Optically fed aperture-coupled microstrip patch antennas

Several techniques are presented for feeding microstrip antennas with RF-modulated lightwave signals via an optical fiber. Lightwave-to-RF conversion is performed in a module containing a photodiode, RF circuitry, and a microstrip antenna element. Three different transmitting configurations at microwave frequencies were designed and tested: passive matching, matching with amplification, and an injection-locked oscillator. In each case, the only connections to the antenna modules were an optical fiber and DC bias lines