Multi-path data signal joint judgment detection method

Abstract

The invention discloses a multi-path data signal joint judgment detection method, belongs to the technical field of signal detection in wireless communication, and provides a signal semi-blind detection method which is based on short-time Fourier transform and multi-channel diversity signal joint judgment under a short-wave channel, and is high in accuracy, and does not need channel prior information. Under the condition that a short wave channel only knows part of information of a sending end signal, the characteristics that the received multi-path signals carry the same information, statistics is independent and fading is irrelevant are utilized, and accurate detection and extraction of the signals can be achieved by applying a short-time Fourier transform means and a multi-path signal joint judgment method. Simulation results show that the algorithm can effectively and accurately detect the starting and ending positions of the signal under low signal-to-noise ratio and multipath frequency selective fading channels, and a detection effect superior to that of an energy entropy ratio detection method is obtained.

Description

technical field [0001] The invention belongs to the technical field of signal detection in wireless communication, and proposes a semi-blind signal based on short-time Fourier transform (DSTFT) and multi-channel diversity signal joint judgment with high accuracy and without channel prior information under a shortwave channel Detection method. Background technique [0002] The quality of short-wave communication is poor due to the influence of multipath delay, Doppler frequency shift and frequency selective fading in the channel. The existence detection of the signal is the premise of all subsequent processing, which is particularly important. In actual communication, the form of short burst signal and multi-channel diversity technology are often used to combat the bad channel transmission characteristics. The scheme of the present invention just utilizes the received diversity multi-channel data to complete the existence detection of the signal. [0003] Common and more mat...

AI Technical Summary

Problems solved by technology

This method is very sensitive to interference and nonlinear effects in adjacent frequency bands, and the detection structure requires large computational complexity and sufficient observation data, so it is not suitable for signal detection in the form of short bursts

The third type is the energy detection method, which distinguishes the signal and noise by the difference in a certain time-domain statistic, but this method is sensitive to noise and is not suitable for burst signal detection with low signal-to-noise ratio

That is to say, this method can reflect the characteristics of the signal in both time-frequency domains to a certain extent, but due to the constraints of the Heisenberg uncertainty principle, once the window function is selected, the time-frequency resolution will be determined, and it cannot be considered Frequency and Time Resolution Requirements

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