clc
clear?all;
N=3*10^5;??????????????????????%number?of?symbol
symbol_set=[1+1i;1-1i;1i-1;1i-1i]/sqrt（2）;???%set?of?symbol?to?be?transmitted
symbolset_size=4;
symbol_size=N/3;
Eb_No_Db=（0:25）;
nTx=2;??????????????????????????????%?number?of?transmitting?antenna
nRx=2;??????????????????????????????%?number?of?receiving?antenna
antennabits=[0;1];
Sym_to_bit=[0?0;0?1;1?0;1?1];

i=randi（[0?1]1N）?;????%?generating?stream?of?bits

x=vec2mat（i3）;??????????%?grouping?generated?bits?into?3

s=kron（symbol_setones（nRx1））;???%?grouping?symbols?into?matrix
s=repmat（s[1?nTx]）;
xTransmit=zeros（symbol_sizenTx）;?????????????????????????????????????????????????????????????
xDemod=zeros（symbol_size3）;??????????????????????????????????????????????????????????????????

antenna_symbol=zeros（N/31）;????
antenna_symbol（:1）=x（:1）+1;???????%?
antenna_symbol（:2）=symbol_set（bi2de（x（:2:3）‘left-msb‘）+1）?;???%Modulate

for?ii=1:length（Eb_No_Db）
????
????for?jj=1:symbol_size
???????
????????h=1/sqrt（2）*（randn（nRxnTx））+?1i*（randn（nRxnTx））;????%?rayleigh?channel
????????
????????n=1/sqrt（2）*（randn（nRx1））+1i*（randn（nRx1））;????????????%?noise
????????
????H=kron（ones（symbolset_size1）h）;??????
??????sD=?H.*s;
??????
????????????xTransmit（jjantenna_symbol（jj1））?=antenna_symbol（jj2）?;?????????????%?Assign?Symbol?and?Antenna?Index
????????????xTransmit2=kron（xTransmit（jj:）ones（nRx1））;
????????????
????????????y?=?sum（xTransmit2.*h2）?+10^（-Eb_No_Db（ii）/20）*n;
????????????
????????????y2=kron（ones（symbolset_size1）y）;??????????????????????????????????????????????????%?Copy?for?Symbol?set
????????????y2=repmat（y21nRx）;????????????????????????????????????????????????????????????%?Copy?for?Antenna
????????????y2=abs（y2-sD）;

????????????z=zeros（symbolset_sizenTx）;
????????????z（1:）=abs（sum（y2（1:2:）1））;
????????????z（2:）=abs（sum（y2（3:4:）1））;
????????????z（3:）=abs（sum（y2（5:6:）1））;
????????????z（4:）=abs（sum（y2（7:8:）1））;
????????????[v?r]=min（z）;
????????????[v?c]=min（v）;
????????????xDemod（jj1）=antennabits（c）;
????????????
????????????xDemod（jj2:3）=Sym_to_bit（r（c）:）;
??????
????end
????
????nErr（ii）=?size（find（i-reshape（xDemod‘1[]））2）;
end
simBER?=?nErr/N;


close?all
figure
semilogy（Eb_No_DbsimBER‘m.-‘‘linewidth‘2）;
axis（[0?20?10^-5?1]）
grid?on
legend（‘Sim?4QAM‘）;
xlabel（‘Eb/No?dB‘）
ylabel（‘Bit?Error?Rate‘）
title（‘Bit?Error?Prob?4QAM?2x2?（3?Bit）?with?SM?in?Rayleigh?Fading‘）

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

?????文件???????2498??2014-05-17?01:18??SM_4QAM_ML.m

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

?????????????????2498????????????????????1