Design and development of 4 element linear microstrip patch antenna array with null steering by phase control

The paper presents design and development of a linear microstrip patch antenna array and also, a method to change the radiation pattern of the array by steering null in the desired direction. This is achieved by changing the phase of each of the array element which produces a null in the radiation pattern without significantly affecting the main beam lobe. Different methods can be used for array synthesis. In this paper the Schelkunoff polynomial method is used for the synthesis of array. For an N element array, (N-I) nulls can be formed. The array is designed around a frequency of 930 MHz using four microstrip patch antenna elements of rectangular shape arranged in linear configuration. The theoretical design of the antenna array is presented initially and then the results of the array simulation and the hardware implementation are presented.