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1.
This paper reviews and analyses various simplified-RFID (Radio Frequency Identification) indoor location systems, and proposes an improved implementation based on the propagation channel "fingerprinting" principle. The focus of the design aims to provide accurate location estimation, while minimising infrastructural requirements. The proposed approach is based on the LANDMARC (Indoor Location Sensing Using Active RFID) with Virtual Reference tags (VIRE) and implemented with dynamic linear interpolation and ...  相似文献   

2.
Embedded digital signal processors for software defined radio have stringent design constraints including high computational bandwidth, low power consumption, and low interrupt latency. Furthermore, due to rapidly evolving communication standards with increasing code complexity, these processors must be compiler-friendly, so that code for them can quickly be developed in a high-level language. In this paper, we present the design of the Sandblaster Processor, a low-power multithreaded digital signal processor for software defined radio. The processor uses a unique combination of token triggered threading, powerful compound instructions, and SIMD vector operations to provide real-time baseband processing capabilities with very low power consumption. We describe the processor’s architecture and microarchitecture, along with various techniques for achieving high performance and low power dissipation. We also describe the processor’s programming environment and the SB3010 platform, a complete system-on-chip solution for software defined radio. Using a super-computer class vectorizing compiler, the SB3010 achieves real-time performance in software on a variety of communication protocols including 802.11b, GPS, AM/FM radio, Bluetooth, GPRS, and WCDMA. In addition to providing a programmable platform for SDR, the processor also provides efficient support for a wide variety of digital signal processing and multimedia applications. Michael Schulte received a B.S. degree in Electrical Engineering from the University of Wisconsin-Madison in 1991, and M.S. and Ph.D. degrees in Electrical Engineering from the University of Texas at Austin in 1992 and 1996, respectively. From 1996 to 2002, he was an assistant and associate professor at Lehigh University, where he directed the Computer Architecture and Arithmetic Research Laboratory. He is currently an assistant professor at the University of Wisconsin-Madison, where he leads the Madison Embedded Systems and Architectures Group. His research interests include high-performance embedded processors, computer architecture, domain-specific systems, computer arithmetic, and wireless systems. He is a senior member of the IEEE and the IEEE Computer Society, and an associate editor for the IEEE Transactions on Computers and the Journal of VLSI Signal Processing. John Glossner is CTO & Executive Vice President at Sandbridge Technologies. Prior to co-founding Sandbridge, John managed the Advanced DSP Technology group, Broadband Transmission Systems group, and was Access Aggregation Business Development manager at IBM’s T.J. Watson Research Center. Prior to IBM, John managed the software effort in Lucent/Motorola’s Starcore DSP design center. John received a Ph.D. in Computer Architecture from TU Delft in the Netherlands for his work on a Multithreaded Java processor with DSP capability. He also received an M.S. degree in Engineering Management and an M.S.E.E. from NTU. John also holds a B.S.E.E. degree from Penn State. John has more than 60 publications and 12 issued patents. Dr. Sanjay Jinturkar is the Director of Software at Sandbridge and manages the systems software and communications software groups. Previously, he managed the software tools group at StarCore. He has a Ph.D in Computer Science from University of Virginia and holds 20 publications and 4 patents. Mayan Moudgill obtained a Ph.D. in Computer Science from Cornell University in 1994, after which he joined IBM at the Thomas J. Watson Research Center. He worked on a variety of computer architecture and compiler related projects, including the VLIW research compiler, Linux ports for the 40x series embedded processors and simulators for the Power 4. In 2001, he co-founded Sandbridge Technologies, a start-up that is developing digital signal processors targeted at 3G wireless phones. Suman Mamidi is a graduate student in the Department of Electrical and Computer Engineering at the University of Wisconsin-Madison. He received his M.S. degree from the University of Wisconsin-Madison in December, 2003 and is currently working towards his PhD. His research interests include low-power processors, hardware accelerators, multithreaded processors, reconfigurable hardware, and embedded systems. Stamatis Vassiliadis was born in Manolates, Samos, Greece, in 1951. He is currently a Chair Professor in the Electrical Engineering, Mathematics, and Computer Science (EEMCS) department of Delft University of Technology (TU Delft), The Netherlands. He previously served in the Electrical and Computer Engineering faculties of Cornell University, Ithaca, NY and the State University of New York (S.U.N.Y.), Binghamton, NY. For a decade, he worked with IBM, where he was involved in a number of advanced research and development projects. He received numerous awards for his work, including 24 publication awards, 15 invention awards, and an outstanding innovation award for engineering/scientific hardware design. His 73 USA patents rank him as the top all time IBM inventor. Dr. Vassiliadis is an ACM fellow, an IEEE fellow and a member of the Royal Netherlands Academy of Arts and Sciences (KNAW).  相似文献   

3.
This paper studies the use of optimum combining to increase the capacity of narrow-band in-building radio communication systems with multiple users. We consider systems consisting of a base Station with numerous remotes in a Rayleigh fading environment and study the problem of more users requiring channels than the number of channels available. A system is described that, with multiple antennas at the base station but only one antenna at each remote, uses optimum combining to suppress interfering signals. We show that this system, withMantennas at the base station, can achieve anM-fold increase in the number of users or tolerateM - 1interferers from other systems. Thus, with optimum combining, radio communications can be used in high-density, multiple-user environments, such as within buildings, even when only limited bandwidth is available.  相似文献   

4.
张清  毕光国 《电子学报》1996,24(1):63-67
本语言分析了室内无线多径衰落信道中差分网格编码调制直扩多址通信系统的性能,分析中采用特征函数法和留数定理计算序列差错概率,用高斯近似分析多址干扰和多径干扰,本文最后给出了误码率的理论分析结果和计算机模拟结果,并与常规的未编码直扩系统性能对比。  相似文献   

5.
Power consumption is a critical issue in many wireless sensor network scenarios where network life expectancy is measured in months or years. Communication protocols typically rely on synchronous operation and duty-cycle mechanisms to reduce the power usage at the cost of decreased network responsiveness and increased communication latency. A low-power radio-triggered device can be used to continuously monitor the channel and activate the node for incoming communications, allowing purely asynchronous operations. To be effective, the power consumption of this wake-up device must be on the order of tens of microwatts since this device is always active. This paper presents our first attempt at designing such a low-power receiver. Very few realizations of wake-up devices are reported in the literature and none presents power dissipation below 40 μW. Our design implements a complete wake-up device and initial results indicate an average power consumption below 20 μW, which is more than 2 times lower than other reported devices.  相似文献   

6.
This letter presents a CMOS double-balanced direct-conversion mixer for ultra-wideband systems. The proposed mixer employs three techniques: the subthreshold operation of transistors for the radio frequency stage reduces current dissipation in the overall mixer, a local oscillation (LO) stage using an inverter lowers the required LO amplitude, and an active load improves conversion gain. The mixer was implemented using a 0.13 $mu{rm m}$ 1P8M CMOS process and was operated from 3.1 to 10.6 GHz. The measured results show a high conversion gain of 14.0 dB and a noise figure of 14.5 dB. In addition, the mixer performs with an input $IP_{3}$ of $-$ 11 dBm and a power dissipation of 1.85 mW from a 1.2 V supply.   相似文献   

7.
The range and impact of SiGe bipolar and BiCMOS technologies on wireless transceivers for portable telephony and data communications are surveyed. SiGe technology enables transceiver designs that compare favorably with competing technologies such as RF CMOS or III-Vs, with advantages in design cycle time and performance versus cost. As wireless devices continue to increase in complexity using conventional battery technology as the power source, the desire to reduce current consumption in future transceivers continues to favor SiGe technology. Examples are drawn from contemporary wireless communications ICs. The performance of on-chip passive components in silicon technologies are also reviewed in this paper. Greater understanding of the limitations of passive devices coupled with improved models for their performance are leading to circuits offering wider RF dynamic range at ever higher operating frequencies. The innovations in on-chip passive design and construction currently being pioneered in mixed-signal SiGe technologies are enabling circuits operating deep into millimeter-wave frequency bands (i.e., well above 30 GHz). In addition, sophisticated on-chip magnetic components combined with deep submicrometer SiGe active devices in a transceiver front end are envisioned that enable single-volt SiGe circuits, with even lower current consumption than is achievable today. Relevant examples from the recent literature are presented.  相似文献   

8.
Utilization of low-power indoor devices such as remote sensors, supervisory and alarm systems, distributed controls, and data transfer system is on steady rise. Due to remote and distributed nature of these systems, it is attractive to avoid using electrical wiring to supply power to them. Primary batteries have been used for this application for many years, but they require regular maintenance at usually hard to access places. This paper provides a complete analysis of a photovoltaic (PV) harvesting system for indoor low-power applications. The characteristics of a target load, PV cell, and power conditioning circuit are discussed. Different choices of energy storage are also explained. Implementation and test results of the system are presented, which highlights the practical issues and limitations of the system.  相似文献   

9.
Distributed Antennas for Indoor Radio Communications   总被引:4,自引:0,他引:4  
The idea of implementing an indoor radio communications system serving an entire building from a single central antenna appears to be an attractive proposition. However, based on various indoor propagation measurements of the signal attenuation and the multipath delay spread, such a centralized approach appears to be limited to small buildings and to narrow-band FDMA-type systems with limited reliability and flexibility. In this paper, we present the results of indoor radio propagation measurements of two signal distribution approaches that improve the picture dramatically. In the first, the building is divided into many small cells, each served from an antenna located in its own center, and with adjacent cells operating in different frequency bands. In the second approach, the building is divided into one or more large cells, each served from a distributed antenna system or a "leaky feeder" that winds its way through the hallways. This approach eliminates the frequency cell handoff problem that is bound to exist in the first approach, while still preserving the dramatic reductions in multipath delay spread and signal attenuation compared to a centralized system. For example, the measurements show that, with either approach, the signal attenuation can be reduced by as much as a few tens of decibels and the rms delay spread becomes limited to 20 to 50 us, even in large buildings. This can make possible the implementation of sophisticated broad-band TDMA-type systems that are flexible, robust, and virtually building-independent.  相似文献   

10.
This paper presents a high gain, low-power common-gate ultra-wideband low-noise amplifier employing a simple configuration for wideband input matching. In our design, a series resistance-inductance network at the source combines with the parasitic capacitance of a transistor to form a parallel RLC input matching configuration in the common-gate input stage. Because of the additional resistance, this matching configuration partially alleviates the restriction of transconductance of the input transistor and also provides wideband matching. The low-noise amplifier was fabricated using the TSMC 0.18  \(\mu \) m technology with an average noise figure of 3.75 dB, a power gain of 18.68 dB with a ripple of \(\pm \)  0.8 dB, an input return loss less than \(-10\)  dB from 3 to 7.6 GHz, and DC power consumption of 8.56 mW, including the output buffer with a 1.8 V supply voltage.  相似文献   

11.
This paper presents an RF receiver front-end for MB-OFDM-based ultra-wideband (UWB) systems. The receiver occupies only 0.35 mm2 in a 0.18 mum CMOS process and consists of a low-noise amplifier, downconverter and a bandpass filter. There are no on-chip inductors and the receiver requires no off-chip matching components. The measured receiver gain is 21 dB, noise figure is less than 6.6 dB, input IIP3 is -5.6 dBm, and the receiver consumes 19.5 mA from a 2.3 V supply. The receiver covers all the MB-OFDM bands from 3.1 to 8 GHz  相似文献   

12.
In this paper, design and implementation of a baseband receiver integrated circuit (IC) for a downlink multi-carrier code-division multiple access (MC-CDMA) system are presented. This MC-CDMA system aims to provide higher data transmission capacity than the current wide-band CDMA systems in mobile cellular communication environments. The proposed chip provides a robust tracking mechanism for synchronization errors and an accurate channel estimation strategy to overcome the challenge of outdoor fast-fading channels. Besides, low-power and low-complexity architecture design techniques are adopted to satisfy mobile receiver needs. Experimental results of the designed baseband receiver integrated circuit demonstrate its superior system performance and great reduction in power consumption. The chip was fabricated in a 0.18-mum CMOS technology with a core area of 2.6 mm times 2.6 mm. It can support up to 21.7-Mbps uncoded data rate in a 5-MHz bandwidth. When running at 5.76 MHz, its power consumption is as low as 9.9 mW from a supply voltage of 1.1 V.  相似文献   

13.
基于传播损耗模型的最大似然估计室内定位算法   总被引:3,自引:0,他引:3  
石鹏  徐凤燕  王宗欣 《信号处理》2005,21(5):502-504
基于对数正态分布的室内传播损耗模型,本文利用最大似然估计算法,通过迭代估计得到用户与各个接收机之间的距离和相应的传播损耗模型中的遮蔽因子,并由此估计得到室内用户的位置。仿真结果表明,本算法收敛速度快,并有较高估计精度。  相似文献   

14.
The radio-frequency identification (RFID) concept is expanded to millimeter-wave frequencies and millimeter-wave identification (MMID) in this paper. The MMID concept and a comparison with UHF RFID are presented, showing the limitations and benefits of MMID. Three feasible applications are suggested for MMID, which are: (1) wireless mass memory; (2) an automatic identification system with pointing functionality; and (3) transponder communication with automotive radar. To demonstrate the feasibility of the MMID system, experimental results for both downlink and backscattering-based uplink are presented at 60 GHz.  相似文献   

15.
Wireless Personal Communications - Indoor Wireless Local Area Network location estimation using received signal strength indication (RSSI) has gained importance due to its low cost and...  相似文献   

16.
随着5G到来,不论市场和网络都对室内定位技术有紧迫的需求。本文提出了一种基于pRRU设备的上行场强实现的室内用户定位方法,该方法可高效、精确识别室内局部弱覆盖区域,准确率达92.26%,进而实现了室内网络质量的提升。同时,该方法也可在5G网络中应用,向市场提供完整的位置信息服务,进而可向市场推广店铺客源分析、精准营销或室内导航等业务。  相似文献   

17.
A novel model of millimeter-wave (MMW) indoor radio channel is presented in this paper. The model is related the random properties of the MMW radio channel to the underlying geometry of the environment. The geometric simplicity of the MMW channel is allowed examining fundamental deterministic properties of the wave propagation behavior in environments of predefined randomness. The dimensions and properties of environments are described by various probability distributions. Stochastic influence on the radio channel is studied for the down-link of a wireless local area network at 60 GHz. Other related factors, such as amplitudes of path lengths, angles of departure, and amplitudes, as well as spatial power densities, average power of the direct paths are investigated.  相似文献   

18.
为了设计一套高精度、高实时性、操作简单的室内定位系统,该系统采用DW1000芯片设计制作了UWB定位硬件板;以node.js为基础,使用htm15、css3和js搭建了web界面;使用socket.io技术实现了前后端的双向实时通信。为了保证定位精度,采用双边双向测距方法来测量距离,用双曲线模型定位算法来解析定位结果。对整个定位平台进行了实验测试,测试结果表明该平台运行稳定,web界面能实时清晰地显示标签位置,并且标签的定点精度在10 cm左右,动点精度在20 cm左右。  相似文献   

19.
设计实现了一个独特的两级唤醒单元,该唤醒单元用于基于EPC C1G2空中接口协议的射频识别标签。该标签为半有源标签,在该单元支持下实现温度日志功能。设计经过SMIC0.18μm EE工艺流片验证。测试结果表明标签实现温度日志功能,在1.8V电源电压下消耗150nA的静态电流,在同类工作中处于优势地位。  相似文献   

20.
一款应用于GPS的CMOS低功耗高增益LNA   总被引:1,自引:1,他引:0  
针对当前应用于GPS射频前端的LNA存在的不足,设计了一种新型的LNA.从电路结构、噪声匹配、线性度、阻抗匹配、电压增益以及功耗等方面详细讨论了该低噪声放大器的设计.电路采用CMOS 0.18μm工艺实现,经过测试,低噪声放大器的增益为40.8dB,噪声系数为0.525dB,PldB为-29.5dBm,1.8V电压下的消耗电流仅为1.4mA.电路性能充分满足应用要求.  相似文献   

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