SAW monolithic convolver structure with improved reproducibility

A single-plate SAW (surface acoustic wave) monolithic convolver structure is presented which retains the foldover and double transit suppression advantages of the parallel plate convolver by utilizing MSC-SBWCs (multistrip-coupler symmetric beamwidth compressors). Using this structure, a convolver with a 434-MHz center frequency, 100-MHz bandwidth, and 20 μs of processing time was designed and built. Included in the device design were periodically sampled dispersive transducers, MSC symmetric beamwidth compressors, parabolic horns, and monolithic resistors. An F-factor of -66 dBm and a foldover convolution greater than 42 dB down was achieved. Manufacturing advantages include easier fabrication of a period structure and single layer photolithography, SAW substrate mounting without a second dielectric substrate, and simple transducer tuning to achieve a better than 1.5:1 input voltage standing wave ratio