VSWR-protected 90 W L-band AlGaN/GaN power amplifier
VSWR-protected 90 W L-band AlGaN/GaN power amplifier
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VSWR 保护 90 W L 波段 AlGaN/GaN 功率放大器
DOI：
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发表时间：
2014
期刊：
影响因子：
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通讯作者：
F. V. van Vliet
中科院分区：
文献类型：
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作者：
M. van Heijningen;G. van der Bent;E. van der Houwen;A. Chowdhary;F. V. van Vliet
固态功率放大器需要防止负载失配引起的输出端反射功率。保护的标准方法是在输出端包括一个基于铁氧体的隔离器。隔离器将所有反射功率重定向到耗散负载电阻，并确保放大器的输出始终看到50 Ω负载。这种隔离器的缺点是尺寸大、重量重以及集成和小型化的可能性有限。在这项工作中，提出了一种保护电路，可以取代隔离器，仍然提供充分的保护，防止任何功率反射在输出的放大器。该保护电路基于反射功率的测量和反馈环路来调整驱动级的增益，也称为折返保护。驱动级和输出级采用AlGaN/GaN MMIC和功率棒技术实现。该保护电路已在一个2级、90 W L波段功率放大器上得到验证，该放大器将用于各种空间应用的卫星有效载荷。
Solid-state power amplifiers need protection against reflected power at the output caused by load mismatch. The standard method for protection is to include a ferrite-based isolator at the output. The isolator will redirect all reflected power to a dissipating load resistor and will ensure that the output of the amplifier always sees a 50 Ω load. Disadvantage of such isolator is the large size, weight and limited possibility for integration and miniaturization. In this work a protection circuit is presented that can replace the isolator and still offer full protection against any power reflection at the output of the amplifier. This protection circuit is based on measurement of the reflected power and a feedback loop to adjust the gain of a driver-stage, also known as fold-back protection. The driver-stage and output stage are implemented in AlGaN/GaN MMIC and power-bar technology. This protection circuit has been demonstrated on a 2-stage, 90 W L-band power amplifier, intended to be used in satellite payloads for various space applications.