【作者】 姜海莺；

【导师】 高攸纲；

【作者基本信息】 北京邮电大学 ， 电磁场与微波技术， 2015， 博士

【摘要】 本文第一次全面、系统、深入和创新性地对智能移动手机设计中的EMC(电磁兼容)问题进行了研究,该研究能为智能手机中电磁兼容问题的设计、分析和解决提供全面而深入的参考。首先本文对智能手机的物理结构、硬件框图、运行原理、存在或潜在的噪声和干扰源特性以及从源头抑制干扰的办法进行了介绍。本文第一次建立了智能手机的电磁拓扑图,并基于建立的电磁拓扑图对智能手机设计中存在和潜在的电磁兼容问题进行了初步的分类、分析和归纳。接着本文对智能手机中特有的电磁兼容问题(CSE (Continuous Spurious Emission)问题,RSE (Radiated Spurious Emission)问题和desense (Sensitivity Degradation)问题)进行了进一步的分析,绘制出了用于对这些问题进行分析和实验的流图。然后本文找到和明确了要实现智能手机电磁兼容而需要进行全面、详细和深入研究的方向：它们分别是提高接收机抗扰能力的研究,减少发射机干扰生成的研究,共存问题的研究,智能手机电路中干扰传导耦合的研究,传输线模型及其在智能手机EMC分析中应用的研究,智能手机中非有意辐射的研究以及屏蔽罩导致问题的研究,共七大方向。最后本文用七章分别对这7大研究方向展开了系统而深入的研究。对于每个研究方向,作者首先对前人已完成的工作进行学习和总结,找到不足或是前人还没有完成的工作；然后围绕这些不足或是未完成的工作展开了研究；最后又将研究的结果用到智能手机的电磁兼容设计工作中,并对具体的电磁兼容问题的抑制和设计以及分析和解决提供全面和深入的指导。本论文主要的创新点有以下几个方面：(?) 建立了智能手机的电磁拓扑图。(?) 通过理论计算、仿真和实验验证的方法完成了智能手机接收机的基带处理方式如调制方式,扩频方式和信道编码方式以及接收机射频链路对接收机抗干扰能力影响的分析,完成了实际无线接收机射频前端的优化设计(?) 验证了用X参数模型来预测放大器对信号质量的畸变和及放大器的频谱再生的可行性和准确性。(?) 找到共存问题的本质,完成了LTE Inter-band载波聚合(FDD LTEB1/B3)中共存问题的分析以及完成了具体SGLTE (Simultaneous GSM and TDD-LTE)手机共存问题的分析、设计和验证。>利用分布参数和电压电流定理加上静电磁场比拟建立了双导体或多导体系统对外界电磁场激励的响应的传输线方程；找到了能将智能手机中非等长PCB双走线间的相互耦合问题等效成等长传输线间相互耦合的问题的等效长度法,并找到了该法的具体实现步骤；用传输线模型和积分方法完成了智能手机中不等长PCB(Printed Circuit Board)走线间弱耦合而导致被干扰走线沿线干扰电压和电流通用公式的推导；完成了在特定的端口阻抗情况下被干扰走线弱耦合而导致的端口电压和电流以及功率的推导,以及耦合功率决定因素的分析。>建立了智能手机中实际电流回路的,且能对实际回路中共模电流生成机理、实际回路的辐射机理以及实际回路对外界干扰接收机理进行清晰解释的等效电路模型。>利用实验的方法对一具体智能手机设计过程中屏蔽罩导致CSE问题的分析和解决,以及应用仿真的方法得到了抑制屏蔽罩对微带线影响的设计指导。更多还原

【Abstract】 The EMC problems during the smart mobile phone design and research stage are comprehensively, systematically, deeply and creatively studied in this dissertation by the first time, and the studying results must be as good reference to analyzing, resolving and suppressing the EMC problems in smart mobile phone. Firstly, the mechanical structure, hardware block diagram and operation theory of the smart phone, and the noise or interference source existing or potentially existing in smart mobile phone is introduced. Then, the electromagnetic topology of smart mobile phone is established, and based on the topology all the EMC problems are preliminarily categorized, analyzed and concluded. Moreover, the EMC problems such as CSE(Continuous Spurious Emission), RSE(Radiated Spurious Emission) and Desense(Sensitivity Degradation) those are unique to smart mobile phone are further analyzed, and their flow charts for experiment analysis and root causes fixing are figured out, and the EMC problems requiring further study are found, which are totally 7 kinds:They are the study on improving the receiver’s ability to suppress the interference, the study on suppressing the interference from the transmitter, the study on co-existence problems, the study on the conducted coupling of interference in smart mobile phone circuits, the study on transmission line model and on its use for analyzing and resolving the EMC problem in smart mobile phone, the study on the unintentional radiation mechanism and control and the study on the problems induced by shielding can. Finally, all of the 7 kinds of the research directions are studied respectively in 7 chapters:firstly, the progress of each research direction is concluded, and the new researching points such as the work or study which requires complementary work or which remains unfinished are found out; secondly, the study work and efforts on the new points are performed, and the novel results are gotten; at last, the instructions or guidelines for the EMC design work are concluded, and are used to design, analyze and resolve the real EMC problems.The main novel points in this dissertation are as follows.The elecromagnetic topology of the smart mobile phone is established.The influnce of baseband signal processing such channel coding, modulation and spreading, and the influnce of the RF link circuits to the wireless receiver’s ability to suppress the interference in smart mobile phone is analyzed and studied by mehods of theory analysis, simulation and experiment.The verificaiton of the feasibility and precision of X paramter’s pridiction to th smart mobile phone’s high power amplifier’s distortion to the signal quality and its out band spurious generation is performed and finished.The essence and mechanism of the co-existence problem is concluded. The co-existence problems in the Inter-band LTE (FDD LTE B1 and B3) in mobile phone are anlyzed. The analysis and degin of co-existence problems for a real designing SGLTE(Simultaneous GSM and TDD-LTE) mobile phone is finished, and then the design is verifed by performing test on engineering samples.The transmission line equation is derived for the two-condcutor or multi-conductor systems’reaction to the stimulation of the radiation interference along the conductors by the methods of electrostatic analogy and by using the KVL and KCL(circuits thoery) alogn the conductors. The method to equate the coupling between two PCB traces with unequal length with the coupling between two transmission lines with equal length is abtained, and the steps of this method are specified. The general analytical expression of the voltage and current along the vitim PCB(Printed Circuit Board) trace due to the weakly coupling from the interference PCB trace, which parallels the victim trace and is shorter than victim trace, is abtained; moreover, the analytical expression of ports’voltage, current and power of the victim trace with special port’s impedacne is abtained, the factors that decide the ports’coupling power are listed and further analyzed, and the methods and guidlines for PCB traces design are worked out.The equivalent circuit model, which can be as good equivalence to real current loop circuits, and can clearly figure out the mechanisms of the common mode current generating, of unintenatianal radiating from the real current loop and the inteference receiving by the real current loop, is found out.The CSE problem induced by the shielding can in a real moble phone design is experimentally analyzed, and the feasible solution is recommended. By method of simulation, the design reference and guidelines for suppressing the shielding cans’ influence to microstrip line are proposed.更多还原