【作者】 杨自强；

【导师】 林为干；

【作者基本信息】 电子科技大学 ， 电磁场与微波技术， 2008， 博士

【摘要】 微波/毫米波单片集成电路(MMIC)具有体积小、重量轻、可靠性高、稳定性好等优点,不仅在卫星通信、相控阵雷达系统、电子战等军事应用领域具有非常广泛的应用,而且在民用方面也有相当大的市场。PHEMT(赝匹配型高电子迁移率管)器件具有优异的高频特性、功率特性和低噪声特性,使之成为微波/毫米波单片集成电路领域中最有竞争力的有源器件之一。本文设计了若干Ka频段接收机部件单元单片集成电路,通过商用的0.2μm GaAs PHEMT工艺实现流片。主要研究内容摘要如下:(1)设计完成了Ka频段两级低噪声放大器芯片,工作频率为29-33GHz,实现增益大于10dB,噪声系数小于3.5dB。(2)设计完成了Ka频段宽带低噪声放大器芯片,该芯片为四级放大结构,采用自给偏压设计,实现单电源1.8V供电,功耗仅为81mW,在整个Ka频段内增益大于18dB,噪声系数小于3.8dB。(3)设计完成了Ka频段宽带镜频抑制混频器芯片,采用Lange Coupler等宽带电路实现混频器的宽带特性,在30-38GHz频率范围内,变频损耗小于12.6dB,镜频抑制度大于20.4dB。(4)设计完成了Ka频段宽带四次谐波镜频抑制混频器芯片,采用Marchand Balun和阻性PHEMT器件构建偶次谐波混频单元,应用Lange Coupler等宽带电路实现混频器的宽带特性,首次实现了Ka频段四次谐波镜频抑制混频器芯片。同时该芯片采用了小型化设计技术,使芯片面积大大缩小,该芯片与国外二次谐波镜频抑制混频器芯片相比面积相当,甚至更小。该小型化技术也可应用于其它毫米波单片集成电路的设计中。(5)设计完成了超宽带有源二倍频器芯片。该芯片由平衡式倍频器和放大器两部分组成。平衡式倍频器由有源Balun和两个FET倍频单元构成,实现了对奇次谐波的有效抑制。放大器由分布式放大器和两级共源放大器组成,实现宽带放大。该倍频器芯片输入频率为1.5-25GHz,工作带宽超过了4个倍频程,在输入频率为1.5-20GHz时,倍频增益大于0dB。该倍频器芯片可实现将微波信号倍频到Ka频段。(6)微波/毫米波单片集成电路中的无源元件建模技术研究:将神经网络方法和电磁仿真相结合对Lange Coupler进行建模,所得模型具有和电磁仿真结果同样的准确度,但所需的计算时间却非常少,该模型可用于Lange Coupler电路的设计和优化。引入支持向量机回归方法对MIM(metal-insulator-metal)电容进行建模,该模型适合于大规模CAD优化过程中的在线使用,同时充分证明支持向量机回归方法在微波/毫米波无源电路建模方面的有效性。以上研究的两种建模方法也适用于其它微波/毫米波单片集成电路中无源元件建模。更多还原

【Abstract】 Due to the advantages of small size, light weight, high reliability and stability, microwave and millimeter-wave monolithic integrated circuits (MMICs) are widely used in military fields, such as satellite communication, phased-array radar system and electronic warfare system. Also there is a large market for the MMIC using in the civil fields. The PHEMT (pseudomorphic high electron mobility transistor) device has outstanding high-frequency characteristics, power characteristics and low-noise characteristics, and it is one of the most competitions in the field of microwave and millimeter-wave monolithic integrated circuits. This paper designs some Ka-band receiver components monolithic integrated circuits, which are fabricated by a commercial 0.2μm GaAs PHEMT process. Major contents of the paper are abstracted as following:(1) A Ka-band two stage low noise amplifier (LNA) MMIC is designed. The LNA achieves a gain of more than 10 dB and a noise figure of less than 3.5 dB in the frequency range of 29-33 GHz.(2) A Ka-band four stage broadband LNA MMIC is designed. For the application of self-bias technique, the LNA is biased from a single power supply. The power consumption of the LNA is only 81 mW. The LNA achieves a gain of more than 18 dB and a noise figure of less than 3.8 dB in the whole Ka-band.(3) A Ka-band broadband image rejection mixer MMIC, which uses a Lange Coupler to realize the broadband characteristic of the mixer, is designed. The mixer achieves a conversion loss of less than 12.6 dB and an image rejection ratio of more than 20.4 dB in the frequency range of 30-38 GHz.(4) A Ka-band broadband fourth-harmonic image rejection mixer MMIC is designed. The unit mixer uses a 0°/180°Marchand Baluns and two resistive FET mixers to realize even harmonic mixing. The Lange Coupler is used at RF port to realize the broadband characteristic. The mixer is the first fourth-harmonic image rejection mixer to the author’s knowledge. The chip size of the mixer is greatly reduced by using the miniaturization technique, which is equal to or even smaller than that of the reported Ka-band monolithic sub-harmonic image rejection mixer. The miniaturization technique also can be used to other millimeter-wave monolithic integrated circuits.(5) An ultra-wideband active doubler MMIC is designed. The chip consists of two parts: balanced doubler and amplifier. The balanced doubler, which can reject odd harmonic, consists of active balun and two unit FET doublers. The amplifier, which can operate over a broadband frequency range, consists of distributed amplifier and two stage common souce amplifier. The doubler MMIC operates with input frequency of 1.5 to 25 GHz, which is more than four octave frequency ranges, and achieves a conversion gain of more than 0 dB with input frequency of 1.5 to 20 GHz. The doubler MMIC can multiply the microwave signal to Ka-band signal.(6) The modeling method for passive elements in microwave and millimeter-wave monolithic integrated circuits has been studied. Electromagnetically trained artificial neural network (EM-ANN) model for microstrip Lange Coupler is presented. The model can provide the same accuracy as the Full-wave EM simulation, but the computing time is extremely short compare to the EM simulation method. The model can be used to design and optimize the Lange Coupler circuit. The Support Vector Machine (SVM) regression method has been introduced into modeling of the MIM (metal-insulator-metal) capacitor. The model presented in this paper is useful for interactive CAD application, which proves the validity of the SVM regression method in microwave and millimeter-wave passive elements modeling. The two modeling methods introduced above also can be used for modeling the other passive elements in microwave and millimeter-wave monolithic integrated circuits.更多还原