Modulation Recognition System Implemention And Research Of Recognition Algorithm In Sdr Receiver

Software radio receiver which has both universal and open characteristics, but also has the advantages of standardization and networking, and the receiver based SDR can easily accomplish the adaptive tracking filter, digital multi-mode demodulation, and adaptive anti-jamming detection features, etc, has been used widely in the military communication.This paper presents a modulation recognition system composed of PC and FPGA hardware signal process platform, and completed the design and test of hardware platform, the design of control software based on PC, and USB communication interface driver. In the system, PC machine completes the program of user interaction, signal modulation recognition and communication with hardware platform by USB interface. The hardware platform has the function of high-speed analog-digital conversion, digital down conversion, data acquisition, multi-mode data demodulation and communication with the host computer through the USB interface which use the SX-55 FPGA belong to Xilinx for signal processing. The control software for user based on PC is design by LabVIEW, and USB driver and firmware code is developed by the C, recognition algorithm are developed in Matlab. The system for software radio receiver has the advantages of high processing speed, stable performance, good scalability, and algorithm updating easily, and widely application.In this paper, proposed PSK, FSK type signal recognition algorithm after analysis the characteristic of PSK type signal and the FSK type signal, simulation results show that the proposed recognition algorithm is feasible and effective. In the last, designing the signal recognition algorithm in control software based on MATLAB and LabVIEW interface.