Patent ID: 8040847

Claim:
A system comprising: an access point including a transceiver configured to communicate via a wireless network; and a mobile unit configured to communicate with the access point, the mobile unit including: a transceiver; and a channel estimation feedback encoder configured to: quantize a channel response function of a signal received from the access point or a residual value of the channel response function, wherein the channel response function is represented by M complex numbers, wherein a channel estimate is subtracted from the channel response function to provide the residual value; calculate a channel attenuation estimation to quantize the channel response function, wherein the channel attenuation estimation includes an estimate of time delay attenuation function of a magnitude of the time domain representation of the signal; de-quantize the quantized values of the channel response function and to use the de-quantized values to calculate the residual value of the channel response function; limit the channel response function to N complex numbers where N is less than M, wherein the N complex numbers are limited to values having time delays less than a predetermined delay spread; convert the signal from a frequency domain representation of the signal to a time domain representation of the signal prior to said quantizing; and generate a channel state information packet to be transmitted back to the access point, wherein the packet includes the quantized channel response function when the packet is a first feedback packet sent to the transmitter or a first feedback packet sent after a channel interruption, and includes the quantized residual value of the channel response function otherwise.