Tunable pre-matching (TpM) transistor
Enabling & Support

Tunable pre-matching transistors

20/04/2017 328 views 1 likes
ESA / Enabling & Support / Space Engineering & Technology / Shaping the Future
 Programme:  TRP ITI  Achieved TRL:  4
 Reference:  B00016143  Closure:  2016
 Contractor(s):  FBH (DE), TU Darmstadt (DE), TESAT (DE)

 
Reconfigurable power amplifier systems, able to switch from one frequency band to another, can eliminate the need for additional hardware. This is particularly interesting for satellite applications where every gram in redundant hardware increase the overall system cost.

Design of a metal-insulator-metal  (MIM) varactor pair
Design of a metal-insulator-metal (MIM) varactor pair

Objectives
Develop a discrete tuneable pre-matching RF-Power transistor with a 20 W output power, tunability, and comparable Power Added Efficiency (PAE) to a non-tuneable transistor of similar type.

Achievements
Within this activity, an RF power varactor based on thick-film BST metal-insulator-metal (MIM) capacitors was developed. A novel varactor layout and material doping led to thermally stable, low-loss varactors. Furthermore, extensive modelling brought about an optimized mature design and a design process that enables package integration in a structured and predictable manner. This led to a successful demonstrator that met the stipulated specifications.

Package integration
Package integration

Benefits
A 20 W tunable pre-matching (TpM) transistor was demonstrated for the first time. It can be used in power amplifier designs to show the applicability in frequency agile system, dynamic load-modulated systems or in systems that need improved VSWR robustness. All of these properties would be very valuable for space applications. 

Further work
Based on this work an ARTES activity has been proposed. The intention of the follow-on activity is to extend the power range of this transistor and to demonstrate the use of a TpM transistor in a multi-band, multi-function power amplifier.