低功耗射频触发唤醒电路设计

为解决目前有源RFID标签的能耗问题,提出了基于射频触发唤醒技术(Radio wake-up)的低功耗解决方案。在传统有源RFID标签的基础上增加射频唤醒电路,阅读器首先发送一个唤醒信号,将附近的标签从休眠状态唤醒,然后进行数据通信。这使得有源标签大部分时间均处于低功耗的休眠状态,该方式可大幅减少射频通信模块的功耗,延长有源标签的寿命。仿真结果表明,该电路在-45.2 dBm输入功率下可唤醒标签,唤醒距离为30 m,且唤醒电路的功耗仅为4.11 μW(3 V,1.37 μA),能够满足大部分应用需求。     

Imagination发布超低功耗RPU架构

Imagination日前宣布发布新款Ensigrna Series4低功耗无线电处理器（RPU）架构“Whisper”，这是专为新一代要求超低功耗与低成本的可穿戴设备、物联网（IoT）所设计，特别聚焦于降低功耗、成本，提升灵活性。     

NB-IoT应用展望及生态协同

一直以来远距离无线接入网络的物联网终端在成本和功耗方面距离大规模应用需求依然差距较大,而大部分物联网终端接入网络是基于Wi-Fi或者蓝牙等短距离或低功耗技术,应用场景也受限于物联网终端的成本和功耗等,使得电信运营商很难从中获利. NB-IoT系基于蜂窝网络的窄带物联网通信技术,具备广域传输、海量介入、超低功耗、低成本等特征,NB-IoT技术与应用将进一步加速物联网发展的进程.目前接入运营商网络的物联网终端占比不足6％,电信运营商期望借助于NB-IoT来实现海量物联网终端的接入,驱动蜂窝物联网应用的商业“蓝海”,各界也都对NB-IoT技术与应用充满了热切期待.     

近阈值低功耗8位微处理器的设计与实现

随着RFID、可穿戴设备和物联网等应用的兴起,低吞吐率、功耗和能耗敏感的芯片设计开始受到广泛的关注,基于阈值电压的低功耗电路设计成为新的发展方向。文中基于SMIC0.13μm1P6M混合信号工艺,通过设计面向近阈值电压的标准逻辑库,在采用标准Top-Down设计流程的基础上,完成了一款近阈值低功耗8位微处理器的设计。封装后芯片的测试结果表明,该微处理器的最低工作电压可达0.2V,工作频率1k Hz~25MHz。与基于传统逻辑库的微处理器比,在20MHz的工作频率下,功耗降低了36%。     

产品汇总

正国内首款低功耗FPGA芯片CME-HR(黄河)系列前不久,京微雅格推出了其CME-HR(黄河)系列FPGA产品,可以满足低功耗、小封装及灵活的应用场景的需求。传统的FPGA主要用于产品开发的前期验证,而CME-HR(黄河)系列FPGA实现了极低的成本和功耗,可直接量产投入市场,在消费电子、物联网及可穿戴设备里,     

一种有线数字电视机顶盒远程唤醒实现方法

基于数字电视尤其是有线数字电视进行应急广播的相关技术获得很大进展,其技术实现模式和系统也日益受到相关科研和应用部门的重视,但目前大多数电视机顶盒日常待机时调谐器和解调解码等模块都处于待机甚至断电状态,无法响应前端系统发出的远程唤醒信号,从而无法启动应急广播相关流程。为此,提出了一种低成本低功耗的有线数字电视机顶盒的远程二次唤醒实现方法,很好地解决了作为应急广播终端的电视机顶盒远程唤醒和启动的问题。     

一种低功耗低噪声自偏置锁相环电路

在飞速发展的物联网、可穿戴设备、医疗电子等小型化领域,小尺寸、低功耗是集成电路设计的重要指标。本文提出了一种低功耗、面积小、低相位抖动的锁相环电路。利用自偏置技术补偿锁相环的环路增益等参数,同时简化压控振荡器和电荷泵的电路结构,取得了面积、功耗、噪声以及环路稳定性的良好统一。该锁相环电路作为独立IP模块实现在SMIC 40nm工艺上,供电电压为2.5V/1.1V,最高输出频率至2.5GHz以上,总功耗为4.2mW,面积仅为0.02 mm2 (180um*110um)。     

可唤醒的无线传感器网络的雨量节点的设计

通过软硬件结合的方式,实现以MSP430作为主芯片的可唤醒的无线传感器网络的雨量节点。设计以低功耗为前提,主要由MSP430F149、AT86RF212、ATA5282以及SL3型翻斗雨量传感器处理电路组成,利用DXP2004软件设计制作PCB板。传感器节点采用低频可唤醒芯片ATA5282地接收来自汇聚节点的低频唤醒信号,接收到正确信号时采集雨量数据并打包发送回汇聚节点。实验结果证明该雨量节点传输距离远、功耗低并且丢包率低。     

低功耗和小型化半导体器件掘金可穿戴设备市场

正02[技术篇]毫无疑问,前景可期的可穿戴设备将会为上游的半导体器件供应商带来巨大的市场,而可穿戴设备的小型化、低功耗和高性能的特征,给处于产业链上游的半导体供应商的技术进步提出了更高的要求。从构成可穿戴设备的电子控制硬件来看,大体可以分为处理器、传感器、存储、无线技术、电源管理、信号链、显示器件等重要组成部分,其中处理器、无线技     

一种低成本低功耗的有线数字电视机顶盒远程唤醒实现方法

【摘要】基于数字电视尤其是有线数字电视进行应急广播的相关技术获得很大进展,其技术实现模式和系统也日益受到相关科研和应用部门的重视,但目前大多数电视机顶盒日常待机时调谐器和解调解码等模块都处于待机甚至断电状态,无法响应前端系统发出的远程唤醒信号,从而无法启动应急广播相关流程,提出了一种低成本低功耗的有线数字电视机顶盒的远程二次唤醒实现方法,很好的解决了作为应急广播终端的电视机顶盒远程唤醒和启动的问题。     

Reducing false wake-up in contention-based wake-up control of wireless LANs

This paper studies the potential problem and performance when tightly integrating a low power wake-up radio (WuR) and a power-hungry wireless LAN (WLAN) module for energy efficient channel access. In this model, a WuR monitors the channel, performs carrier sense, and activates its co-located WLAN module when the channel becomes ready for transmission. Different from previous methods, the node that will be activated is not decided in advance, but decided by distributed contention. Because of the wake-up latency of WLAN modules, multiple nodes may be falsely activated, except the node that will actually transmit. This is called a false wake-up problem and it is solved from three aspects in this work: (i) resetting backoff counter of each node in a way as if it is frozen in a wake-up period, (ii) reducing false wake-up time by immediately putting a WLAN module into sleep once a false wake-up is inferred, and (iii) reducing false wake-up probability by adjusting contention window. Analysis shows that false wake-ups, instead of collisions, become the dominant energy overhead. Extensive simulations confirm that the proposed method (WuR-ESOC) effectively reduces energy overhead, by up to 60% compared with state-of-the-arts, achieving a better tradeoff between throughput and energy consumption.

     

Passive wake-up radios: From devices to applications

Energy efficiency is one of the most important criteria in the design of a wireless sensor network. Sensor nodes are usually battery-powered and thus have very limited lifetime. In this paper, we introduce a novel passive wake-up radio device named WISP-Mote that uses a passive RFID tag as a wake-up receiver for a traditional sensor node. We characterize the WISP-Mote with field tests in different operating environments and present the wake-up probabilities based on the distance between the wake-up transmitter and receiver. We then perform simulations to compare the performance of a network with WISP-Motes and with duty-cycling of the sensor nodes, using the wake-up probabilities measured in our field tests. Additionally, potential applications that can benefit from WISP-Motes are discussed, and the advantages of using WISP-Motes are identified by simulation results based on these application scenarios. Results show that the wake-up radio sensor networks have great potential over duty-cycling approaches for energy efficiency, while providing similar latency and packet delivery performances.     

基于低频唤醒技术的半主动式电子标签设计

文中介绍了半主动式电子标签硬件和软件的设计方案,应用AS3933低频唤醒接收芯片实现了电子标签低频唤醒接收功能。针对低频唤醒接收模块,计算和讨论了其并联谐振电路相关的参数,并给出了电路和程序设计的方案。应用低频唤醒技术的半主动式电子标签可靠的低频通信距离可达3m以上,同时低频唤醒技术显著降低了电子标签的运行功耗。     

A wake-up call for the engineering and biomedical science communities

With the burst of Information Technology (IT) bubble at the beginning of this century, people are looking for the next wave of technology in which to invest. While we believe that biomedical applications and systems are this next stage, unfortunately, the engineering and bioscience communities are unprepared for the many challenges. In order to connect the engineering and the biomedical science communities, we established the LifeScience Systems and Applications (LiSSA) Technical Committee within IEEE Circuits and Systems Society in 2005--an initiative supported by the National Institutes of Health (NIH) through a conference grant to enable dialogue between the engineering and biomedical science communities. Henceforth, we have organized several annual workshops with different themes on the NIH campus. After each workshop, a white paper is published in IEEE circuits and systems magazine to present the major challenges in various chosen theme areas. Recently, we chose "Biomarker Development and Applications" as our workshop theme. For the first time, we invited eight IEEE societies and various NIH institutes to send their representatives for face-to-face dialogue. This article presents the major challenges in biomarker development and applications based on the general consensus of the conference. The aim of the article is to serve as a wake-up call for more engineers to participate in crucial life-science application and systems research.     

A fully integrated CMOS super-regenerative wake-up receiver for EEG applications

A fully integrated super-regenerative wake-up receiver for wireless body area network applications is presented. The super-regeneration receiver is designed to receive OOK-modulated data from the base station. A low power waveform generator is adopted both to provide a quench signal for VCO and to provide a clock signal for the digital module. The receiver is manufactured in 0.18 μm CMOS process and the active area is 0.67 mm². It achieves a sensitivity of -80 dBm for 10^-3 BER with a data rate of 200 kbps. The power consumption of the super-regenerative wake-up receiver is about 2.16 mW.     

Idle-time energy savings through wake-up modes in underwater acoustic networks

Interest in underwater sensor networks has increased recently due to the possibility of using autonomous underwater vehicles and sensors to explore the oceans and monitor underwater equipment. Such networks, due to the need for long term deployments, must be energy efficient, like their terrestrial counterparts. However, there are fundamental differences between radio interfaces and acoustic modems, both in terms of achievable performance (e.g. bit rate and latency) and in terms of energy consumption (i.e. transmit power, receive power, sleep power, etc.). These differences may cause techniques that are highly effective for radios to perform poorly in acoustic scenarios. This paper considers asynchronous idle-time power management techniques and the effects of acoustic modem properties on the optimal solutions. Specifically, we compare two main techniques, a sleep cycling solution and a wakeup mode solution. We show that for traffic rates of greater than one packet every few hours, using a wakeup mode may be the most efficient way to save energy.     

Low-power wake-up receiver with subthreshold CMOS circuits for wireless sensor networks

We developed a wake-up receiver comprised of subthreshold CMOS circuits. The proposed receiver includes an envelope detector, a high-gain baseband amplifier, a clock and data recovery (CDR) circuit, and a wake-up signal recognition circuit. The drain nonlinearity in the subthreshold region effectively detects the baseband signal with a microwave carrier. The offset cancellation method with a biasing circuit operated by the subthreshold produces a high gain of more than 100 dB for the baseband amplifier. A pulse-width modulation (PWM) CDR drastically reduces the power consumption of the receiver. A 2.4-GHz detector, a high-gain amplifier and a PWM clock recovery circuit were designed and fabricated with 0.18-μm CMOS process with one poly and six metal layers. The fabricated detector and high-gain amplifier achieved a sensitivity of ?47.2 dBm while consuming only 6.8 μW from a 1.5 V supply. The fabricated clock recovery circuit operated successfully up to 500 kbps.     

Ground bouncing noise reduction technique considering wake-up delay in MTCMOS circuits

Multi-Threshold CMOS (MTCMOS) is an effective technique for controlling leakage power with low delay overhead. However the large magnitude of ground bouncing noise induced by the sleep to active mode transition may cause signal integrity problem in MTCMOS circuits. We propose a methodology for reducing ground bouncing noise under the wake-up delay constraint. An improved two-stage parallel power gating structure that can suppress the ground bouncing noise through turn on sets of sleep transistors consecutively is proposed. The size of each sleep transistor is optimized by a novel sizing algorithm based on a simple discharging model. Simulation results show that the proposed techniques achieve at least 23% improvement in the product of the peak amplitude of ground bouncing noise and the wake-up time when compared with other existing techniques.     

Distributed wake-up scheduling for data collection in tree-based wireless sensor networks

In a multi-hop wireless network, a conventional way of defining interference neighbors is to prohibit a node from using the same slot/code as those of its 1-hop and 2-hop neighbors. However, for data collection in a wireless sensor network, since the set of communication nodes is limited and the transmission directions are toward the sink, we show that a less strict set of interference neighbors can be defined. Based on this observation, we develop an efficient distributed wake-up scheduling scheme for data collection in a sensor network that achieves both energy conservation and low reporting latency.     

An efficient NBTI-aware wake-up strategy: Concept,design, and manipulation

High leakage power consumption has become a serious problem in modern IC designs. By isolating a circuit block that is not in use from the power supply, power gating has become one of the most effective ways to reduce leakage power. During the circuit wake-up process, turning on sleep transistors simultaneously may induce an excessive surge current, which will threaten signal integrity. To avoid significant surge currents, sleep transistor wake-up sequences should be carefully designed. On the other hand, PMOS sleep transistors may suffer from the Negative-Bias Temperature Instability (NBTI) effect, where the wake-up time is increased after circuit aging. Conventional fixed wake-up sequence-based methods do not consider the NBTI effect, which may result in a longer or an unacceptable wake-up time after circuit aging. Therefore, in this paper, we propose a novel reconfigurable circuit structure that can reconfigure the wake-up sequence and a novel NBTI-aware wake-up strategy to reduce the wake-up time. Our strategy first finds a set of proper wake-up sequences under different aging circumstances and then dynamically reconfigures wake-up sequences at runtime based on an actual aging scenario (i.e. different months or years of aging). The experimental results show that compared with a traditional fixed wake-up sequence approach, our strategy can reduce up to 49.78% of the average wake-up time latency. In the meantime, according to our estimation, to implement the reconfigurable wake-up sequence structure, the parasitic area overhead is only about 0.27% with a larger benchmark.