Measuring Group Delay of Frequency Downconverter Devices Using a Chirped RF Modulated Signal

This paper discusses the implementation possibilities for making Group Delay measurements of RF frequency converting devices using a standard RF semiconductor Automatic Test Equipment (ATE) that cannot be done using the standard S-parameter measurement due to the difference in frequency from the input to the output of the device. We discuss how using a chirp waveform modulating an RF generator can be used to sweep the frequency response of a RF frequency-converting device and how to produce such a modulation waveform in digital signal processing. We will describe how to implement a group delay test based on our previous work in the baseband domain and how to understand the errors pertaining to measuring a Radio Frequency Receiver. The measurement of the Group Delay of an RF front-end filter and post down convert IF filter will be demonstrated. We will also describe how to produce and maintain a stable frequency reference so that any down converted signal would be a true representation of the modulation signal applied to the RF Source and not corrupted by Phase Noise. We will show how to implement a group delay test based on our previous work in the baseband domain and how to understand the errors pertaining to measuring a radio frequency receiver. The measurement of the group delay of an RF mixer and pre and post down convert RF/IF filters will be demonstrated. The central goal of this paper is to demonstrate how a group delay test can be done at RF, with a frequency translating device, in a cheap and effective manner on semiconductor Automatic Test Equipment in a production environment.     

金刚石SAW滤波器的设计和制作

通信系统向高频的发展趋势使声表面波(SAW)滤波器技术面临着越来越多的挑战。利用传统材料制作SAW滤波器的中心频率很难达到GHz频段,因此探索在高声速材料基础上制作SAW滤波器成为一种必然趋势。基于高声速材料金刚石设计了IDT/ZnO/金刚石结构的薄膜SAW滤波器,设计了镜像阻抗连接IDT的结构参数,并采用ADS软件对该结构进行了建模仿真。然后,通过ZnO薄膜制备工艺和IDT电极制备工艺,获得了金刚石SAW滤波器样品。最后,采用RF探针台对所制得的样品进行了性能测试和数据分析。测试结果表明,在金刚石厚膜衬底上获得了频率超过1 GHz的SAW滤波器样品。     

2 GHz宽带低损耗SAW滤波器的研制

利用射频电路模拟软件中构建的声表面波(SAW)低损耗滤波器设计工具,对S波段SAW滤波器的设计技术展开研究。通过建立集总参数模型,分析高频下封装效应对滤波器性能的影响,并成功研制出中心频率达2.2GHz,最小插入损耗为-3dB,相对带宽达到7%的SAW滤波器,测试与仿真结果基本一致。     

一种射频体声波滤波器的版图设计与仿真

射频体声波滤波器品质因子高,尺寸小,其性能已超过声表面波滤波器,将其替代传统的射频滤波器极具性能和价格优势。本文建立了适用于体声波滤波器性能分析的巴特沃斯—范戴克（MBVD）模型,采用梯形级联方式设计了一种射频体声波滤波器的版图。在此基础上以中心频率为1.99GHz,带宽56MHz的体声波滤波器为例,对不同连接级数梯形滤波器的插入损耗、阻带抑制进行了仿真与分析讨论,在4阶滤波器中其带外衰减达到了-29.708dB。采用微机电机械系统工艺制备的2阶和3阶滤波器传输特性的测试曲线与仿真结果基本吻合,表明射频体声波滤波器具有广泛的应用前景。该模拟结果可作为射频体声波滤波器设计的一个重要参考。     

数字无绳电话用声表面波滤波器

简要介绍了四川压电与声光技术研究所研制的数字无绳电话用声表面波滤波器,包括110．592MHz中频滤波器和900MHz系列射频滤波器。中频滤波器的插入损耗为3．5dB,射频滤波器的插入损耗为2．5－3dB。     

超宽带声表面波滤波器的设计

该文精确模拟了基于弛豫铁电单晶的声表面波(SAW)梯形滤波器的性能。首先介绍了由谐振器构成的梯形SAW滤波器的工作原理,利用QUCS软件建立了七阶梯形滤波器的仿真模型。结果表明,该单晶能实现高达620 MHz的超宽带SAW滤波器(中心频率1GHz),比传统压电材料的滤波器带宽高3倍;通过优化各支路谐振器的静态电容及传统梯型滤波器的结构,牺牲了一定的带宽,但获得了较高的带外抑制和过渡带的陡峭度;讨论了不同品质因数对滤波器带内插损的影响。     

晶圆上测试射频系统级芯片的挑战(英文)

随着无线通讯产业推动芯片集成度的不断提高,系统级封装(SIP)和多芯片组件(MCM)被更多采用,射频系统级芯片(RF-SOC)器件的良品测试已成为一大挑战。这些器件与传统的单晶片集成电路相比,具有更高的封装成本,并且由于采用多个晶片,成品率较低。其结果是进行晶圆上综合测试的成本远超过最终封装后测试器件的成本。此外,一些IC制造商销售裸晶片以用于另一些制造商的SIP和MCM中,这就要求发货的产品必须是良品。以蓝牙射频调制解调芯片为例,讨论了RF-SOC器件良品晶片(KGD)的测试难点和注意事项。对此样品,除了在晶圆上进行射频功能测试的难点,还有同时发射和测量数字、射频信号的综合问题。此外对被测器件(DUT)用印制线路板布线的难点,包括晶圆探针卡的设置及装配进行探讨。还介绍了选择探针测试台、射频晶圆探针卡和自动测试设备(ATE)时需考虑的因素。并以晶圆上测试的系统校正,包括难点和测试方法,作为结尾。这颗蓝牙射频调制解调芯片的实际测试数据也会被引用,以佐证和加深文章中的讨论。     

日本近年RF MEMS开关研究的进展

RFMEMS是射频表面微机械系统简称。射频表面微机械系统现在包括滤波器和微型电器元件,如开关,微可变电容和微可变电感。射频开关按驱动原理分有静电,压电,电磁以及热驱动。由于这一研究的高频化和高精度的特点,目前开关的研究集中在静电驱动的方式的研究上,从上市的产品来看,静电驱动是最有希望的RFMEMS的执行机构。静电执行器驱动的RFMEMS开关成为下一代高频通讯中的关键部件。     

电磁寄生参数在高频SAW滤波器设计中的应用

在设计高频声表面波(SAW)滤波器的过程中,若只考虑封装壳和键合线的电磁寄生参数而忽略汇流条的电磁寄生参数,则SAW滤波器的实际性能易受汇流条寄生参数影响而出现通带波动和驻波增大等问题。该文拟用电声-电磁联合仿真方法设计高频SAW滤波器以解决汇流条寄生参数对SAW滤波器性能的影响。通过此方法研制的滤波器通带插入损耗小于1 dB,波动0.5 dB,通带内驻波最大值2.1,-1.5 dB带宽75.7 MHz,-3 dB带宽84 MHz (相对带宽为4.8%),-30 dB带宽112 MHz,BW_{-3 dB}/BW_{-30 dB}矩形系数1.33。包含封装壳、键合线及汇流条的寄生参数的理论仿真结果与实验测试结果吻合较好,表明了采用此模型设计高频SAW滤波器的可行性。     

5G通信组件技术特点及军事通信领域应用

本文介绍了目前三种 5G 射频组件,并关注这些组件在军事通信领域中的应用。通过详细介绍 RF MEMS 开关、基于物联网的能量收集器、RFSAW 滤波器三种组件的内部结构、技术特点以及它们支持增强系统应用的功能，同时根据其技术特点，对 5G 通信配套组件在未来军事通信领域的应用进行了展望。     

RF oscillator implementation using integrated CMOS surface acoustic wave resonators

This work is a proof of concept that a monolithic CMOS surface acoustic wave (SAW) resonator can function as an RF oscillator. The design of the oscillator includes the measurement characteristics of the CMOS SAW resonator, its matching networks, and RF amplifier is described. The integrated SAW resonator, with its operating frequency controlled by the spacing of its transducers was fabricated using a combination of CMOS plus post-CMOS processes. Based on the operation and performance of the SAW resonators, an equivalent circuit model of the CMOS SAW resonator was developed. A series resonant oscillator design was simulated using Microwave Office^TM. The designed matching network improves both the insertion losses and the phase slope of the resonator, while the RF amplifier provides sufficient gain to ensure oscillation. Measurements conducted on the RF-CMOS SAW oscillator demonstrated oscillation at 600 MHz.     

基于LiTaO3基片宽带声表面波滤波器设计方法

通讯系统传输效率的提升对滤波器带宽的要求越来越高,如果使用常规声表面波(SAW)滤波器设计技术,则将面临损耗大或带宽达不到要求的问题。该文根据系列宽带SAW滤波器产品开发结果,总结了采用特殊技术用LiTaO₃压电基片实现相对带宽8%以上的宽带SAW滤波器设计方法,其包括利用外围电感、电容增加SAW谐振器的谐振频率和反谐振频率的间隔,提高阻抗元滤波器带宽;利用多模式纵向耦合谐振滤波器结构增加滤波器带宽;利用双通带滤波器并联结构获得大带宽滤波器。上述方法各有优缺点,其均能获得约为9%的带宽。     

Low Cost Signal Reconstruction Based Testing of RF Components using Incoherent Undersampling

To meet the testing requirements of high speed components used in modern communication systems, in an efficient and cost effective manner, it is necessary to develop new device performance measurement techniques that are easily scalable to high frequencies. Traditional up/down conversion based transmitter testing architectures are sensitive to the linearity of the mixers and carrier phase noise in the receiver. Direct undersampling based test instrumentation can overcome the limitations imposed by mixers in up/down conversion. A major challenge in direct undersampling based test architecture is to achieve precise phase alignment between different components of the test setup. Such phase alignment of high frequency signals requires the use of expensive test instruments adding to the cost and complexity of the overall test system. To resolve this problem, an incoherent undersampling based test method is developed in this research that eliminates the need for precise phase synchronization between the RF test signal carrier, its amplitude-modulated envelope (generally necessary for measuring amplifier nonlinearity) and the reference sampling clock. A side-benefit, due to the use of signal undersampling, is that signal acquisition is achieved without the use of a Nyquist rate data converter. Multiple RF performance metrics are extracted without the use of a reference receiver. The accuracy of the proposed setup is compared against existing coherent sampling based test setups.     

射频SAW器件非线性信号的测量及产生机制分析

射频前端的高度集成和高能量密度使声表面波(SAW)器件的非线性问题愈发严重。该文搭建了射频SAW器件非线性信号的测量系统,对SAW谐振器的二次谐波(H2)和三次谐波(H3)信号进行了准确测量。分析测量结果,讨论了非线性谐波信号的产生机制,并通过非线性有限元(FEM)模型仿真结果与测量结果拟合对比,验证了介电非线性和声应变的非线性效应对谐波产生的影响,为进一步研究非线性抑制方法,设计高线性度SAW器件提供了重要支撑。     

基于LGS的高温无线声表面波传感系统的研究

高温环境下供电和导线联接困难，一般电子元件难以正常工作，因此高温环境下温度、压力等物理量的监测一直是一项较难解决的技术难题。新兴的硅酸钾镧(LGS)压电晶体具有良好的压电和高温特性，为声表面波(SAW)传感器的高温应用提供了可能。该文分析了新兴LGS压电晶体的高温及SAW特性，讨论了它在高温无线无源传感方面的应用途径和关键问题。初步的实验证明了基于LGS的高温SAW无线无源传感系统的可行性。     

Reconfigurable multilayer dual-mode bandpass filter based on memristive switch

A novel memristor-based multilayer dual-mode resonator is presented, which is suitable for the design of reconfigurable multi-band filters. The memristor is used as an RF/microwave switch. A dual-band bandpass filter is realized with the proposed memristor-based dual-mode resonators. The corresponding memristor setup circuitry is optimized in order to minimize the circuitry influence on the desired filter frequency response.     

SAW滤波器自动测试系统设计

针对声表面波(SAW)滤波器测试参数较多,仪器设置较复杂,且封装尺寸不断缩小,传统人工测试效率低,可靠性也不能满足要求等问题。该文利用国内定制的自动测试机,基于LabVIEW软件实现表面贴装器件(SMD)封装的SAW滤波器的自动测试系统。结果表明,该测试系统可实现SMD的自动上料、测试和记录数据,并自动分离不合格品,测试速度约1 000只/h,满足研发及小批量生产的需求。     

Surface Wave Device Applications in Microwave Communication Systems

The application of certain prototype devices, already realized in the complementary surface acoustic wave (SAW) and magnetostatic wave (MSW) technologies, is examined in the context of analogue and digital microwave communications equipments. The specifications of Gaussian response IF bandpass filters and satellite channel multiplexing filters are detailed in the context of SAW designs. Extensions of SAW filter technology to the construction of IF remodulating modems incorporating frequency modulated oscillators and discriminators are examined. Stable SAW oscillators are also reviewed in the context of lightweight, rugged, spacequalified local oscillator drives. The application of MSW technology to the design of a group delay equalizer for millimetric waveguide long-haul digital communications equipments is surveyed. Finally, the paper addresses the design of fixed and variable delay lines realized in both technologies, and SAW code generators, for application to path-length equalization and test{ng of high data rate microwave radio relay systems, respectively.     

Development and model-based transparency analysis of an Internet-distributed hardware-in-the-loop simulation platform

This paper summarizes efforts to integrate, for the first time, two geographically dispersed hardware-in-the-loop simulation setups over the Internet in an observer-free way for an automotive application. The two setups are the engine-in-the-loop simulation setup at the University of Michigan (UM) in Ann Arbor, MI, USA, and the driver-in-the-loop ride motion simulator at the US Army Tank-Automotive Research, Development and Engineering Center (TARDEC) in Warren, MI, USA. The goal of such integration is to increase the fidelity of experiments and to enable concurrent geographically dispersed systems engineering. First, experiments with the actual hardware are presented. The concept of transparency is discussed, and the infeasibility of performing a baseline experiment with ideally integrated hardware is presented as a challenge to characterize the transparency of the experimental setup. This motivates the second half of the paper, in which a model-based approach is taken to analyze the transparency of the system. The conclusion is that an observer-free solution is feasible for integrating the two pieces of hardware over the Internet in a transparent manner, even if the nominal delay is increased by four times. It is also found that different signals in the system can exhibit different levels of transparency.     

Low-Cost Specification Based Testing of RF Amplifier Circuits using Oscillation Principles

In this paper, we propose a low-cost approach for testing GHz RF amplifiers. It is demonstrated for the first time that GHz RF amplifiers can be tested for their specifications using oscillation principles. In the test mode, the RF test signal is “self generated” by the amplifier with the help of additional external circuitry which forces the amplifier to oscillate (Barkhausen criterion) around its characteristic frequency. The RF sinusoidal output from the oscillating RF amplifier is down-converted to a lower frequency enabling low frequency test response analysis as well as increased sensitivity to parametric deviations. In addition to the detection of catastrophic failures, it is shown that multiple RF specifications (Gain, P1dB, and Noise Figure) can be predicted via analysis of the frequency of the down-converted response. To account for RF parasitics on the production floor, a calibration technique is proposed in the test-setup. Thus, the proposed method reduces test cost significantly by reducing the cost of test setup (by as much as 80%) and significantly reducing test time. The viability of the proposed test method is demonstrated both by simulation experiments and measurement.