Satellite TWT-amplifiers using the microwave power module conceptand radiation cooled collectors

摘要

Microwave Power Modules (MPM's) try to make the best use of thehigh power and high efficiency capability of Travelling Wave Tubes(TWT's) and of the low weight, high gain and excellent signal processingcharacteristics of the solid state MIC or MMIC Linearizer Front End(LFE) technology. The use of LFE's with satellite TWT's allows one toreduce the tube length and mass by about 30%, resulting in a short orSTWT of only 30 dB gain. The mass of the new Ku-band LFE is only 35 g.It has 1.3 W dc power consumption, 20 dBm output power and about 20 dBgain. Compared to standard TWT's, the third order intermodulationdistance of the LFE/STWT was improved by about 10 dB in backoff and 2 dBin saturation. The LFE is built in hybrid MIC and MMIC technology. TheSTWT had 62% efficiency over a 1.8 GHz bandwidth in Ku-band. Anextremely light weight Be-Cone radiation cooled collector for TWT's onDirect Broadcasting Satellites (DBS) was developed for further costsavings