MATLAB实现OFDM通信系统仿真与QAM调制关键代码

echo  off;clear all;close all;clc;
fprintf( 'OFDM·ÂÕæ\n') ;
tic

% --------------------------------------------- %
%                   ²ÎÊý¶¨Òå                     %
% --------------------------------------------- %
% Initialize the parameters
NumLoop = 100;
NumSubc = 128;
NumCP = 8;
SyncDelay = 0;
%-----------------------------------------------
% ×ÓÔز¨Êý            128
% λÊý/ ·ûºÅ          2
% ·ûºÅÊý/ Ôز¨        100
% ѵÁ··ûºÅÊý          0
% Ñ­»·Ç°×º³¤¶È        8   (1/16)*T
% µ÷ÖÆ·½Ê½            4-QAM
% ¶à¾¶ÐŵÀÊý          3 
%IFFT Size           128 
% ÐŵÀ×î´óʱÑÓ        2
%-----------------------------------------------

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%                   QAM MODULATION              %
% --------------------------------------------- %
% Generate the random binary stream for transmit test
BitsTx = floor(rand(1,NumLoop*NumSubc)*2);

% Modulate (Generates QAM symbols)
% input: BitsTx(1,NumLoop*NumSubc); output:SymQAM(NumLoop,NumSubc/2)
SymQAMtmp = reshape(BitsTx,2,NumLoop*NumSubc/2).';
SymQAMtmptmp = bi2de(SymQAMtmp,2,'left-msb');
%--------------------------------------------------------------------------
% º¯Êý˵Ã÷£º
% bin2dec(binarystr) interprets the binary string binarystr and returns the equivalent decimal number.
% bi2deÊÇ°ÑÁÐÏòÁ¿µÄÿһ¸öÔªËض¼ÓÉ2½øÖƱäΪ10½øÖÆ
% D = BI2DE(...,MSBFLAG) uses MSBFLAG to determine the input orientation.
% MSBFLAG has two possible values, 'right-msb' and 'left-msb'.  Giving a 'right-msb' MSBFLAG does not change the function's default behavior.
% Giving a 'left-msb' MSBFLAG flips the input orientation such that the
% MSB is on the left.
% D = BI2DE(...,P) converts a base P vector to a decimal value.
% Examples:
%>> B = [0 0 1 1; 1 0 1 0];
%>> T = [0 1 1; 2 1 0]; 
% >> D = bi2de(B)     >> D = bi2de(B,'left-msb')     >> D = bi2de(T,3)
%    D =                 D =                            D =
% %         12                   3                            12
% %          5                  10                              5
%--------------------------------------------------------------------------
% QAM modulation 
% 00->-1-i,01->-1+i,10->1-i,11->1+i
% ÀûÓòé±í·¨½øÐÐQAMÐÇ×ùÓ³Éä
QAMTable = [-1-i -1+i 1-i 1+i];
SymQAM = QAMTable(SymQAMtmptmp+1);

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                  IFFT                        
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