ifft_cp_tx_blk.m

matlab编写的MIMO-OFDM仿真程序

function ofdm_symbol = ifft_cp_tx_blk(inp_symbol,num_subc,guard_interval)
%-----------------------------------------------------------
%每个传输模块的IFFT和循环前缀
%-------------------------
%输入： 
%   inp_symbol ----所有子载波的输入符号
%   num_subc ----子载波数
%   guard_interval ----OFDM符号的保护间隔
%输出： 
%   ofdm_symbol ----加入IFFT和保护前缀的OFDM符号
%----------------------------

ofdm_symbol = ifft(inp_symbol,num_subc);
if(guard_interval>length(ofdm_symbol))
    error('The guard interval is greater than the ofdm symbol duration');
end

%The guard symbol is the copy of the end of the ofdm symbol to the
%beginning of the ofdm symbol
guard_symbol = ofdm_symbol(end-guard_interval+1:end);

%Add the cyclic prefix to the ofdm symbol
ofdm_symbol = [guard_symbol ofdm_symbol];