An Anti-Jamming 5-Element GPS Antenna Array Using Phase-Only Nulling

This paper describes a GPS antenna array that is able to reject jamming signals from two different directions. The GPS array consists of five antenna elements of equal amplitude and different phases. The 5-element GPS array can produce two nulls using the phase-only technique. Ceramic substrate of high dielectric constant is used to realize a miniaturized GPS antenna element. Due to the narrow bandwidth of microstrip patch antennas printed on ceramic substrates, mutual coupling effect must be taken into account in the design of the 5-element GPS array. Closed-form solutions of the required phases to produce two nulls are obtained and given. Simulation results of the GPS antenna elements and arrays by Ansoft´s HFSS are also presented and discussed