Highly robust microwave low-noise amplifiers

高度稳健的微波低噪声放大器

• 批准号: 387060302
• 负责人: Professor Dr.-Ing. Wolfgang Heinrich
• 金额: --
• 依托单位: Department Mikrowellentechnik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2017
• 资助国家: 德国
• 起止时间: 2016-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/387060302?language=en
• 关键词: Highly; robust; microwave; low; noise

The first component of a radio receiver that follows the antenna is commonly the low-noise amplifier (LNA). It is required to amplify the usually very weak signal to a power level high enough to ignore any additive noise of subsequent electronic stages. Therefore, an LNA is a very sensitive low-power component. However, a radio receiver usually also reveceives more signals than just the intended one. If a powerful transmitter is nearby, the power level easily exceeds the average receiver power level by a factor of 1000. This can easily destroy the LNA. Many communication applications integrate transmitter and receiver, for example RADAR or satellite communication. In these cases, a protection circuit is required, that blocks high-power signals at the expense of attenuating the signal, and thereby lowering the signal-to-noise ratio of the whole system. Furthermore, the protection circuit usually can't be integrated with the LNA, and the system gets bulky, more expensive in fabrication, and reliability might be reduced. It was shown in the literature recently, that GaH-HEMT technology allows to boost the maximum input powers to be increased from the typical 100 mW for GaAs-HEMT technologies to about 10 W. But it has to be stated, that this success is based on a rather simple circuit topology, and that no detailled theoretical analysis of the limiting factors regarding robustness was published so far. The improvements in ruggedness of GaN LNAs therefore mainly reflect the improvements in device technology. This marks the starting point of this investigation. A new circuit topology based on stacked GaN-HEMTs promises to improve maximum safe input powers, due to the higher effective breakdown voltage at the LNA input. But it has yet to be shown that also low noise performance is possible in this concept. This new approach, but also the traditional LNA circuit topology will be theoretically investigated in order to explore and explain the limiting factors for maximum robustness. Based on measurement, the degradation mechanisms in GaN HEMTs will be investigated in order to understand the limits of critical stress below the level of immediate destruction of the device. It is the goal of this investigation to present an analytical model to optimize the ruggedness of GaN LNAs on the basis of well understood critical stress condidtions for the transistors, and also to push the maximum safe input power significantly towards higher power levels though optimized circuit topologies.

无线电接收机的第一个组件是天线，通常是低噪声放大器（LNA）。需要将通常非常弱的信号放大到足够高的功率电平，以忽略后续电子级的任何附加噪声。因此，LNA是非常敏感的低功耗组件。然而，无线电接收器通常也接收到更多的信号，而不仅仅是预期的信号。如果附近有一个大功率的发射机，其功率电平很容易超过平均接收机功率电平1000倍。这很容易破坏LNA。许多通信应用集成了发射机和接收机，例如雷达或卫星通信。在这些情况下，需要保护电路，该保护电路以衰减信号为代价来阻挡高功率信号，从而降低整个系统的信噪比。此外，保护电路通常不能与LNA集成，并且系统变得庞大，制造成本更高，并且可靠性可能降低。最近的文献表明，GaH-HEMT技术允许将最大输入功率从GaAs-HEMT技术的典型100 mW提高到约10 W。但必须指出的是，这一成功是基于一个相当简单的电路拓扑结构，并没有详细的理论分析的限制因素，有关鲁棒性发表至今。因此，GaN LNA的耐用性的改善主要反映了器件技术的改进。这是本次调查的起点。一种新的电路拓扑结构的基础上堆叠的GaN-HEMT有望提高最大安全输入功率，由于在LNA输入端的更高的有效击穿电压。但是，还没有证明在这种概念中也可以实现低噪声性能。这种新的方法，而且传统的LNA电路拓扑结构将在理论上进行研究，以探索和解释最大鲁棒性的限制因素。基于测量，GaN HEMT的退化机制将被研究，以了解低于器件立即破坏水平的临界应力的限制。本研究的目标是提出一个分析模型，以优化GaN LNA的坚固性，基于对晶体管临界应力条件的充分理解，并通过优化的电路拓扑结构将最大安全输入功率显著推向更高的功率电平。