Adaptive underwater sound decision feedback equalization method based on single vector sensor

Abstract

The invention discloses an adaptive underwater sound decision feedback equalization method based on a single vector sensor. The method comprises steps that, signal synchronization for a sound signal received by the vector sensor is carried out; electronic rotation synthesis is exerted on a horizontal vibration velocity signal, and then weight synthesis of the horizontal vibration velocity signal and a sound pressure signal is carried out to acquire a sound pressure and horizontal vibration velocity synthesis signal; the sound pressure and horizontal vibration velocity synthesis signal and a vertical vibration velocity signal are respectively demodulated to a base band, the base band signal is inputted to a decision feedback equalizer; a feed-forward end of the decision feedback equalizer is embedded with a phase-locked ring, an inputted base band signal firstly enters the phase-locked ring; equal-gain combination of the sound pressure and horizontal vibration velocity synthesis signal and the vertical vibration velocity signal is carried out; inter-code interference generated for a symbol in detection is estimated by a feedback filter and subtracts with output of a forward-direction filter to realize inter-code interference inhibition, and emission signal recovery is further realized. Through the method, an error rate can be reduced, and communication system robustness is improved.

Description

technical field [0001] The invention belongs to the field of underwater acoustic communication, in particular to an underwater acoustic adaptive decision feedback equalization method based on a single vector sensor. Background technique [0002] The vector hydrophone is a sound receiving transducer used to measure the underwater sound field vector (sound pressure gradient, particle velocity, acceleration, displacement or sound intensity). It consists of a concentric combination of sound pressure hydrophones and sensors that directly or indirectly measure vibration velocity. A single small-scale vector hydrophone can have an "8"-shaped or heart-shaped directivity that does not vary with frequency, so the vector sensor composed of it can obtain a more accurate vector sensor of the same size than a traditional sound pressure hydrophone. Great space gain. [0003] Decision Feedback Equalizer (DFE) is a nonlinear equalizer. Its basic idea is that once an information symbol is d...

AI Technical Summary

Problems solved by technology

[0004] Compared with the traditional sound pressure hydrophone, the vector sensor has many advantages, but there are few public reports on the application of the vector sensor in the field of underwater acoustic communication together with the decision feedback equalization method.

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