function[U,S,V] = svd_decompose_channel(Mt,Mr,h_f,N);
% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% 將信道按奇異值分解
% Mt  發送天線數
% Mr  接收天線數
% h_f MIMO沖擊響應 Mr行，Mt*L列，其中L是信道有效時間
% N   子載波數
% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

U = [];
S = [];
V = [];
for i = 1:N;
    [Utmp Stmp Vtmp] = svd(h_f(:,(i-1)*Mt+1:i*Mt));
    U = [U Utmp];
    V = [V Vtmp];
    S = [S Stmp];
end

S = sum(S,1);