An improved carrier recovery method in multi-path fading channels for DTMB receivers

This paper presents an improved carrier recovery method for Chinese Digital Terrestrial Multimedia Broadcasting (DTMB) system especially in multi-path channels. The conventional methods are mostly derived from the AWGN channel model. In the real propagation environment, multi-path distortions are much more common, which may result the conventional carrier recovery loop locked at an undesired point. In this paper, an improved method using as many as observations of carrier frequency offset in one frame is introduced to reduce the estimated variances. Lab tests and Field trials have proved that it can dramatically reduce the probability of fake lock in real propagation environments.