钟控准静态能量回收逻辑电路

钟控准静态能量回收逻辑(clocked quasi-static energy recovery logic,CQSERL)只在输入信号导致输出状态发生变化的情况下才对电路节点充电(或者回收),不需要在每个功率时钟周期循环充电和回收操作;CQSERL是单端输入输出逻辑,减小了电路实现代价.设计了4位QSERL串行进位加法器(RCA)电路,和相应的CMOS电路进行了功耗比较.功率时钟为10MHz时,CQSERL电路功耗是对应CMOS电路的35%.流片实现了一个简单结构的正弦功率时钟产生电路,功率时钟的频率和相位与外接系统时钟相同.     

钟控准静态能量回收逻辑电路

钟控准静态能量回收逻辑 (clocked quasi- static energy recovery logic,CQSERL)只在输入信号导致输出状态发生变化的情况下才对电路节点充电 (或者回收 ) ,不需要在每个功率时钟周期循环充电和回收操作 ;CQSERL是单端输入输出逻辑 ,减小了电路实现代价 .设计了 4位 QSERL 串行进位加法器 (RCA)电路 ,和相应的 CMOS电路进行了功耗比较 .功率时钟为 10 MHz时 ,CQSERL 电路功耗是对应 CMOS电路的 35 % .流片实现了一个简单结构的正弦功率时钟产生电路 ,功率时钟的频率和相位与外接系统时钟相同     

利用环境电磁波为无线传感器节点供电新方案

采用无线传感器节点的环境电磁波能量获取关键技术,设计了一种可行的供电方案.通过对所处环境的频谱能量分析和采用合适的天线及转换电路,收集到足够能量驱动节点工作.同时设计了带有唤醒机制的低功耗电源管理电路,以适应节点在环境电磁波能量较少地区的工作.通过获取能量稳定性、有效工作范围和传感器节点的性能相关测试和分析,验证了方案...     

一种新型差分脉宽控制环路的设计

设计了一种新型时钟稳定电路～差分脉宽控制电路.用参考电路产生参考电压,避免因采用环形振荡器等方法产生大的时钟抖动.同时,在控制电路部分用交叉耦合正反馈来调节时钟占空比.该电路采用0.18 μm工艺,电源电压为1.9 V,输入时钟占空比调节范围为25%～75%,时钟频率为2 GHz,时钟抖动小于200 fs.     

一种DSP内嵌DARAM的电路设计与ADvanceMS仿真验证

介绍了一种DSP芯片内嵌DARAM的电路结构,详细分析了接口电路中各个模块的功能,包括地址译码电路,字线译码电路,位线选择电路及控制电路四部分内容。着重介绍了控制电路的原理,及如何实现一个周期"双存取"的功能。利用数模混合仿真工具ADvance MS对整体电路进行仿真,结果证明DARAM可以在一个时钟周期内完成一次读和一次写操作,实现预期的功能,为DSP设计乃至SOC的设计工作提供了参考。     

基于安全性的无线传感器网络时钟同步算法研究

无线传感器网络存储能力不高,导致以往提出的无线传感器网络时钟同步算法的安全性能不高、同步误差较大,现提出基于安全性的无线传感器网络时钟同步算法。基于安全性的无线传感器网络时钟同步系统中的父节点构建无线传感器网络和子节点,子节点通过与父节点进行数据交互,平衡无线传感器网络时钟同步,CC2530芯片将父节点和子节点进行连接。无线传感器网络时钟同步的运算工作在仿真器中完成,传输接口将父节点和子节点的交互信息输出到仿真器,为运算工作提供数据仿真源。安全性调试接口对父节点构建网络结果和时钟同步运算结果进行实时展示。系统对同步安全算法和同步算法语言的设计,较为有效地实现了无线传感器网络时钟同步。经实验验证可知,所提算法同步误差小,安全性能高。     

应用于热电能量收集的低压自启动电路

设计了一种两级低电压自启动电路,实现低输入电压条件下热电能量收集系统的自启动。在第一级自启动电路中引入一种新型堆叠式反相器,构成环形振荡器结构,在低供电电压下产生较大的振荡摆幅;第二级自启动电路由高幅值时钟产生电路与电感复用升压电路构成,进一步提高输出电压;由电压检测电路以及辅助电路构成的控制电路实现了第一级自启动向第二级自启动的转换,以及第二级自启动向主升压转换的过程。基于0.18 μm CMOS工艺设计该自启动电路,版图后仿真结果表明,在190 mV的TEG输入电压,以及11.8 μA的负载电流情况下,自启动电路可产生825 mV输出电压,转换效率可达到56.5%,实现能量收集系统的自启动功能,保证后级主升压电路的正常工作。     

网络入侵后最优节点通信组网选择技术的研究

网络在受到病毒入侵后,需要进行路由节点的优化通信组网选择,保障网络通信的稳定性和鲁棒性。提出一种基于VMEBus总线轮换调度控制的网络入侵后最优节点通信组网选择技术,结合嵌入式控制技术,进行网络入侵后的节点通信组网选择控制系统的优化设计。通过串口、VXI总线、CAN总线构建人机通信模块,采用时钟同步技术进行通信节点组网的程控控制和自适应组网调控,对环形RAM缓冲区内的恶意节点进行层次化网格调度。系统的硬件模块设计中重点对A/D采样滤波电路、复位电路、时钟触发电路、中央控制电路和外围接口电路等进行设计描述。在嵌入式平台上进行系统的软件开发,实现了网络入侵后最优节点通信组网选择优化控制。仿真结果表明,该系统进行节点通信组网优化部署控制,能提高对网络入侵的抗干扰能力,降低了节点进行网络数据传输的误码率,保障了网络安全。     

能量回收技术在D触发器上的应用

将能量回收技术应用于灵敏放大器型D触发器(SAERD),该电路采用单相正弦时钟,用来回收时钟端的能量,对于触发器的内部节点和存储单元仍采用恒定电源。在时钟频率为100～300MHz时,时钟端的功耗较输入方波时平均节省约80%。在SMIC0.13μm工艺下将SAERD应用于一款函数发生器,并与传统主从型D触发器(MSD)实现的电路进行功耗比较。仿真结果显示,时钟频率为200MHz时,功耗节省高达17.1%。     

基于FPGA的超声相控阵发射电路研究

针对基于现场可编程逻辑门阵列(Field Programmable Gate Array,FPGA)的高精度相控阵控制电路,采用锁相环技术的延时控制电路设计方法,在Modelsim软件中设计、仿真相控阵发射电路的聚焦和延时功能。在设计过程中,采用S扫描的扫描方式,由相控阵发射原理计算出相控阵发射电路的延时时间,通过相应的延时得到相控阵发射电路的聚焦。采用FPGA内部集成的锁相环,可以对输入时钟进行倍频或者分频,以此产生超声相控阵发射电路所需要的相关时钟信号。     

A new algorithm for cluster head selection in LEACH protocol for wireless sensor networks

In wireless sensor network, a large number of sensor nodes are distributed to cover a certain area. Sensor node is little in size with restricted processing power, memory, and limited battery life. Because of restricted battery power, wireless sensor network needs to broaden the system lifetime by reducing the energy consumption. A clustering‐based protocols adapt the use of energy by giving a balance to all nodes to become a cluster head. In this paper, we concentrate on a recent hierarchical routing protocols, which are depending on LEACH protocol to enhance its performance and increase the lifetime of wireless sensor network. So our enhanced protocol called Node Ranked–LEACH is proposed. Our proposed protocol improves the total network lifetime based on node rank algorithm. Node rank algorithm depends on both path cost and number of links between nodes to select the cluster head of each cluster. This enhancement reflects the real weight of specific node to success and can be represented as a cluster head. The proposed algorithm overcomes the random process selection, which leads to unexpected fail for some cluster heads in other LEACH versions, and it gives a good performance in the network lifetime and energy consumption comparing with previous version of LEACH protocols.     

Cooperative and Reliable ARQ Protocols for Energy Harvesting Wireless Sensor Nodes

One class of wireless sensor networks makes use of sensor nodes that recharge their batteries by harvesting energy from the surrounding environment. Being continuously recharged, the battery does not need to be replaced regularly and the sensor node is maintenance-free. A key module in such sensor network solutions is the data link automatic repeat request (ARQ) protocol, which must be designed to reliably deliver sensor nodes data at the minimum energy cost. With this objective in mind, two ARQ protocol classes are compared. In one class, each sensor node operates individually. In the other, the concept of cooperative communications is adopted, whereby neighboring sensor nodes help each other during the retransmission process. It is shown that the use of cooperative ARQ protocols in energy harvesting sensor networks enables sensor nodes to balance their energy consumption to match their own battery recharge rate. In turn, a balanced energy consumption-to-recharge rate ratio has the potential to improve the network throughput. Both classes of ARQ protocols are analyzed and compared. Estimated throughput gains are discussed under various network scenarios.     

Energy usage analysis of digital modulations in wireless sensor networks with realistic battery model

A wireless sensor network is a collection of tiny sensor nodes that are deployed to monitor a physical environment. These sensor nodes are generally powered by non-renewable batteries and maybe deployed in harsh environment. Thus, energy resource is precious that makes protocols design for this kind of networks a crucial challenge. Especially, in physical layer, orthogonal modulations as PPM or FSK are suitable. The commonly used models to investigate the network lifetime are based on a linear battery discharge. Really, the battery discharge is closely bonded to the discharge current, and typically is non-linear. This paper presents a performance analysis of both PPM and FSK modulations used in battery powered wireless sensor node. A Rakhmatov–Vrudhula–Wallach model is used to evaluate the used battery charge for a given instantaneous current load. By numerical results, it is proved that PPM modulation outperforms FSK one in term of battery charge use for different network density and for different M-ary signaling schemes.     

Increasing network lifetime by balancing node energy consumption in heterogeneous sensor networks

Sensor nodes are powered by battery and have severe energy constraints. The typical many‐to‐one traffic pattern causes uneven energy consumption among sensor nodes, that is, sensor nodes near the base station or a cluster head have much heavier traffic burden and run out of power much faster than other nodes. The uneven node energy dissipation dramatically reduces sensor network lifetime. In a previous work, we presented the chessboard clustering scheme to increase network lifetime by balancing node energy consumption. To achieve good performance and scalability, we propose to form a heterogeneous sensor network by deploying a few powerful high‐end sensors in addition to a large number of low‐end sensors. In this paper, we design an efficient routing protocol based on the chessboard clustering scheme, and we compute the minimum node density for satisfying a given lifetime constraint. Simulation experiments show that the chessboard clustering‐based routing protocol balances node energy consumption very well and dramatically increases network lifetime, and it performs much better than two other clustering‐based schemes. Copyright © 2006 John Wiley & Sons, Ltd.     

基于传输距离和Sink移动的扩延网络寿命算法

在无线传感网络WSN(Wireless Sensor Network)中,传感节点通常以多跳方式向信宿Sink传输感测数据.由于邻近信宿Sink的传感节点需要承担数据转发的任务,比其他节点消耗更多的能量,缩短了网络寿命.为此,提出一种扩延网络寿命的新算法,记为NLTA(Network LifeTime Augmentation).NLTA算法采用了节点传输距离自适应调整和信宿Sink移动两个策略.节点依据能量情况,调整传输距离,减少能量消耗,然后根据路径容量值,调整Sink的位置,平衡网内的节点能量消耗,避免信宿Sink的周围节点能量过度消耗.仿真结果表明,提出的NLTA方案能够有效地提高网络寿命.     

无线网络节点的微能源电源设计

无线传感器网络(WSNs)是无线网络的多种表现形式之一。面对目前的无线网络节点的续航难问题,本设计提出了一种利用微能源为无线传感网络节点提供供电的研究方案。本文采用压电陶瓷片作为能量的主要来源,选择采用专业的压电能量采集芯片LTC-3588进行构建电源电路,设计了无线网络节点终端。     

一种适用于无线传感器网络的 高效节能广播机制

 针对无线传感器网络结点体积小、内存与计算能力小、靠电池供电、结点密度高以及网络规模大的特点,提出了高效广播协议(EBP,Effective Broadcast Protocol).通过对广播过程中一个结点转播之后其邻域内其它结点的转播,即引发新转播的讨论,完成了对最佳引发新转播的分析.EBP广播协议以此为依据选择转播结点,不需要任何邻结点信息就可以高效完成广播,算法的控制开销和存储开销大大降低.EBP广播机制简单有效,在无线传感器网络中具有良好的扩展性.     

An Analysis of Energy Efficiency Improvement Through Wireless Energy Transfer in Wireless Sensor Network

In a wireless sensor network, wireless Energy transfer is a demanding technology for the energy difficulties in recent times. The foremost disadvantage of presentation is limited duration because WSN contains only restricted battery energy at a node. Therefore, we anticipated cluster-related wireless energy transfer in this document. The foremost intention of the method is to augment the duration of the sensor network through charging by the help of this wireless power transfer technology. So that, mobile charging vehicle (MCV) is established to move within the network and charge the sensor node battery wireless. The sensor nodes in the network are collected as a cluster for energy efficiency. Here, the cluster head is chosen for each one cluster in the network which is based on the rank metric value. Suppose, if one node in the network is reducing its energy, then the CH will send charge request and route ID to the MCV. Afterward, the MCV recognize the node by means of the exacting route and establish to charge the node. The reproduction consequences illustrate that the network lifetime of our anticipated method is enhanced than obtainable method.

     

LEACH协议中的最佳建簇概率

无线传感器网络中,传感器节点是通过携带能量有限的电池供电,因此如何有效利用能量,延长节点的生命周期是无线传感器网络首要研究的问题。为了达到降低网络能源消耗的目的,本文在第一顺序无线电模型的基础上利用能量消耗的关系得到了典型分簇路由协议LEACH的最佳建簇概率。研究结果表明,当分簇数目小于最佳建簇数目时,传感器网络每轮消耗的总能量就会以指数方式增加,说明确立最佳建簇数目可以降低网络能耗,从而提高无线传感器网络的整体生存时间。 更多还原     

ROTEE: Remora Optimization and Tunicate swarm algorithm-based Energy-Efficient cluster-based routing for EH-enabled heterogeneous WSNs

Since the development of Wireless Sensor Networks (WSNs), the limited battery of the sensor nodes has been an unavoidable concern. Hence, to keep the WSNs operational for a longer possible duration, the recharging of node's battery through harvesting the ambient energy from surroundings (for an example, solar energy) has been proposed. In this work, we focus not only on utilizing the energy harvesting (EH)-enabled sensor nodes for routing purposes but also introduce a novel hybrid optimization ROATSA that uses Remora Optimization Algorithm (ROA) and Tunicate Swarm Algorithm (TSA) for energy-efficient cluster-based routing. The proposed work is termed as ROA and TSA-based Energy-Efficient Cluster-based Routing for EH-enabled WSN (ROTEE). Hybrid ROATSA is chosen due to enhanced convergence and exploitation capabilities. To reduce the financial burden on the network, we use only four EH-enabled nodes and locate them at each periphery of the network, equidistant to each other and the other nodes are 3-level energy heterogeneous sensor nodes. The selection of cluster head (CH) is optimized through ROATSA by considering profile index of each node by evaluating them at energy, distance, load balancing, node density, the delay involved, and network's average energy. The proposed work ROTEE shows supreme performance against the recently proposed clustering techniques.