Multiple channel Vector Sum Phase Shifter Using Acousto-optic WDM

This paper proposes a novel technique to extend the capability of the vector sum phase shifter from a single channel to multiple channels for phased array antenna applications. Each channel is implemented using a distinct optical wavelength. Selective control of each channel is performed using an acousto-optic polarisation coupler. The concept is successfully demonstrated for two individually controlled channels. For each channel, a continuously variable frequency-linear phase shift is demonstrated between DC and 7 GHz with the phasing range exceeding 1000. It is anticipated that up to 10 channels could be simultaneously operated in a single device.