Electromagnetic characterization of airborne radome of fighter aircraft for Multimode Radar applications

The multimode radar (MMR) on a fighter aircraft is the primary sensor for fire control applications. It is generally located in the front portion i.e. nose cone of the fighter aircraft. Hence, part or full of the nose cone of the aircraft is to be made an RF power transparent radome for the purpose of MMR. Thus the radome plays a dual role i.e. a part of airframe for aerodynamic and structural purpose and part of radar for passing the RF power with minimum loss and disturbance. Electromagnetic (EM) characterization of the radome on a fighter aircraft for its multimode radar application is an elaborate process since the EM measurements that are to be carried out on radome are very high in number. In addition to this the mechanical supporting structures and electrical equipment required adds further complexity to this task. Hence, the EM characterization facilities for radomes of fighter class aircrafts are very few in the country. If EM characterization is one complex task, the design and manufacturing of airborne radomes for fighter aircrafts, to meet the required EM specification of radar on the fighter, is another complex task by itself. This paper focuses on the EM characterization and the detailed steps involved in such procedures of radomes for fighter aircrafts in general and presents a case study of one such radome of Tejas aircraft for its multimode radar.