Multi-antenna based DOA (direction of arrival) estimation and beam forming combined multipath signal receiving method

Abstract

The invention discloses a novel DOA (direction of arrival) estimation and beam forming combined multipath signal receiving method. The method includes: by the aid of the characteristic that spatial information carried in path signals in multipath signals is different and by combined application of DOA estimation and beam forming, processing the received multipath signals, effectively estimating an angle of arrival of each path signal, and distinguishing the path signals from the point of view of space; performing beam forming on the path signals of each angle so as to separate the path signals; extracting a main path signal from the path signals, and demodulating and decoding the main path signal. The core concept of the method is combined application of the DOA estimation and beam forming, the multipath signals are effectively separated, and a receiving end extracts the main path signal to have the same demodulated and decoded, thus impact of multipath effect is eliminated fundamentally, and receptivity of an OFDM (orthogonal frequency division multiplexing) communication system is improved.

Description

technical field [0001] The present invention relates to the technical field of mobile communication, and in particular to an application field of combined signal angle of arrival (Direction of Arrival, DOA) estimation and beamforming (Beamforming) technology when a multi-carrier system receives multipath signals. technical background [0002] In a wireless Orthogonal Frequency Division Multiplexing (OFDM) communication system, the actual communication environment is a multipath environment, and the radio waves of the transmitted signal will reach the receiving end through different paths, and the propagation delay and The fading is random, and the signal received by the receiving end is the superposition of multiple path signals. Multipath propagation will cause the OFDM signal to expand in the time domain waveform in the time domain and produce frequency selective fading in the frequency domain. At the same time, the relative movement between the nodes leads to the occurre...

AI Technical Summary

Problems solved by technology

Currently existing schemes are roughly divided into two categories: one is to use channel error correction codes, adaptive modulation and channel equalization techniques in wireless OFDM communication systems; among them, channel equalization techniques are to insert specific pilots into OFDM symbols when transmitting , the receiving end uses the inserted specific pilot to equalize the signal; channel error correction technology and channel equalization technology increase the channel overhead, and cannot completely eliminate the impact of frequency selective fading on transmission reliability; adaptive modulation technology in the deterioration of channel conditions When the modulation method with stronger anti-interference ability is selected, the channel utilization rate will also be reduced; the second is based on multi-antenna diversity reception technology, due to the irrelevance that may be generated by the same signal through multi-path propagation, the use of different spatial locations Multiple antennas receive a transmitted signal at the same time, and then synthesize or select a strong signal, but this technology cannot fundamentally eliminate the impact of multipath effects

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