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A Low-Cost and Low-Power CMOS Receiver Front-End for MB-OFDM Ultra-Wideband Systems要该文全文，更换别的论文，或要中英文对照都可以找我Mahim Ranjan, Member, IEEE, and Lawrence E Larson, Fellow, IEEE0Abstract—This paper presents an RF receiver front-end for MB-OFDM-based ultra-wideband (UWB) The receiver occupies only 35 in a 18 CMOS process and consists of a low-noise amplifier, downconverter and a bandpass There are no on-chip inductors and the receiver requires no off-chip matching The measured receiver gain is 21 dB, noise figure is less than 6 dB, input IIP3 is 6 dBm, and the receiver consumes 5 mA from a 3 V The receivercovers all the MB-OFDM bands from 1 to 8 GHIndex Terms—CMOS, distortion, OFDM, receiver, ultra wideband, UWBI INTRODUCTIONULTRA-WIDEBAND (UWB)multi-band orthogonal frequency-division multiplexing (MB-OFDM) systems have been proposed as an emerging solution to wireless communicationapplications requiring high data rates (up to 480 Mb/s) over short In one proposed version [1], the carrier, with a bandwidth of 528 MHz, can hop to one of 14 channels（2904+528n,n=123…14）, divided into four groups of three channels and one group of two This representative time-frequency interleaving for a Group 1-only systemis depicted in F Design of a receiver for such a systempresents many challenges due to the wide bandwidth of the RF front- However, to assure the widest possible adoption, RF portions of these systems should consume little DC power and die area, and be implemented in a standard CMOS These last requirements argue against the use of on-chip inductors wherever Since theUWBfront-end intrinsically possesses a wide bandwidth, it is open to reception of undesired narrowband signals such as 11 a/b/g and the recently proposedWiMAX [2] systems, as shown in F Although OFDM systems are less susceptible to relatively narrowband jammers, nonlinearities in the receiver can result in jammer cross-modulation with wideband input signals, resulting in reduced signal-to-noise ratio (SNR) and a degradation in system performance [3] In addition, received wideband signals (from other UWB transmitters) can intermodulate and the resulting products can land in a desired Since the system is inherently wideband, harmonic distortion of a single unwanted UWB transmitter can also produce in-band distortion products and reduce the SNR For the system to successfully operate in such a hostile environment, the linearity specifications of the receiver need to include these distortion F Representative time-frequency interleaving pattern of a Group 1MB-OFDM signal [1] F Representative spectrum at an MB-OFDM receiver This paper describes a UWB heterodyne receiver front-end that is designed to minimize the effects of wideband jammers from a variety of undesired sources [4] In addition, the receiver is designed to minimize silicon area, so on-chip inductors are not The receiver architecture is presented in Section II Specifications for the receiver are derived in Section III Detailed block design is presented in Sections IV–VI Layout and packaging of the chip is discussed in Section VII Measured results are presented in Section VIII, followed by a conclusion in Section IXII RECEIVER ARCHITECTUREWhen it comes to designing a low-power and low-cost receiver, the traditional choice is a direct conversion However, a direct conversion UWBreceiver, while attractive for power consumption and simplicity of its local oscillator (LO) scheme [5], [6], has a well-known problem of time-varying DC offset and sensitivity to narrowband A DC offset at the output of the receiver can degrade the SNR of the digitized baseband In addition, it can introduce second-order distortion in the baseband signal, which further degrades the SNR A Low-Cost and Low-Power CMOS Receiver Front-End for MB-OFDM Ultra-Wideband SystemsMahim Ranjan, Member, IEEE, and Lawrence E Larson, Fellow, IEEE0Abstract—This paper presents an RF receiver front-end for MB-OFDM-based ultra-wideband (UWB) The receiver occupies only 35 in a 18 CMOS process and consists of a low-noise amplifier, downconverter and a bandpass There are no on-chip inductors and the receiver requires no off-chip matching The measured receiver gain is 21 dB, noise figure is less than 6 dB, input IIP3 is 6 dBm, and the receiver consumes 5 mA from a 3 V The receivercovers all the MB-OFDM bands from 1 to 8 GHIndex Terms—CMOS, distortion, OFDM, receiver, ultra wideband, UWBI INTRODUCTIONULTRA-WIDEBAND (UWB)multi-band orthogonal frequency-division multiplexing (MB-OFDM) systems have been proposed as an emerging solution to wireless communicationapplications requiring high data rates (up to 480 Mb/s) over short In one proposed version [1], the carrier, with a bandwidth of 528 MHz, can hop to one of 14 channels（2904+528n,n=123…14）, divided into four groups of three channels and one group of two This representative time-frequency interleaving for a Group 1-only systemis depicted in F Design of a receiver for such a systempresents many challenges due to the wide bandwidth of the RF front- However, to assure the widest possible adoption, RF portions of these systems should consume little DC power and die area, and be implemented in a standard CMOS These last requirements argue against the use of on-chip inductors wherever Since theUWBfront-end intrinsically possesses a wide bandwidth, it is open to reception of undesired narrowband signals such as 11 a/b/g and the recently proposedWiMAX [2] systems, as shown in F Although OFDM systems are less susceptible to relatively narrowband jammers, nonlinearities in the receiver can result in jammer cross-modulation with wideband input signals, resulting in reduced signal-to-noise ratio (SNR) and a degradation in system performance [3] In addition, received wideband signals (from other UWB transmitters) can intermodulate and the resulting products can land in a desired Since the system is inherently wideband, harmonic distortion of a single unwanted UWB transmitter can also produce in-band distortion products and reduce the SNR For the system to successfully operate in such a hostile environment, the linearity specifications of the receiver need to include these distortion
HDB3 yards ( third-order high-density dual polarity yards) is the most commonly used in modern transmission system is one of the MaXing, is widely This study is based on the main content of the HDB3 yards encoder CPLD device First of HDB3 yards and CPLD application and research status were introduced, This paper used to MaxPlusII and VHDL language software, Finally HDB3 yards are analyzed in detail by VHDL language encoding principle and realization Based on the principle of coding HDB3 yards, the paper analyzes the design scheme of HDB3 code design mainly divided into three coder realized module ( insert V module, modeling and realize the modeling and realization, B module modeling and realize polarity transform module) After completion, the software design in the simulation, MaxPlus2 test results and the design idea of early, so right, completed based on simulation HDB3 code design of CPLD
PickHDB3 yards ( third-order high-density dual polarity yards) is the most commonly used in modern transmission system is one of the MaXing, is widely This study is based on the main content of the HDB3 yards encoder CPLD device First of HDB3 yards and CPLD application and research status were introduced, This paper used to MaxPlusII and VHDL language software, Finally HDB3 yards are analyzed in detail by VHDL language encoding principle and realization Based on the principle of coding HDB3 yards, the paper analyzes the design scheme of HDB3 code design mainly divided into three coder realized module ( insert V module, modeling and realize the modeling and realization, B module modeling and realize polarity transform module) After completion, the software design in the simulation, MaxPlus2 test results and the design idea of early, so right, completed based on simulation HDB3 code design of CPLD Keywords: HDB3, VHDL, Polarity transformation
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1、蓝牙简介早在1994年，Ericsson公司就在其内部提出了一项研究计划，旨在建立发展一种能简易使用并可在各种通讯设备上畅行无阻的新一代无线传输技术，建立一个实际的无线接口和相关软件标准。1998年，Ericsson公司公开了这项计划，并与Nokia、IBM、Toshiba和Intel四家公司组成了一个特别利益集团（SIG，Special Interest Group），以负责此项技术的开发。一年后的1999年7月，SIG正式提出了该技术协议的0版，并将此项技术命名为蓝牙（Bluetooth）。据SIG官方说明，蓝牙这个名字来自十世纪丹麦的维京族国王Harald Bluetooth。这位国王曾以武力统一了丹麦和挪威，在斯堪的那维亚半岛建立了一个庞大的帝国。蓝牙技术解决了小型移动设备间的无线互连问题。它的硬件市场非常广阔，涵盖了局域网络中的各类数据及语音设备。该技术的本质目的不是成为另一种无线局域网（WLAN）技术，而是成为一种替代传输电缆的新型无线解决方案。从1999年的0版，到后来的1版、2版、0版，蓝牙技术不断地在技术上完善自身，力图吸取通用电缆在成本、安全和承载能力等方面的优势。在Bluetooth国王叱咤北欧的千年之后，新兴的蓝牙技术正在以其的种种优势，在全球的无线连接市场中开拓比Bluetooth国王大上千倍万倍的疆土。2、蓝牙协议概述蓝牙体系结构中的协议模型可分为以下5层：（1） 物理层：蓝牙协议的无线接口层；（2） 核心协议：基带协议（Baseband）、链路管理协议（LMP）、逻辑链路控制和适配协议（L2CAP）、服务发现协议（SDP）等。基带协议可以提供同步面向连接（SCO）业务和非同步连接（ACL）业务。一般地，SCO用于分组数据业务，其特点是可靠，但有延时；而ACL用于话音传送，其特点是实时性好。但可靠性比SCO差。链路管理协议（LMP）负责建立和解除主、从设备单元之间的连接，另外还控制主、从设备单元的工作模式。L2CAP是第三层的控制和适配协议，L2CAP向RFCOMM和SDP等层提供面向连接和无连接业务。基带数据业务可以越过LMP而直接通过L2CAP向高层协议传送数据。从某种意义上说，L2CAP和LMP都相当于OSI第二层即链路层的协议；
蓝牙技术是一种近距离、低功耗的无线通信标准，它为设备提供了一种低成本的无线联网方式。本文介绍了蓝牙技术中的底层模块、协议以及应用模型，并将它与其他常用的无线连接技术做了比较，以说明它的优势所在。关键词：蓝牙；底层模块；协议；应用1、蓝牙简介早在1994年，Ericsson公司就在其内部提出了一项研究计划，旨在建立发展一种能简易使用并可在各种通讯设备上畅行无阻的新一代无线传输技术，建立一个实际的无线接口和相关软件标准。1998年，Ericsson公司公开了这项计划，并与Nokia、IBM、Toshiba和Intel四家公司组成了一个特别利益集团（SIG，Special Interest Group），以负责此项技术的开发。一年后的1999年7月，SIG正式提出了该技术协议的0版，并将此项技术命名为蓝牙（Bluetooth）。据SIG官方说明，蓝牙这个名字来自十世纪丹麦的维京族国王Harald Bluetooth。这位国王曾以武力统一了丹麦和挪威，在斯堪的那维亚半岛建立了一个庞大的帝国。蓝牙技术解决了小型移动设备间的无线互连问题。它的硬件市场非常广阔，涵盖了局域网络中的各类数据及语音设备。该技术的本质目的不是成为另一种无线局域网（WLAN）技术，而是成为一种替代传输电缆的新型无线解决方案。从1999年的0版，到后来的1版、2版、0版，蓝牙技术不断地在技术上完善自身，力图吸取通用电缆在成本、安全和承载能力等方面的优势。在Bluetooth国王叱咤北欧的千年之后，新兴的蓝牙技术正在以其的种种优势，在全球的无线连接市场中开拓比Bluetooth国王大上千倍万倍的疆土。2、蓝牙协议概述蓝牙体系结构中的协议模型可分为以下5层：（1） 物理层：蓝牙协议的无线接口层；（2） 核心协议：基带协议（Baseband）、链路管理协议（LMP）、逻辑链路控制和适配协议（L2CAP）、服务发现协议（SDP）等。基带协议可以提供同步面向连接（SCO）业务和非同步连接（ACL）业务。一般地，SCO用于分组数据业务，其特点是可靠，但有延时；而ACL用于话音传送，其特点是实时性好。但可靠性比SCO差。链路管理协议（LMP）负责建立和解除主、从设备单元之间的连接，另外还控制主、从设备单元的工作模式。L2CAP是第三层的控制和适配协议，L2CAP向RFCOMM和SDP等层提供面向连接和无连接业务。基带数据业务可以越过LMP而直接通过L2CAP向高层协议传送数据。从某种意义上说，L2CAP和LMP都相当于OSI第二层即链路层的协议；（3） 射频通信协议：RFCOMM，它可以仿真串行电缆接口协议。通过RFCOMM，蓝牙可以在无线环境下实现对高层协议如PPP、TCP/IP、WAP等的支持。RFCOMM可以支持AT命令集，从而可以实现移动电话和传真机及调制解调器之间的无线连接；（4） 电话传送控制协议：TCS二进制协议、AT命令集等；（5） 应用协议（可选协议）：PPP（点对点协议）、UDP／TCP／IP、OBEX、vCard/vCarl、FAX、PAN等。3、蓝牙底层模块蓝牙底层模块是蓝牙技术的核心，是任何蓝牙设备都必须包括的部分。1射频为了保证系统所需频带是全球各地均能容易地获得的，蓝牙系统工作在大多数国家的工业、科学、医疗（ISM）频率——即4GHz。由于ISM频带的开放性，使用其中任一频段都会遇到不可预测的工扰——比如说，家用的无线电话、微波炉都可能成为干扰源。为此，蓝牙特别设计了快速确认和跳频方案以确保链路稳定。蓝牙将其工作的402GHz～480GHz的频带分为79个1MHz带宽的子信道，在接收或发送一个分组数据后，即跳至另一频点，因而加强了数据传输的稳定性。跳频技术除了为蓝牙技术提供了稳定性保障以外，还在物理层为其安全性提供了保障。在跳频通信中，数据信号被窄带载波信号调制，而这些窄带载波信号则做为时间的函数不断从一个频率跳到另一频率。蓝牙标准采用的是每秒跳跃1600次的跳频序列。收发双方都知道的跳频码决定了射频载波的频率以及跳频的顺序。为正确地进行信号接收，接收器必须设置成与发送方一样的跳频码，并在恰当的时间和正确的频率点监听载波信号。只有正确同步时，才能维持一个逻辑信道。其他没有同步的接收器收到的信号仅是持续时间极短的脉冲噪声，这就使得窃听变得十分困难。
大学毕业论文电子信息工程技术如果是程序代码,我可以帮你写,如果是打字工作,你还是自己做吧,毕竟书还是给自己读的,祝你顺利毕业,没联系方式,真找不到你了,来找我吧,合作愉快,请注意查收消息,毕业了别忘了给分呵
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最低工资委员会的操作数=2渠道和采样率=1财政司司长/>对每个通道，所以它的方法的最小速度2nb。先进的配置使附加硬件储蓄所倒塌的分行数目的一个因素，问为代价的增加，每个通道采样率由同一因素[ 109]。选择周期函数皮（吨）是灵活的：最高的狄拉克频率超过25。原则上，任何周期函数与高速内过渡的时期可以满足这一要求。一个可能的选择皮（吨）是一个注册交替作用，米=2+ 1符号间隔在期[ 109，161 ]。不完美的标志还允许只要维持周期是[ 9 ]。此属性是至关重要的准确标志交替高速度是极难维持，而简单的硬件接线确保皮（吨）=π（吨+普瑞尔）每2R波形皮（吨）需要低相互相关为了捕捉不同的混合物的光谱。流行的二进制模式，例如，黄金或kasami序列，尤其适用于康复[ 161]。另一个重要方面是，低通滤波器的实用设计过滤器小时（吨）不一定是理想的。一个非平坦的频率响应可以补偿在数字域，使用方法[ 162]。