Frequency synthesizers for airborne radars

The performance of multimode airborne radars has become increasingly dependent on the use of microwave synthesizers to generate the transmitted frequencies. The advantages of the use of multiple frequencies include reduced susceptibility to mutual interference, as well as improved detection capability when used in such applications as missile threat detection, ground mapping, and terrain follow/avoidance. A family of frequency synthesizers for airborne radars is considered. The use of common 'building blocks' for various applications allows rapid and cost effective response to quick reaction or low quantity applications. Rapid frequency switching is accomplished by appropriate combination of digital and analog techniques. The use of polyimide substrates is cost effective, although its relatively high loss may make it inappropriate for some applications.