DESIGN AND DEVELOPMENT OF A UNIT ELEMENT PLANAR FOLDED DIPOLE END-FIRED ANTENNA FOR AIRCRAFT COLLISION AVOIDANCE SYSTEM

Aircraft collision avoidance system is an airborne system which is designed to provide the service as a last defense equipment for avoiding mid-air collisions between aircraft. End-fired antenna is suitable to be used in such airborne systems where low aerodynamic drag is urgently required. An effort to develop such an antenna using dipole elements is presented in this paper. Here a unit element planar folded dipole antenna is presented which radiates in the end-fire direction. Split ring resonators inspired artificial materials are incorporated in the design to improve the directivity performance of the proposed antenna, and those materials are loaded in the same plane of the primary dipole radiator. Here suppression of surface wave in the antenna takes place, which results in gain enhancement and also reduction of side lobes which make radiation pattern better. All these proposed antennas are designed and simulated in CST Microwave Studio (MWS) EM tool which is based on time domain solver. The performance and other antenna characteristics have been explored from the simulation results followed by the antenna fabrication and measurement. Quite good agreement is achieved between the simulated and measured results. Much better performance characteristics make this proposed antenna a good candidate for this application.