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A LOW EVM zero-if RF TRANSMITTER FOR COGNITIVE RADIO APPLICATION

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Journal of Electronics(China) 2010年第5期27卷 723-727页

作者： Zhang Xiaodong Zhu Xiaowei Liu Jing You Changjiang State Key Lab of Millimeter Waves Southeast UniversityNanjing 210096China

A zero-if transmitter for Cognitive Radio(CR) application is *** effectively reduce the interference between Power Amplifier(PA) and Voltage Controlled Oscillator(VCO),two VCOs are adopted,one is 450 MHz and the other is from 1148 MHz to 1252 MHz with an 8 MHz step,so the frequency of them are different from the operational frequency of *** Local Oscillator(LO) of the modulator generated by mixing the signals of the two VCOs has a low phase noise of-82 dBc/Hz with an offset of 1 *** measurement result of the transmitter shows that the Adjacent Channel Power Ratio(ACPR) is less than-47.5 dBc at 27 dBm output,and the Error Vector Magnitude(EVM) is less than 1.7%.

关键词： Cognitive Radio (CR) zero-if Transmitter Error Vector Magnitude (EVM)

A transformer-loaded receiver front end for 2.4 GHz WLAN in 0.13μm CMOS technology

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Journal of Semiconductors 2011年第12期32卷 101-106页

作者：彭苗林敏石寅代伐 Institute of Semiconductors Suzhou-CAS Semiconductors Integrated Technology Research Center Department of Electrical & Computer Engineering Auburn University

A 2.4 GHz radio frequency receiver front end with an on-chip transformer compliant with IEEE 802.11b/g standards is presented. Based on zero-if receiver architecture, the front end comprises a variable gain common-source low noise amplifier with an on-chip transformer as its load and a high linear quadrature folded Gilbert mixer. As the load of the LNA, the on-chip transformer is optimized for lowest resistive loss and highest power gain. The whole front end draws 21 mA from 1.2 V supply, and the measured results show a double side band noise figure of 3.75 dB, -31 dBm IIP3 with 44 dB conversion gain at maximum gain setting. Implemented in 0.13 μm CMOS technology, it occupies a 0.612 mm^2 die size.

关键词： zero-if direct-down-conversion WLAN CMOS RF on-chip transformer

Reconfigurable anti-interference RF transceiver for cognitive radio application

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Journal of Southeast University(English Edition) 2011年第2期27卷 123-127页

作者：游长江柳靖张晓东朱晓维东南大学毫米波国家重点实验室南京210096

An RF transceiver composed of a zero-if receiver and a direct up-conversion transmitter for cognitive radio applications is presented. The adjustable channel filter array in the receiver is used to suppress adjacent channel interference in televisions signal coexistence environments. The low noise amplifier （LNA） with wide dynamic range and high linearity is employed to enhance the anti-interference competence of the zero-if receiver. Meanwhile, the high linearity power amplifier （PA） .is used to promote the adjacent channel power ratio （ACPR） characteristic of the direct up-conversion transmitter. The measured error vector magnitude （EVM） results show that the anti-interference competence of the zero-if receiver is dramatically enhanced by employing a channel filter array. The measured ACPR of the direct up-conversion transmitter is -47. 98 dBc on the channel centered at 714 MHz when the output power is 27 dBm.

关键词： zero-if direct up-conversion anti-interference cognitive radio white space spectrum

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UWB系统零中频超宽带接收机设计

UWB系统零中频超宽带接收机设计

作者：冯立松中国科学技术大学

学位级别：硕士

UWB(超宽带)是一种以极低功率在短距离内高速传输数据的无线技术。这种技术原服役于军方,后来被FCC(美国联邦通信委员会)正式批准民用从而备受关注。UWB技术是一种极具竞争力的短距无线高速通信技术。作为UWB通信系统的核心模块,射频... 详细信息

UWB(超宽带)是一种以极低功率在短距离内高速传输数据的无线技术。这种技术原服役于军方,后来被FCC(美国联邦通信委员会)正式批准民用从而备受关注。UWB技术是一种极具竞争力的短距无线高速通信技术。作为UWB通信系统的核心模块,射频接收机越来越多的受到人们的关注。本文重点在实现一个低功耗,低噪声,高线性度的零中频射频接收机。本课题从UWB无线通信标准出发,采用自顶向下的设计方法,主要从噪声与线性度两方面考虑,将系统的性能指标合理的分配到射频接收机的各个模块。为了消除零中频接收机固有的DC-Offset效应,采用了VGA直流反馈技术,将大的交流耦合电容转移到片外,有效的节省了芯片面积。该设计采用主流的SMIC 0.18um射频CMOS工艺,以COB(Chip On Borad)的方式通过PCB测试,测试结果表明,在3GHz的带宽内,接收机通路增益最高可达47.6dB,最小可检测输入信号-70dBm,输入匹配低于-8dB,本振隔离度为38dB,功耗50mW,该接收机已成功应用于UWB相关接收方案组网试验中,可以清晰流畅传输视频。作为UWB无线接收机的重要组成部分,本文详细的给出了超宽带射频开关、低噪声放大器、混频器的设计过程。从单管开关模型出发,对射频开关的插入损耗进行了定量分析,推导出衬底寄生电阻与插入损耗的关系,给出了优化设计方法。测试结果表明开关插入损耗小于1.9dB,反向隔离度好于-27dB,芯片面积为100u*150u,直流功耗为0mW。对超宽带LNA输入匹配与噪声进行了详细的分析,并给出了平坦增益的实现方法。测试结果表明,在3-5GHz的带宽内,最高增益13.2dB,增益波动为±0.45dB,噪声系数3.2.5dB,输入P1d B压缩点为-11.715.9dBm,芯片面积0.7mm2,功耗17.2mW。超宽带Mixer采用了电感建峰与电流注入技术,并对mixer噪声与线性度进行了详细分析。测试结果表明,在10MGHz的带宽内,功率增益-0.4.1dB,输入P1d B压缩点为-58dBm,功耗为9mW。

关键词：超宽带 CMOS Switch LNA Mixer zero-if Receiver

新一代数字卫星接收机中I/Q不平衡的数字补偿

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有线电视技术 2008年第8期15卷 48-49页

作者：倪小英北京工业大学嵌入式实验室

为了克服零中频结构的卫星接收机产生的I/Q不平衡的影响,本文提出了基于I路信号和Q路信号互相关的数字补偿方法。通过仿真结构可知,该方法能够补偿较大的I/Q增益不平衡和I/Q相位不平衡。

关键词： I/Q不平衡 DVB—S2 zero-if