Balancing the power consumption speed in flat and hierarchical WSN

A combination of a cluster tree routing protocol and an Ad hoc on demand vector (AODV) routing protocol is used in the latest ZigBee standard wireless sensor networks (WSNs) technology. However, the AODV routing protocol has no means by which to take into consideration the power consumption of the nodes during the routing process. Therefore, a new approach is proposed in this paper to balance the power consumption speed and to distribute the responsibilities of routing among fiat wireless sensor nodes and the three levels of hierarchical wireless sensor nodes. These three levels are based on the three types of devices, which are used in the ZigBee standard: the coordinator, the touters, and the end devices. In this paper, we have compared the original AODV routing protocol with our extension approach for the distribution of power consumption. Based on the simulation results, our new approach has achieved better performance in terms of increasing the lifetime of the fiat wireless sensor network, the personal area network (PAN)coordinator, the touters, and the whole network of the hierarchical wireless sensor network. Additionally, it has better performance in terms of distributing the power consumption among the key nodes of the wireless sensor network.     

A new scheme of digital communication using chaotic signals in MIMO channels

This paper proposes a new digital communication scheme,which uses chaotic signals based on the adaptive synchronization and parameter identification technique of chaotic systems reported recently.Due to the multi signal character,this scheme combines the chaotic signal transmission with the MIMO channel technique in a wireless environment,which is different from the traditional chaotic communication frameworks.From a practical perspective,an outline of modulation,channel model,demodulation and non-coherent detection is investigated.Furthermore,system performance is evaluated by simulations,and improvements on this scheme are also discussed.     

A QoS-aware routing algorithm based on ant-cluster in wireless multimedia sensor networks

QoS-aware routing algorithm is important in wireless multimedia sensor networks. This paper formulates a generalized QoS-aware routing model on the basis of multiple routing metrics and priorities of packets. We first introduce a 2D plain-based routing algorithm IPACR which improves the standard ant colony algorithm by optimizing the initial distribution of artificial pheromone in order to accelerate the algorithm convergence rate. Then a clustering-based routing algorithm ICACR is presented which can be well applied in a large scale network. ICACR is a variation of IPACR because it can be suitable for clustering cases to satisfy the larger scale situations. Both the numerical algorithm performance analysis and simulation of IPACR and ICACR are given. The results show that ICACR outperforms IPACR in terms of both network lifetime and QoS-aware routing metrics in large scale wireless multimedia sensor networks. Moreover, the simulation based on the real video traces shows that by extending the multi-path to ICACR for different priorities of video frames better performance can be achieved.     

Energy-efficient multipath routing in wireless sensor network considering wireless interference

Due to the energy and resource constraints of a wireless sensor node in a wireless sensor network (WSN), design of energy-efficient multipath routing protocols is a crucial concern for WSN applications. To provide high-quality monitoring information, many WSN applications require high-rate data transmission. Multipath routing protocols are often used to increase the network transmission rate and throughput. Although large-scale WSN can be supported by high bandwidth backbone network, the WSN remains the bottleneck due to resource constraints of wireless sensors and the effects of wireless interference. In this paper, we propose a multipath energy-efficient routing protocol for WSN that considers wireless interference. In the proposed routing protocol, nodes in the interference zone of the discovered path are marked and not allowed to take part in the subsequent routing process. In this way, the quality of wireless communication is improved because the effects of wireless interference can be reduced as much as possible. The network load is distributed on multiple paths instead of concentrating on only one path, and node energy cost is more balanced for the entire wireless network. The routing protocol is simulated in NS2 software. Simulation result shows that the proposed routing protocol achieves lower energy cost and longer network lifetime than that in the literature.     

Integrating local and partial network view for routing on scale-free networks

Traditional routing schemes,such as OSPF,optimize data plane routing efciency by maintaining full view of the network at the control plane.However,maintaining full network view and handling frequent routing information updates are costly in large-scale complex networks,which are considered to be the root causes for the routing scalability issue.Recently,it is suggested that routing on local or partial information is plausible if slight performance degradation is acceptable.This paper proposes a routing scheme,operating on an integrated network view at each node that consists of its local neighborhood and a globally unique skeleton tree.This scheme signifcantly reduces storage,communication and processing costs.On scale-free networks,this beneft only comes at the cost of marginal performance degradation,which implies that it is not worthwhile to do shortest path routing based on full view of the network on scale-free networks.In contrast,the routing efciency is severely aggravated on purely random networks,indicating the inappropriateness of this scheme and the rationality of maintaining full network view on random networks.     

Channel Aware Opportunistic Routing in Multi-Radio Multi-Channel Wireless Mesh Networks

Opportunistic routing （OR） involves multiple candidate forwarders to relay packets by taking advantage of the broadcast nature and multi-user diversity of the wireless medium. Compared with traditional routing （TR）, OR is more suitable for the unreliable wireless link, and can evidently improve the end to end throughput. At present, there are many achievements concerning OR in the single radio wireless network. However, the study of OR in multi-radio wireless network stays the beginning stage. To demonstrate the benefit of OR in multi-radio multi-channel network, we propose a new route metric -- multi-channel expected anypath transmission time （MEATT）, which exploits the channel diversity and resource of multiple candidate forwarders for OR. Based on the new metric, a distributed Mgorithm named Channel Aware Opportunistic Routing （CAOR） is proposed. The simulation results demonstrate that MEATT improves 1.14 and 1.53 times of the average throughput than existing expected anypath transmission time （EATT）and metric of interference and channel switching cost （MIC） respectively. The average delay of MEATT is 17% and 40% lower than those of EATT, MIC, respectively.     

Random Walk Routing in WSNs with Regular Topologies

Topology is one of the most important characteristics for any type of networks because it represents the network's inherent properties and has great impact on the performance of the network. For wireless sensor networks (WSN), a well-deployed regular topology can help save more energy than what a random topology can do. WSNs with regular topologies can prolong network lifetime as studied in many previous work. However, little work has been done in developing effective routing algorithms for WSNs with regular topologies, except routing along a shortest path with the knowledge of global location information of sensor nodes. In this paper, a new routing protocol based on random walk is proposed. It does not require global location information. It also achieves load balancing property inherently for WSNs which is difficult to achieve by other routing protocols. In the scenarios where the message required to be sent to the base station is in comparatively small size with the inquiry message among neighboring nodes, it is proved that the random walk routing protocol can guarantee high probability of successful transmission from the source to the base station with the same amount of energy consumption as the shortest path routing. Since in many applications of WSNs, sensor nodes often send only beep-like small messages to the base station to report their status, our proposed random walk routing is thus a viable scheme and can work very efficiently especially in these application scenarios. The random walk routing provides load balancing in the WSN as mentioned, however, the nodes near to the base station are inevitably under heavier burden than those far away from the base station. Therefore, a density-aware deployment scheme is further proposed to guarantee that the heavy-load nodes do not affect the network lifetime even if their energy is exhausted. The main idea is deploying sensors with different densities according to their distance to the base station. It will be shown in this paper that incorporating the random walk routing protocol with the density-aware deployment scheme can effectively prolong the network lifetime.     

Joint routing, scheduling, and power control for multichannel wireless sensor networks with physical interference

Reliability and real-time requirements bring new challenges to the energy-constrained wireless sensor networks, especially to the industrial wireless sensor networks. Meanwhile, the capacity of wireless sensor networks can be substantially increased by operating on multiple nonoverlapping channels. In this context, new routing, scheduling, and power control algorithms are required to achieve reliable and real-time communications and to fully utilize the increased bandwidth in multichannel wireless sensor networks. In this paper, we develop a distributed and online algorithm that jointly solves multipath routing, link scheduling, and power control problem, which can adapt automatically to the changes in the network topology and offered load. We particularly focus on finding the resource allocation that realizes trade-off among energy consumption, end-to-end delay, and network throughput for multichannel networks with physical interference model. Our algorithm jointly considers 1) delay and energy-aware power control for optimal transmission radius and rate with physical interference model, 2) throughput efficient multipath routing based on the given optimal transmission rate between the given source-destination pairs, and 3) reliable-aware and throughput efficient multichannel maximal link scheduling for time slots and channels based on the designated paths, and the new physical interference model that is updated by the optimal transmission radius. By proving and simulation, we show that our algorithm is provably efficient compared with the optimal centralized and offline algorithm and other comparable algorithms.     

Reliable energy-efficient routing with novel route update in wireless sensor networks

In this paper we introduce a novel energy-aware routing protocol REPU (reliable, efficient with path update), which provides reliability and energy efficiency in data delivery. REPU utilizes the residual energy available in the nodes and the received signal strength of the nodes to identify the best possible route to the destination. Reliability is achieved by selecting a number of intermediate nodes as waypoints and the route is divided into smaller segments by the waypoints. One distinct advantage of this model is that when a node on the route moves out or fails, instead of discarding the whole original route, only the two waypoint nodes of the broken segment are used to find a new path. REPU outperforms traditional schemes by establishing an energy-efficient path and also takes care of efficient route maintenance. Simulation results show that this routing scheme achieves much higher performance than the classical routing protocols, even in the presence of high node density, and overcomes simultaneous packet forwarding.     

A simple fault-tolerant adaptive and minimal routing approach in 3-D meshes

In this paper we propose a sufficient codition for minimal routing in 3-dimensional (3-D) meshes with faulty nodes,It is based on an early work of the author on minial routing in 2-dimensional(2-D) meshes,Unlike many traditional models that assume all the nodes know global fault distribution or just adjacent fault information,our approach is based on the concept of limited global fault information,First,we propose a fault model called faulty cube in which all faulty nodes in the system are contained in a set of faulty cubes.Fault information is then distributed to limited number of nodes while it is still sufficeint to support minimal routing.The limited fault information collcted at each node is represented by a vector caaled extended safety level.The extended safety level associated with a node can be used to determine the existence of a minimal path from this node to a given destination .Specifically,we study the existence of minimal paths at a given source node,limited distribution of fault information,minimal routing,and deadlock-free and livelock-free routing.our results show that any minimal routing that is partially adaptive can be applied in our model as long as the dstination node meets a certain conditon.We also propose a dynamic planar-adaptive routing scheme that offers better fault tolerance and adaptivity than the planar-adaptive routing scheme in 3-D meshes.Our approach is the first attempt to address adaptive and minimal routing is 3-D meshes with faulty nodes using limited fault information.     

Novel route maintenance protocols for the Bluetooth ad hoc network with mobility

Bluetooth technology is specially designed for the wireless personal area networks to replace cable. Several challenges exist in Bluetooth scatternet formation and routing, since nodes can arrive and depart at arbitrary times. In this paper, novel route maintenance algorithms are proposed for the Bluetooth ad hoc networks, where nodes can enter or exit from the piconets time to time. Our protocols guarantee the connectivity among nodes and reconstruct the routes dynamically by considering location information of the nodes. Besides, it is proposed how to reduce the number of hops and to form the shortest route between the source and the destination due to addition of new nodes to a piconet. Performance analysis of our protocols show that they outperform in terms of end to end transmission delay, bandwidth consumption and average hop counts as compared to similar Bluetooth routing protocols that we have considered.     

Adaptive frequency hopping and power control based on spectrum characteristic of error sources in Bluetooth systems

In this paper, we propose a new adaptive frequency hopping (AFH) and power control (PC) scheme to mitigate co-channel interferences and channel noise in the Bluetooth systems. We consider a two-step interference mitigation scheme exploiting the spectrum characteristic of the interference source and channel noise. Good channels without IEEE 802.11x based wireless local area networks (WLAN) interference are first estimated by considering wideband characteristic of WLAN. Then, channel noise and interference from other Bluetooth devices in good channels are, respectively, mitigated by PC and AFH based on narrowband characteristic of Bluetooth. The performance of the proposed scheme is verified by computer simulation. Simulation results show that the proposed mitigation scheme significantly outperforms conventional schemes.     

蓝牙技术在煤矿数据传输中的应用研究

文章分析了802.11b(无线局域网技术)、HomeRF(家庭无线局域网技术)、IrDA(红外技术)和蓝牙技术等各种短距离无线通信技术的优缺点,根据煤矿现场的实际情况,选择了蓝牙无线通信技术解决煤矿短距离数据传输的难题。文章提出了基于蓝牙技术的无线数据传输系统总体方案;分析了蓝牙通信原理与协议规范、蓝牙串口仿真协议(RFCOMM);以蓝牙串口应用框架为前提,确定了蓝牙通信替代电缆传输的实现模式;以CSR公司的单芯片蓝牙模块为核心,设计了系统的硬件电路;以蓝牙设备为基础,构建了点对点的数据传输系统硬件平台;提出了基于串口仿真协议的软件算法流程;根据蓝牙串口应用框架,设计了系统应用程序并在系统硬件平台上实现。实验结果表明,蓝牙模块RFCOMM服务功能完善,系统性能基本稳定。     

一种基于蓝牙的交互式系统设计与实现

随着无线互联技术和移动终端技术的发展,手机等移动终端用户对蓝牙产品的功能提出了更高的要求。蓝牙采用推送技术进行数据传输,用户只能选择是否接收,不能对蓝牙发送端的数据进行自主交互浏览。采用J2ME和蓝牙技术实现一种在移动蓝牙终端上使用的交互式系统,有效地利用了J2ME 跨平台的优势,以及蓝牙传送数据易用性和实用性等优点。根据对JSR82规范提供的Java蓝牙无线技术API的研究,给出了蓝牙交互式系统的设计方案和系统结构。通过J2ME的无线应用开发包和MIDlet编程模型,实现了交互式系统。     

矿井下基于蓝牙技术的语音通讯控制器设计

提出一种基于蓝牙技术的矿井下无线语音通讯控制器设计方案,解决了蓝牙语音传输在特殊环境下容易受到外界干扰的问题;在语音通讯控制器系统结构中,采用ROK101 007蓝牙芯片做为无线通信模块,使用MSM7570芯片完成语音编解码;详细介绍了软、硬件的设计,使该语音通讯控制器达到本安型标准,从而适合在矿井下的特殊场合使用,经试用后,该语音通讯控制器传输话音清晰稳定。     

蓝牙技术的安全机制

蓝牙作为一种新兴的无线通信技术,受到了人们的广泛关注。本文介绍了蓝牙的安全架构,认证和加密的实施过程,对其在各方面的安全缺陷进行了分析。     

蓝牙工业现场总线应用模型

该文对传统有线工业现场总线网络中存在的问题进行了比较全面的分析,结合无线蓝牙技术特点,提出了一种简单可行的无线蓝牙工业现场总线应用模型,较好的解决了有线工业现场总线存在的问题。这种应用模型实现了有线工业现场总线的功能,还实现了无线蓝牙工业现场总线与有线工业现场总线的网络互联,并保证了两种网络的互操作。该文还介绍了一种基于该模型实现的蓝牙工业现场总线原型系统。     

蓝牙与802．11b视频流传输性能研究和比较

目前无线ad hoc网络发展的目标是支持多媒体数据的传输，基于ad hoc网络的视频流传输有着巨大的应用前景。但是无线传输介质的不稳定特性决定了其支持视频流传输存在较大的挑战。在分析蓝牙和802．11b技术各自优缺点的基础上，设计了基于蓝牙和802．11b无线ad hoc网络视频流传输的模拟实验架构。在不同码率和不同路径长度的模拟环境下测试了解码视频流的质量，研究、对比了二者在视频流传输中的性能。     

蓝牙技术和LabVIEW在自行式防空武器系统性能测试中的应用

针对传统信号测试设备在自行式防空武器系统性能测试中的不足,设计实现了一种基于蓝牙技术和LabVIEW的无线信号测试系统。详细介绍了数据采集、无线传输和数据处理显示的软、硬件设计方案。     

基于LoRa、蓝牙和安卓手机的AUV手柄遥控系统设计

为实现AUV手柄遥控模式不增加AUV无线电通信硬件开销,且为了实现该功能模式的低成本、易实现、全透明和自定义,设计了AUV手柄遥控指令经指控台中转的AUV手柄间接遥控方案;方案硬件上以安卓手机为遥控手柄,配套遥控手柄APP软件实现手柄操作,通过手机蓝牙与指控台计算机蓝牙进行近距离点对点连接,以蓝牙无线通信实现手柄遥控指令对指控台的传输,之后指控台通过LoRa无线通信实现手柄遥控指令对AUV的无线传输;方案试验验证环节以Arduino开发板模拟指控台,结合无线蓝牙收发模块接收手机遥控手柄发来的遥控指令,实现了10米间距20Hz数据帧蓝牙通信,结合LoRa模块进行遥控指令的无线发送,以AUV无线通信板进行LoRa接收,并对收到的遥控指令进行解析和执行,实现了1000米间距9600bps速率的LoRa通信;最终通过点灯试验、打舵试验和推进器试验证明了该设计方案链路完整可行并应用到工程实践。