Active Q factor improvement of microstrip antenna

With recent developments in microwave communications, a great attention has been paid to “Active Microstrip Antennas”. For some specific applications, such as “Oscillating Active Integrated Antenna” [1][2], an active device functions as oscillator and the antenna plays the role of a resonator, furthermore the whole system coupled to another oscillating circuit presents better Q-factor qualifications. In this paper we present antenna application of “Negative Resistance Coupling” method which is usually used for active filters.