function?output_frame?=?demodulation1（input_modu?index）
%?demodulation?for?IEEE802.11a
%?Input:????input_modu?complex?values?representing?constellation?points
%???????????index
%?Output:???output_frame?output?bit?stream?（data?unit?is?one?bit）
??
%?In?this?version?increase?the?quatilization?levels?into?8.
%?note:?Matlab?index?starts?from?1
guiyi=[1?sqrt（2）?sqrt（6）?sqrt（10）?sqrt（20）?sqrt（42）];
input_modu=input_modu*guiyi（index）;
Q_length=length（input_modu）;
Q_length=length（input_modu）;
QAM_input_I?=?real（input_modu）;
QAM_input_Q?=?imag（input_modu）;
output_frame?=?zeros（1length（input_modu）*index）;
switch?index
case?1
????BPSK_Demodu_I?=?[0?1];??????%f（m）=（m+1）/2?+?1?so?I=-1?--->?1?I=1?--->?2
????idx?=?find（QAM_input_I>1）;
????QAM_input_I（idx）?=?1;
????idx?=?find（QAM_input_I<-1）;
????QAM_input_I（idx）?=?-1;
????output_frame?=?BPSK_Demodu_I（round（（QAM_input_I+1）/2）?+?1）;
case?2
????QPSK_Demodu_IQ?=?[0?1];?????%f（m）=（m+1）/2?+?1?so?I=-1?--->?1?I=1?--->?2
????idx?=?find（QAM_input_I>1）;
????QAM_input_I（idx）?=?1;
????idx?=?find（QAM_input_I<-1）;
????QAM_input_I（idx）?=?-1;
????idx?=?find（QAM_input_Q>1）;
????QAM_input_Q（idx）?=?1;
????idx?=?find（QAM_input_Q<-1）;
????QAM_input_Q（idx）?=?-1;
????output_frame（1:2:end）?=?QPSK_Demodu_IQ（round（（QAM_input_I+1）/2）?+?1）;
????output_frame（2:2:end）?=?QPSK_Demodu_IQ（round（（QAM_input_Q+1）/2）?+?1）;
case?3
????mapping=[3+i?1+i?-3+i?-1+i?-3-i?-1-i?3-i?1-i];
????remapping=[0?0?0;0?0?1;0?1?0;0?1?1;1?0?0;1?0?1;1?1?0;1?1?1].‘;
????a=ones（18）;
????for?j=1:Q_length
??????b?=?mapping-input_modu（j）*a;
??????[gk?k1]=min（abs（b）.^2）;
??????output_frame（（1+（j-1）*3）:（3+（j-1）*3））=remapping（（1+3*（k1-1））:（3+3*（k1-1）））;
????end?
case?4
????QAM_16_Demodu_IQ?=?[0?1?3?2];???%f（m）=（m+3）/2?+?1?so?I=-3?--->?1?I=1?--->?3
????idx?=?find（QAM_input_I>3）;
????QAM_input_I（idx）?=?3;
????idx?=?find（QAM_input_I<-3）;
????QAM_input_I（idx）?=?-3;
????idx?=?find（QAM_input_Q>3）;
????QAM_input_Q（idx）?=?3;
????idx?=?find（QAM_input_Q<-3）;
????QAM_input_Q（idx）?=?-3;
????tmp?=?round（（QAM_input_I+3）/2）?+?1;
????output_frame（1:4:end）?=?bitget（QAM_16_Demodu_IQ（tmp）2）;
????output_frame（2:4:end）?=?bitget（QAM_16_Demodu_IQ（tmp）1）;
????tmp?=?round（（QAM_input_Q+3）/2）?+?1;
????output_frame（3:4:end）?=?bitget（QAM_16_Demodu_IQ（tmp）2）;
????output_frame（4:4:end）?=?bitget（QAM_16_Demodu_IQ（tmp）1）;
case?5
????mapping=[5+i?3+i?1+i?5+3*i?3+3*i?1+3*i?3+5*i?1+5*i?-5+i?-3+i?-1+i?-5+3*i?-3+3*i?-1+3*i?-3+5*i?-1+5*i?-5-i?-3-i?-1-i?-5-3*i?-3-3*i?-1-3*i?-3-5*i?-1-5*i?5-i?3-i?1-i?5-3*i?3-3*i?1-3*i?3-5*i?1-5*i];
????remapping=[0?0?0?0?0;0?0?0?0?1;0?0?0?1?0;0?0?0?1?1;0?0?1?0?0;0?0?1?0?1;0?0?1?1?0;0?0?1?1?1;
????????????????0?1?0?0?0;0?1?0?0?1;0?1?0?1?0;0?1?0?1?1;0?1?1?0?0;0?1?1?0?1;0?1?1?1?0;0?1?1?1?1;
????????????????1?0?0?0?0;1?0?0?0?1;1?0?0?1?0;1?0?0?1?1;1?0?1?0?0;1?0?1?0?1;1?0?1?1?0;1?0?1?1?1;
????????????????1?1?0?0?0;1?1?0?0?1;1?1?0?1?0;1?1?0?1?1;1?1?1?0?0;1?1?1?0?1;1?1?1?1?0;1?1?1?1?1].‘;
????a=ones（132）;

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

?????文件???????3985??2012-06-05?22:08??sphere?decoding?modulation?by?QAM\demodulation.m

?????文件???????1056??2012-06-05?22:08??sphere?decoding?modulation?by?QAM\mapping.m

?????文件???????2336??2012-06-05?22:08??sphere?decoding?modulation?by?QAM\modulation.asv

?????文件???????2376??2012-06-05?22:08??sphere?decoding?modulation?by?QAM\modulation.m

?????文件????????992??2012-08-09?16:37??sphere?decoding?modulation?by?QAM\ray_doppler.m

?????文件???????3165??2012-06-05?22:08??sphere?decoding?modulation?by?QAM\SD_16.asv

?????文件???????3239??2012-10-20?09:35??sphere?decoding?modulation?by?QAM\SD_16.m

?????文件???????3916??2012-08-11?19:31??sphere?decoding?modulation?by?QAM\sd_16qam.asv

?????文件???????3936??2012-08-11?19:33??sphere?decoding?modulation?by?QAM\sd_16qam.m

?????文件???????4224??2012-06-05?22:08??sphere?decoding?modulation?by?QAM\SD_256.asv

?????文件???????4415??2012-06-05?22:08??sphere?decoding?modulation?by?QAM\SD_256.m

?????文件???????3936??2012-06-05?22:08??sphere?decoding?modulation?by?QAM\sd_256qam.asv

?????文件???????3937??2012-06-05?22:08??sphere?decoding?modulation?by?QAM\sd_256qam.m

?????文件???????3823??2012-06-05?22:08??sphere?decoding?modulation?by?QAM\sd_2_16qam.asv

?????文件???????3818??2012-06-05?22:08??sphere?decoding?modulation?by?QAM\sd_2_16qam.m

?????文件???????3666??2012-06-05?22:08??sphere?decoding?modulation?by?QAM\SD_64.m

?????文件???????3786??2012-06-05?22:08??sphere?decoding?modulation?by?QAM\sd_64qam.asv

?????文件???????3936??2012-06-05?22:08??sphere?decoding?modulation?by?QAM\sd_64qam.m

?????文件??????10990??2012-08-31?10:16??sphere?decoding?modulation?by?QAM\SEA_det.m

?????目錄??????????0??2013-03-22?15:10??sphere?decoding?modulation?by?QAM

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????????????????71532????????????????????20