无线传感器网络定位DV_HOP算法的实现（MATLAB）

%~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 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=250; BeaconAmount=25; UNAmount=NodeAmount-BeaconAmount; R=60; Dall=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