A signal transmission model with gradient temperature was established on the basis of finite difference time domain(FDTD) method. And then

an iterative solution was applied to realize the signal transmission with different temperatures at different times. It shows that the time domain average voltage amplitude of output signal gradually attenuates with temperature rise

and at 573K the voltage amplitude is only about 90% of that of 303K

with the attenuation rate nearly 10%. The corresponding vibration test with gradient temperature was conducted. The power spectrum peak and time domain average voltage amplitude of output signal gradually reduce with temperature rise

which is consistent with the results of proposed model. The results of study will help to improve the accuracy of vibration test.