节点文献
Ka波段I/Q调制器的研究
Study of Ka-band I/Q Modulator
【作者】 侯学智；
【导师】 吕红亮；
【作者基本信息】 西安电子科技大学 ， 微电子学与固体电子学， 2011， 硕士
【摘要】 异质结双极晶体管(HBT)是毫米波、微波应用领域中最重要的器件之一,其中砷化镓(GaAs) HBT具有更好的高频特性、绝缘性能以及更高的电流增益。本文主要对基于GaAs HBT器件Ka波段的I/Q调制器进行了研究。首先对Ka频段基于吉尔伯特单元混频器结构的I/Q调制器完成了简单的设计以及仿真,其中本振抑制度为27.7dB左右,边带抑制度为26.6dB左右。本文的主要工作,完成了Ka频段基于GaAs HBT器件的模拟反射型I/Q矢量调制电路的设计以及仿真。其中包括对冷模HBT器件在不同偏置条件下器件特性的变化、Ka频段的Lange耦合器、Ka频段的威尔金森功率分配器以及对I/Q调制中的BPSK调制器和QPSK调制器都进行了详细的设计和分析。本矢量调制器的载波抑制大约为25.6dB,边带抑制大约为27dB。本文最后在I/Q矢量调制电路基础上进一步提出了一种新的电路结构,通过对原有电路结构的改进在不影响电路功能的前提下节省了大量的芯片面积,从而节省了制作成本。
【Abstract】 Heterojunction bipolar transistor (HBT) is one of the most important devices in millimeter wave and microwave applications, and GaAs HBT has better high frequency characteristics, insulation performance and higher current gain. In this paper, I/Q modulators were proposed based on Ka-band GaAs HBT device.Firstly, a I/Q modulator based on Ka-band mixer Gilbert cell structure is completed in which the degree of carrier suppression is about 27.7dB, and degree of sideband suppression is about 26.6dB.Secondly, reflection-type binary phase-shift keying and in-phase and quadrature modulator are reported which is the main work in this paper. A cold-mode HBT device model with varying bias conditions is proposed, which is suitable for millimeter-wave circuit design and simulation. The analysis and design for the reflection-type modulators are also presented which including the design of Ka-band Lange coupler and Ka-band Wilkinson power divider .The vector modulator carrier suppression of about 25.6dB, sideband suppression is about 27dB.Finally, the basis of the I/Q vector modulation circuit further proposed a new circuit structure, through the improvement of the original circuit does not affect the circuit functions in the premise of saving a lot of chip area, thus saving production costs.