面向采煤机械在线状态监测系统设计

随着无线传感网络在人们日常生活中的应用越来越普及,传感网络节点的可持续工作能力问题日益突出。对无线传感网络节点的功耗问题进行分析,并设计出一种面向采煤机械的基于MSP430微控芯片的低功耗在线状态监测系统。根据低功耗在线状态监测系统采集机械设备所处环境中的振动和温度信息进行数据判断,进行异常报警。经过实验验证,该系统在数据传输、数据显示和功耗测试等方面都达到了设计要求。     

基于蓝牙4.0的低功耗无线传感器网络节点设计

针对国内外一些可穿戴式智能设备的无线传感节点的设计方案,有一些是基于集成了无线传输协议的控制器,他们有数字处理能力有限,硬件系统固定,缺乏单元灵活性,特别不利于多路参数并行处理的问题,设计了一种基于蓝牙4.0的低功耗无线传感器网络节点。使用了基于蓝牙4.0技术的CC2540芯片和Xilinx公司的低功耗FPGA芯片,并结合手机应用程序完成了系统设计。并且在硬件设计和软件设计上注意降低整个系统的功耗。测试结果表明,系统在低功耗设计的基础上,可以准确的将数据通过蓝牙发送出去。该系统具有低功耗、低成本、开发难度小等特点,可适用于可穿戴式智能设备等领域。     

基于RFID超低功耗射频标签的研究与实现

提出了一种基于2.4 GHz主动式非接触射频识别(RFID)标签结构,并设计了标签的硬件电路及软件.在主动式标签设计中,采用了MSP430F2122单片机和CYRF6936射频芯片的超低功耗方案.该标签具有识别距离远,稳定性高,超低功耗和抗干扰能力强等特点,因此,该标签适用于各种条件复杂的恶劣环境,如煤矿井下生产、石油开采现场等复杂环境.     

超低功耗粮仓无线实时监测系统设计

针对在粮库温度智能监测领域,采用电线电缆传输数据的不便以及目前无线传感网络节点寿命短的问题,利用MSP430超低功耗单片机设计了超低功耗无线温度监测系统。基于超低功耗设计了系统的整体框架以及各模块硬件,其中包括节点、温度传感器模块、无线通信模块、通信协议、桌面实时显示程序,通信协议解决了多个节点同时介入时的碰撞问题并设计了节能算法。最后对整个系统的可靠性以及节点的使用寿命进行了实验验证,经过试验的检验本系统具有超低功耗的特点,基本满足超低功耗粮仓无线实时监测系统的设计需求。     

低功耗蓝牙DA14585的无线传感器网络应用分析

本文以低功耗蓝牙芯片DA14585为研究对象,对其基础上的无线传感网络技术应用进行分析。通过对基本概念的简要描述,分析低耗蓝牙无线传感网络中的设计要点,并在具体传感技术条件上,对硬件配置、软件设计、路由协议这三方面内容进行分析,为低功耗蓝牙技术的物联网应用提供参考依据。     

基于ＬＯＲＡＴＭ调制的低功耗光功率检测标签设计

针对工业生产领域有线设备检测光功率的不便,从应用角度出发,提出一种基于LORA^TM调制的低功耗光功率检测标签设计。无线低功耗光功率检测标签由光传感器、低功耗处理器、LORA^TM调制解调器和锂电池组成,光传感器将光强转换为大小变化的电流,通过对电容充放电和单稳态触发器,产生频率变化的脉冲信号,低功耗处理器在固定时长窗口下检测脉冲个数从而获得光功率,并通过LORA^TM调制将数据发送至手持PAD进行数据展示。实验证明：本设计系统稳定,检测精度高,待机电流低至0.2mA。     

基于RFID传感和DBN的人体活动识别技术研究

本文提出一种基于RFID传感标签和深度信念网络（Deep belief networks, DBN）的人体活动识别技术。首先,设计了一种无源RFID（Radio frequency identification,RFID）传感标签,人体加速度信号存入传感器数据区,标签序列号和硬件版本组成了标签ID可以进行唯一标识。然后从数据中提取初始特征,采用核主成分分析（KPCA）和线性判别分析（LDA）对特征进行进一步处理,使其更具鲁棒性,有利于快速的人体活动识别。最后,利用这些特征训练DBN。在一个可穿戴传感器数据集上进行实验,仿真结果表明,所设计的传感标签最小灵敏度约为-17dBm,对应在2W的阅读器功率下传感标签最大工作距离为10.5m;所提出的DBN算法优于其他算法,也极大的提高了识别准确率。     

面向智能图像传感系统的感内计算技术发展趋势分析

物联网大数据时代,图像传感系统的端侧智能应用大规模部署,催生了传感器向智能化、高集成度和低功耗的趋势发展。感内计算技术利用像素层级的感算、感存算一体化功能,实现了二维空间感知信息的高精度、高并行模数混合运算。感内计算技术结合近感计算和感外计算技术的研究成果,将为面向端侧智能应用的新型图像传感系统提供一系列低成本、多元化解决方案。     

WirelessHART智能压力仪表的设计

采用超低功耗的PIC18 LF45 K22单片机作为主控制器,结合超低功率的WirelessHART射频收发器模块XDM2510 H以及独立的电量测量芯片DS2782等芯片模块,设计了一种运行可靠,具有全网电量管理和辅助诊断功能的低功耗智能压力仪表。介绍了无线HART标准及其在应用中的优势,并阐述了该压力仪表设计的总体结构,以及具体的硬件电路和软件实施方案,说明了该智能压力仪表的工作原理和特点。     

基于无线传感器网络的数据采集系统研究

设计一种新的基于无线传感网络的数据采集系统,其由电源模块、无线模块和控制模块组成。电源模块为无线模块和控制模块提供电能,无线模块使用智能总线协议或低功耗射频协议从传感器中采集数据,控制模块利用MSP430F4250微处理芯片控制无线模块的采集工作,并对所采集到的传感器数据进行处理,处理后的数据将传回无线模块,用户通过控制模块设置数据交互标准,对无线模块中处理后的传感器数据进行提取。实验结果表明,所设计的系统拥有极小的采集误差和极低的无线通信误码率,较好地实现了设计目标。     

A passive UHF RFID tag chip with a dual-resolution temperature sensor in a 0.18μm standard CMOS process

This paper presents a passive EPC Gen-2 UHF RFID tag chip with a dual-resolution temperature sensor. The chip tag integrates a temperature sensor,an RF/analog front-end circuit,an NVM memory and a digital baseband in a standard CMOS process.The sensor with a low power sigma-delta(ΣΔ) ADC is designed to operate in low and high resolution modes.It can not only achieve the target accuracy but also reduce the power consumption and the sensing time.A CMOS-only RF rectifier and a single-poly non-volatile memory(NVM) are designed to realize a low cost tag chip.The 192-bit-N VM tag chip with an area of 1 mm~2 is implemented in a 0.18-μm standard CMOS process.The sensitivity of the tag is -10.7 dBm/-8.4 dBm when the sensor is disabled/enabled.It achieves a maximum reading/sensing distance of 4 m/3.1 m at 2 W EIRP.The inaccuracy of the sensor is -0.6℃/0.5℃(-1.0℃/1.2℃) in the operating range from 5 to 15℃in high resolution mode(-30 to 50℃in low resolution mode).The resolution of the sensor achieves 0.02℃(0.18℃) in high(low) resolution mode.     

Functional antenna integrated with relative humidity sensor using synthesised polyimide for passive RFID sensing

A new type of antenna with an RH (relative humidity) sensing function using a modified polyimide is proposed for passive RFID sensing. Designed to operate at a frequency that depends on the relative humidity level, the proposed antenna is a passive device that physically and functionally combines an antenna with an RH sensor. The compactness and cost-efficiency of the antenna enables it to realise a passive tag of the RFID sensing without an additional sensor component     

应用于无源UHF RFID传感器接口的低功耗低压转换器设计

为了增加射频识别（RFID）传感器的识读范围,针对无源超高频（ultra high frequency,UHF）RFID标签的传感器接口,提出了一种新的低功耗低压时间数字转换器设计。该传感器接口采用基于游标原理的高效时数转换器,在保证分辨率和转换效率的同时,能够实现较低的功耗和较大的动态范围。采用TSMC 90nm标准CMOS技术设计并制造。测量结果显示相比其他类似结构,提出接口在输入时间范围28.18-42.94 时有效分辨率为10.48bits。采样率为20 KS/s时,转换器转化效率为0.396 pJ/bit,且功耗和电压供应分别仅为3.84 和0.6V,能够有效增强无源UHF RFID压力传感器标签的识读范围。     

Testing the effects of temperature and humidity on printed passive UHF RFID tags on paper substrate

This article is an interesting substrate material for environmental-friendly printable electronics. In this study, screen-printed RFID tags on paper substrate are examined. Their reliability was tested with low temperature, high temperature, slow temperature cycling, high temperature and high humidity and water dipping test. Environmental stresses affect the tag antenna impedance, losses and radiation characteristics due to their impact on the ink film and paper substrate. Low temperature, temperature cycling and high humidity did not have a radical effect on the measured parameters: threshold power, backscattered signal power or read range of the tags. However, the frequency response and the losses of the tags were slightly affected. Exposure to high temperature was found to even improve the tag performance due to the positive effect of high temperature on the ink film. The combined high humidity and high temperature had the most severe effect on the tag performance. The threshold power increased, backscattered power decreased and the read range was shortened. On the whole, the results showed that field use of these tags in high, low and changing temperature conditions and high humidity conditions is possible. Use of these tags in combined high-humidity and high-temperature conditions should be carefully considered.     

A battery-less BLE smart sensor for room occupancy tracking supplied by 2.45-GHz wireless power transfer

Wireless power transfer (WPT) has emerged as a solution for supplying smart sensors for long-term battery-less deployment. Because the amount of power harvested by the smart sensor is limited due to WPT path loss, the optimization objective is twofold: achieving ultra-low-power operation for the sensing task and improving the harvesting efficiency even at low incident power. In this paper, we focus on the use case of a Bluetooth LE-connected motion detection system supplied by 2.45-GHz RF power. The full system (RF energy harvester, power management, sensor transducer and interface, control, data processing and wireless transmission) is implemented using low-power off-the-shelf components. In the sensing sub-system, ultra-low-power operation is achieved by the duty-cycling of the sensor interface and by an event-driven scheme for communication. In the harvesting sub-system, the design of the matching network and rectifier, combined with maximum power point tracking (MPPT), is optimized for increasing the power harvesting efficiency (PHE) at low incident power. Measurements show a total reduction in the power consumption for the sensing sub-system by a factor 20. When using custom WPT waveform with high peak-to-average power ratio, the RF energy harvester is functional with an incident RF power starting from −20 dBm. The smart sensor is able to perform its motion-detection task with an incident power as low as −17.3 dBm.     

UHF RFID标签基带处理器的低功耗设计

随着超高频RFID标签的应用越来越广泛,在提高其性能上的需求也越来越迫切.对于无源标签,工作距离是一个非常重要的指标.要提高工作距离,就要降低标签的功耗.着重从降低功耗方面阐述了一款基于ISO18000-6 Type C协议的UHF RFID标签基带处理器的设计.简要介绍了设计的结构,详细阐述了各种低功耗设计技术,如动态控制时钟频率、寄存器复用、使用计数器和组合逻辑代替移位寄存器、异步计数器、门控时钟等的应用.结果证明,这些措施有效地降低了功耗,仿真结果为在工作电压为1 V,时钟为2.5 MHz时,功耗为4.8 μW;目前实现了前三项措施的流片,测试结果表明工作电压为1 V,时钟为2.5 MHz时,功耗为8.03 μW.     

智能滑套内低频段RFID 标签识别率的研究

实际应用中智能滑套内低频段RFID 标签存在识别率低的问题,从射频识别技术的工作机理出发,借助MATLAB 仿真软件,对低频螺线管天线感应电压特性进行了仿真分析,讨论了读写器天线长度和内径对识别率的影响,提出了基于井下智能滑套的RFID 通信系统最佳天线部署。同时为减弱井下复杂工况环境对标签识别率的影响,设计了读写器天线自适应阻抗匹配系统,建立一套基于井下RFID 通信系统识别率的模拟试验平台,验证仿真设计结果的正确性。     

适用于RFID标签及无线传感器的射频唤醒电路

有效的功耗管理是提升有源RFID标签以及无线传感器节点电池使用寿命的重要方法,一种无源射频唤醒电路可以用来控制标签以及传感器节点的工作状态,使之在外界无线电波控制下进行唤醒状态与休眠状态的切换,与传统周期性唤醒方法相比,该方法减少了大量能量损耗.围绕着提高射频唤醒电路灵敏度的指标,对阻抗匹配网络以及整流电路进行了优化.仿真和测试结果表明该电路在-27.7dBm输入功率下可以产生220mV直流输出.该唤醒电路本身无需耗电,实践表明将其应用在RFID标签及无线传感器节点设计中可显著提升电池使用寿命.     

便携式低功耗温度检测仪设计

便携式低功耗温度检测仪主要由一体化智能温度检测模块、nRF905无线数据收发模块和LCD温度数据显示模块构成。该检测仪具有体积小、易便携、低功耗等特点,能广泛应用于楼宇自动化建设过程中的温度数据采集、仓储房间的温湿度测量及控制等方面。     

Energy-efficient digital and wireless IC design for wireless smart sensing

Wireless smart sensing is now widely used in various applications such as health monitoring and structural monitoring. In conventional wireless sensor nodes, significant power is consumed in wirelessly transmitting the raw data. Smart sensing adds local intelligence to the sensor node and reduces the amount of wireless data transmission via on-node digital signal processing. While the total power consumption is reduced compared to conventional wireless sensing, the power consumption of the digital processing becomes as dominant as wireless data transmission. This paper reviews the state-of-the-art energy-efficient digital and wireless IC design techniques for reducing the power consumption of the wireless smart sensor node to prolong battery life and enable self-powered applications.