Electronically Tunable Amplifier Technology

摘要

The development and design of an electronically tuned, frequency tracked filter pair based on a combination of classifical microwave filter cavity designs and an electronically tuned resonator design technique is described. The filters, consisting of a 100 watt two pole filter and a 1000 watt single pole resonator, are intended to be placed at the input and output of a frequency hopping UHF power amplifier to reduce the broadband noise and spurious signal outputs of the resulting electronically tunable amplifier. The improvement in EMC (electromagnetic compatibility) performance allows the amplifier to be used in colocation environments with other equipment. The design of each of the electronically tuned filters is based on a previously developed method of tuning a high power resonator with PIN diode switched capacitors. The correlation of the design of both the combline input filter and the coaxial resonator output filter to the electronically tuned resonator with the susceptance slope parameters required is developed with mathematical models presented in the report. The primary result of this research is the development of an experimental model filter pair which demonstrates the feasibility of operating at power levels compatible with a 1000 watt power amplifier and tuning within the 350 to 400 MHz band in less than 60 microseconds.