Blind channel estimation: comparison studies and a new algorithm

Blind estimation techniques have the potential of significantly increasing the transmission efficiency for time-varying channels. A performance analysis of some blind channel estimation algorithms is presented. It is shown that ill-conditioned channels and the local minima of optimization techniques are the main causes of estimation error. To overcome these obstacles, a new optimization criterion that integrates two key aspects of the channel characteristics is introduced. Furthermore, the statistical characteristics of the channel are utilized by exploiting the principal component structures. The proposed algorithm based on this new criterion includes several existing algorithms as special cases. The new algorithm offers significant saving in computation and improvement in performance