The Direction Of Arrival Estimation And The Application In The Wireless Positioning

Spatial spectrum estimation is a very important research direction of array signal processing which develops based on spatial filtering and time domain spectrum estimation, and have excellent estimation performance and broad application prospect. The biggest characteristic of spatial spectrum estimation is algorithms, and estimate the signal direction of arrival based on algorithms. So in order to estimate the signal's arrival direction, we should understand the algorithms deeply, and in this basis ,to improve the algorithms. So, this paper analyzes and studies some of the classical algorithms, and does improvement according to the feature of the different array. The contents are as follows:Firstly, the paper gives the introduction of the background and significance of the research area as well as the history and the development now of spatial spectrum estimationSecondly, the basic principles of antennas are introduced including concepts, structures, classifications, the number of signals and so on. The reason of introducing the knowledge is in order to introduce the algorithms in the follow of this paper, and this knowledge air also the basis for achieving the effective DOA estimation;Thirdly, the paper focuses on the most common array-ULA. Making use of spatial spectrum estimation knowledge, the paper introduces several one-dimensional DOA estimation algorithms, and makes comparisons and analyses among different algorithms from the angles of noise ratio(SNR)and the number of array antenna;Fourthly, the paper proposes the DOA estimation base on two-dimensional of array-ULA, and verified the effectiveness of the algorithm through experiments, and compare the method in this paper and the method in the literature, verify the validity of the method in this paper;Fifthly, the paper also studies another important smart antenna array-UCA. In this paper describes the array of uniform circular array model, and propose the method that does not require array change based on the array-UCA, and through simulation experiments confirm the validity of this algorithm, and to verify this method can be estimated coherent signal sources;At last, the plan for next step is made based on the summarization of the paper.