What does toeplitz do in this code?

hello.can anyone help me to understand this code about mimo correlated fading channel?i

will be forever greatful.

function hh=channel coeff(NR,NT,n,rtx,rrx,type)
h=sqrt(1/2)*(randn(nr*nt,n)+j*randn(nr*nt,n))
if nargin,hh=h; return,end
if isvector(rtx)=toeplitz(rtx);
if isvector(rrx),toeplitz(rrx);

if strcmp(type,'complex')
c=chol(kron(rtx,rrx));
else
c=sqrtm(sqrt(kron(rtx,rrx)));
end
hh=zeros(nr,nt,n);
for i=1:n
tmp=c*h(: ,);
hh(: , : , i)=reshape(nr*nt*n);
end

[Matt J]

Looks like a coding bug to me.

[Guillaume]

if isvector(rtx)=toeplitz(rtx);

is not valid matlab syntax. The = is illegal there, and the if appears to be missing a matching end

if isvector(rrx),toeplitz(rrx);

is also missing a matching end. Otherwise the syntax is legal but since the result of toeplitz is not assigned to anything, the whole thing is pointless.

Perhaps the best person to ask about this code is the author.

I wouldn't recommend using unknown code that does not even have a single comment explaining what it does. That's not a very good mark of quality.