On Frequency Offset Estimation Using the iNET Preamble in Frequency Selective Fading

This paper develops five data-aided frequency offset estimators for SOQPSK-TG equipped with the iNET preamble and operating in ISI channels. Four of the five estimators examined here are generalizations of frequency estimators developed for the AWGN channel. Simulations, performed over channel impulse responses measured in multipath scenarios encountered in aeronautical telemetry, show the modified L&R estimator is the best in terms of tracking range and achievable mean squared error. The D&M estimator is a close second and offers a computational complexity advantage in that it only requires the computation of one correlation value as opposed to the five correlation values required by the L&R estimator.