Discretized reactive loading based on switched stubs for null steering in Yagi-Uda arrays

This paper proposes a reactive loading configuration for effective null steering in Yagi-Uda array antennas. The system consists of switched transmission line stubs applied to the centers of the outermost director elements of the array. Good performance is achieved using 32 discrete susceptance values of relatively coarse resolution. Numerical simulations of the design suggest that potential null depths of 40 dB or more can be achieved across the entire sidelobe region of the testbed array.