Design and Investigation of the Performance of Composite Spiral Antenna for Direction Finding Applications

Abstract

Antennas are very required elements in the safety and the security of the nation. During war times it is needed to identify the enemy targets. To obtain the enemies signal frequency and the polarization the defense antennas that are molded on to the airborne vehicles must be are to operating at a wide range of bandwidths with circularly polarized radiation patterns. These CP antennas were suitable at receiving ends for detecting any type of linearly polarized signals that are oriented in any direction. In this paper design and develop a composite spiral antenna covering a frequency range of 0.5−18 GHZ with the dimension of 90mm × 90mm is examined. The spiral antenna is a novel antenna of its kind for microwave direction finding as it exhibits wide frequency band. The Square spiral antenna is the best choice rather than a round spiral since it has reduced aperture. Spiral antenna has some inherent features like ultra wideband bandwidth, circular polarization and flush mounting capability. Hence these Spiral antennas suits as a best choice in direction finding applications. The design of composite spiral circuit is performed by using a computer program generated in MATLAB software. HFSS is a high performance full wave EM field simulator used to analyze the performance of spiral antenna in terms of its input reflection coefficient, Radiation pattern, gain and axial ratio in this paper. After the completion of the antenna design, its various parts are fabricated and assembled with precision. The assembled antenna is tested for various characteristics using network analyzer and anechoic chamber. The investigated outcomes of the tested Spiral antenna are projected in this paper.