Null steering, a comparative analysis

The topic "Null Steering" remains under research for more than two decades. Null steering finds its applications in RADAR, SONAR and Mobile communications. Many techniques have been developed which use various approaches / criteria to achieve good performance in null steering. Starting from very simple to complex, a large number of methodologies are available in literature. An algorithm with less computational complexity, deep null depth and narrow null width is preferable. In this paper, we present a comprehensive comparative analysis of the performance shown by the available major techniques for null steering. It is observed that Null Steering by real-weight control outperforms the other techniques like Null Steering in Phased Arrays by controlling the Element Positions, Real-time Null Steering by the CLEAN Technique and Null Steering Algorithm Based on Direction of Arrival Estimation. The observation is made on the basis of null depth, maximum number of nulls that can be steered, computational complexity and the side lobe levels.