Improved Microwave Photonic Links via Receive-Side Nonlinear Signal Processing

We propose to significantly enhance the state-of-the-art of photonically-assisted microwave measurement and distribution systems by incorporating a highly efficient nonlinear optical process into the system design. The use of a nonlinearity can improve the dynamic range of the system without causing a reduction in the inherent noise-figure, thus eliminating a trade-off currently encountered when designing microwave-photonic systems. The photonic system will optically down-convert the microwave signal of interest thereby eliminating electronic mixers that can otherwise add loss, reduce dynamic range, and constrain the operating frequency range. Furthermore, we propose to exploit an emerging highly efficient modulator technology which is well suited to photonic integration. The expected net result is a high performance measurement of microwave signals over large frequency ranges (e.g. 10 - 100+ GHz) with low size, weight, and power. The systems will be well suited for integration into spacecraft as only a simple phase modulator is required at the antenna since almost all of the measurement apparatus can be connected to the modulator via low loss, low weight, and electro-magnetic interference free optical fiber.