create_channel.m

mimoofdm系统自适应功率分配算法

function [H, H_f]=create_channel(Mt, Mr, A, N);
% function [H, H_f]=create_channel(Mt, Mr, A, N);
%
%   A - vector containing the power-delay profile (real values)
%   Mt - number of Tx antennas
%   Mr - number of Rx antennas
%   N - number of vector symbols to be sent in a single OFDM symbol Tx
%       ie: N MIMO transmissions in one OFDM symbol

% This is for Rayleigh frequency-selective fading, which assumes complex
% Gaussian matrix elements with in-phase and quadrature components independent.
% Assume iid matrix channel elements, and further, independent channel taps

% define the channel taps
A_length=length(A);
H_int = 1/sqrt(2)*(randn(Mr*A_length,Mt) + j*randn(Mr*A_length,Mt));

H_int2=[];
for i = 1:A_length
    H_int2 = [ H_int2;sqrt(A(i))*H_int((i-1)*Mr+1:i*Mr,:)];
   % H_int2 = sqrt(A(1:A_length))*H_int((0:A_length-1)*Mr+1:(1:A_length)*Mr,:);
   % H_int2=transpose(H_int2);
end

%%h_f = fft(H_int2',64);原来注释
%%H = H_int2';

H_int2 = [H_int2;zeros((N-A_length)*Mr,Mt)];

H_f = zeros(Mr,Mt*(N-16));
for i = 1:Mt
    for ir = 1:Mr
        h_f = fft(H_int2(ir:Mr:(N-16-1)*Mr+ir,i));
        for k = 1:(N-16)
            H_f(ir,i+(k-1)*Mt) = h_f(k);
            %H_f(ir,(0:N-17)*Mt+i) = h_f(1:N-16);
        end
    end
end

H=[H_int2];
for i = 1:N-1
    H=[H,[zeros(Mr*i,Mt);H_int2(1:(N-i)*Mr,:)]];
   % H=[zeros(Mr*(1:N-1),Mt);H_int2(1:(N-(1:N-1))*Mr,:)];
end