fft.m

用matlab写的FFT程序。简单易懂！

%********************************************************************第八路*************************************************************************%
n8=0:ts:tao-ts;
spt=ones(1,length(n8)); 
n=0:ts:T_frame-ts;
s88=[spt, zeros(1,(T_frame/ts-length(spt)))];
s8=10*cos(2*pi*fo*(n-7*T_frame)-pha+pha8);
signal_8=s88.*s8;

n=0:ts:T_frame-ts;
t_mobj=2*r/c;              % 动目标位置
echo_mobj8=[zeros(1,t_mobj/ts),spt,zeros(1,(T_frame-t_mobj)/ts-length(spt))];
s_doppler8=10*cos(2*pi*(fo+fd)*(n-7*T_frame)-pha+pha8);
r8=s_doppler8.*echo_mobj8;
s_echo88=awgn(r8,20);                      %加了白噪声的回波信号
s_echo_8=s_echo88+s_echo_clutter;

%%%%%%发射信号8正交解调 %%%%%%
t_i8=local_oscillator_i.*signal_8;           % I路解调
t_q8=local_oscillator_q.*signal_8;        % Q路解调

b=fir1(20,0.2);
tran_i8=filter(b,1,t_i8);
tran_q8=filter(b,1,t_q8);

tran_8=tran_i8+i*tran_q8;   %发射复信号8

%%%%%%%%%回波信号8正交解调%%%%%%%%%%%      
s_echo_i8=local_oscillator_i.*s_echo_8;           % I路解调
s_echo_q8=local_oscillator_q.*s_echo_8;        % Q路解调
echo_i8=filter(b,1,s_echo_i8);
echo_q8=filter(b,1,s_echo_q8);

echo_8=echo_i8+i*echo_q8;   %回波复信号8

tran_8_cn=conj(tran_8);
return_8=conv(tran_8_cn,echo_8);

%********************************************************************第九路*************************************************************************%
n9=0:ts:tao-ts;
spt=ones(1,length(n9)); 
n=0:ts:T_frame-ts;
s99=[spt, zeros(1,(T_frame/ts-length(spt)))];
s9=10*cos(2*pi*fo*(n-8*T_frame)-pha+pha9);
signal_9=s99.*s9;

n=0:ts:T_frame-ts;
t_mobj=2*r/c;              % 动目标位置
echo_mobj9=[zeros(1,t_mobj/ts),spt,zeros(1,(T_frame-t_mobj)/ts-length(spt))];
s_doppler9=10*cos(2*pi*(fo+fd)*(n-8*T_frame)-pha+pha9);
r9=s_doppler9.*echo_mobj9;
s_echo99=awgn(r9,20);                      %加了白噪声的回波信号
s_echo_9=s_echo99+s_echo_clutter;

%%%%%%发射信号9正交解调 %%%%%%
t_i9=local_oscillator_i.*signal_9;           % I路解调
t_q9=local_oscillator_q.*signal_9;        % Q路解调

b=fir1(20,0.2);
tran_i9=filter(b,1,t_i9);
tran_q9=filter(b,1,t_q9);

tran_9=tran_i9+i*tran_q9;   %发射复信号9

%%%%%%%%%回波信号9正交解调%%%%%%%%%%%      
s_echo_i9=local_oscillator_i.*s_echo_9;           % I路解调
s_echo_q9=local_oscillator_q.*s_echo_9;        % Q路解调
echo_i9=filter(b,1,s_echo_i9);
echo_q9=filter(b,1,s_echo_q9);

echo_9=echo_i9+i*echo_q9;   %回波复信号9

tran_9_cn=conj(tran_9);
return_9=conv(tran_9_cn,echo_9);

%********************************************************************第10路*************************************************************************%
n1=0:ts:tao-ts;
spt=ones(1,length(n1)); 
n=0:ts:T_frame-ts;
s11=[spt, zeros(1,(T_frame/ts-length(spt)))];
s10=10*cos(2*pi*fo*(n-9*T_frame)-pha+pha10);
signal_10=s11.*s10;
 
n=0:ts:T_frame-ts;
t_mobj=2*r/c;              % 动目标位置
echo_mobj=[zeros(1,t_mobj/ts),spt,zeros(1,(T_frame-t_mobj)/ts-length(spt))];
s_doppler10=10*cos(2*pi*(fo+fd)*(n-9*T_frame)-pha+pha10);
r10=s_doppler10.*echo_mobj;
s_echo110=awgn(r10,20);                      %加了白噪声的回波信号
s_echo_10=s_echo110+s_echo_clutter;
 
%%%%%%发射信号1正交解调 %%%%%%
t_i10=local_oscillator_i.*signal_10;           % I路解调
t_q10=local_oscillator_q.*signal_10;        % Q路解调

b=fir1(20,0.2);
tran_i10=filter(b,1,t_i10);
tran_q10=filter(b,1,t_q10);

tran_10=tran_i10+i*tran_q10;   %发射复信号1

%%%%%%%%%回波信号1正交解调%%%%%%%%%%%      

s_echo_i10=local_oscillator_i.*s_echo_10;           % I路解调
s_echo_q10=local_oscillator_q.*s_echo_10;        % Q路解调
echo_i10=filter(b,1,s_echo_i10);
echo_q10=filter(b,1,s_echo_q10);

echo_10=echo_i10+i*echo_q10;   %回波复信号1

tran_10_cn=conj(tran_10);
return_10=conv(tran_10_cn,echo_10);
%********************************************************************第11路*************************************************************************%
n1=0:ts:tao-ts;
spt=ones(1,length(n1)); 
n=0:ts:T_frame-ts;
s11=[spt, zeros(1,(T_frame/ts-length(spt)))];
s11=10*cos(2*pi*fo*(n-10*T_frame)-pha+pha11);
signal_11=s11.*s11;
 
n=0:ts:T_frame-ts;
t_mobj=2*r/c;              % 动目标位置
echo_mobj=[zeros(1,t_mobj/ts),spt,zeros(1,(T_frame-t_mobj)/ts-length(spt))];
s_doppler11=10*cos(2*pi*(fo+fd)*(n-10*T_frame)-pha+pha11);
r11=s_doppler11.*echo_mobj;
s_echo111=awgn(r11,20);                      %加了白噪声的回波信号
s_echo_11=s_echo111+s_echo_clutter;
 
%%%%%%发射信号1正交解调 %%%%%%
t_i11=local_oscillator_i.*signal_11;           % I路解调
t_q11=local_oscillator_q.*signal_11;        % Q路解调

b=fir1(20,0.2);
tran_i11=filter(b,1,t_i11);
tran_q11=filter(b,1,t_q11);

tran_11=tran_i11+i*tran_q11;   %发射复信号1

%%%%%%%%%回波信号1正交解调%%%%%%%%%%%      

s_echo_i11=local_oscillator_i.*s_echo_11;           % I路解调
s_echo_q11=local_oscillator_q.*s_echo_11;        % Q路解调
echo_i11=filter(b,1,s_echo_i11);
echo_q11=filter(b,1,s_echo_q11);

echo_11=echo_i11+i*echo_q11;   %回波复信号1

tran_11_cn=conj(tran_11);
return_11=conv(tran_11_cn,echo_11);
%********************************************************************第12路*************************************************************************%
n1=0:ts:tao-ts;
spt=ones(1,length(n1)); 
n=0:ts:T_frame-ts;
s11=[spt, zeros(1,(T_frame/ts-length(spt)))];
s12=10*cos(2*pi*fo*(n-11*T_frame)-pha+pha12);
signal_12=s11.*s12;
 
n=0:ts:T_frame-ts;
t_mobj=2*r/c;              % 动目标位置
echo_mobj=[zeros(1,t_mobj/ts),spt,zeros(1,(T_frame-t_mobj)/ts-length(spt))];
s_doppler12=10*cos(2*pi*(fo+fd)*(n-11*T_frame)-pha+pha12);
r12=s_doppler12.*echo_mobj;
s_echo112=awgn(r12,20);                      %加了白噪声的回波信号
s_echo_12=s_echo112+s_echo_clutter;
 
%%%%%%发射信号1正交解调 %%%%%%
t_i12=local_oscillator_i.*signal_12;           % I路解调
t_q12=local_oscillator_q.*signal_12;        % Q路解调

b=fir1(20,0.2);
tran_i12=filter(b,1,t_i12);
tran_q12=filter(b,1,t_q12);

tran_12=tran_i12+i*tran_q12;   %发射复信号1

%%%%%%%%%回波信号1正交解调%%%%%%%%%%%      

s_echo_i12=local_oscillator_i.*s_echo_12;           % I路解调
s_echo_q12=local_oscillator_q.*s_echo_12;        % Q路解调
echo_i12=filter(b,1,s_echo_i12);
echo_q12=filter(b,1,s_echo_q12);

echo_12=echo_i12+i*echo_q12;   %回波复信号1

tran_12_cn=conj(tran_12);
return_12=conv(tran_12_cn,echo_12);
%********************************************************************第13路*************************************************************************%
n1=0:ts:tao-ts;
spt=ones(1,length(n1)); 
n=0:ts:T_frame-ts;
s11=[spt, zeros(1,(T_frame/ts-length(spt)))];
s13=10*cos(2*pi*fo*(n-12*T_frame)-pha+pha13);
signal_13=s11.*s13;
 
n=0:ts:T_frame-ts;
t_mobj=2*r/c;              % 动目标位置
echo_mobj=[zeros(1,t_mobj/ts),spt,zeros(1,(T_frame-t_mobj)/ts-length(spt))];
s_doppler13=10*cos(2*pi*(fo+fd)*(n-12*T_frame)-pha+pha13);
r13=s_doppler13.*echo_mobj;
s_echo113=awgn(r13,20);                      %加了白噪声的回波信号
s_echo_13=s_echo113+s_echo_clutter;
 
%%%%%%发射信号1正交解调 %%%%%%
t_i13=local_oscillator_i.*signal_13;           % I路解调
t_q13=local_oscillator_q.*signal_13;        % Q路解调

b=fir1(20,0.2);
tran_i13=filter(b,1,t_i13);
tran_q13=filter(b,1,t_q13);

tran_13=tran_i13+i*tran_q13;   %发射复信号1

%%%%%%%%%回波信号1正交解调%%%%%%%%%%%      

s_echo_i13=local_oscillator_i.*s_echo_13;           % I路解调
s_echo_q13=local_oscillator_q.*s_echo_13;        % Q路解调
echo_i13=filter(b,1,s_echo_i13);
echo_q13=filter(b,1,s_echo_q13);

echo_13=echo_i13+i*echo_q13;   %回波复信号1

tran_13_cn=conj(tran_13);
return_13=conv(tran_13_cn,echo_13);
%********************************************************************第14路*************************************************************************%
n1=0:ts:tao-ts;
spt=ones(1,length(n1)); 
n=0:ts:T_frame-ts;
s11=[spt, zeros(1,(T_frame/ts-length(spt)))];
s14=10*cos(2*pi*fo*(n-13*T_frame)-pha+pha14);
signal_14=s11.*s14;
 
n=0:ts:T_frame-ts;
t_mobj=2*r/c;              % 动目标位置
echo_mobj=[zeros(1,t_mobj/ts),spt,zeros(1,(T_frame-t_mobj)/ts-length(spt))];
s_doppler14=10*cos(2*pi*(fo+fd)*(n-13*T_frame)-pha+pha14);
r14=s_doppler14.*echo_mobj;
s_echo114=awgn(r14,20);                      %加了白噪声的回波信号
s_echo_14=s_echo114+s_echo_clutter;
 
%%%%%%发射信号1正交解调 %%%%%%
t_i14=local_oscillator_i.*signal_14;           % I路解调
t_q14=local_oscillator_q.*signal_14;        % Q路解调

b=fir1(20,0.2);
tran_i14=filter(b,1,t_i14);
tran_q14=filter(b,1,t_q14);

tran_14=tran_i14+i*tran_q14;   %发射复信号1

%%%%%%%%%回波信号1正交解调%%%%%%%%%%%      

s_echo_i14=local_oscillator_i.*s_echo_14;           % I路解调
s_echo_q14=local_oscillator_q.*s_echo_14;        % Q路解调
echo_i14=filter(b,1,s_echo_i14);
echo_q14=filter(b,1,s_echo_q14);

echo_14=echo_i14+i*echo_q14;   %回波复信号1

tran_14_cn=conj(tran_14);
return_14=conv(tran_14_cn,echo_14);
%********************************************************************第15路*************************************************************************%
n1=0:ts:tao-ts;
spt=ones(1,length(n1)); 
n=0:ts:T_frame-ts;
s11=[spt, zeros(1,(T_frame/ts-length(spt)))];
s15=10*cos(2*pi*fo*(n-14*T_frame)-pha+pha15);
signal_15=s11.*s15;
 
n=0:ts:T_frame-ts;
t_mobj=2*r/c;              % 动目标位置
echo_mobj=[zeros(1,t_mobj/ts),spt,zeros(1,(T_frame-t_mobj)/ts-length(spt))];
s_doppler15=10*cos(2*pi*(fo+fd)*(n-14*T_frame)-pha+pha15);
r15=s_doppler15.*echo_mobj;
s_echo115=awgn(r15,20);                      %加了白噪声的回波信号
s_echo_15=s_echo115+s_echo_clutter;
 
%%%%%%发射信号1正交解调 %%%%%%
t_i15=local_oscillator_i.*signal_15;           % I路解调
t_q15=local_oscillator_q.*signal_15;        % Q路解调

b=fir1(20,0.2);
tran_i15=filter(b,1,t_i15);
tran_q15=filter(b,1,t_q15);

tran_15=tran_i15+i*tran_q15;   %发射复信号1

%%%%%%%%%回波信号1正交解调%%%%%%%%%%%      

s_echo_i15=local_oscillator_i.*s_echo_15;           % I路解调
s_echo_q15=local_oscillator_q.*s_echo_15;        % Q路解调
echo_i15=filter(b,1,s_echo_i15);
echo_q15=filter(b,1,s_echo_q15);

echo_15=echo_i15+i*echo_q15;   %回波复信号1

tran_15_cn=conj(tran_15);
return_15=conv(tran_15_cn,echo_15);
%********************************************************************第16路*************************************************************************%
n1=0:ts:tao-ts;
spt=ones(1,length(n1)); 
n=0:ts:T_frame-ts;
s11=[spt, zeros(1,(T_frame/ts-length(spt)))];
s16=10*cos(2*pi*fo*(n-15*T_frame)-pha+pha16);
signal_16=s11.*s16;
 
n=0:ts:T_frame-ts;
t_mobj=2*r/c;              % 动目标位置
echo_mobj=[zeros(1,t_mobj/ts),spt,zeros(1,(T_frame-t_mobj)/ts-length(spt))];
s_doppler16=10*cos(2*pi*(fo+fd)*(n-15*T_frame)-pha+pha16);
r16=s_doppler16.*echo_mobj;
s_echo116=awgn(r16,20);                      %加了白噪声的回波信号
s_echo_16=s_echo116+s_echo_clutter;
 
%%%%%%发射信号1正交解调 %%%%%%
t_i16=local_oscillator_i.*signal_16;           % I路解调
t_q16=local_oscillator_q.*signal_16;        % Q路解调

b=fir1(20,0.2);
tran_i16=filter(b,1,t_i16);
tran_q16=filter(b,1,t_q16);

tran_16=tran_i16+i*tran_q16;   %发射复信号1

%%%%%%%%%回波信号1正交解调%%%%%%%%%%%      

s_echo_i16=local_oscillator_i.*s_echo_16;           % I路解调
s_echo_q16=local_oscillator_q.*s_echo_16;        % Q路解调
echo_i16=filter(b,1,s_echo_i16);
echo_q16=filter(b,1,s_echo_q16);

echo_16=echo_i16+i*echo_q16;   %回波复信号1

tran_16_cn=conj(tran_16);
return_16=conv(tran_16_cn,echo_16);
%********************************************************************第17路*************************************************************************%
n1=0:ts:tao-ts;
spt=ones(1,length(n1)); 
n=0:ts:T_frame-ts;
s11=[spt, zeros(1,(T_frame/ts-length(spt)))];
s17=10*cos(2*pi*fo*(n-16*T_frame)-pha+pha17);
signal_17=s11.*s17;
 
n=0:ts:T_frame-ts;
t_mobj=2*r/c;              % 动目标位置
echo_mobj=[zeros(1,t_mobj/ts),spt,zeros(1,(T_frame-t_mobj)/ts-length(spt))];
s_doppler17=10*cos(2*pi*(fo+fd)*(n-16*T_frame)-pha+pha17);
r17=s_doppler17.*echo_mobj;
s_echo117=awgn(r17,20);                      %加了白噪声的回波信号
s_echo_17=s_echo117+s_echo_clutter;
 
%%%%%%发射信号1正交解调 %%%%%%
t_i17=local_oscillator_i.*signal_17;           % I路解调
t_q17=local_oscillator_q.*signal_17;        % Q路解调

b=fir1(20,0.2);
tran_i17=filter(b,1,t_i17);
tran_q17=filter(b,1,t_q17);