dvhop定位算法

① 无线网络（Wi-Fi) 毕业设计

相关范文：

无线传感器网络自身定位算法开题报告

1．概述：

无线传感器网络(WSNs)是由许多传感器节点通过自组织的形式组成的一种特殊的Ad-hoc网络，每一个传感器节点由数据采集模块、数据处理和控制模块、通信模块和供电模块等组成，此外还可能包括与应用相关的其他部分，比如定位系统、动力系统等。借助于内置多样的传感器，可以测量温度、湿度、气压、化学等我们感兴趣的物理现象。

2．研究动机：

传感器节点的自身定位是传感器网络应用的基础。例如目标监测与跟踪、基于位置信息的路由、智能交通、物流管理等许多应用都要求网络节点预先知道自身的位置，并在通信和协作过程中利用位置信息完成应用要求。若没有位置信息，传感器节点所采集的数据几乎是没有应用价值的。所以，在无线传感器网络的应用中，节点的定位成为关键的问题。

3．研究意义：

最早期的基于无线网络的室内定位系统，都采用了额外的硬件和设备，如AT&T Cambridge的Active Bat系统，采用了超声波测距技术，定位的物体携带由控制逻辑、无线收发器和超声波换能器组成的称为Bat的设备，发出的信号由安装在房间天花板上的超声波接收器接收，所有接收器通过有线网络连接；在微软的RADAR系统中，定位目标要携带具有测量RF信号强度的传感器，还要有基站定期发送RF信号，在事先实现的RF信号的数据库中查询实现定位；MIT开发了最早的松散耦合定位系统Cricket，锚节点(预先部署位置的节点)随机地同时发射RF和超声波信号，RF信号中包括该锚节点的位置，未知节点接收这些信号，然后使用TDOA技术测量与锚节点的距离来实现定位。

以上系统都需要事先的网络部署或数据生成工作，无法适用于Ad-hoc网络。现阶段研究较多的是不基于测距(Range-free)的定位算法，这样就无需增加额外的硬件，还可以减小传感器节点的体积。

4．研究目标:

(1) 较小的能耗

传感器节点所携带能源有限和不易更换的特点要求定位算法应该是低能耗的。

(2) 较高的定位精度

这是衡量定位算法的一个重要指标，一般以误差与无线射程的比值来计算，20％表示定位误差相当于节点无线射程的20％。

(3) 计算方式是分布式的

分布式的定位算法，即计算节点位置的工作在节点本地完成，分布式算法可以应用于大规模的传感器网络。

(4) 较低的锚节点密度

锚节点定位通常依赖人工部署或GPS实现。大量的人工部署不适合Ad-hoc网络，而且锚节点的成本比普通节点要高两个数量级。

(5) 较短的覆盖时间。

5.参考文献：

《无线传感器网络：体系结构与协议》作者：Edgar H. Callaway. Jr

《无线传感器网络的理论及应用》作者：王殊

《无线传感器网络节点定位算法研究》作者：端木庆敏 Publish: 2007-10-18 Hits:591

《无线传感器网络定位算法研究》作者：申屠明2007-07-11

《无线传感器网络节点自身定位算法的研究(硕士)》来自：中国文档网

《无线传感器网络DV-Hop定位算法的改进》作者：龚思来2007年07月13日

其他相关：

http://www.jianshewang.com/lunwen/cheng/txx/200811/2200.html

仅供参考，请自借鉴

希望对您有帮助

② dvhop 算法中，定位误差跟信标节点的个数与通信距离关系 我仿真出来的结果不太正确 哪位大侠指点下

你运行下这个程序，应该是正确的。
%~~~~~~~~~~ DV-Hop算法 ~~~~~~~~~~ ~~~~~~~~~~ ~~~~~~~~~~
% BorderLength-----正方形区域的边长，单位：m
% NodeAmount-------网络节点的个数
% BeaconAmount---信标节点数
% Sxy--------------用于存储节点的序号，横坐标，纵坐标的矩阵
%Beacon----------信标节点坐标矩阵;BeaconAmount*BeaconAmount
%UN-------------未知节点坐标矩阵;2*UNAmount
% Distance------未知节点到信标节点距离矩阵;2*BeaconAmount
%h---------------节点间初始跳数矩阵
%X---------------节点估计坐标初始矩阵,X=[x,y]'
% R------------------节点的通信距离，一般为10-100m
clear,close all;
BorderLength=100;
NodeAmount=100;
BeaconAmount=8;
UNAmount=NodeAmount-BeaconAmount;
R=50;
% D=zeros(NodeAmount,NodeAmount);%未知节电到信标节点距离初始矩阵；BeaconAmount行NodeAmount列
h=zeros(NodeAmount,NodeAmount);%初始跳数为0；BeaconAmount行NodeAmount列
X=zeros(2,UNAmount);%节点估计坐标初始矩阵
%~~~~~~~~~在正方形区域内产生均匀分布的随机拓扑~~~~~~~~~~~~~~~~~~~~
C=BorderLength.*rand(2,NodeAmount);
%带逻辑号的节点坐标
Sxy=[[1:NodeAmount];C];
Beacon=[Sxy(2,1:BeaconAmount);Sxy(3,1:BeaconAmount)];%信标节点坐标
UN=[Sxy(2,(BeaconAmount+1):NodeAmount);Sxy(3,(BeaconAmount+1):NodeAmount)];%未知节点坐标
%画出节点分布图
plot(Sxy(2,1:BeaconAmount),Sxy(3,1:BeaconAmount),'r*',Sxy(2,(BeaconAmount+1):NodeAmount),Sxy(3,(BeaconAmount+1):NodeAmount),'k.')
xlim([0,BorderLength]);
ylim([0,BorderLength]);
title('* 红色信标节点 . 黑色未知节点')
%~~~~~~~~~~~~~~~~~~~~~~~~~~~~初始化节点间距离、跳数矩阵~~~~~~~~~~~~~~~~~~~~~~
for i=1:NodeAmount
for j=1:NodeAmount
Dall(i,j)=((Sxy(2,i)-Sxy(2,j))^2+(Sxy(3,i)-Sxy(3,j))^2)^0.5;%所有节点间相互距离
if (Dall(i,j)<=R)&(Dall(i,j)>0)
h(i,j)=1;%初始跳数矩阵
elseif i==j
h(i,j)=0;
else h(i,j)=inf;
end
end
end
%~~~~~~~~~~~最短路经算法计算节点间跳数~~~~~~~~~~~~~~~~~~~~
for k=1:NodeAmount
for i=1:NodeAmount
for j=1:NodeAmount
if h(i,k)+h(k,j)<h(i,j)%min(h(i,j),h(i,k)+h(k,j))
h(i,j)=h(i,k)+h(k,j);
end
end
end
end
h
%~~~~~~~~~~~~~求每个信标节点的校正值~~~~~~~~~~~~~~~~~~~~~~~~~~
h1=h(1:BeaconAmount,1:BeaconAmount);
D1=Dall(1:BeaconAmount,1:BeaconAmount);
for i=1:BeaconAmount
dhop(i,1)=sum(D1(i,:))/sum(h1(i,:));%每个信标节点的平均每跳距离
end
D2=Dall(1:BeaconAmount,(BeaconAmount+1):NodeAmount);%BeaconAmount行UNAmount列
for i=1:BeaconAmount
for j=1:UNAmount
if min(D2(:,j))==D2(i,j)
Dhop(1,j)=D2(i,j);%未知节点从最近的信标获得校正值
end
end
end
Dhop
%~~~~~~~~~~~~~~~~用跳数估计距离~~~~~~~~~~~~~~~~~~~
hop1=h(1:BeaconAmount,(BeaconAmount+1):NodeAmount)%未知节点到信标跳数，BeaconAmount行UNAmount列
for i=1:UNAmount
hop=Dhop(1,i);%hop为从最近信标获得的校正值
Distance(:,i)=hop*hop1(:,i);%%Beacon行UN列；
end
% %~~~~~~~~~~~~~~~~~最小二乘法求未知点坐标~~~~~~~~~~~~~~~~~~~~~~~~
d=Distance;
for i=1:2
for j=1:(BeaconAmount-1)
a(i,j)=Beacon(i,j)-Beacon(i,BeaconAmount);
end
end
A=-2*(a');
% d=d1';
for m=1:UNAmount
for i=1:(BeaconAmount-1)
B(i,1)=d(i,m)^2-d(BeaconAmount,m)^2-Beacon(1,i)^2+Beacon(1,BeaconAmount)^2-Beacon(2,i)^2+Beacon(2,BeaconAmount)^2;
end
X1=inv(A'*A)*A'*B;
X(1,m)=X1(1,1);
X(2,m)=X1(2,1);
end
UN
X
for i=1:UNAmount
error(1,i)=(((X(1,i)-UN(1,i))^2+(X(2,i)-UN(2,i))^2)^0.5);
end
figure;plot(error,'-o')
title('每个未知节点的误差')
error=sum(error)/UNAmount
Accuracy=error/R

③ 请问有无线传感器网I加权质心算法matlab代码吗

[capture-of-moving.rar] - 本文详细介绍了在视频图像的基础上用!"#$ & ’(( )*+ 实现运动目标形心捕获的具体程序"从而可以实现运动 目标的位置检测 程序运用改进的形心算法计算目标图形 的中心坐标"并使用了计时器函数实时显示坐标变化值
[codebook.rar] - 实现了基于码书的运动检测，并有与其他的检测算法做对比，例如MOG，Bayes，三帧差分等。
[xin.rar] - 无线传感器网络加权质心自定位算法中加权质心算法仿真

[qq1_2.rar] - 3种定位算法（多边：3 边及4边 最小二乘 质心）的主程序
[802.11opnet.rar] - 802.11opnet，802.11在OPNET中的仿真代码
[rssic.rar] - 无线传感器网络的加权质心算法，用matlab编程的，需要的可以参考
[Simulation1.rar] - 本程序先使用RSSI中对数常态模型来测距离，然后用三边测量法来计算未知节点的坐标。
[RSSIxin.rar] - 基于RSSI测距的无线传感器网络改进质心定位算法
[xinsuanfa2.rar] - 无线传感器网络中质心算法，并有锚节点比例和误差分析
[myDVHOP.rar] - 一种基于RSSI的DV-HOP加权算法，该算法基于节点接收信标节点位置元组时的信号强度（RSSI）对邻居节点间跳数进行加权处理，将节点间的跳数与距离相关联，仿真试验结果证明该加权算法可大大提高定位精度。

④ 跪求一篇3000汉字（英译汉）的外文文献

With the large-scale development of mobile communication technology and the coming of the 3G era, wireless location technology of cellular network is more and more mature in theory, also appeared more and more research in application, the localization technology in cellular communication system not only provides the position information service for the users, emergency assistance and goods-tracing function, in ensuring national security and crime also play an effective role. Basic principle of wireless cellular network positioning system is in a cellular network, according to the location of the mobile station (characteristic parameters such as arrival time TOA, the time difference of arrival TDOA, angle of arrival, AOA) were measured and the estimation of the location of the mobile station, the mobile location. Firstly, this paper introces the application of the wireless location technique in cellular networks, the cellular network system and various common positioning technology are discussed. Secondly, this paper introces the TOA positioning algorithm based on the basic principle and mathematical model of TDOA location algorithm in cellular network, analysis of the NLOS error model and its influence on the positioning system, at the same time of the traditional localization algorithm (such as Chan algorithm, Fang algorithm, Friedlander and Taylor series expansion method) were studied, too the analysis of location algorithm for a NLOS error. Finally, this paper introces the positioning technology based on OFDM signal, introces the positioning using OFDM signal strengths, the OFDM signal TOA estimation algorithm and localization algorithm has concted the simulation research.AdHoc network is a self-organizing network, which has no communication infrastructure support can be communication between mobile nodes in a few. The adhoc has flexible networking, resource characteristics such as effective utilization, it will have broad application prospects in military communications, emergency communications, business application environment. However, at the same time, because of its high bit error rate, limited battery capacity, easy to be monitored and other issues, we need to constantly improve and perfect. AdHoc network is a new network, there are still a lot of problems, the realization, practical and a lot of work to do. Because the AdHoc network of multi-hop wireless transmission and the network topology changes, TCP performance than the wired network deterioration. How to solve the problem of TCP application in AdHoc network is facing an urgent problem to be solved. Now the main research direction of TCP to improve the performance of AdHoc network focus on the improvement of MAC layer, network layer, transport layer mechanisms, and improved based on the original architecture has been added a layer. TCP is the core of congestion control mechanism. The current version of TCP are mainly Tahoe, Reno, NewReno, SACK and Vegas several, and an improved scheme for wireless networks called DA. Congestion control mechanism of TahoeTCP is divided into three stages, namely, slow start, congestion avoidance, fast retransmission. Several TCP are based on TCPTahoe, but all were improved, so that TCP can run more efficiently or suitable for a particular network state. RenoTCP is currently the most widely used in the Internet version of TCP. It increases fast recovery based on Tahoe. NewRenoTCP is a small improvement in RenoTCP, it solves the RenoTCP in fast recovery of multiple packet lost problem. Selective acknowledgement (SACK) through the receiver selectivity for data validation to improve the performance of TCP, it can solve a window lost packets problem. DA is the mechanism, it is specially designed for wireless networks to improve the shared channel to do. VegasTCP has a congestion is completely different from the former five TCP control mechanism. Three kinds of technology of Vegas is mainly used to improve throughput reces loss. Because the TCP is designed for wired networks, it is premise of effective operation of the assumption that packet loss is caused by network congestion. TCP the packet loss as network has signs of congestion, each detects a packet loss, TCP will start the congestion control mechanism, rece the sending rate of the sender, thereby recing the congestion degree. But in the AdHoc network, packet loss are not by network congestion. The high error rate of wireless channel, caused by node movement route interrupt, MAC layer conflicts can cause packet loss, then start the TCP congestion control is not necessary, so that the throughput of TCP significantly decreased. In order to make TCP better adapt to the AdHoc network, needs to be improved. NS is the acronym NetworkSimulator, which is composed of LBNL () network simulation tool developed by the research team. NS is an extensible, configurable, programmable event driven network simulation software. The simulation in this paper are based on the NS2. The performance of various versions of TCP in AdHoc network is simulated, and the effects of the AdHoc network is a multihop and mobile characteristics on the performance of TCP, and TCP properties of the various versions of the comparison, find out under various conditions is most suitable for AdHoc network TCP. Then the performance of the DA mechanism for wireless networks is applied to the AdHoc network has made the further analysis and put forward the improvement on it. TCP improve the performance of AdHoc network and then a variety of published literature has been proposed in the scheme are summarized and their evaluation, including the improvement of the MAC layer, to improve the network layer, to improve the transport layer, improve the comprehensive improvement and other aspects. The improvement was mostly focused on the network layer and above, and the improved plan mostly increases the complexity of the algorithm, this is very adverse to the mobile node energy limited. Main reason for the decline in performance of multi-hop TCP adhoc networks is not the stability of the MAC layer of the exposed terminal problem and binary backoff mechanism inced by TCP, so the AdHoc network MAC layer is improved, the first is not stability for the AdHoc network e to the multi-hop characteristic causes the TCP to put forward their own improvement, and analysis the results of simulation and improvement. Then the improved scheme is put forward on the channel exists in multi-hop adhoc networks to lock the unfairness caused, and simulation analysis proved that the improvement can not only improved AdHoc network has many unfair problems of connection, not stability but also can improve TCP, increase throughput, the two improved are relatively simple, no increase of mobile node energy consumption and network load, mobility is not suitable for adhoc network.
翻译：随着移动通信技术的大规模发展，3G时代的到来，蜂窝网无线定位技术在理论上是越来越成熟，也出现了越来越多的应用研究，蜂窝移动通信系统定位技术不仅提供位置信息服务的用户，紧急援助和货物跟踪功能，在确保国家安全的犯罪也发挥有效的作用。无线蜂窝网络定位系统的基本原理是在蜂窝网络中，根据移动台的位置（特征参数，如到达时间TOA，TDOA的到达时间差的到达，AOA，角）进行了测量和移动台的位置的估计，移动位置。首先，本文介绍了无线定位技术在蜂窝网络中的应用，蜂窝网络系统和各种常见的定位技术进行了讨论。其次，本文介绍了基于的基本原理和在蜂窝网络的TDOA定位算法数学模型的TOA定位算法，对NLOS误差模型和定位系统的影响分析，在传统的定位算法相同的时间（如Chan算法，Fang算法，弗里德兰德和泰勒级数展开法）进行了研究，也对NLOS误差的定位算法分析。最后，本文介绍了基于OFDM信号的定位技术，介绍了采用OFDM信号强度的定位，OFDM信号TOA估计算法和定位算法进行了仿真research.adhoc网络是一种自组织网络，没有通信基础设施的支持，可在一些移动节点之间的通信。AdHoc具有组网灵活等特点，资源的有效利用，将有广阔的应用前景，在军事通信，应急通信，商业应用环境。然而，在同一时间，因为它的误码率高，电池容量有限，容易被监测和其他问题，我们需要不断的改进和完善。Ad Hoc网络是一种新的网络，还存在很多问题，实现，做实践和大量的工作。由于多跳无线AdHoc网络传输和网络拓扑结构的变化，比有线网络的TCP性能恶化。如何解决自组织网络中的TCP应用问题是面临的一个迫切需要解决的问题。目前主要研究方向的TCP改善AdHoc网络的集中在MAC层的性能，提高网络层，传输层机制，并基于原有体系结构改进增加了一层。TCP拥塞控制机制的核心是。当前的TCP版本主要是太浩湖，雷诺，NewReno，SACK和Vegas几种，和一种改进的无线网络方案称为大。tahoetcp的拥塞控制机制分为三个阶段，即，慢启动，拥塞避免，快速重传。TCP是基于tcptahoe，但都进行了改进，使TCP可以更高效地运行或适合特定的网络状态。renotcp是目前在TCP网络版，使用最广泛的。它增加了基于Tahoe快速恢复。newrenotcp是renotcp小改进，解决了renotcp中的多个数据包的快速恢复丢失的问题。选择性确认（SACK）通过接收器的选择性数据验证提高TCP的性能，它可以解决一个窗口的数据包丢失的问题。大的机构，它是专为无线网络提高共享信道的去做。vegastcp具有拥塞控制机制TCP从以前的五完全不同。三种技术的拉斯维加斯主要用于提高吞吐量降低