This award is for the acquisition of a high performance spectrum analyzer. The analyzer will be used for interdisciplinary projects at UCSD involving lightwave components and system research, including in particular (a) massively parallel architectures for terabit packet switched photonic communication networks, (b) high frequency RF optical links (c) study of high frequency optoelectronic sample and hold circuits (c) planar, monolithic, and array integration of high performance photonic devices. These research projects, based on a synergy between optoelectronic device and network architectures, will lead to higher performance fiber optic communication networks. As the demands on networks and communications become ever greater with the advent of new applications such as animated visualizations and the necessity for the transfer of large amounts of data over networks arising from supercomputer outputs, it is becoming necessary to vastly increase the capacity to transmit and receive information. A particularly attractive transmission media is light which has an enormous capacity for transmitting data. The research supported by the acquisition of the high performance spectrum analyzer is in areas necessary for the realization of networks transmitting and receiving information at rates more than 1,000 billion bits/second. It includes both combined electrical/optical circuit research and research on protocols for routing packets of information through the network.