Estimation of the Parameters of an Unmodulated Carrier Signal Disturbed by Complex-Multiplicative and Additive Gaussian Noise

摘要

Estimation of the channel state and the parameters of a noisy unmodulated receiver input signal (pilot tone) is investigated for fast Rayleigh and Rician fading channels. The channel state is estimated by Kalman-filtering. Estimation of parameters, namely the frequency offset, the phase and the amplitude of the direct component at the time origin, the ratio of the power of the direct and the scattered component, and the fading bandwidth, is performed by maximum-likelihood-identification. This is applied to the design of a suboptimum phase locked loop, which makes use of the properties of the fading channel. Results are achieved analytically and by means of computer simulations.