DESIGN OF A SPARSE ANTENNA ARRAY FOR COMMUNICATION AND DIRECTION FINDING APPLICATIONS BASED ON THE CHINESE REMAINDER THEOREM

In this paper we propose a sparse antenna array with nine elements for the integrated system of communication and direction finding. The main idea is that the sparse antenna array, whose element spacing is relatively larger than half wavelength, are divided into six two-element subarrays to transmit multi-beam. According to the spatial correlation characteristics of multi-beam, a packet exciting method employing multi-carrier Orthogonal Frequency Division Multiplexing (OFDM) signal is designed to modulate the directional information in to the signal space of subcarriers. In this way, a receiver with a single antenna can accomplish communication and direction-finding function by demodulation received signal. For the direction finding algorithm of the sparse antenna array, an approximate algorithm is designed to resolve the ambiguity problem based on the Chinese remainder theorem. Simulation results show that the proposed sparse antenna array can be applied to the integrated application of communication and direction finding.