Conference Paper

UHF SSPA Design for WCDMA Space Applications

Lockheed Martin Commercial Space Systems, Newtown, PA, 18940, USA
DOI: 10.1109/MILCOM.2007.4455203 Conference: Military Communications Conference, 2007. MILCOM 2007. IEEE
Source: IEEE Xplore

ABSTRACT A new UHF Solid State Power Amplifier (SSPA) has been developed for a government mobile communications space program. The SSPA is capable of a peak power of 290 watts but will operate at a lower power of 135 Watts to provide the required linearity with WCDMA signals. Typical overall dc -RF efficiency is 42% at this operating point. The SSPA consists of an Input Amplifier with Command and Telemetry Electronics, a High Power Amplifier (HPA) section and an Electronic Power Converter (EPC). This paper begins by discussing the overall Satellite System Architecture, followed by details of the SSPA design and results from testing the Engineering Development Unit (EDU)

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