A Direction Modulation Precise Wireless Transmission Scheme Based on Random Subcarrier Selection

Abstract

The invention discloses a direction modulation precision wireless transmission scheme based on the random subcarrier selection OFDM. The OFDM technology is used, and a base station randomly selects subcarriers corresponding to different frequency increments, performs up-conversion on expected signals, and sends the expected signals through an antenna array. A receiver performs down-conversion on the received signals, samples the signals to obtain a received signal sequence, performs discrete Fourier transform, and then restores the information through energy detection. By means of phase alignment / beam forming and artificial noise processing techniques, and by adoption of the phase alignment technology PAL, and the initial phases of the expected signals are designed, so that only the receiver is expected to obtain useful information; meanwhile, orthogonal artificial noise is designed, and the eavesdropping of the useful information by an eavesdropping machine is polluted. Compared with the traditional direction modulation, the direction modulation precision wireless transmission scheme has the advantages of breaking through the limitation of the emission angle dependent beams, realizing secure precision wireless transmission of distance- azimuth angle dependent beams and guaranteeing the security performance of the useful information to arrive at the expected receiver.

Description

technical field [0001] The present invention relates to the technical field of wireless communication, in particular to a direction modulation precise wireless transmission scheme based on random subcarrier selection OFDM. Background technique [0002] In recent years, the security of the physical layer of wireless communication has attracted widespread attention from academia and industry. Directional modulation is an effective physical layer transmission technology. Compared with traditional beamforming, its basic idea is to use beamforming and artificial noise. The processing means, in the desired direction, the constellation diagram of the received signal is consistent with the baseband signal, while the useful signal received in other eavesdropping directions is seriously polluted by noise so that the bit error performance deteriorates. [0003] Generally speaking, there are two main ways to realize the direction modulation technology of wireless communication at presen...

AI Technical Summary

Problems solved by technology

However, in a practical communication system, the eavesdropping receiver is likely not to transmit signals, which means that it is difficult to obtain the location information of the eavesdropping receiver

In addition, in actual scenarios, the eavesdropping receiver is most likely to have the same orientation angle as the desired receiver. At this time, the original DM system based on phased array design can no longer guarantee the safe transmission of the desired user.

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