Methods to reduce radiation from split ground planes in RF and mixed signal packaging structures

Split ground planes are sometimes used in RF and mixed signal packages in order to isolate the RF and analog circuits from the digital circuits. Undesired radiation in a packaging environment may occur when a signal trace is routed over a slot in the ground plane. This paper examines and investigates ways to eliminate signal coupling into split ground plane structures and assesses the impact of this reduced coupling on signal integrity in a packaging environment. Suggested methods to reduce coupling of energy into the slot are to alter the shape of the slot with RF chokes or corrugations.     

Issues and trends in router design

Future routers must not only forward packets at high speeds, but also deal with nontrivial issues such as scheduling support for differential services, heterogeneous link technologies, and backward compatibility with a wide range of packet formats and routing protocols. The authors outline the design issues facing the next generation of backbone, enterprise, and access routers. The authors also present a survey of advances in router design, identifying important trends, concluding with a selection of open issues     

Status and trends of silicon RF technology

The current research and development activities in silicon radio-frequency (RF) technologies are first reviewed, accompanied by an illustration of the most pronounced shortcomings of conventional silicon technology in the integrability of RF functions at high GHz frequencies. In the discussion on active RF devices mainly CMOS is investigated due to great interest in this mass-production technology. Issues related to the integration of spiral inductors on silicon are addressed, stressing in particular the difficulty of RF substrate potential definition. Silicon micromachining techniques are highlighted as potential solutions to the integration of RF passives and to reduce substrate losses and cross-talk on silicon. It is explained that micromachining techniques are the best introduced to the silicon mainstream by using post-processing and minimum process complexity.     

一种射频信号干扰器的设计

为了测试电子设备的抗干扰能力,设计了一种射频信号干扰器,可用于产生406.0～406.1 MHz范围内的随机干扰、点频干扰和扫频干扰信号.设计采用了直接数字频率合成（DDS）技术,通过单片机对DDS芯片的控制,可灵活产生需要的干扰频率.     

Performance trends of Si-based RF transistors

This paper discusses several aspects of the performance of advanced Si-based RF transistors. The RF performance of SiGe HBTs and Si RF MOSFETs is reviewed and compared to that of III–V RF transistors. The speed – breakdown voltage tradeoff which is typical for bipolar transistors is discussed with special emphasis on SiGe HBTs. On the field-effect transistor side, we review the performance of state-of-the-art Si RF MOSFETs and show that these devices are highly competitive in terms of speed and cutoff frequency.     

Future trends in wafer scale integration

The dramatic increase in the functional density of VLSI has been achieved without greatly increasing the chip size. In wafer scale integration, the area of an entire wafer is made available to increase the functional density still further. However, the requirement for fault tolerance, additional levels of metallization, excess power dissipation, process conservatism to achieve finite yield, and nonoptimum nature of the AI/SiO2transmission line for cross-wafer communication have made WSI noncompetitive with state-of-the-art VLSI and dense multichip hybrid packaging approaches, at least so far. On the other hand, the potential benefits of WSI are great. Chief among them is the greatly increased expected reliability, which is partly due to an all-monolithic system and partly because of the hope that fault tolerance, which is an absolute requirement for WSI fabrication, can be extended to failure tolerance, and thus the ability to reconfigure during systems operation, and perhaps even transparent to it. Pipeline- or bus-oriented logic structures were found to be the most promising for WSI implementation.     

SoC Issues for RF Smart Dust

Wireless sensor nodes are autonomous devices incorporating sensing, power, computation, and communication into one system. Applications for large scale networks of these nodes are presented in the context of their impact on the hardware design. The demand for low unit cost and multiyear lifetimes, combined with progress in CMOS and MEMS processing, are driving development of SoC solutions for sensor nodes at the cubic centimeter scale with a minimum number of off-chip components. Here, the feasibility of a complete, cubic millimeter scale, single-chip sensor node is explored by examining practical limits on process integration and energetic cost of short-range RF communication. Autonomous cubic millimeter nodes appear within reach, but process complexity and substantial sacrifices in performance involved with a true single-chip solution establish a tradeoff between integration and assembly.     

新型RSA系列的实时频谱分析仪

RSA系列实时频谱分析仪采用了实时频谱分析技术,为开发射频技术的工程师提供了一个完整的测量套件,包括RF标识(ID)标记应用到完善的雷达应用。实时频谱分析为触发、捕获和分析随着时间变化的RF信号提供了独特的解决方案。这些仪器通过触发扫频分析仪     

蜂窝基站测试中的射频信号取样

从系统角度出发,主要讨论蜂窝基站测试的射频信号的取样问题.根据国标中的相关要求,通过实验比较讨论衰减器和耦合器的非线性特性,从理论和实验结果进行分析并得出结论.     

一种应用于射频卡的集成稳压电路的设计

介绍了一种应用于射频卡中稳压电路的设计方案，分析了该电路各个模块的结构和整个电路的工作过程，用HSPICE对其进行了模块仿真验证，并进行了多目标流片，测试结果达到了设计要求，表明该稳压电路可以应用于射频卡芯片中。     

GPS接收机应用于手机中所遇到的射频干扰

将GPS接收机嵌入到手机硬件中,GPS接收频率将与手机中其它射频源共存.这些射频源包括GSM,UMTS,WLAN和Bluetooth.指出这些射频源对GPS接收信号的干扰程度,以明确哪种射频源对GPS接收机的阻塞影响最大,成为提出相应的解决方案是关键.验证方法主要是由Texas Instrument提供的GPS评估板接收来自GPS卫星模拟器发出的GPS信息,由具备GSM,UMTS,WLAN,Bluetooth功能的手机分别对GPS评估板发出不同的射频传导信号.结果证明:主要验证了UMTS1 900 MHz作为手机发射源时,对GPS接收机的阻塞影响最大,对改善GPS接收机带通滤波器的性能,为抑制UMTS信号起到很好的作用.     

RF signal component separator for LINC transmitters

An experimental test bed of a novel full analogue microwave LINC signal component separator scheme is presented. The proposed experiment has been performed to validate the theory and to demonstrate the usefulness of the proposed solution, constituting the preliminary and mandatory step before a completely integrated version.     

将RF信号转换为数字信号的CMOS转换器

从频率计数与合成到传感器信号调整等很多应用都需要将RF信号转换为数字逻辑电平。在这些情况下,设计者一般采用一个高速电压比较器完成RF到数字信号的转换工作。由于电压比较器具有高增益,它们一般有很好的灵敏度,但也会带来一些问题。高速比较器价格高,很难找到现成的商品,并且易于被快速淘汰。     

MIM capacitor integration for mixed-signal/RF applications

The relentless drive toward high-speed and high-density silicon-based integrated circuits (ICs) has necessitated significant advances in processing technology. The entrance of copper metallization in IC manufacturing has resulted in new challenges in metal-insulator-metal (MIM) capacitor fabrication, one of the key building blocks in analog/mixed signal/RFCMOS circuits. The requirement to reduce passive chip space has led to active researches for MIM with high dielectric constant (/spl kappa/) film. This paper provides an overview of MIM capacitor integration issues with the transition from AlCu backend of line (BEOL) to Cu BEOL. The key to MIM capacitor electrical properties can be achieved with optimized dielectrics. The different MIM capacitor architectures published are also described. Special emphasis is made on the properties of various MIM with high-/spl kappa/ dielectrics in the last section.     

射频解决方案提升手机芯片集成度

随着嵌入高级多媒体功能集的手机数量日益增加，无线装置的体积、功耗、设计灵活性和总成本这几项因素越来越重要。在5月召开的手机配套采购会上，Skyworks(思佳讯)公司首次在内地展示了其面向GPRS、WCDMA、TD-SCDMA、EDGE等平台的前端模组及射频解决方案。     

Predicting RF coverage in large environments using ray-beam tracing and partitioning tree represented geometry

We present a system for efficient prediction of RF power distribution in site specific environments using a variation of ray tracing, which we calledray-beam tracing. The simulation results were validated against measured data for a number of large environments with good statistical correlation between the two. We represent geometric environments in full 3D which facilitates rooftop deployment along with any other 3D locations. We use broadcast mode of propagation, whose cost increases more slowly with an increase in the number of receiving bins. The scheme works well both for indoor and outdoor environments. Simple ray tracing has a major disadvantage in that adjacent rays from a transmitter diverge greatly after large path lengths due to multiple reflections, such that arbitrarily large geometric entities could fall in between these rays. This results in asampling error problem. The error increases arbitrarily as the incident angle approaches 90°. The problem is addressed by introducing the notion of beams while retaining the simplicity of rays for intersection calculations. A beam is adaptively split into child beams to limit the error. A major challenge for computational efficiency is to quickly determine the closest ray-surface intersection. We achieve this by using partitioning trees which allows representation of arbitrarily oriented polygonal environments. We also use partitioning trees for our full 3D interactive visualization along with interactive placement of transmitters, receiving bins, and querying of power.     

一种通用雷达射频信号模拟器设计与实现

为了改进目前检测雷达告警设备的多波段分立式雷达射频信号模拟器,采用PC104＋CPLD设计了一种通用雷达射频信号模拟器,创新地设计了分频功率回退谐波抑制方法。根据电子对抗接收机的工作特性,模块化雷达射频信号模拟器的结构组成,并对各模块进行了优化设计。实践证明该模拟器具有良好的通用性和可扩展性。     

射频干扰对消技术在通信系统集成中的应用

介绍了射频干扰对消技术的原理和系统模型,总结了其实现的关键技术点,指出了在通信系统集成中以及任务系统集成中的应用,以及宽带和大动态等未来的发展方向。     

InGaP HBT 大信号RF功率传输特性

本文实验研究了用于RF功率放大器的先进的InGaP HBT 器件大信号RF功率传输特性。研究了InGaP HBT在小信号和大信号状态下输出端的发射功率和反射功率及输入端的反射功率的规律。分析了InGaP HBT RF功率信号的多频率功率成份及其对大信号功率增益压缩,非线性和RF输出功率饱和的影响。