Analysis and Compensation of Phase Variations Versus Gain in Amplifiers Verified by SiGe HBT Cascode RFIC
Analysis and Compensation of Phase Variations Versus Gain in Amplifiers Verified by SiGe HBT Cascode RFIC
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DOI：
10.1109/tmtt.2009.2025415
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发表时间：
2009-07
影响因子：
4.3
通讯作者：
F. Ellinger;U. Jorges;U. Mayer;R. Eickhoff
中科院分区：
文献类型：
--
作者：
F. Ellinger;U. Jorges;U. Mayer;R. Eickhoff
分析了共发射极和共基极放大器的传输相位随增益的变化，揭示了这些阶段可以调谐以产生相反的相位特性与增益。通过级联这两个阶段，例如，在级联代码的基础上，并优化添加的反馈元素，有可能补偿这些相位变化。推导了基于双极晶体管的通用分析方法。然而，这些见解可以映射到其他晶体管，如场效应晶体管。通过在0.25 μ m硅锗异质结双极晶体管中实现低噪声级联放大器，验证了上述分析。在50 ω端，在5.2至5.9 GHz的频率范围内测量到1.6 v电源电压、1 ma电流消耗、7 dB + 0.25 dB增益、小于3.2 dB的噪声系数和-3 dBm的三阶输出截距。对于12 dB和20 dB的增益控制范围，传输相位变化分别减少到3度和6度，这比传统的非补偿级联码拓扑要好7倍左右。该全集成电路非常适合应用自适应天线组合并按照802.11 a/n标准运行的无线局域网系统。
The transmission phase variations versus gain in common emitter and common base amplifiers are analyzed revealing that these stages can be tuned to yield opposite phase characteristics versus gain. By cascading these two stages, e.g., on the basis of a cascode, and optimizing added feedback elements, it is possible to compensate these phase variations. A universal analysis based on bipolar transistors is derived. However, the insights can be mapped to other transistors such as field-effect transistors. The analysis is verified by implementation of a low-noise cascode amplifier in 0.25-mum silicon germanium heterojunction bipolar transistors. At 50-Omega terminations, 1.6-V supply voltage, 1-mA current consumption, and a gain of 7 dB plusmn 0.25 dB, a noise figure of less than 3.2 dB, and a third-order output intercept point of -3 dBm are measured within a frequency range from 5.2 to 5.9 GHz. For a gain control range of 12 and 20 dB, the transmission phase variations are reduced to 3deg and 6deg, respectively, which is around a factor of 7 better than for a conventional noncompensated cascode topology. The fully integrated circuit is well suited for wireless local area network systems applying adaptive antenna combining and operating in accordance to the 802.11 a/n standards.