A coherent optically controlled phased array antenna system

A true-time delay, optically controlled phased array antenna system whereby a large number (100-2500) of antenna elements can receive a series of microwave delays via use of a coherent optical carrier signal is described. Both transmit and receive antenna arrays are described, and the signal-to-noise ratio for a 128 channel system is calculated to be approximately 40 dB with an optical link loss of only approximately 3 dB for a 1 GHz instantaneous bandwidth at a wavelength of lambda 1.55 mu m. It is shown that the use of coherent optically controlled phased array antennas provides improved controllability and immunity from noise and system losses over other architectures currently being investigated.<
>