Direction finding and isotropic reception gain with symmetric-pair antenna arrays

The process of matching an antenna array to a given wavefront would be considerably easier if the output signal of each array element, which in turn could well be a small sub-array, was just in phase or antiphase with a certain reference signal. This means that it would be possible to match the array (within certain limits) simply by the use of standard 180° phase shifters. By using a symmetric pair arrangement, it is possible to obtain signals which are essentially in phase or antiphase with each other. This property gives the output signals of a pair a binary character, which significantly simplifies the subsequent data acquisition and processing, and leads to various applications. In this paper, the principle of the symmetric pairs is explained as well as the use of the symmetric-pair concept for direction finding and isotropic reception gain