clear all;close all;clc;  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Program to generate the parameter h values%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%h=zeros(4,32);h(1,2)=2;h(1,7:8)=1;h(1,9)=2;h(1,13:14)=2;h(1,15:16)=1;h(2,2)=3;h(2,3)=2;h(2,4)=3;h(2,6)=1;h(2,7)=3;h(2,9)=2;h(2,10)=1;h(2,11)=2;h(2,12)=3;h(2,13)=2;h(2,14:15)=3;h(3,4)=2;h(3,6)=2;h(3,7)=1;h(3,8)=3;h(3,9:10)=2;h(3,12:13)=2;h(3,15)=1;h(3,16)=3;h(4,2)=1;h(4,3)=2;h(4,4)=1;h(4,6:7)=3;h(4,8:9)=2;h(4,10)=3;h(4,11)=2;h(4,12)=1;h(4,13)=2;h(4,14)=1;h(4,15)=3;h(4,16)=2;h(1:4,17:32)=h(1:4,1:16);null_symbol_duration=2656;no_of_subcarriers_per_symbol=1536;load ('freq_interleaving_12june.dat');freq_deinterleaving_mod1 = reshape(freq_interleaving_12june,1,1536); %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Program to generate the Phase Reference Symbol%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% First af all generate the k', i and n arrays is neededfor k=1:1536    switch k    case 1          k_bis=1;i=0;n=1;    case 33        k_bis=33;i=1;n=2;    case 65        k_bis=65;i=2;n=0;    case 97        k_bis=97;        i=3;        n=1;    case 129        k_bis=129;        i=0;        n=3;    case 161        k_bis=161;        i=1;        n=2;    case 193        k_bis=193;        i=2;        n=2;    case 225        k_bis=225;        i=3;        n=3;    case 257        k_bis=257;        i=0;        n=2;    case 289        k_bis=289;        i=1;        n=1;    case 321        k_bis=321;        i=2;        n=2;    case 353        k_bis=353;        i=3;        n=3;    case 385        k_bis=385;        i=0;        n=1;    case 417        k_bis=417;        i=1;        n=2;    case 449        k_bis=449;        i=2;        n=3;    case 481        k_bis=481;        i=3;        n=3;    case 513        k_bis=513;        i=0;        n=2;    case 545        k_bis=545;        i=1;        n=2;    case 577        k_bis=577;        i=2;        n=2;    case 609        k_bis=609;        i=3;        n=1;    case 641        k_bis=641;        i=0;        n=1;    case 673        k_bis=673;        i=1;        n=3;    case 705        k_bis=705;        i=2;        n=1;    case 737        k_bis=737;        i=3;        n=2;    case 769        k_bis=769;        i=0;        n=3;    case 801        k_bis=801;        i=3;        n=1;    case 833        k_bis=833;        i=2;        n=1;    case 865        k_bis=865;        i=1;        n=1;    case 897        k_bis=897;        i=0;        n=2;    case 929        k_bis=929;        i=3;        n=2;    case 961        k_bis=961;        i=2;        n=1;    case 993        k_bis=993;        i=1;        n=0;    case 1025        k_bis=1025;        i=0;        n=2;    case 1057        k_bis=1057;        i=3;        n=2;    case 1089        k_bis=1089;        i=2;        n=3;    case 1121        k_bis=1121;        i=1;        n=3;    case 1153        k_bis=1153;        i=0;        n=0;    case 1185        k_bis=1185;        i=3;        n=2;    case 1217        k_bis=1217;        i=2;        n=1;    case 1249        k_bis=1249;        i=1;        n=3;    case 1281        k_bis=1281;        i=0;        n=3;    case 1313        k_bis=1313;        i=3;        n=3;    case 1345        k_bis=1345;        i=2;        n=3;    case 1377        k_bis=1377;        i=1;        n=0;    case 1409        k_bis=1409;        i=0;        n=3;    case 1441        k_bis=1441;        i=3;        n=0;    case 1473        k_bis=1473;        i=2;        n=1;    case 1505        k_bis=1505;        i=1;        n=1;    end% Now it's time to calculate the phase reference symbol!% First of all the phi(k) phase is needed, so the "h" parameter% has to be determinated.    phi(k)=(pi/2)*(h(i+1,k-k_bis+1)+n);    z(k)=exp(j*phi(k));    if abs(real(z(k)))<1        Phase_Reference(k)=j*imag(z(k));    else        Phase_Reference(k)=real(z(k));    endendphase_ref_beginning= Phase_Reference;% for m=-8:8%     for n=0:15%         r11_m(m+9,n+1)=phase_ref_beginning(1,n+1)*conj(phase_ref_beginning(1,mod(n+1+m+9,16)));%     end%     r1_m(1,m+9)=sum(r11_m(m+9,:));% endphase_ref_beginning=[phase_ref_beginning zeros(1,512)];temp=[phase_ref_beginning(769:1536) phase_ref_beginning(1537:2048) phase_ref_beginning(1:768)];phase_ref_beginning=temp;NO_OF_DATA_BITS=768;no_of_fibs_tx_frame=12;no_of_CIFs_tx_frame=4;punctured_data_bits=3072;Tx_carriers_ofdm_symbol=1536;freq_interleaved_bits=2048;useful_symbol_duration=2048;guard_interval=504;%%%%%%%%%%%%Determining auto-correlation of TX PRS%%%%%%   %Loading real time data; Assume start of null symbol is unknown           DAB_RX_Frame15=load('237_488MHz_IF2MHz_PAT1_80dB_1_updated_frame_cs4.dat');   %2552 samples per symbol; %2506 samples per symbol in the frame for core clock =system clock*4DAB_RX_Frame15=DAB_RX_Frame15.';    %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%    %%%%%%%%%%%%%%%%  Null Symbol detection-Coarse timing estimation    %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%nn1=length(DAB_RX_Frame15);nn2=mod(nn1,32);nn=nn1/32;%Number of blocksmm=1;for i=1:nn    energy(i)=0;    for ii=1:32        energy(i)=energy(i)+((DAB_RX_Frame15(mm)*DAB_RX_Frame15(mm))/2);        mm=mm+1;    endend%%%%%%%%%%%%%%%%Algo 2%%%%%%%%%%%%%%%%%%%start=0;low=0;threshold = 5000;count=0;for i=2:nn    if (i==3850)        iii=0;    end    if low==0        if (energy(i)<energy(i-1))            start=1;            low=1;            threshold=energy(i-1)/10;            startpos=i;        else            start=0;        end    else        if (energy(i)<=threshold  && (energy(i)<=energy(i-1) ||( abs(energy(i)-energy(i-1)) <5000)  ) )            start=start+1;            if ((count <=2) && (count > 0))                startpos=i;            end        else            if (start > 250)                count=count+1;%low=0;%startpos=0;                if (count > 3)                    start=0;low=0;startpos=0;                else                    start=start+1;                end            end                    end    end    if (start>=332)        null_symbol_stop=10624;        break;    endendif (startpos>=2)    if energy(startpos+1) > 500000        Null_start_64=startpos;