A comparison of SNR estimation techniques for the AWGN channel

The performances of several signal-to-noise ratio (SNR) estimation techniqu es reported in the literature are compared to identify the "best" estimator . The SNR estimators are investigated by the computer simulation of baseban d binary phase-shift keying (PSK) signals in real additive white Gaussian n oise (AWGN) and baseband 8-PSK signals in complex AWGN, The mean square err or is used as a measure of performance, In addition to comparing the relati ve performances, the absolute levels of performance are also established; t he simulated performances are compared to a published Cramer-Rao bound (CRB ) for real AWGN and a CRB for complex AWGN that is derived here. Some known estimator structures are modified to perform better on the channel of inte rest. Estimator structures for both real and complex channels are examined.