Wavelet-denoising-based SC-FDE channel estimation method in short wave channel

Abstract

The invention discloses a wavelet-denoising-based SC-FDE channel estimation method in a short wave channel. The wavelet-denoising-based SC-FDE channel estimation method includes the steps of firstly, partitioning sent data, periodically inserting pilot frequency between data blocks, extracting information at the pilot frequency positions at a receiving end, and estimating channel frequency responses at the pilot frequency with an LS algorithm; secondly, carrying out IDFT on obtained estimation values to be in a time domain, factoring the estimation values in a wavelet domain according to a multi-Mallat algorithm, filtering out noise with a threshold denoising method, and reconstructing noise-eliminated signals; finally, carrying out interpolation zero filling on the reconstructed signals, carrying out DFT on the reconstructed signals to be in a frequency domain, accordingly obtaining all the channel frequency responses, and completing channel estimation. According to the wavelet-denoising-based SC-FDE channel estimation method in the short wave channel, the LS estimation left noise is eliminated with a wavelet denoising method, influences of the noise are further suppressed accordingly, the system bit error rate is lowered, and the system performance is improved.

Description

technical field [0001] The invention relates to the field of short-wave communication, in particular to an SC-FDE channel estimation method based on wavelet denoising under a short-wave channel. Background technique [0002] Short-wave communication relies on 1.5-30MHz electromagnetic waves for signal transmission. It is the earliest and widely used wireless communication method, and it is still an important means of medium and long-distance wireless communication. Short-wave communication relies on ionospheric reflection for communication. The channel conditions are harsh and channel characteristics change rapidly with time. At the same time, the short-wave channel is a multipath fading channel, and its multipath delay can reach 5ms. Multipath interference will cause intersymbol interference and frequency selective fading during data transmission, resulting in fluctuations in received signals and seriously affecting communication quality. Therefore, anti-multipath fading a...

AI Technical Summary

Problems solved by technology

[0006] For above deficiencies in the prior art, the object of the present invention is to provide a kind of SC-FDE channel estimation method based on wavelet denoising that solves that the existing LS channel estimation algorithm is greatly affected by noise and improves the estimation accuracy. The technical scheme is as follows: a SC-FDE channel estimation method based on wavelet denoising under a shortwave channel, which comprises the following steps:

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