Abstract: We present a kind of signal performance evaluation method for generic mismatch processing mode.On this basis,four reference modulations for compass B1 band interoperable signal are proposed,and within which,an optimal reference modulation is given based on the comprehensive performance.Compared with existing interoperable signals,the proposal modulation has independent intellectual property right.And it has superiorities in demodulation and tracking,as well as in the flexibility.The experimental results can be regarded as a feasible reference for the design and optimization of the compass signals.