Train-Carried Rail Signal Parameters Test System Based on Spectrum Correction Method and Virtual Instrumentation

A new test system is put forward to understand the FSK modulated track signal parameters in real time. The system model and design is based on the spectrum correction method. Carrier frequency is firstly identified by energy distribution in the frequency domain. Then, the signal is filtered and zoomed within a specific range centering on carrier frequency to obtain the spectrum lines. The frequency, amplitude and phase of each spectrum line are corrected using the centrobaric correction method. Lastly, signal parameters were calculated according to spectrum symmetry. Virtual instrumentation techniques were adopted during system implementation and software realization. The programming methodology is described in detail. Trial tests show that the test system is efficient and easy to use; all of the requirements are satisfied.