Title :
HACT device applications
Author :
Cullen, Donald E. ; Grudkowski, Thomas W. ; Merritt, Sears W. ; Tanski, William J. ; Carroll, Roger D. ; Sacks, Robert N. ; Branciforte, Emilio J.
Author_Institution :
United Technol. Res. Center, East Hartford, CT, USA
Abstract :
Heterojunction acoustic charge transport (HACT) transversal filters have been successfully operated with a charge transport efficiency of 0.9996 for 6-μs devices and >0.9999 for 3.3 μs devices with uniform tap weighting. Device delays in excess of 10 μs should be possible. Results for HACT devices with apodized tap weights are presented and demonstrate accurate time and frequency response characteristics. Hamming filter sidelobes are close to theory. Phase weighting of HACT taps resulted in excellent device-matched filter response to a nested Barker code input. Transversal equalization or pulse sharpening, is demonstrated for an exponential input, reflecting the good baseband response of the device
Keywords :
acoustoelectric devices; frequency response; p-n heterojunctions; surface acoustic wave filters; ultrasonic delay lines; HACT devices; Hamming filter sidelobes; SAW; apodized tap weights; baseband response; charge transport efficiency; device-matched filter response; exponential input; frequency response characteristics; heterojunction acoustic charge transport devices; nested Barker code input; phase weighting; programmable filters; pulse sharpening; time response characteristics; transversal filters; uniform tap weighting; Acoustic devices; Band pass filters; Circuits; Delay; Electrodes; Filter bank; Geometry; Matched filters; Surface acoustic waves; Transversal filters;
Conference_Titel :
Ultrasonics Symposium, 1990. Proceedings., IEEE 1990
Conference_Location :
Honolulu, HI
DOI :
10.1109/ULTSYM.1990.171356
