| The main studied topic of spatial spectrum estimation is the direction of arrival(DOA) of spatial signals. The MUSIC(multiple signal classification) algorithm, presented by Doctor R.O. Schmidt in 1979, is the most classical super-resolution algorithm. On the condition of exact model of antenna array, the MUSIC algorithm can estimate the DOA of uncorrelated signals accurately. However, as to correlated especially coherent signals and adjacent signals with small signal to noise ratio(SNR), MUSIC algorithm cannot estimate their DOA. In this paper, we have presented a modified MUSIC algorithm, which can estimate the DOA of coherent signals and adjacent signals with small SNR effectively. The detailed content of this paper is arranged as follow:1 Introduce the property of mobile communication channel, and discuss the interference and fading multipath that influence the quality and capacity of mobile communication.2 Presentation of the structure and principle of smart antenna, and concern the application of smart antenna to mobile communication.3 Introduce MUSIC algorithm, and then demonstrate its resolution ability to DOA of uncorrelated signals with computer simulation. At the same time, computer simulation results also show that MUSIC algorithm cannot estimate the DOA of coherent signals and adjacent signals with small SNR accurately.4 Put forward the modified MUSIC algorithm, and compare its resolution ability with MUSIC algorithm by computer simulation. The comparison results show that the modified MUSIC algorithm not can estimate the DOA of signals' that MUSIC algorithm cannot, but also can improve the estimation performance when estimating uncorrelated signals' DOA. |
