The Research Of Doa Estimation In Smart Antenna

The smart antenna technology is one of the key technologies of the third generation mobile communication system, which is a hot research topic at home and abroad. The smart antennas receive the space division multiple access concept, differences in spatial location by the user of their separation. Therefore,each user's direction of arrival, as reflected in user-space location of an important parameter in smart antennas play a very important roll.This article discusses the status of array antenna technology, basic working principle, characteristics and advantages, through several DOA estimation algorithms commonly used in theoretical analysis and verification approach discussed their respective advantages and disadvantages, And, and analyzes the characteristics of the algorithm.The research work was implemented on MATLAB software platform. First, here introduces two kinds of traditional DOA estimation algorithm——Delay-sum method and Capon minimum variance method, through the simulation checks out their performance. Next, by analysis of a commonly used method——rotation-invariant sub-space algorithm (ESPRIT), And a deep research on two kinds of the improved algorithm, TLS_ESPRIT algorithm and SLS_ESPRIT algorithm. Through simulation, in high SNR, TLS_ESPRIT algorithm and SLS_ESPRIT performance of the algorithm is far higher than the basic ESPRIT algorithm. Especially in 4 the conditions, the improvement SLS_ESPRIT algorithm shows the optimal result, whether in low signal-to-noise ratio is high SNR performance is superior to other two algorithms. The detailed research on another very important high-resolution estimation algorithm -- multiple signal classification algorithm (MUSIC). On the analysis of the classical MUSIC to MUSIC after algorithm improved algorithm for root MUSIC -- and space smooth MUSIC algorithm is studied and the simulation. Simulation results show that the improved algorithm of two kinds of MUSIC with other algorithm has high precision, and its resolution is higher than other algorithms.