The high PAPR is the major drawback of SFBC MIMO-OFDM systems to its practicability. To deal with this problem

a novel method was proposed to reduce the PAPR of SFBC MIMO-OFDM systems. It was called PIP（polyphase inversion and permutation） method. The method treated all transmit antennas as a whole. By dividing

rotating

and shifting the sequence twice

the method fully made use of the character of conjugation and shifting of all the antennas’ sub-carriers. Meanwhile

PIP method could reduce the complexity of calculation by using the character of IFFT. The simulation result proves the method to be efficient.