%OFDM?Channel?Estimation?based?on?Comb?Pilot
%IFFT_bin_length:?IFFT和FFT的點數
%carrier_count:?子載波個數
%bits_per_symbol:?每符號上的比特數
%symbols_per_carrier:?每楨的OFDM符號數
%Ｘ：欲發送的二進制比特流

clear?all;
clc;
IFFT_bin_length=128;%ifft長度
carrier_count=100;%子載波數
bits_per_symbol=2;%每符號比特數
symbols_per_carrier=12;%一楨符號數
LI=7?;?%導頻之間的間隔
Np=ceil（carrier_count/LI）+1;%16?導頻數加1的原因：使最后一列也是導頻

N_number=carrier_count*symbols_per_carrier*bits_per_symbol;%2400一禎比特數
carriers=1:carrier_count+Np;%116?子載波加導頻

GI=8;?????????????%?guard?interval?length
N_snr=40;??????????%?每比特信噪比
snr=8;?????????????%信噪比間隔
%------------------------------------------------------------
%?vector?initialization


X=zeros（1N_number）;%2400個bit
X1=[];
X2=[];
X3=[];
X4=[];
X5=[];
X6=[];
X7=[];
Y1=[];
Y2=[];
Y3=[];
Y4=[];
Y5=[];
Y6=[];
Y7=[];
XX=zeros（1N_number）;%2400
dif_bit=zeros（1N_number）;%2400
dif_bit1=zeros（1N_number）;%2400
dif_bit2=zeros（1N_number）;%2400
dif_bit3=zeros（1N_number）;%2400
X=randint（1N_number）;%產生二進制隨即序列（非0即1）2400
%--------------------------------------------------------
%QPSK調制：（1?1）->pi/4;（0?1）->3*pi/4;（0?0）->-3*pi/4;（10）->-pi/4;

s=（X.*2-1）/sqrt（2）;
sreal=s（1:2:N_number）;
simage=s（2:2:N_number）;
X1=sreal+j.*simage;%已調信號bit流0.7071?-?0.7071i???0.7071?-?0.7071i???0.7071?+?0.7071i。。。。。（1*1200）

%---------------------------------------------------------
%產生隨機導頻信號
%--------------------------------------------------------
train_sym=randint（12*symbols_per_carrier）;%1*24
t=（train_sym.*2-1）/sqrt（2）;
treal=t（1:2:2*symbols_per_carrier）;
timage=t（2:2:2*symbols_per_carrier）;
training_symbols1=treal+j.*timage;%?0.7071?-?0.7071i??-0.7071?-?0.7071i??-0.7071?-?0.7071i???1*12
training_symbols2=training_symbols1.‘;%12*1
training_symbols=repmat（training_symbols21Np）;%12*16?復制第一列變成16列

%disp（training_symbols）
pilot=1:LI+1:carrier_count+Np;%導頻插入位置序號1?????9????17????25????33????41????49????57????65????73????81????89????97???105??113
if?length（pilot）~=Np
????pilot=[pilotcarrier_count+Np];%最后一列變成導頻1?????9????17????25????33????41????49????57????65????73????81????89????97???105??113???116
end
%--------------------------------------------------------
%串并轉換
X2=reshape（X1carrier_countsymbols_per_carrier）.‘;%12*100，12個復信號符號，100列載波
%---------------------------------------------------------
%插入導頻
signal=1:carrier_count+Np;%1*116
signal（pilot）=[];%1*100
X3（:pilot）=training_symbols;%先放入16列導頻
X3（:signal）=X2;%再放入12*100，100列子載波，共12*116
%X3=cat（1training_symbolsX2）;
IFFT_modulation=zeros（symbols_per_carrierIFFT_bin_length）;%12*128
IFFT_modulation（:carriers）=X3;%116列后補12列全0子載波，12*128
%IFFT_modulation（:conjugate_carriers）=conj（X3）;
X4=ifft（IFFT_modulationIFFT_bin_length2）;%每個符號128點ifft
%X5=X4.‘;
%加保護間隔（循環前綴）
for?k=1:symbols_per_carrier;
???for?i=1:IFFT_bin_length;
??????X6（ki+GI）=X4（ki）;
???end
???for?i=1:GI;
??????X6（ki）=X4（ki+IFFT_bin_length-GI）;????
???end
end
%---------------------------------------------------------
%并串轉換
X7=reshape（X6.‘1symbols_per_carrier*（IFFT_bin_length+GI））;%12*136先轉置，再變成1*1632

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----

?????文件???????8721??2009-07-13?11:05??信道估計\1329783688561Pilot\88561Pilot.m

?????文件???????6049??2010-05-30?12:05??信道估計\43680525ofdm-2channelest\仿真程序\2.fig

?????文件???????5993??2010-05-30?12:05??信道估計\43680525ofdm-2channelest\仿真程序\3.fig

?????文件????????137??2010-05-28?18:03??信道估計\43680525ofdm-2channelest\仿真程序\add_noise.asv

?????文件????????150??2010-05-28?20:27??信道估計\43680525ofdm-2channelest\仿真程序\add_noise.m

?????文件???????1388??2010-05-30?10:55??信道估計\43680525ofdm-2channelest\仿真程序\calcu_coeff.asv

?????文件???????1860??2010-05-30?13:13??信道估計\43680525ofdm-2channelest\仿真程序\calcu_coeff.m

?????文件???????2066??2010-05-29?21:41??信道估計\43680525ofdm-2channelest\仿真程序\calcu_coeff1.m

?????文件???????1167??2010-05-29?20:57??信道估計\43680525ofdm-2channelest\仿真程序\calcu_corrupted.m

?????文件????????339??2010-05-29?21:10??信道估計\43680525ofdm-2channelest\仿真程序\calcu_org.m

?????文件???????2741??2010-05-29?21:39??信道估計\43680525ofdm-2channelest\仿真程序\channel_est_A1.m

?????文件???????4492??2010-05-29?21:39??信道估計\43680525ofdm-2channelest\仿真程序\channel_est_A2.m

?????文件???????2061??2010-05-30?11:50??信道估計\43680525ofdm-2channelest\仿真程序\channel_est_p1.asv

?????文件???????2167??2010-05-30?13:17??信道估計\43680525ofdm-2channelest\仿真程序\channel_est_p1.m

?????文件???????2449??2010-03-22?10:54??信道估計\43680525ofdm-2channelest\仿真程序\channel_est_p2.asv

?????文件???????2229??2010-05-30?13:17??信道估計\43680525ofdm-2channelest\仿真程序\channel_est_p2.m

?????文件???????2121??2010-05-30?11:05??信道估計\43680525ofdm-2channelest\仿真程序\main.asv

?????文件???????1810??2010-05-30?11:54??信道估計\43680525ofdm-2channelest\仿真程序\main.m

?????文件????????103??2010-05-28?18:19??信道估計\43680525ofdm-2channelest\仿真程序\QPSK_modulation.asv

?????文件????????330??2010-05-29?20:31??信道估計\43680525ofdm-2channelest\仿真程序\QPSK_modulation.m

?????文件?????????81??2010-05-29?20:34??信道估計\43680525ofdm-2channelest\仿真程序\simulation.m

?????文件???????1093??2004-03-11?11:02??信道估計\60653330MIMO-OFDM\程序\adaptive.m

?????文件???????1144??2004-03-12?09:53??信道估計\60653330MIMO-OFDM\程序\adaptive_power.m

?????文件????????909??2004-04-15?07:40??信道估計\60653330MIMO-OFDM\程序\adaptive_power1.m

?????文件???????1796??2004-06-11?11:32??信道估計\60653330MIMO-OFDM\程序\add_freqdomain_reponse.m

?????文件???????4388??2004-05-26?15:42??信道估計\60653330MIMO-OFDM\程序\add_training.m

?????文件???????6175??2004-05-26?09:47??信道估計\60653330MIMO-OFDM\程序\adpt_mod_para.m

?????文件????????437??2000-03-03?23:08??信道估計\60653330MIMO-OFDM\程序\bin_state.m

?????文件???????1273??2004-06-10?14:04??信道估計\60653330MIMO-OFDM\程序\BLAST_decode.m

?????文件?????107336??2005-01-12?11:29??信道估計\60653330MIMO-OFDM\程序\ce_txdiv.mat

............此處省略281個文件信息