The study of low temperature target weak signal detection technique based on power spectrum

The low temperature target radiation energy has smaller absolute-value and the signal is weaker. Meanwhile there are a lot of the noises such as temperature noise, thermal noise and so on. It is very difficult to be detected precisely if the conventional method is used. In this paper according to autocorrelation and power spectrum being a couple of Fourier transforms theory, power spectrum is used to realize autocorrelation calculation so that low temperature target weak signal is detected. Using the method can get autocorrelation function through calculating the value of power spectrum and the unknown weak signal amplitude is detected. The specific algorithm is given in this paper and the device of low temperature target weak signal detection is designed through embedded system ARM. The experimental waveforms and measurement results all show that the method is feasible to detect low temperature target weak signal. The digital detection of weak photoelectric signal is realized through using power spectrum to calculate autocorrelation.