A mobile underwater acoustic communication method

Abstract

The invention provides a mobile underwater acoustic communication method, which generates the DPLFM signal required for communication, modulates the data to be transmitted, receives the signal through the mobile underwater acoustic communication channel at the receiving end, and performs virtual time reverse processing, and finally performs virtual time The inverted received signal is filtered and demodulated. The present invention uses the PLFM signal to replace the LFM signal as the carrier signal of the underwater acoustic communication system, and combines segmental linear frequency modulation and FDM technology to effectively improve the spectrum utilization rate and data rate of the traditional LFM underwater acoustic communication method; at the same time, When the relative motion speed of the communication transmitting end and the receiving end is low, the present invention does not need Doppler frequency shift compensation, and can be consistent with or even better than the performance of the OFDM underwater acoustic communication system with Doppler frequency shift compensation, and has the advantages of The advantage of simple algorithm.

Description

technical field [0001] The invention relates to the field of mobile underwater acoustic communication, in particular to related demodulation, segmented linear frequency modulation and other technologies, and is a relatively efficient mobile underwater acoustic multi-carrier communication method with low Doppler frequency shift and signal-to-noise ratio. Background technique [0002] Due to the existence of factors such as ocean currents and wind waves, there is often a certain relative speed between the transceivers in underwater acoustic communication. Therefore, the difference in propagation distance caused by movement causes the frequency and phase of the signal to change during transmission (ie Doppler frequency shift), and different from wireless communication, underwater acoustic communication often exists in wideband Doppler In addition to the frequency offset and phase shift, the signal also has the phenomenon of signal broadening or reduction. Therefore, the signal ...

AI Technical Summary

Problems solved by technology

However, due to the strong cross-correlation of LFM signals, the spectrum reuse rate of this method is low, and the bit error rate is relatively high when the system communication frequency band is relatively limited. The new signal whose cross-correlation is better than LFM can combine the idea of ​​frequency division multiplexing (FDM) to increase the data rate of LFM system in a limited frequency band

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