FPGA implementation of automatic modulation recognition system for advanced SATCOM system

Automatic identification of the digital modulation type of asignal has found applications in many areas, including software defined radio (SDR), surveillance and threat analysis. This paper describes the FPGA based implementation of Automatic Modulation Recognition (AMR) algorithm foradvanced communication payload. A wavelet transform based algorithm which involves multi-rate signal processing, is realizedto distinguish QAM, PSK and FSK digital modulation signal in noisy environment. The approach is to use wavelet transform to extract the transient characteristics ina digital modulation signal to identify the type of modulation. The optimum thresholds are derivedfrom rigorous simulation in MATLAB/Simulinkunder the condition that the input noise is Additive WhiteGaussian (AWGN). The performance of the identification schemeis investigated through simulations. The design is implemented and tested in Xilinx Virtex-4 FPGA based card.