OSCILLATOR-TYPE ACTIVE-INTEGRATED ANTENNA - THE LEAKY-MODE APPROACH

This paper describes basic research carried out to design a microwave source module employing the concept of an active-integrated leaky-mode antenna. The novel active-antenna source module utilizes a microstrip as the radiating element while adopting uniplanar technology for the active circuit design, The microstrip is operated in the first higher order odd mode, which is a leaky mode, and excited by a proximity-coup led center-fed slotline on the same surface of the uniplanar microwave -integrated circuit. The measured performance of an X-band transmissio n-type injection-locked active-integrated antenna source module demons trated that such a design approach was suitable for linear array integ ration for quasi-optical power combining, The harmonic-balance (BOB) a nalysis of the proposed active-Integrated antenna agrees with the meas urements in both free-running frequency and power level. The measured radiation patterns of the active-integrated antenna also agree well wi th the theoretical predictions.