TABLE OF CONTENTS Pantelis K. Varlamos, Stelios A. Mitilineos, Stylianos C. Panagiotou, Apostolos I. Sotiriou, and Christos N. Capsalis
In this chapter, two methods for DOA estimation are presented. The first method resolves the two strongest signals in a wideband environment with their relative strengths, using the tool of genetic algorithms (GA) and a switched parasitic array (SPA) as a receiving antenna. The method concentrates on the two dominant paths, while incorporating the rest in the model as noise. It is based on the concept of electronic beam steering, and is mainly aimed at low-mobility applications [e.g., wireless local area networks (WLAN)]. The second method applies the MUSIC algorithm to SPAs, with appropriate modifications. The major change consists in the steering matrix, which corresponds to the different voltage patterns of the SPA. The specific method combines the high-resolution capability of MUSIC with the possibility of sampling the received signals with several radiation patterns generated by a SPA. Numerical results are presented to demonstrate both methods performances. Various SPAs and DOA distributions are selected, under different signal-to-noise ratios.
Recent research toward 3G and 4G wireless communications systems requires thorough knowledge of the basic propagation mechanisms in the mobile radio channel. One of the most important aspects into investigation is the estimation of the location of sources that transmit signals of interest. Hence, numerous direction-finding methods have been developed, which are useful in a variety of radar or sonar applications and location-based services (LBS) [1]. Moreover, direction-finding algorithms are deployed to locate the...
