L波段卫星导航接收机关键模块研究

发布时间：2018-06-22 12:16

本文选题：GPS + 低噪放　；参考：《西安电子科技大学》2014年硕士论文

【摘要】：随着航空、航天、通信以及计算机技术的迅速发展,卫星导航系统的运用也随之得到了较大的发展,卫星导航全球化、大众化以及民用化的程度也得到了较大的拓展。人们对于卫星导航的性能要求也在逐步的提高,高定位精度和一些特殊功能已成为现在卫星导航研究的热点。本文对L1波段卫星导航接收机中两个关键模块低噪放和混频器进行了分析和讨论,研究了低噪放和混频器的改进方法,对低噪放和混频器的传统结构进行了一定的改进以提高其性能。本文研究分析了基于CMOS工艺的低噪放的设计,针对传统结构无法兼顾最小噪声和最大功率传输的问题,给出了改进型低噪放的设计和分析方法,提高了电路的噪声性能和增益。使用该改进结构可以实现较为良好的最小噪声匹配和最大功率传输匹配。本文研究分析了传统双平衡Gilbert混频器的性能指标和结构,详细的分析和计算了其增益、噪声和线性度,给出了改进性能的方法。针对传统结构电压余度不足和单端输入的问题,分别采用旁路电流注入和伪差分结构的方式,改善了其噪声性能、变频增益和线性度,提高了电路的集成度。本文在低噪声放大器的设计中,完成了基于TSMC 0.18μm CMOS工艺低噪声放大器的仿真设计。仿真结果表明,改进型低噪放在1.575GHz点处的NF为1.063dB,S21为15.92dB,S11和S22均小于-15dB,即输入输出匹配网络实现了较好的功率匹配,P1dB为-15.7dBm,功耗为5.31mW,实现了较好的性能。在混频器的设计中,完成了基于TSMC 0.18μm CMOS工艺改进型双平衡Gilbert混频器的仿真设计。仿真结果表明,在中频4MHz处其NF为15.31d B,变频增益为13.15dB,P1dB为-15.4dBm,功耗为6.48mW,实现了较好的性能。本文所设计的低噪放的噪声性能还有待提高,进一步降低低噪放的噪声是提高接收机系统噪声性能的关键因素,也是低噪放进一步研究的方向,可采用噪声抵消技术来消减低噪放的噪声,从而提高其噪声性能。为提高卫星导航射频芯片的多系统兼容性,多模射频前端架构是其关键的一步,而多频点兼容的低噪放的设计是其关键点,因此对于多频点兼容的低噪声放大器是下一步研究的方向。
[Abstract]:With the rapid development of aviation, aerospace, communications and computer technology, the application of satellite navigation system has also been greatly developed. The degree of globalization, popularization and civilian use of satellite navigation has also been greatly expanded. The performance requirements of satellite navigation have been gradually improved, and high positioning accuracy and some special functions have become the focus of satellite navigation research. In this paper, two key modules of L1 band satellite navigation receiver, low noise amplifier and mixer, are analyzed and discussed, and the improvement methods of low noise amplifier and mixer are studied. The traditional structure of low noise amplifier and mixer is improved to improve its performance. In this paper, the design of low noise amplifier based on CMOS process is studied. The design and analysis method of improved low noise amplifier is presented to improve the noise performance and gain of the circuit, aiming at the problem that the traditional structure can not take into account the minimum noise and the maximum power transmission. The improved structure can achieve better minimum noise matching and maximum power transmission matching. In this paper, the performance index and structure of the traditional double-balanced Gilbert mixer are studied and analyzed. The gain, noise and linearity of the dual-balanced Gilbert mixer are analyzed and calculated in detail, and the methods to improve the performance are given. In order to solve the problems of voltage redundancy and single-terminal input in traditional structure, the noise performance, frequency conversion gain and linearity of the circuit are improved by using bypass current injection and pseudo-differential structure, respectively, and the integration of the circuit is improved. In the design of low noise amplifier, the simulation design of low noise amplifier based on TSMC 0.18 渭 m CMOS process is completed. The simulation results show that the improved low noise NF at 1.575GHz is 1.063dBN S21, 15.92dBN S11 and S22 are less than -15dB, that is, the input and output matching networks achieve better power matching P1dB -15.7dBmand power consumption 5.31mW. In the design of mixer, the simulation design of double-balanced Gilbert mixer based on TSMC 0.18 渭 m CMOS process is completed. The simulation results show that the NF is 15.31 dB, the frequency conversion gain is 13.15 dB and the power consumption is 6.48 MW at the intermediate frequency of 4MHz. The noise performance of the low noise amplifier designed in this paper needs to be improved. Further reducing the noise of the low noise amplifier is the key factor to improve the noise performance of the receiver system, and it is also the direction of further research on the low noise amplifier. Noise cancellation technology can be used to reduce the noise of low noise amplifier and improve its noise performance. In order to improve the multi-system compatibility of satellite navigation RF chip, the multi-mode RF front-end architecture is a key step, and the design of multi-frequency point compatible low-noise amplifier is the key point. Therefore, low noise amplifier (LNA) compatible with multi-frequency is the next research direction.
【学位授予单位】：西安电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN965.5

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