Automatic broadband detection method based on dual fast Fourier transformation (FFT)

Abstract

The invention discloses an automatic broadband detection method based on dual fast Fourier transformation (FFT). The automatic broadband detection method comprises the steps as follows: FFT point numbers approximately needed by frequency spectrums with different resolutions are set according to a broadband detection requirement; sampling data of a point Nfft1 are obtained through using an analog to digital (A / D) collection card; signals equal to Nfft1 in length are respectively subject to one time of FFT at a point number of Nfft1 and K times of FFT at a point number of Nfft2, so as to obtain the frequency spectrums with the different resolutions; the frequency spectrums with the different resolutions are respectively subject to noise floor estimation and effective energy detection, so as to obtain frequency domains, time domains and energy characteristic parameters of the signals; and the detected effective energy is combined with a signal list, and then statistical characteristic parameters of the time domains and the frequency domains of the signals are obtained. The accuracy and the reliability of the automatic broadband detection method are obviously higher than the accuracy and the reliability of a detection algorithm using a fixed resolution, so that the automatic broadband detection method can adapt to frequency spectrum or signal supervision in a relatively complex electromagnetic environment.

Description

Technical field [0001] The invention relates to the field of radio monitoring, in particular to a broadband automatic detection method. Background technique [0002] With the continuous increase of wireless communication, the comprehensive monitoring and processing of aerial radio signals is also facing new challenges. The traditional working mode of narrowband scanning monitoring processing is no longer suitable for the needs of modern automatic processing procedures. Especially in the radio management and military reconnaissance departments, there is an urgent need for a method that can quickly and effectively automatically detect and discover signals in complex air environments. [0003] In order to quickly and effectively monitor and process airborne radio signals, it is basically first to obtain broadband time-domain data of airborne radio signals by using a broadband receiver, and then use digital signal processing technology to obtain the radio signal spectrum, and finally ...

AI Technical Summary

Problems solved by technology

[0007] Therefore, if the frequency spectrum is obtained through a fixed-length FFT transformation, the signal characteristic parameters detected and extracted are greatly affected by the FFT length, and it is difficult to ensure that these characteristic parameters can accurately and reliably reflect the true characteristics of the signal in both the time domain and the frequency domain.

In this way, it cannot adapt to the situation where there are both burst signals that require high time resolution and narrowband signals that require high frequency resolution.

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