SBIR Phase I: Efficient Electro-Optical Modulators for Microwave-Photonic Links

This Small Business Innovation Research (SBIR) Phase I project is focused on developing a new type of lightwave transmitter based on the frequency modulation technique. Using the system FM (frequency modulation) gain to overcome the very high radio frequency (RF) insertion loss of optical fiber links, the transmitter should be able to achieve very low voltage operations (estimated to be 0.1V). Furthermore, the laser source and the equivalent modulator could be integrated in a small lightweight chip with a low production cost. The initial study has shown that it is possible to achieve >10 dB RF insertion gain at a 90 dB-Hz 2/3 and low noise. The result of this work will be the design and development of an integrated chip. With the successful development of the proposed modulator, it should be possible to manufacture very high bandwidth, high efficiency, low voltage?, and low RF insertion loss integrated laser/modulator devices. The outcome of the activity should lead to a marketable product covering the needs of both the military and commercial sectors. For military applications, low-loss RF signal transmissions, RF delay lines, and signal processing units would be the immediate target area of this application because of the great advantages of optical fibers in transmission bandwidth, immunity to electro-magnetic (EM) interference, and size as well as weight. The impact on commercial applications should result in, a low cost, high link budget analog AM CATV optical transmitter with more program channels (200 channels) based on this modulator technique. It could also serve metropolitan sized areas with more program channels and with lower operating and equipment costs.