The measurement system of frequency shift keying signal
Bao Cunhui (Department of Electrical Engineering,Shaanxi University of Technology,Hanzhong 723003,China)
To improve the accuracy of measuring track circuits FSK signal, a method was put forward by implemented with FPGA and ARM processor. The method was used to measure FSK signal period in real-time by quantization clock, and store the measurement data in dual-port RAM which was designed in FPGA, and then FPGA send measurement data via serial port module to ARM processor. By ARM processor, the main reasons for FSK measure errors were analyzed, and the distortion data in switching frequency was analyzed and compensated. The experiment results showed that this system not only has stronger anti-interference ability, but also can meet the high speed and accuracy requirement of industry.