Improved modulation classification of MPSK signals based on high order cumulants

An improved modulation classification algorithm of MPSK signals based on high order cumulants is proposed and analyzed. Under the condition of unknown carrier frequency, first the constant amplitude and delayed complex conjugated multiplication is used to preprocess the original signal, then four order cumulants are exploited to construct the classified character. The unchangeness of classified character is proved in detail, and the robustness of the algorithm is analyzed aiming at short wave channels. Theoretical analysis and practical signal testing justify the effectiveness of the new algorithm.