Patent ID: 7076001
Filing Date: 2006-07-11
Classification: H04B

Abstract:
1. A method for estimating a signal to noise ratio at a receiver of a transmitted signal having a modulated communication signal component including at least one data symbol and a noise signal component comprising the steps of: (a) receiving a transmitted signal having a real and an imaginary component; (b) sampling a predetermined attribute of the real component of the received signal to provide a first signal having a magnitude related to the attribute sampled; (c) sampling a predetermined attribute of the imaginary component of the received signal to provide a second signal having a magnitude related to the attribute sampled; (d) determining the power of the received signal from the first and second signals to provide a received power signal having a magnitude related to the power of the received signal; (e) producing a complex conjugate of the received signal to provide a conjugate signal; (f) delaying the conjugate signal by a predetermined length of time; (g) combining in a first predetermined manner the delayed conjugate signal with the received signal to thereby produce a combined signal; (h) sampling a predetermined attribute of an imaginary component of the combined signal to provide a communication power signal having a magnitude related to the power of the communication component of the received signal; (i) removing the modulation from the communication power signal; and (j) combining the received power signal and the communication power signal in a second predetermined manner to thereby provide an estimate of the signal to noise ratio of the transmitted signal.