According to the special structure of unitary code, it is very simple to analyze the effect of fading correlation from the equation of PWEP.

Differential unitary space-time code(DUSTC) keeps good performance in rapidly fading channels when neither the transmitter nor the receiver knows the channel state information.

With the increase of the code rate, the production distance between the constellation of the unitary group code decreases rapidly and deteriorates the performance of the system.