Phase-only adaptive spatial transmit nulling

Adaptive phase-only transmit nulling was previously demonstrated using an eight-channel radar test bed. An error in the calibration software that left one of the transmit elements uncalibrated has since been corrected. New experimental results are presented that demonstrate improved performance relative to previous experiments. In this paper the Reiterative Uniform Weight Optimization (RUWO) algorithm, which utilizes the maximum signal-to-interference plus noise ratio (SINR) framework in a reiterative fashion, is used to generate adaptive phase-only weights from received interference data. Additionally, this work investigates the impact of the bandwidth of the interference signal on the ability to adaptively produce spatial nulls using RUWO.