Adaptive Digital Beam Forming using LMS Algorithm

There is a need of Phased Array Antennas in applications such as wireless communication, RADAR systems. The radiation pattern for this type of antenna has to be narrower sharper in one direction and should have nulls in other directions. In order to achieve this, phased array antennas are designed in such a way so as to steer the beam in required direction automatically. One of the techniques described in this paper is LMS algorithm. Nested LMS algorithms are used to optimize the radiation pattern. By varying the step-size, optimizing weights radiation patterns are observed. Change of direction of desired signal is also considered. It is observed that Gain is maximum in desired direction and nulls are created in the direction of noise signals.