Some issues of complexity and training symbol design for OFDM frequency offset estimation methods based on BLUE principle

In this paper we present reduced complexity OFDM frequency offset estimation methods based on the best linear unbiased estimation (BLUE) principle. Firstly, reduced complexity version of methods from (H. Minn and et al., 2002) is presented. Secondly, a method that possesses both slight performance improvement of (H. Minn and et al., 2002) and complexity advantage of (M. Morelli and U. Mengali, 1999) is proposed. Furthermore, we present the effects of the number of identical parts contained in the training symbol on the frequency offset estimation performance. Our results indicate that an improper choice of the number of identical parts contained in the training symbol can cause significant performance degradation to the methods of (M. Morelli and U. Mengali, 1999) and (H. Minn and et al., 2002) while a proper choice can give extra MSE improvement.