Frequency hopping (FH) signal identification method

Abstract

The invention provides an FH signal identification method which is applied to a complex spacecraft detection site. Smooth pseudo Wigner distribution is used to identify FH signals in measurement and control communication of a spacecraft in a messy electromagnetic environment frequency spectrum. The method comprises the following steps that 1) input signals are divided to obtain a sliding overlap window, and smooth pseudo Wigner distribution is obtained; 2) an FH line of regression is obtained on the basis of smooth pseudo Wigner distribution, a quotient-difference algorithm is carried out on the FH line of regression to obtain abrupt change pulses; 3) according to the abrupt change pulses, the distance between the abrupt change pulses is calculated, and estimation of the FH period is obtained; and 4) parameter threshold iteration is carried out on the estimation of the FH period, and FH signals and frequency-fixed signals are identified. Thus, characteristic identification can be carried out on the weak FH signals under the low signal to noise ratio, and high identification rate can reached in -9dB and more.

Description

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AI Technical Summary

Benefits of technology

This patented method uses data from various sources such as radar or communication systems for identifying specific types of radio waves that may have been transmitted through space without interferenceing with each other's transmission paths. It achieves this by analyzing waveforms collected during these processes and comparing them against previously stored patterns made up of known signatures. By doing this, it allows users to identify which type of radiation they were trying to detect.

Problems solved by technology

This patented technical problem addressed in this patents relates to improving the accuracy of identifying and distinguishing between frequency hopped signals without relying solely upon timing characteristics like phase shifting keying (SPL).

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