rate for the blindly transmitted packet is increased to reduce a likelihood of packet transmission failure.

10. The method of claim 1 , in which the at least one received communication packet is received within a predetermined time after a packet of the transmitted communication packets is successfully transmitted by the wireless device.

11. The method of claim 10 , in which the packet of the transmitted communication packets is non-blindly transmitted by the wireless device.

12. The method of claim 1 , in which a received packet of the received communication packets is stored if received within a predetermined time after a packet of the transmitted communication packets is successfully transmitted by the wireless device.

13. An apparatus for wireless communication comprising:

means for storing parameters of communication packets successfully transmitted and received by a wireless device prior to turning off the wireless device;

means for comparing a first set of parameters of a current communication signal received after turning on the wireless device to the parameters of the received communication packets stored prior to turning off the wireless device;

means for identifying at least one received communication packet of the received communication packets stored prior to turning off the wireless device based on the comparison of the first set of parameters;

means for comparing a received signal strength indicator (RSSI) and carrier to interference-plus-noise ratio (CINR) of the current communication signal received after turning on the wireless device to an RSSI and CINR of the identified at least one received communication packet to identify a close received communication packet of the identified at least one received communication packet; and

means for identifying a communication rate for current packets communicated by the wireless device based on the comparison of the RSSI and CINR of the current communication signal to the RSSI and CINR of the identified at least one received communication packet.

14. The apparatus of claim 13 , in which:

the first set of parameters comprise communication rates; and

the means for comparing the first set of parameters further comprises means for comparing a communication rate of the current communication signal to the communication rates of the received communication packets to identify the at least one received communication packet.

15. The apparatus of claim 13 , in which the parameters of the communication packets comprise a time a communication packet was transmitted/received, transmission rate for a communication packet transmission, an RSSI, a CINR, an indication of whether the communication packets are acknowledged and/or an indication of whether the packets were transmitted blindly.

16. An apparatus for wireless communication, comprising:

a memory; and

at least one processor coupled to the memory and configured:

to store parameters of communication packets successfully transmitted and received by a wireless device prior to turning off the wireless device;

to compare a first set of parameters of a current communication signal received after turning on the wireless device to the parameters of the received communication packets stored prior to turning off the wireless device;

to identify at least one received communication packet of the received communication packets stored prior to turning off the wireless device based on the comparison of the first set of parameters;

to compare a received signal strength indicator (RSSI) and carrier to interference-plus-noise ratio (CINR) of the current communication signal received after turning on the wireless device to an RSSI and CINR of the identified at least one received communication packet to identify a close received communication packet of the identified at least one received communication packet; and

to identify a communication rate for current packets communicated by the wireless device based on the comparison of the RSSI and CINR of the current communication signal to the RSSI and CINR of the identified at least one received communication packet.