**3.1.1.6 Pilot insertion**

lendata=length(y); pilt=3+3j;

```
nofpits=4; 
k=l; 
for i=(l:13:52) 
pilt_datal(i)=pilt; 
for j=(i+l:i+l2); 
pilt_datalG)=y(k) ; 
k=k+l; 
end 
end 
pilt_datal=pilt_datal'; % size of pilt_data =52 
pilt_data(l :52)=pilt_datal(l :52); % upsizing to 64 
pilt_data(13:64)=pilt_datal(l :52); % upsizing to 64 
for i=l:52 
pilt_data(i+6)=pilt_datal(i); 
end 
3.8IFFT 
ifft_sig=ifft(pilt_data',64);
```
Fig. 5. OFDM Signal

#### **3.1.1.7 Adding cyclic extension**

cext\_data=zeros(80,1); cext\_data(l :16)=ifft\_sig( 49:64 ); for i=l:64

cext\_data(i+ 16)=ifft\_sig(i);

end

Fig. 6. OFDM Signal after Cyclic prefix

#### **3.1.1.8 Channel**

```
o=l; 
for snr=0:2:50 
ofdm_sig=awgn(cext_data,snr, 'measured' ); % Adding white Gaussian Noise
```
Fig. 7. Constellation ordering at receiver
