A Specific Combination Scheme for Modulation Identification of Mixed Modulation Signal

In this paper, the authors propose a specific combination scheme for modulation identification of a mixed modulation signal based on decision theory and tree classifier. In order to reduce the noise interference and improve the accuracy of modulation identification, they adopt the joint modulation signal characteristics with eigenvector made up of the number of subcarrier signal, the envelope variance of mean normalization and the statistical value of subcarrier signal instantaneous amplitude distribution in the identification of external modulation and internal modulation. The simulation results show that modulation identification ratio is close to 90% when the SNR is 6 dB. The proposed scheme outperforms the existing mixed modulation scheme.