无线传感器网络中Robust Position定位算法的改进

Improvement of Robust Position location algorithm in wireless sensor network

赵巍[1,2] 庞慧[1]

首先深入分析了两种典型的分布式的节点定位算法，并从定位精度及能量消耗两个方面给出了定量分析结果。在此基础上提出了改进的定位算法，BB_RP算法。通过仿真试验，在定位精度和能量消耗两个方面与原有算法进行定量的分析比较。结果表明，BB_RP算法虽然在定位精度略低于原有的算法，但是在能量消耗和覆盖速度两个指标上有了较大的提高，使得无线传感器网络的生命周期延长。[著者文摘]

Two typical distributed node location algorithms were analyzed in this paper firstly,and it gave the analysis result of location precision and energy consumption. A modified node location algorithm, named BB _ RP algorithm, was presented. By simulating test, it is compared withthe primary algorithms about node location precision and energy consumption. Comparing result showed that the node location precision of BB _ RP is a little lower than that primary algorithms, but it makes great improvement in energy consumption and coverage speed and delays the lifetime of wireless sensor network.[著者文摘]

水下无线传感器网络的节点精确定位

Accurate Node Localization in Underwater Wireless Sensor Networks

周伟[1] 来鸿飞[2] 刘忠[1]

以无线传感器网络（WSN）水下应用为背景,针对特定的环境要求,提出了一种可实现网络规模升级的分布式无锚点网络节点自定位机制。该定位算法通过距离误差估计和分布式坐标计算方法,有效地减少了由于测量距离误差所带来的坐标计算误差和节点坐标计算所带来的通信开销,有利于网络节点能量的合理使用和大规模的WSN布放。通过试验仿真计算,验证了该定位机制的合理性,为水下WSN应用提供了有力的技术支持。[著者文摘]

Due to wireless sensor networks in the underwater environment where an infrastructure does not exist and GPS cannot be used, the paper propose a scalable and distributed GPS-free position protocol that is capable of node discovery and relative location. This algorithm makes each node estimate the distance to neighboring nodes that are within its transmission range with Time of Arrival （TOA） technology. It formulates a gradient descent method to minimize the distance-measurement error in nodes local positioning. It compares the performance of this algorithm against existing mechanisms in simulating experiments, and the results show that the proposed method is able to support the underwater deployment of large scale sensor networks efficiently and precisely.[著者文摘]

基于可连Cell的无线传感器网络拓扑控制算法

A Connectible-Cell Based Topology Control Algorithm for Wireless Sensor Networks

金鑫 熊焰 李旻 岳丽华

在无线传感器网络的拓扑控制（TC）中，基于Cell的TC算法被认为是一类可以节省传感器节点能量并延长网络生命周期的方法，但是其需要较多的骨干网节点并且无法保证连通性．通过分析现今算法的内在局限性，提出了一种1-Con思想：当一个Cell的头节点被加入当前骨干网时，所有其可以连接的Cell使用该节点连入拓扑结构，然后此新骨干网递归地继续扩大．基于此思想，设计了一种基于可连Cell的拓扑控制算法（CCTC），并从理论上证明：1）CCTC可以保证其所形成的拓扑结构维持网络连通；2）每一轮用于形成骨干网的工作节点非常少．CCTC的计算复杂度是线性的，空间复杂度和信息交换量都是常数量级．仿真实验同样显示，CCTC可以在提供良好鲁棒性和较少的消息交换的情况下，更有效地节省节点能耗并延长网络生命周期．[著者文摘]

In wireless sensor networks topology control （TC）, cell based TC algorithms have been recognized as a type of methods which could conserve nodes＇ energy and extend network lifetime. However, they require too many backbone nodes and can＇t guarantee connectivity. By investigating the limitations of these algorithms, a 1-con method is proposed： when a cell head is connected into the current backbone, all cells that could be reached by this head will be connected to the topology structure through it, and then the new backbone expands itself recursively in this way. By leveraging the 1-con method, a connectible-cell based topology control algorithm （CCTC） is designed. It could be theoretically proved that 1） CCTC could guarantee the network connectivity; and 2） In every round, CCTC needs fewer active nodes than other algorithms do. The computing complexity of CCTC is linear; and the storage space and the message amount are bounded by constant magnitude. Simulation results also validate that CCTC provides impressive energy conservation and longer network lifetime with decent robustness and limited control overheads.[著者文摘]

可变周期的无线传感器时间同步算法

Changeable cycle for time synchronization algorithm in wireless sensor networks

杨景源 李向阳

时间同步技术是无线传感器网络应用中的一项关键技术。介绍了几种无线传感器网络的主流同步算法。通过对比，总结了各种算法的优点和限制条件。最后提出了可变周期的无线传感器时间同步算法，该算法利用改进的参考广播同步协议估计时间偏差和速率偏差，并通过估计出来的偏差值动态调整下次同步的周期，达到减少同步次数，节约能量的目的。[著者文摘]

Time synchronization plays a critical role in wireless sensor networks （WSNs）. First several kinds of time synchronizationalgorithms for WSNs are introduced in detail, then by comparing them, figure out the advantages and disadvantages of each kind respectively. In the end, a time synchronization algorithm based on changeable cycle is proposed. This algorithm use the advanced reference broadcast synchronization to estimate the clock drift and clock offset, and then adjust the next synchronized cycle dynamic based on those two estimated parameters so as to decrease the synchronization times as well as reduce the energy consumption.[著者文摘]

无线传感器网络自适应并发多路由算法

A Parallel Multi-Path Algorithm for Adaptive Routing in Wireless Sensor Networks

吴震东[1,2] 李善平[1]

无线传感器网络地理位置路由算法需要克服本地最小化现象.已有的算法均以“右手规则”为基础来克服这一现象,但是,“右手规则”会损失链路且难以在路由过程中动态调整所选路由,对自适应多路由选择不利.通过深入分析本地最小化现象,发现合理限定贪心算法的选路区域可以克服本地最小化现象,由此提出Clockwise Rule,该规则不损失链路,可动态调整所选路由,耗费低.在此基础上,提出了自适应并发多路由算法APMR（Adaptive Parallel Multi-path Routing）.算法是分布式的,可在任意中继节点处动态调整路由策略,优化路由过程.仿真结果表明APMR算法对网络性能有很好的改善.[著者文摘]

Geographic muting in wireless sensor networks suffers from the local minimum phenomenon. To help packets get out of local minimum phenomenon,the long-known right-hand rule is used, which needs the graphs planarizing. It will lost many links and doesn＇ t suit adaptive routing. Through studying the local minimum phenomenon deeply, we find out that greedy forwarding in restricting routing regions could deal with the local minimum phenomenon. Based on the observation, a new method Clockwise Rule was proposed, which does not lost any links and more suits adaptive routing. We also proposed an adaptive parallel multipath routing algorithm （APMR） using Clockwise Rule, which can provide various routing strategies and switch these strategies at relay nodes freely. Simulations show that APMR can significantly improve the performance of wireless sensor networks.[著者文摘]

基于立方体剖分的传感器网络快速三维k-覆盖判定算法

Cube partitionbased rapid three-dimensional k-coverage decision algorithm for sensor networks

姚焯善 王雷 汤念 张大方

提出了一种传感器网络中基于立方体剖分的三维k-覆盖快速判定算（CP-RTCDA）和三维最大k-覆盖问题的快速求解算法（CP—RTMCDA）。算法首先把感兴趣区域剖分为立方体区域。从而将复杂的空间区域覆盖问题转化为简单的立方体区域覆盖问题。理论分析与仿真实验表明，针对具有n个节点的传感器网络，新算法的计算时间复杂度为O（n），远低于已有算法O（n^3logn）的计算时间复杂度。[著者文摘]

A Cube Partition based Rapid Three-dimensional k-Coverage Decision Algorithm （CP-RTCDA）was proposed, in which the region of interest was partitioned into triangles firstly, and then the complex area coverage problem was transformed into simple triangle coverage problem. Theoretical analysis and simulation results show that, for sensor networks with different sensors, the new algorithm can solve the k-coverage problem correctly for any given region of interest with time costs of O （ n ） only, which is far below the time costs O （ n^3 logn ） of other algorithms.[著者文摘]

浆液下机器人定位功能实现

Achievement for orientation function of underwaterstirring robots

刘伟明 郝静如 黄民

设计液下搅拌机器人的定位系统，选用多传感器来获取定位信息。用单片机（下位机）测得各个传感器信息，通过RS-485总线把信息传给工控机（上位机），工控机对信息进行融合，实时（本系统可达1s）获得机器人的位置及航向信息。实验验证定位系统可行性，并对测距误差进行了分析，修正后定位误差在10cm以内，满足对机器人的定位要求。[著者文摘]

An orientation system for stirring robots working under water is designed. Multi-sensors are selected to get the orientation information. The information is captured by the MCU,carried through RS-485 bus to industrial PC and merged by it, then the position and heading information that can be updated in one second is promptly displayed. A laboratory is done to validate the feasibility of the orientation system and then the distance errors up to under 10 cm that can satisfy the demand are corrected.[著者文摘]

基于单目视觉的移动机器人全局定位

Monocular-Vision-Based Mobile Robot Global Localization

厉茂海[1] 洪炳镕[1] 罗荣华[2] 蔡则苏[1]

提出在基于单目视觉创建的环境地图中实现移动机器人全局定位．基于KD树的最近邻搜索实现特征匹配．应用尺度不变特征变换（SIFT）方法提取特征，并用多维向量描述，保证了对图像光强变化、尺度缩放、三维视角和噪声具有不变性．提出了一种基于RANSAC的鲁棒定位方法．在实际室内环境Pioneer3机器人上进行的实验表明本文提出方法高效、可靠．[著者文摘]

An environmental map built with monocular vision is used to implement mobile robot global localization. The feature matching is implemented with the KD-tree-based nearest search approach. The features are extracted with Scale Invariant Feature Transform （SIFF）, and discribed with highly distinctive multi-dimensional vector, making features be invariant to changes in illumination, scale, 3D viewpoint and noise. A robust localization based on RANSAC （RANdom SAmple Consensus） approach is presented. Experiments on robot Pioneer 3 with monocular CCD camera in our real indoor environment show that our method is of high precision and stability.[著者文摘]