Noncoherent sequential dode acquisition based on a simple maximum likelihood ratio

Abstract

In this thesis, we consider noncoherent acquisition problems using sequential schemes. We study the conventional acquisition schemes using the maxi-mum likelihood estimate. Since the conventional scheme is hard to implement, practical schemes are proposed, which are approximations to the conventional one. The fixed-sample-size (FSS) test, sequential probability ratio test (SPRT), and truncated SPRT (TSPRT) are used for the decision process. The performance of the conventional and proposed code acquisition schemes are compared in additive white Gaussian noise and slowly-varying fading channels. Numerical results show that some of the proposed schemes have better performance than the conventional scheme.