【作者】 张凯；

【导师】 郭志勇；

【作者基本信息】 电子科技大学 ， 信息与通信工程， 2017， 硕士

【摘要】 毫米波频段为26.5GHz~300GHz,具有波长短的特点,因此毫米波系统更容易小型化。毫米波技术是解决频谱资源紧缺的一项关键技术,因此毫米波技术在通信、雷达等领域有重大的价值,尤其是在汽车防撞领域。尽管毫米波线性调频连续波(Frequency Modulation Continuous Wave,FMCW)雷达具有广阔的市场价值与前景,但是目前国内毫米波雷达事业发展面临着诸多问题,如产品成本高、难以推广、技术封锁等。本课题研究的毫米波线性调频连续波体制雷达工作频段为75.9GHz-76.5GHz,具有测量精度高、发射功率低、发射波形简单等优点,除了可以应用于汽车防撞领域外,也可用于安防、无人机探测等领域。本文依托E波段FMCW测角雷达项目,通过比较不同方案的优劣势,结合各种频率源方案的特点,设计出覆盖12.65GHz-12.75GHz的Ku波段线性调频连续波频率源。频率源的结构为锁相环(Phase Locked Loop,PLL)环内混频加DDS环外混频加DDS二次混频。为了提高频谱的纯净度,最后设计了一款新型的半模基片集成波导(Half-Mode Substrate Integrated Waveguide,HMSIW)和缺陷地结构(Defected Ground Structure,DGS)组合的无源滤波器。此滤波器具有很强的选择性,适用于射频前端倍频前的滤波。本文的主要内容如下:(1)总结国内外线性调频连续波毫米波雷达及频率源研究的现状,简要介绍FMCW体制雷达角度、速度、距离测量的基本原理。(2)讨论现代频率合成的技术,主要介绍PLL和DDS模块。对比各种频率源方案的优缺点,并根据项目要求确定最优方案,并分析方案的可行性和预期性能。(3)设计并加工了一款新型结构的无源窄带带通滤波器,该滤波器使用DGS和HMSIW横向组合的方式,滤波器选择性好,经过测试后符合设计要求。(4)根据选定的方案设计频率源,包括电路设计、器件选择、程序编写和调试工作,并给出频率源的测试结果,测试结果符合项目要求。参与组织雷达系统联调,给出测试结果并予以分析。更多还原

【Abstract】 Millimeter wave band is 26.5GHz-300 GHz.The millimeter-wave system is easier to miniaturize because the wavelength is short.Millimeter wave technology is the key technology to solve the shortage of spectrum resources and has great significance in the field of communications and radar,especially in the field of automotive crash radar.Although Millimeter wave linear frequency modulation continuous wave(FMCW)radar has a broad market and social significance,it is facing many challenges such as high product cost,hard to popularize,technical blockade.The working frequency of the FMCW radar in this thesis is 75.9GHz-76.5GHz.It has advantages of high measurement precision,low transmission power,low product cost and simple transmission waveform and can be used in automotive anti-collision,security detection,UAV detection and other fields by using different detection algorithms.In this thesis,relied on FMCW angle measuring radar project,the Ku-band FMCW frequency source covering 12.65GHz-12.75 GHz is designed by comparing the advantages and disadvantages of different schemes.The structure of the frequency source is the mixing of the PLL in the phase-locked loop(PLL)and the mixing of the DDS outside the ring.The output signal of the frequency source is multiplied by six times and then as output signal of the radar system.In order to improve the purity of the spectrum,a novel filter is proposed.This filter using half mode substrate integrated waveguide(HMSIW)and defected ground structure(DGS)is highly selective.The main contents of this thesis are as follows:(1)The present situation of FMCW radar and frequency source at home and abroad are Summarized.The basic principle of FMCW radar is introduced.(2)Main technology of modern frequency synthesizer are introduced.Optimal scheme base on project requirments is determined by comparing the advantages and disadvantages of various frequency source schemes.Then,feasibility and performance of the proposed scheme is analyzed.(3)A DGS mixed Half-Mode SIW filter is proposed.The filter has high selectivity,low insertion loss and can be used in this design.(4)The hardware and software of the frequency source according to the scheme are designed.the test results are given and it meets the project requirements.Finally,the radar test results are given.更多还原