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>An adaptive algorithm for simultaneously canceling Doppler shift, amplitude jitter, and phase jitter in satellite and mobile communication systems.
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An adaptive algorithm for simultaneously canceling Doppler shift, amplitude jitter, and phase jitter in satellite and mobile communication systems.
This research investigates an adaptive algorithm for simultaneously canceling Doppler shift, amplitude jitter, and phase jitter in satellite and mobile communication systems.; A new adaptive algorithm for the Doppler canceller is discussed. For compensating the error in the phase domain a phasor LMS algorithm is developed. The algorithm is operated in a decision directed mode. The algorithm provides a very simple structure; it converges in a few symbols and is very attractive for real time signal processing and hardware implementation. Its steady state tracking performance and misadjustment are presented. The effect of amplitude jitter and phase jitter on the performance of the canceller is also presented.; An adaptive algorithm for the phase jitter canceller and the amplitude jitter canceller is presented.{09}It is shown that the heart of the algorithm is a 1-step predictor. This predictor is developed based on the adaptive line enhancer (ALE) technique. The performance of the cancellers is also presented.; A system of three cancellers, Doppler canceller, amplitude jitter canceller, and phase jitter canceller, cascaded one after another working independently for simultaneously canceling of Doppler shift, amplitude jitter, and phase jitter is presented. The optimal cancellation and the impact of the order of cancellations are presented. It is demonstrated that although there is nonlinear interaction among the transmission impairments during canceller operation, the system may nonetheless be designed as three independent canceller stages up to some limit in the amount of impairment. These design limits are presented.
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