Development of Microwave Ultrasonic Delay Lines

摘要

The report presents the theory, design and performance of microwave ultrasonic delay lines, and the results of investigations of related ultrasonic topics. The design considerations include specification and processing of delay materials, development of microwave ultrasonic thin-film transducers, studies of acoustic wave propagation, development of microwave networks for coupling to ultrasonic transducers, and design of delay line packages. Investigations are also reported of spurious suppression means and of power capability for ultrasonic delay lines. Prototype microwave ultrasonic delay lines were developed and delivered to specifications in the 500 to 2000 MHz frequency range with less than 36 db insertion loss over nominal 10 percent bandwidth, delay values from 0.3 to 3 microseconds, greater than 1 milliwatt output power, and spurious signals at least 20 db below the desired signal. The delay line packages are of shielded stripline construction, with a nominal volume of 1 cubic inch and weight of 6 ounces, suitable for operation over a large range of environmental conditions. Data on 12 delivered delay devices are reported, together with conclusions on the performance capabilities and limitations of microwave ultrasonic delay lines. (Author)