Design of a low-power CMOS transceiver for semi-passive wireless sensor network application

A 50 kbps/ISM band (902 − 926 MHz) low power transceiver for short-range wireless sensor networks (WSN) has been designed in 0.18 μm 1-poly-6 metal CMOS technology and occupy 950 μm × 800 μm. The proposed WSN transceiver designed based on an improved version of the Amplitude-Shift Keying communication scheme has a better continuous RF modulated carrier waveform as well as does not require complex modulator/demodulator circuits. In addition, to reduce power dissipation and increase power efficiency many circuit techniques have been adopted. The power dissipation and the power efficiency of the proposed WSN transceivers are 1.58 mW and 21%, respectively.     

一种电流复用共栅低噪声放大器的低功耗433/915-MHz射频前端的设计

This paper presents a wideband RF front-end with novel current-reuse wide band low noise amplifier(LNA),current-reuse V –I converter,active double balanced mixer and transimpedance amplifier for short range device(SRD) applications.With the proposed current-reuse LNA,the DC consumption of the front-end reduces considerably while maintaining sufficient performance needed by SRD devices.The RF front-end was fabricated in 0.18 μm RFCMOS process and occupies a silicon area of just 0.11 mm2.Operating in 433 MHz band,the measurement results show the RF front-end achieves a conversion gain of 29.7 dB,a double side band noise figure of 9.7 dB,an input referenced third intercept point of –24.9 dBm with only 1.44 mA power consumption from 1.8 V supply.Compared to other reported front-ends,it has an advantage in power consumption.     

A CMOS adaptive RF front-end receiver for wireless applications

The performance of signal-processing algorithms implemented in hardware depends on the efficiency of datapath, memory speed and address computation. Pattern of data access in signal-processing applications is complex and it is desirable to execute the innermost loop of a kernel in a single-clock cycle. This necessitates the generation of typically three addresses per clock: two addresses for data sample/coefficient and one for the storage of processed data. Most of the Reconfigurable Processors, designed for multimedia, focus on mapping the multimedia applications written in a high-level language directly on to the reconfigurable fabric, implying the use of same datapath resources for kernel processing and address generation. This results in inconsistent and non-optimal use of finite datapath resources. Presence of a set of dedicated, efficient Address Generator Units (AGUs) helps in better utilisation of the datapath elements by using them only for kernel operations; and will certainly enhance the performance. This article focuses on the design and application-specific integrated circuit implementation of address generators for complex addressing modes required by multimedia signal-processing kernels. A novel algorithm and hardware for AGU is developed for accessing data and coefficients in a bit-reversed order for fast Fourier transform kernel spanning over log?₂ N stages, AGUs for zig-zag-ordered data access for entropy coding after Discrete Cosine Transform (DCT), convolution kernels with stored/streaming data, accessing data for motion estimation using the block-matching technique and other conventional addressing modes. When mapped to hardware, they scale linearly in gate complexity with increase in the size.     

基于CC2430的ZigBee无线网络节点设计

ZigBee无线网络结构简单、设计成本低廉,功耗低,并拥有简单而灵活的通信网络协议,应用非常广泛。采用集射频与微控制器于一体的片上系统CC2430作为ZigBee无线网络节点的核心器件,提出带功率放大器的ZigBee无线网络节点的系统设计方案,并给出该系统电路原理图。硬件测试结果表明,节点硬件接收灵敏度高,通信距离也较理想。     

基于ZigBee技术的电源网络监控系统设计

随着日常生活和生产中设备对用电的要求,电源的管理越来越重要,电源的稳定性不仅影响设备的正常工作,还会带来相应的安全隐患.在系统设计中对电源要进行必要的监测和控制,电源监控系统中终端设备单独对电源模块进行监控,对电源的控制采用快速响应继电器来减少延迟,从而保证系统安全.本文提出了基于ZigBee无线传感网的电源监控系统软件设计和硬件设计方案.系统中的ZigBee无线模块节点采用CC2430芯片为核心,优点是成本低、协议简单和组网容易等.     

A 863-870-Mhz spread-spectrum direct conversion receiver design for wireless sensor

This paper presents simulation results of the receiver section of a frequency-hopped spread-spectrum transceiver operating in the 863–870 MHz European band for wireless sensor applications. The receiver is designed for binary frequency-shift keying (BFSK) modulation, communicating a maximum data rate of 20 kb/s. The receiver combines a low-noise amplifier with down conversion mixer, a low-pass channel-select filter and a limiter. The various block parameters of the receiver like noise figure, gain and IIP3 are simulated and optimized to meet receiver specifications. The receiver simulations show 51.1 dB conversion gain, -7 dBm IIP3, -15 dB return loss (S₁₁) and 10 dB NF.     

ZigBee无线传感网温度监测系统设计

介绍了无线传感网络的体系结构,提出了一种基于ZigBee技术的无线传感网温度检测系统的设计方法。该系统将采集到的温度数据通过数据采集节点和协调器节点及组成ZigBee网络传送给PC机,然后进行统一的分析和处理。该系统也可以应用于其他领域。     

基才ZigBee协议栈的无线传感器网络的设计

首先介绍了无线传感器网络的基本拓扑结构与传感器节点的结构,详细说明了基于ZigBee协议栈的无线传感网络的建立过程,包括协调器启动及建立网络、传感器节点启动及加入网络、传感器节点与协调器之间建立绑定以及传感器节点向协调器发送数据的过程。设计了基于ZigBee协议栈的无线传感网络系统。以采集温度信息为例,协调器能够接收到传感器节点发来的数据,并能通过RS232串口,将收到的数据发送给PC机进行显示。实验显示在距离80m远处,系统仍能保持良好的通信质量。     

ZigBee无线网络功放的设计与仿真

ZigBee是一种低速无线个域网技术,适用于通信数据量小,速度相对较低,并且功耗低的场合。组网灵活是其一大特点,但是由于传输距离比较短,从而限制了其发展。基于ZigBee无线通信网络技术,提出了一种通过增大发射信号功率、提高接收信号灵敏度来增加系统传输距离的方法。使用ADS软件主要对功率放大电路和低噪声放大电路进行仿真与性能优化,从而得出最佳设计方案。仿真结果基本满足了系统功率和增益的要求。     

基于ZigBee智慧实验室系统的设计*

首先对目前国内外室内物联网应用的现状进行了调查,分析了室内物联网技术在实验室建设和管理应用中的实用性和可行性.提出了智慧实验室的概念和智慧实验室系统的整体框架,整个系统由实验室资产管理子系统、实验室视频监控子系统、实验室网关和上位机系统4个模块组成.分别介绍了系统各个模块的功能,并对整个系统进行了设计.最后对所设计的系统进行了性能测试,测试结果表明该系统实现了对实验室管理的科学化、现代化及信息化,提升了实验室管理的智能化水平,对“智能家居”和“智慧城市”的发展建设有重要的借鉴意义和参考价值.     

一种应用于无线局域网的无源CMOS混频器

针对一种双平衡结构的无源CMOS混频器,分析了它的转换增益、噪声系数和线性等参数,在此基础上,推导了它的电路设计方程.设计了该混频器应用于2.4 GHz无线局域网(WLAN)的电路拓扑,并应用TSMC的0.18 μm CMOS工艺进行了仿真.结果显示,在1.8 V的工作电压下,该混频器具有非常出色的性能指标,转换增益最大为-1.2 dB,噪声系数为6.3 dB,1 dB压缩点为-4 dB,功耗小于1 mW.     

基于ZigBee无线网络的气体监测报警系统设计

利用ZigBee实现短距离无线传输数据的技术,提出一种基于ZigBee无线网络的气体监测报警系统。该系统包括终端节点、协调器、GSM模块、手机4部分,终端节点与协调器通过ZigBee无线网络进行通信,且对系统的硬件和软件设计进行了分析。当有毒气体浓度超过警戒值,则驱动蜂鸣器和LED指示灯进行声光报警。实践证明,利用ZigBee技术传输数据具有功耗低、时延小、体积小、耗资少等优点。     

基于无线自组网技术的监控系统设计

设计一套基于无线自组网技术的监控系统,旨在对运输及库存中的重要产品进行远距离监控,避免繁琐的人工管理过程。从通信组网、硬件设计方面介绍了初步方案设计,拟利用短距离、低耗的WSN实现相对静止空间内的组网,利用MANET实现相对运动时的组网,以实现全国范围内的,信息传递时间小于5分钟的动态监控网络。     

基于ZigBee的无线传感器网络网关的设计与实现

文中给出了基于ZigBee技术的无线传感器网络网关的设计方案。网关节点以微芯公司的PIC24FJ128GA010单片机为MCU,射频芯片为MRF24J40MA,采用串口转以太网模块达到协议转换的目的。软件方面采用微芯的开源ZigBee协议栈。     

基于ZigBee的无线数据采集系统的设计

以C8051F020和射频芯片CC2430为核心设计了低功耗的无线数据采集系统,介绍了ZigBee技术,并给出了基于ZigBee的无线数据采集系统的组成.最后通过使用CC2430芯片完成了采集节点,主控单元的硬件与软件设计,实现了数据的采集和无线传输.     

基于ZigBee技术的温湿度数据采集系统设计

随着嵌入式计算、传感器、无线通信等技术的飞速发展,无线传感网被广泛应用于环境监测、军事国防和工农业控制等诸多领域,已成为电子信息技术发展的一个热点。CC2430是TI公司针对ZigBee的无线传感网芯片解决方案,具有功耗低,可靠性高,组网简单等优势。基于CC2430和ZigBee协议,设计了温湿度数据采集系统,分别给出了协调器和普通节点的软件算法,在干扰环境下测试表明,网络具有较强的鲁棒性和自组能力。     

Hardware compression scheme based on low complexity arithmetic encoding for low power image transmission over WSNs

Software implementation costs of most algorithms, designed for image compression in wireless sensor networks, do not justify their use to reduce the energy consumption and delay transmission of images. Even though the hardware solution looks to be very attractive for this problem, a specific care should be paid when designing a low power algorithm for image compression and transmission over these systems. The aim of this paper is to present and evaluate a hardware implementation for user-driven image compression scheme designed to respect the energy constraints of image transmission over wireless sensor networks (WSNs). The proposed encoder will be considered as a co-processor for tasks related with image compression and data packetization. In this paper, we discuss both of the hardware architecture and the features of this encoder circuit when prototyped on FPGA (field-programmable gate array) and ASIC (application-specific integrated circuit) circuits.     

An adaptive joining mechanism for improving the connection ratio of ZigBee wireless sensor networks

Wireless sensor networks (WSNs) are well suited to many applications, including environment surveillance and target tracking. ZigBee is an IEEE 802.15.4‐based standard that is considered suitable for WSNs. The functional operations of a ZigBee network rely on self‐organized network connections and the proper deployment of sensor devices. However, the devices comprising a ZigBee network may become isolated from the network after the joining phase due to the configuration constraints of the ZigBee standard. This means that some deployed devices cannot join the network even though they can communicate with other joined nodes. These isolated devices reduce the efficiency of network operation and increase deployment costs. This paper proposes a ZigBee‐compatible adaptive joining mechanism with connection shifting schemes to improve the connectivity of ZigBee networks, allowing them to operate at the expected efficiency. Simulation results show that the proposed mechanism significantly improves the join ratio of deployed sensor devices in ZigBee WSNs. Copyright © 2009 John Wiley & Sons, Ltd.     

基于ZigBee协议的无线传感器网络服务质量的研究

针对于无线传感器网络的发展,以及新型的协议规范ZigBee协议在无线传感器网络中广泛应用,以分析研究基于ZigBee协议的无线传感器网络的服务质量的评价机制为目的。通过对无线传感器网络及ZigBee协议的组成、通信特点的研究,以及结合传统网络的QoS评价机制,最终总结得到可以从5个方面来评价ZigBee协议的无线传感器网络的服务质量。     

基于ZigBee的远程电力抄表数据采集器设计

为设计一种安装维护方便,低功耗和数据通信可靠的数据采集终端,根据无线技术发展,提出一种基于无线传感器网络的远程电力数据采集器设计方案,AVR作为整个系统的核心控制器,负责对采集的电量数据进行处理,并进行智能控制,利用ZigBee短距离无线通信技术进行数据传输,大大减少了工程的布线复杂度,提高了数据通信的可靠性,降低了功耗。试验结果表明,终端工作可靠、正常。