In an optically fed phased array antenna system, the microwave carrier signal is transmitted via a modulated lightwave to each active T/R (transmit/receive) module, where it must be converted back to the microwave domain. Currently, efficient optical-to-microwave conversion is extremely difficult, as the detected microwave signal is weak and noisy. A novel circuit, containing a high-gain/low-noise microwave injection-locked oscillator, has been developed to improve the interface between the optical and microwave components. The circuit utilizes two FETs and a dielectric resonator, which serves as a frequency-dependent feedback element. The circuit, designed to operate at about 8 GHz, provides significant amplitude and phase noise suppression. In addition, the circuit realization is compatible with MMIC technology. >

A double-stage injection-locked oscillator for optically fed phased array antennas

A novel circuit, containing a high-gain-low-noise microwave injection-locked oscillator, has been developed to improve the interface between the optical and microwave sub-assemblies of optically fed phased array antennas. The circuit utilizes two FETs and a dielectric resonator, which serves as a frequency-dependent feedback element. The circuit provides significant amplitude and phase noise suppression and is designed to operate around 10 GHz. The circuit realization is fully compatible with MMIC (monolithic microwave integrated circuit) technology. >

A MMIC based injection locked oscillator for optically fed phased array antennas

On radio science in Hungary

FM distortion in injection locked diode oscillators is investigated both theoretically and experimentally. At the lower frequency end of the locking band, the distortion is rather high. Hence the distortion is decreased with increasing frequency and a minimum is achieved at a frequency higher than the band center.

T. Berceli

Papers

FM Distortion in Single and Cascaded Injection Locked Diode Oscillators