Abstract: In order to solve the problem that the randomness of the communication information will affect the radar performance and the signal with excessive peak average envelope ratio (PAPR) may lead to serious distortion at the radio frequency end in the integrated waveform design of radar communication based on orthogonal frequency division multiplexing, a waveform design method is proposed in this paper that uses non-orthogonal multiple access to separate the radar signal from the communication signal in the power domain to reduce the influence of the randomness of the communication information on the radar performance, and the active constellation map extension (ACE) is used to suppress the PAPR of the superimposed signal. Firstly, the reasons for the aliasing of superimposed constellations caused by the traditional power allocation principle are analyzed, and the optimal power allocation at different modulation orders is given. Secondly, the feasibility of ACE technology for PAPR suppression of superimposed signals is analyzed theoretically. Finally, the simulation results show that under different modulation modes and different signal-to-noise ratios, the high detection rate of radar signals and the minimum bit error rate of communication symbols can be achieved at the same time when the power allocation is optimal. The use of ACE technology not only ensures excellent radar performance and low bit error rate on the communication side, but also has a good suppression effect on the PAPR of superimposed signals.