Maximum Likelihood Frequency Detectors for Orthogonal Multicarrier Systems

In this paper we derive a frequency estimation algorithm for a multicarrier system based o n the mazimum likelihood principle. We propose a frequency detector structure directly based on this algorithm and a reduced complezity structure having the same performance. However, such a detector shows a very small acquisition range due to the particular f o r m of the likelihood function f o r a multicarrier system. To overcome this limitation, we propose a modified version of the frequency detector which presents a considerably increased acquisition range together with a low augmentation i n complezity.