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A beam switching array antenna for direction‐of‐arrival applications

In this article, a beam‐switching array antenna system is devised to estimate the direction‐of‐arrival (DOA) of radio frequency (RF) signals.The array contains 16 patch antennas arranged as a uniform circular array. In operation, four adjacent antenna elements are connected to RF tuners via RF switches to create a directive beam. By reconfiguring the switch setups, a rotating beam is produced to cover the azimuth plane. The angle of an incoming RF signal is estimated by processing the received signal strengths from the 16 beam setups via the curve‐fitting technique. Through measurements, the error in incident angle is found less than 3° with a simple estimation method. As the array antenna system is implemented with a receiver made of software‐defined radio, DOA estimation with more accuracy and multiple source monitoring are possible with more complicated signal processing techniques. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26036