gusucode.com > 信道仿真的很好程序,可以实现不同参数情况下的信道仿真,比如超宽带系统的室内多径环境信道仿真 > 信道仿真/logtest.m
function q=logtest(data,bins) %chi-square testing for lognormal distribution %Gayatrii Prabhu and P. M. Shankar y=sort(data./mean(data)); %unity mean sig=sqrt(log(std(y)^2+1)); %parameter sigma for lognormal mu=-sig^2/2; %second parameter for lognormal inter=max(y)-min(y); %interval for chi-square test intstep=inter/bins; %size of sub-interval intval=[min(y):intstep:max(y)]; %samples at the sub-intervals k=[zeros(1,bins)]; %number of samples in each sub-interval %counting the samples in each sub-interval for i=1:length(y) for j=1:bins if y(i)<=intval(j+1) k(j)=k(j)+1; break; end; end; end; Fy=logncdf(intval,mu,sig); %cdf at each sub-interval sample p=zeros(1,bins); for i=1:bins p(i)=Fy(i+1)-Fy(i); %probabilities at the sub-interval samples end; np=p.*length(y); q=0; for i=1:bins q = q + ((k(i)-np(i))^2)/np(i); %chi-square test statistic end;