function?[demod_data]?=?demod_msk（signal_outI_outQ_outfcsample_numberdata_lenRbShape_b）?????????
%?signal_out?msk?調制信號
%?I_out??????????同相支路信號
%?Q_out??????????正交支路信號
%?fc?????????????載波頻率???
%?sample_number??每個碼元采樣數
%?data_len???????碼元數據個數???????
%?Rb?????????????碼元速率
%?demod_data?????解調輸出

mult?=?fc/Rb;????%fc是載波頻率?
I_temp=I_out;???
Q_temp=Q_out;?

Fs=fc*sample_number;??????????
t=0:1/Fs:（data_len*Fs/Rb-1）/Fs;???????????????????????%fs?=?Rb*sample_number;
%信號接收帶通濾波
signal_mod1?=?signal_out;
%**************************************************************************?
?%--------------------------------------------------------------------------?
?%I?Q支路去載波?
%??N=300;?%?濾波器的階數
%??F=[0fc-1000fc+1000Fs/2]*2/Fs;?
%??A=[1100];?
%??lpf=firls（NFA）;????????????%FIR濾波器設計
%??[amp_lpfw]=freqz（lpf）;?
?lpf=Shape_b;
?N=length（Shape_b）-1;?%?濾波器的階數
?I_dem=signal_mod1.*cos（2*pi*fc*t）*2;??%解調開始
?I_dem=conv（I_demlpf）;?????%做卷積，就是進行濾波
?I_dem=I_dem（N/2+1:N/2+length（I_temp））;?????????%N為濾波器階數
?Q_dem=signal_mod1.*sin（2*pi*fc*t）*2;?
?Q_dem=conv（Q_demlpf）;?
?Q_dem=-Q_dem（N/2+1:N/2+length（I_temp））;?
?
?I_dem_out=I_dem;?
?Q_dem_out=Q_dem;?
%??end;?
?%**************************************************************************?
?
?%--------------------------------------------------------------------------?
?%差分解調?，詳細表達式見msk報告
?demod_data?=?zeros（1data_len）;?
?demod_data（1）?=?I_dem_out（1）;?
?for?i?=?2:data_len?
?demod_data（i）?=?Q_dem_out（i*sample_number*mult）*I_dem_out（（i-1）*sample_number*mult）?-?I_dem_out（i*sample_number*mult）*Q_dem_out（（i-1）*sample_number*mult）;?
?end?
?%**************************************************************************?
?
?%--------------------------------------------------------------------------?
%判決?
?demod_data?=?demod_data>0;?
?demod_data?=?2*demod_data-1;?
?%**************************************************************************?

end

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????目錄???????????0??2018-06-06?12:05??MSK調制解調器\
?????文件???????20099??2018-05-24?20:27??MSK調制解調器\1.fig
?????文件???????24889??2018-05-25?20:48??MSK調制解調器\demodcomp.fig
?????文件???????29534??2018-05-26?16:24??MSK調制解調器\demodcomp1.fig
?????文件???????26295??2018-05-29?08:51??MSK調制解調器\demodcomp1withk.fig
?????文件????????2056??2018-05-25?20:43??MSK調制解調器\demod_msk.m
?????文件?????????599??2015-10-15?23:45??MSK調制解調器\difference.m
?????文件????????3059??2018-05-24?20:58??MSK調制解調器\E6_7_MskModem.m
?????文件?????????272??2018-05-24?21:07??MSK調制解調器\filterm.m
?????文件?????????699??2018-05-29?08:46??MSK調制解調器\incodemod_msk1.asv
?????文件?????????698??2018-05-29?08:49??MSK調制解調器\incodemod_msk1.m
?????文件?????????741??2018-05-26?15:24??MSK調制解調器\incodemod_msk2.m
?????文件????????2291??2018-05-29?08:45??MSK調制解調器\incomod_msk.m
?????文件????????3332??2018-05-29?08:41??MSK調制解調器\main.asv
?????文件????????3332??2018-05-29?08:48??MSK調制解調器\main.m
?????文件????????2014??2015-10-26?23:35??MSK調制解調器\mod_msk.m
?????目錄???????????0??2018-06-06?12:05??MSK調制解調器\仿真結果\
?????文件??????232358??2017-12-05?19:47??MSK調制解調器\仿真結果\MSK功率譜.bmp
?????文件???????28676??2018-05-13?16:23??MSK調制解調器\仿真結果\MSK功率譜.emf
?????文件????????7209??2018-05-08?22:00??MSK調制解調器\仿真結果\MSK誤碼率.fig