Water sound OFDM communication system selectivity mapping peak-to-average ratio inhibition algorithm based on orthogonal pilot frequency sequences

Abstract

The invention provides a water sound OFDM communication system selectivity mapping peak-to-average ratio inhibition algorithm based on orthogonal pilot frequency sequences. Problems of adding of different orthogonal pilot frequency sequences to a sending end, the high peak mean value power ratio of an OFDM signal and the requirement of transmission of sideband information (SI) by use of the self correlation features are solved. By multiplying sending data with a scrambling phase position sequence and adding different orthogonal pilot frequency sequences, the peak to average power ratio of the OFDM signal is reduced. By using different orthogonal comb-shaped pilot frequency to mark the scrambling phase position sequence, and using the self correlation features of the orthogonal pilot frequency sequences on a receiving end, autonomous identification of the scrambling phase position sequence is achieved and selectivity mapping peak-to-average ratio inhibition without transmission of sideband information is achieved. According to the invention, the inhibition algorithm has better PAPR inhibition performance and perfect sideband information detection performance than a traditional algorithm; reliable water sound communication without sideband information is achieved; and efficiency and reliability of a communication system is effectively improved.

Description

technical field [0001] The invention relates to a selective mapping peak-to-average ratio suppression algorithm for an underwater acoustic OFDM communication system based on an orthogonal pilot sequence, belonging to an orthogonal frequency division multiplexing (OFDM) underwater acoustic communication system. 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. An important obstacle to the wide application of OFDM in underwater acoustic communication is its high PAPR defect. This defect will not only limit the efficiency of the transmitting system and reduce the signal-to-noise ratio of the received signal, but also cause signal distortion, cause nonlinear distortion, destroy subcarrier orthogonality, and reduce system performance. There are abundant literatures on the peak-to-average ratio suppression algorithm in radio OFDM co...

AI Technical Summary

Problems solved by technology

[0004] Compared with the simple clipping method, the SLM method will lose some PAPR suppression effect, but there is no bit error rate performance loss

Its disadvantage is that multiple IFFT transformations are required, and the calculation complexity is high, and in order to accurately restore the original data, it is necessary to accurately transfer the auxiliary information used by the transmitter to the receiver

In order to ensure the accuracy of the auxiliary information and avoid the catastrophe of full-symbol error, it is necessary to use multiple repeated transmissions, or to perform special encoding on the information, which will introduce a large amount of sideband information, resulting in a reduction in system communication efficiency and a wide range of frequency bands. waste of

Images