Recent advances in opto-electronic signal generation

In the past few years the application of optoelectronic techniques to microwave signal generation has culminated in the development of the opto-electronic oscillator (OEO). This unique device utilizes continuous light energy from a laser, in conjunction with an optoelectronic feedback loop including a long fiber delay, to produce high spectral purity signals at 10 GHz and higher. This performance is useful in a variety of communications and radar applications, but is particularly useful in photonic phased arrays. This is because the output of the OEO may be selected to be an electrical reference, or a high frequency reference modulated on an optical carrier. The latter configuration can provide for significant efficiency in photonic phased arrays, since otherwise a laser transmitter system would be required for the distribution of the electric signal. We have demonstrated the operation of OEO in several different configurations, previously. This includes the operation of a dual loop OEO, a coupled OEO (COEO), and an OEO based on an integrated laser/modulator device. In this paper we report on the demonstration of a compact 10 GHz OEO and its acceleration sensitivity performance. These latter results are of particular interest in applications with moving platforms. Finally we briefly describe our recent work towards the realization of an OEO on a chip