Narrow-band short-wave channel equalization algorithm under variable channel coefficient

Abstract

The invention relates to the technical field of short-wave data communication and specifically discloses a narrow-band short-wave channel equalization algorithm under a variable channel coefficient. The algorithm comprises the following specific steps: step 1) modeling a short-wave channel and performing initial estimation on the short-wave channel; step 2) utilizing a DDEA (data directed equalization algorithm) channel equalization algorithm to estimate the best estimation value of a user data sequence, and solving the user data sequence; step 3) performing short-wave channel tracking and solving the channel coefficient at any sampling time; step 4) utilizing a VCC-DDEA (variable channel coefficient-data directed equalization algorithm) to eliminate inter-symbol interference introduced in a training sequence and solving the best estimation value of the user data sequence under a time-varying channel; and step 5) amending user data which is estimated by the DDEA algorithm, further tracking the channel and amending a short-wave channel tracking value. The DDEA equalization algorithm using the variable channel coefficient to eliminate the inter-symbol interference introduced in the training sequence is adopted in the algorithm provided by the invention, thereby effectively improving the performance of narrow-band short-wave single-tone serial data communication and improving the signal-noise ratio by more than 5dB under the conditions of the same communication data rate and the same error rate.

Description

technical field [0001] The invention belongs to the technical field of short-wave data communication, and in particular relates to a narrow-band short-wave channel equalization algorithm under time-varying channel coefficients. Background technique [0002] The short wave mainly realizes beyond-the-line-of-sight communication by reflecting electromagnetic signals through the ionosphere. Because the ionosphere changes with time, place, season, climate, etc., the short-wave channel presents time-varying dispersion characteristics; the existence of multipath effects also leads to serious intersymbol interference. HF channel equalization is one of the effective means to overcome HF intersymbol interference and eliminate channel distortion. At present, the commonly used HF channel equalization algorithm is mainly based on the training sequence and frame data structure to eliminate inter-symbol interference DDEA (Data-Aided Equalization Algorithm) algorithm, which processes the c...

AI Technical Summary

Problems solved by technology

Because the ionosphere changes with time, location, season, climate, etc., the shortwave channel presents time-varying dispersion characteristics; the existence of multipath effects also leads to serious intersymbol interference

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