数字移相器移频性能的分析

讨论了采用数字移相器实现移频的原理,并分别在理想情况下和有相位误差情况下对数字移相器移频的主要性能指标--杂散抑制比和载波抑制比进行了分析.     

波导二极管移相器的设计

介绍了波导二极管移相器的设计原理和实现方法。运用矩形波导的传输理论,将加载线型移相单元插入矩形波导内,对波导内的24个加载线型移相单元进行调配组合实现五位地址数码控制移相器。实测结果表明该移相器移相范围大、插入损耗低、输入驻波小、转换时间快、移相精度高及耐高功率性好。     

应用于DBS移动接收中的5位数字移相器——低成本、Ku波段

提出了一种应用于DBS移动接收中的5位数字移相器的设计方案,并通过实验验证了其实际性能。该移相器采用加载线型和反射型移相原理,首先应用ADS软件进行设计仿真;仿真结果显示该移相器具有频带内高移相精度、低插入损耗和低VSWR等性能,符合设计要求。最后使用Agilent矢量网络分析仪对实物进行测试,进而验证了设计方案的正确性。     

60MHz八位数字移相器

叙述了数字移相器的基本原理和特点，介绍了６０ＭＨｚ八位数字移相器的电路结构、实现的技术途径以及主要性能。     

基于ADS仿真设计X波段五位数字移相器

介绍了利用ADS进行X波段五位数字移相器的设计。描述了PIN管的开关特性、X波段五位数字移相器的电气特性、原理、电路设计及仿真情况。移相器采用PIN管管芯作为开关元件,5个移相位将呈线形级联布置。均方根相位误差小于3°,插入损耗在1.7~2.9 dB之间,回波损耗小于15 dB。仿真结果,满足要求。     

60MHz八位数字移相器

叙述了数字移相器的基本原理和特点，介绍了６０ＭＨｚ八位数字移相器的电路结构，实现的技术途径以及主要性能。     

一个DC-32GHz两位微机械移相器

采用分布式微机械传输线结构实现了两位移相器,并且为了减小传输线负载电容和驱动电压首次提出了用共面波导传输线来驱动微机械桥的结构(共面波导驱动结构).结果显示驱动电压小于20V,20GHz时两位移相器的相移为0°/20.1°/41.9°/68.2°,插入损耗为-1.2dB.在DC到32GHz的范围内相移具有良好的线性,插入损耗小于-1.8dB,反射损耗好于-11dB.实验结果表明了该结构在高介电常数衬底上制造低插损、宽带数字微机械射频移相器的潜力.     

数字移相器的ADS设计与仿真

介绍了四位数字移相器的原理、电路设计过程及优化仿真方法。利用射频仿真软件ADS(Advanced Design System)构建了PIN二极管的正反偏模型,讨论了运用ADS的灵敏度分析模块辅助优化移相器关键参数的方法,并基于该方法设计出了一种X波段四位数字移相器,其工作频率为9.5~10.5 GHz,相位误差<2°,各级联位输入回波损耗<15 dB,插入损耗<2.5 dB。     

量化相移对阵列天线的分析

研究了数字移相器提供的量化相移对正六边形相控阵天线扫描方向图的影响。使用一定精度移相器可降低馈源阵列的量化误差,而天线的方向图和增益只有微小的变化。分别选择2位、4位和6位移相器,比较采用连续相移和不同精度的量化相移时,天线辐射方向图的变化。通过对比分析可选择合适的数字移相器。     

一个DC-32GHz两位微机械移相器

采用分布式微机械传输线结构实现了两位移相器,并且为了减小传输线负载电容和驱动电压首次提出了用共面波导传输线来驱动微机械桥的结构(共面波导驱动结构).结果显示驱动电压小于20V,20GHz时两位移相器的相移为0°/20.1°/41.9°/68.2°,插入损耗为-1.2dB.在DC到32GHz的范围内相移具有良好的线性,插入损耗小于-1.8dB,反射损耗好于-11dB.实验结果表明了该结构在高介电常数衬底上制造低插损、宽带数字微机械射频移相器的潜力     

Genetic Algorithms for Design of Discrete Phase-only Reconfigurable Array Antennas with Fixed Dynamic Range Ratio

In this paper, we present a new method based on real-coded Genetic Algorithm (GA) with elitist model for optimal design of a reconfigurable symmetrical dual-beam uniformly spaced linear isotropic antenna array with phase-only control of quantized phase shifters. The problem is to find a common amplitude distribution that will generate a pencil beam with zero phases and a flat-top beam with discrete phases of a six-bit discrete phase shifter, without or with pre-fixing the value of dynamic range ratio (|I _max/I _min|) of excitation current amplitude distribution equal to or less than five.     

A Dual-Mode Latching Reciprocal Ferrite Phase Shifter

A ferrite phase shifter has been developed to provide latching reciprocal phase shift over a moderate frequency band. The principle of operation is based on the use of dual-mode circularly polarized waves in the active ferrite with nonreciprocal polarizers to select modes that provide reciprocal transmission phase. The physical structure of the phase shifter consists of a metallized assembly of ferrite and ceramic dielectric. A ferrite yoke is fitted over a portion of this assembly to permit latching operation. The completed phase shifter has a very simple geometry that can be produced at low cost and has relatively low insertion loss. The maximum cross-sectional dimensions are small and are consequently compatible with application in two-dimensional electronically scanned arrays. Experimental results are presented for an X-band design having a 10-percent bandwidth centered near 9 GHz.     

Electromechanical coupling modelling of distributed MEMS phase shifter for phased array antennas

MEMS phase shifter has many advantages as the ‘steering wheel’ of phased array antenna beam steering. The deformation of mechanical structures of MEMS phase shifter influenced by the complex environmental factors, which became the biggest obstacle to further enhance the performance of phased array antennas. The electromechanical coupling model between the bridge height and phase shift of the distributed MEMS phase shifter is developed. The coupling model could be used to predict the phase error and determine the bridge height tolerance for the deformed MEMS phase shifter. The simulation results of four-bit distributed MEMS phase shifter with 15 bridges illustrate the validity of coupling model and demonstrate the application potential for engineering design and test.     

基于铁电移相器的Ka波段低成本相控阵天线研究

为解决铁电体陶瓷移相器中高相对介电常数材料间的匹配问题,研制了一种可用于Ka波段低成本相控阵天线的新型铁电体陶瓷材料移相器,并用其设计制作了一种一维电扫低成本相控阵天线。结果表明:通过利用三级阻抗匹配技术,所制新型移相器中高相对介电常数材料间的匹配问题得到了有效解决。当外加偏置电压约为11 kV时,该移相器可在损耗小于2.2 dB的情况下实现360°相移。     

毫米波数控移相器的设计与制作

移相器是毫米波相控阵雷达收发系统重要电路,基于安捷伦IC-CAP软件及砷化镓原片工艺线,研究了砷化镓毫米波开关器件测试、建模技术及其应用。采用0.15μm GaAs PHEMT工艺成功制作了一款Ka波段5位数控移相器MMIC,对毫米波数控移相器MMIC集成电路的设计、制作过程进行了阐述,并给出了测试结果。电路设计采用了开关滤波拓扑结构,运用微波探针在片测试系统对芯片进行了实测,在34~36 GHz范围内获得了优异的电性能。给出了移相器的测试曲线,32态均方根移相误差(RMS)5°,插入损耗典型值8 dB,输入/输出电压驻波比系数典型值2,芯片尺寸为2.5 mm×1.5 mm×0.1 mm。     

双模互易锁式铁氧体移相器

最新研制出的双模互易锁式移相器具有体积小、结构简单、成本低廉、性能优良等特点。本文介绍了这种移相器的原理、设计方案及应用前景，并提供了在X波段的实际性能。     

A novel tunable transmission line and its application to a phase shifter

This letter describes the design of a novel transmission line, where characteristic impedance can be adjusted electronically, and its application to a phase shifter. A tunable transmission line enables microwave circuit designers to have flexibility and better return loss which can enhance its tuning range. A UHF band distributed analog phase shifter, as well as a tunable transmission line, is presented. The characteristic impedance of a fabricated novel transmission line varies from 10 to 69.5/spl Omega/, which demonstrates its tunability, and the fabricated UHF phase shifter using this novel line shows the possibility of better reflection coefficient and wider tuning range over the conventional capacitively-loaded distributed phase shifter.     

数控单片移相器的CAD

数控单片移相器的设计技术具有较大的特殊性与复杂性,必须依靠计算机辅助设计提高设计的准确性.对数控单片移相器的计算机辅助设计问题进行了论述,着重讨论了电路设计效率的提高及电磁场验证等问题,为数控单片移相器的研制提供了实用的解决方案.应用这一研究成果,成功开发出高性能X波段单片五位数字移相器.     

模拟式360°线性移相器原理与应用

介绍了模拟式360°线性移相器的基本原理及优化设计方法,分析和讨论了主要技术指标的物理意义和技术规范.利用优化设计方法设计的360°线性移相器线性度优于±1.77%,工作带宽500 MHz,并在同步移相扫描应用中获得了满意的效果.