Sideband-information-free shallow sea underwater acoustic communication pattern selection peak-to-average ratio restraining algorithm based on frequency reversal mirror technology

Abstract

The invention provides a sideband-information-free shallow sea underwater acoustic communication pattern selection peak-to-average ratio restraining algorithm based on a frequency reversal mirror technology. At a data sending end, scrambling is carried out on data to be sent through M sets of different scrambling patterns, meanwhile, M sets of different comb-shaped pilot frequency positions are defined as signs, comb-shaped pilot frequency sequences are added to different pilot frequency positions to obtain candidate OFDM symbols, fast Fourier inversion is carried out on the candidate OFDM symbols to a time domain, and the symbol with the smallest peak-to-average ratio is selected as a transmission symbol; at a receiving end, fast Fourier inversion is carried out on received signals, frequency domain received information corresponding to the different comb-shaped pilot frequency positions is extracted to obtain pilot frequency domain response, matching pursuit is carried out on the pilot frequency domain reesponse, M sets of channel frequency domain response are restored, in frequency domain reversion, the cross correlation coefficients of the pilot frequency domain response and the channel frequency domain response is calculated, the value m corresponding to the maximum value in the M correlation coefficients is obtained, and finally descrambling is carried out through serial number information. The algorithm can guarantee the real-time performance and the reliability of an MIMO-OFDM underwater acoustic communication system.

Description

technical field [0001] The invention relates to a peak-to-average power ratio suppression method based on MIMO-OFDM underwater acoustic communication. Background technique [0002] The available bandwidth resources in underwater acoustic communication are very limited, which seriously limits the quality and rate of underwater acoustic communication. In this context, the OFDM technology with high spectrum utilization combined with the MIMO technology that can substantially increase the channel capacity without increasing the available bandwidth or increasing the transmission power has become a high-speed water channel technology in recent years. The new hotspot of acoustic communication. The shallow ocean acoustic channel is usually regarded as a slowly time-varying sparse channel, which can be described by a time-invariant filter. As a method for solving sparse solutions of linearly limited systems, compressed sensing can accurately recover sparse signals with a small amou...

AI Technical Summary

Problems solved by technology

[0004] Compared with the direct clipping method, although the PAPR suppression effect is slightly worse, this method has no bit error rate performance loss. The disadvantage is that multiple IFFT transformations are required, and the computational complexity is high.

In this way, a large amount of sideband information needs to be transmitted, resulting in a reduction in system communication efficiency and a waste of frequency bands.

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