i have written a code for BER v/s SNR calculation for AWGN channel with pilot insertion.why i m not getting feasible results

M=2;

N=64;

Np=4;

Nframes=1000;

D = round((M-1)*rand((N-Np),Nframes));

data=D';

data=data(:);

Mod=pskmod(D,M); % PSK modulation

Mod=Mod';

pilot=3+3j; % pilot value

pilotdata=zeros(1000,64); % initializing with zeroes

u=0;

%pilot insertion

for p=1:1000

for q=1:13:52

pilotdata(p,q)=pilot;

J=q+1:q+12;

k=q-u:q-u+11;

pilotdata(p,J)=Mod(p,k);

u=u+1;

end

u=0;

end

for p=1:1000

m=53:64;

n=49:60;

pilotdata(p,m)=Mod(p,n);

end

% ofdm modulation

ifft_data=ifft(pilotdata',64)';

%cyclic prefix insertion

for p=1:1000

m=65:80;

n=1:16;

ifft_data1(p,m)= ifft_data(p,n);

end

% channel

for snr=100

ofdm_sig=awgn(ifft_data1,snr,'measured'); % Adding white Gaussian Noise

end

% receiver

% removing cyclic extension

for p=1:1000

i=1:64;

rxed_sig(p,i)=ofdm_sig(p,i);

end

% FFT

ff_sig=fft(rxed_sig',64)';

% pilot synch

g=0;

for p=1:1000

for i=1:13:52

J=i+1:i+12;

k=i-g:i+11-g;

synch_sig(p,k)=ff_sig(p,J);

g=g+1;

end

g=0;

end

for p=1:1000

m=53:64;

n=49:60;

synch_sig(p,n)=ff_sig(p,m);

end

%demodulation

demod_sig=pskdemod(synch_sig,2);

demod_sig=demod_sig(:);

hErr=comm.ErrorRate;

errop=step(hErr,data,demod_sig);