A Recognition Algorithm for Signal Modulation Modes of Tactical Data Link

The identification of the modulation mode is the key to the identification and differentiation of data link signals. In view of this, for the modulation modes (π/4-DQPSK, MSK, QPSK, 8PSK, BPSK, OQPSK) of the U.S. military Link-11, Link-16, Link-22 and CDL tactical data link signals, this paper proposes a tactical data link signal modulation recognition algorithm based on joint features. It mainly studies the extraction of four feature parameters of each modulated signal under Gaussian channels : high-order cumulant, square spectrum, fourth-order spectrum and high-order cumulant of differential signals. After that, several common tactical data link modulated signals are identified and classified by the decision tree. Finally, the simulation experiments shows that the algorithm has low computational complexity and high recognition rate, and has strong reliability and accuracy.