In this paper, we performance of frequency domain multiuser detector (FD-MUD) in [1] is analyzed over a Rician fading channel. The bit error probabilities for FD-MUD with coherent detection and differentially coherent detection are derived. The results are compared with those of decorrelating detector. Through numerical examples, it is shown Mat Me FD-MUD has lower bit error rate Man decorrealting detector over a Rician fading channel. It is also shown Mat Me FD-MUD has robustness to narrowband interference addition, advantages of the FD-MUD over decorrelating detector in implementation of detector are investigated.