Monolithic Surface Wave Transversal Filter

SAW Programmable Matched Filter Signal Processor

“…& piezoresistive taps.1- 3 In the second development shift register and bucket brigade circuitry were added to control tap phase and amplitude. 4 - 7 The most recent development, described in this report, addressed the limitations uncovered in the previous programs. In order to realize the advantages of this potentially low-cost matched filter technology it was necessary on the third device development to make improvements in the following areas: 1) reduce the reflections of surface wave energy at the MOSFET detector taps due to the high profile of metal and oxide step regions, 2) improve the tap phase and amplitude control circuitry so that it could be microprocessor interfaced and would lead to overall programming speeds consistent with acoustic wave transit times and 3) improve the transducer quality and MOSFET tap detector efficiency.…”