Oscillator with photovaractor for optically-controlled phased-array antenna beam steering

The use of injection-locking to obtain the phase shifting for an array antenna transmitter is considered The general idea, described earlier by York and Itoh (see IEEE Trans. MTT, vol.46, no.11, p.1920-29, 1998) and by Qian and Itoh (see IEEE Trans. MTT, vol.46, no.11, p.1891-1900, 1998), consist in applying the tuning of the oscillator while it is injection-locked. In such a way it is possible to obtain the phase shift between the locking and output signals of the oscillator. It was shown that this solution could be improved with photonics with the use of the optical injection-locking and the optical tuning of the oscillator. Especially, the oscillator with a photovaractor can be useful, because optical locking and tuning can be applied with the use of the same laser diode and the optical fibre link.