The SAW-FET signal processor

The surface-acoustic-wave field-effect-transistor (SAW-FET) signal processor is an integrated device that couples a surface-acoustic-wave delay line to a multiplexed array of field-effect transistors. These signal processing devices can be used either as wideband analog buffer memories, as digitally programmable wideband transversal filters, or as wideband time-integrating correlators with low-speed readout. The implementation of two such SAW/FET devices is described: a ZnO/Si monolithic version and a LiNbO3/Si air-gap-coupled device. The operation of these devices is demonstrated in several of the various possible modes. A theoretical framework for evaluating their performance is provided, and the major considerations in device development are highlighted.