Blind algorithms for joint clock recovery and baseband combining in digital radio

A strategy is illustrated for joint space diversity baseband combining and timing recovery in microwave digital radio, based on a phase-independent criterion. The proposed receiver both provides a steady-state performance close to minimum mean square error receiver and solves the problems related to system synchronization, with an effective synergic action of clock recovery and adaptive baseband combining. The only multipath fading event which produces a (potential) system outage is given by two channels with only a slight difference in both notch frequency and notch depth. In this case, the post-combining equalizer is still able to equalize channels of moderate notch depth. The novelty of the present study is the joint application of the constant modulus algorithm to clock recovery and baseband combining. As a result, a significant immunity of the sampler/combiner on carrier phase is achieved