Apparatus for detecting weak signal based on time-frequency transformation

Abstract

The invention relates to a weak signal detection device based on time frequency conversion, which comprises a signal channel unit, an analog-digital conversion unit and a processor. A modulated signal to be tested is inputted into the signal channel unit for amplification and filtering by the signal channel unit; the analog-digital conversion unit outputs a quantized signal after sampling the analog signal outputted by the signal channel unit; the processor receives the quantized signal outputted by the analog-digital conversion unit and converts the quantized signal into a frequency domain signal for power spectral analysis, thereby obtaining the measuring results. The small signal detection device adopts the processor which converts the time domain signal into the frequency domain signal to detect the weak signal in the frequency domain and obtain the measuring results without a device producing a specific reference signal, thereby bringing about simple hardware structure and low cost.

Description

Technical field: [0001] The invention relates to a weak signal detection device, in particular to a weak signal detection device based on time-frequency transformation. Background technique: [0002] Weak signal detection is a cutting-edge field in measurement technology. Generally, sensors are used for power conversion to convert the detection object into power. When the useful signal is covered by a large amount of noise, the measurement is greatly limited. The main means of weak signal detection is to improve the signal-to-noise ratio of the signal. At present, the method of weak signal detection technology is through the lock-in amplification method, and the lock-in amplification method is divided into a digital lock-in detection method and an analog phase-lock detection method. The device for detecting weak signals by using the analog phase-locking detection method is mainly composed of a signal channel unit, a reference unit, a phase-sensitive detection unit, an anal...

AI Technical Summary

Problems solved by technology

[0004] Although the device for detecting weak signals using digital phase-locking detection method and analog phase-locking detection method can realize the detection of weak signals, the system hardware is relatively complicated. No matter the analog phase-locking method or the digital phase-locking method, not only the processing of the signal channel is required , it is also necessary to generate a specific reference signal through some methods

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