%16QAM-OFDM?system;
clear?all;
clear?all;

N?=?1024;????????????????????????????????????????????????????????%the?total?number?of?all?subcarriers
Np?=?128;?????????????????????????????????????????????????????????%the?number?of?pilot?carriers
B?=?2e6;?????????????????????????????????????????????????????????%bandwidth?2MHz
T?=?1/B;
Ng?=?256;????????????????????????????????????????????????????????%the?length?of?Guard?Interval
Xp?=?3?+?1.0*j?;??????????????????????????????????????????????????????%pilot?value
t=?0;??%?erro?code?number

for?u?=?1:20?????????????????????????????????????????????%?run?20?times
%-------------------------------------Data?generator--------------------------------------------------
xr1?=?rand（1N-Np）;
Xre?=?（-3）?*?（xr1?????+?（0.5?<=?xr1?&?xr1?xr2?=?rand（1N-Np）;
Xim?=?（-3）?*?（xr2????+?（0.5?<=?xr2?&?xr2?X?=?complex（XreXim）;????????????????????????????????????????????%16QAM
%?Xre?=?（-1）?*?（xr1?%?xr2?=?rand（1N-Np）;
%?Xim?=?（-1）?*?（xr2%?X?=?complex（XreXim）;????????????????????????????????????????????%QPSK
%----------------------------------??insert?pilot?in?carriers????-------------------------------------
%?pilots?locate?at?8*i?+?3;
Xc?=?zeros（1N）;?????????????????????????????????????????????????%the?carrier?value
m?=?0;
for?i?=?1?:?N
????if（mod（i8）?==?3）
?????????Xc（i）?=?Xp;
?????????m?=?m?+?1;
????else
????????Xc（i）?=?X（i?-?m）;
????end
end
%----------------------------------OFDM?modulation-------------------------------------------------------
Ym?=?ifft（XcN）;
%----------------------------------Insert?GI??CP---------------------------------------------------------
Y?=?[Ym（769:N）Ym];
%----------------------------------pass?channel-----------------------------------------------------------
Yc?=?ray_channel（YT）;
%---------------------------------add?noice?-------------------------------------------------------------
SNR?=?40;
%?for?S=1:21
??%SNR=?10log10（Es/N0）
%?N0?=?var（Yc）/（10^（SNR/10））;
%?sgma?=?sqrt（N0/2）;
%?Yawgn=Yc+sgma*randn（1length（Yc））+sgma*randn（1length（Yc））*j;
Yawgn?=?awgn（YcSNR‘measured‘）;
%-------------------------------------------------------------------------------------------------------?????
%?----------------------------------------------OFDM?RECEIVER-------------------------------------------??
%----------------------------------------------OFDM?demodulation----------------------------------------
Yr?=?fft（YawgnN）;
%-----------------------------------------------Pilot?signal?Extraction---------------------------------
c?=?1;
for?i?=?3:8:N
????Yp（c）?=?Yr（i）;
????c?=?c?+?1;
end
%-----------------------------------?Pilot?signal?Estimation?with?LS?Algorithm?-------------------------???
Hp?=?Yp?./?Xp;

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

?????文件???????4558??2005-09-12?18:55??朱志敏\OFDM_LS_directly.m

?????文件????????657??2005-09-12?18:52??朱志敏\ray_channell.m

?????目錄??????????0??2006-02-24?19:53??朱志敏

-----------?---------??----------?-----??----

?????????????????5433????????????????????4