lw = [0.1e6 1e6 10e6];

for lp = 1

    rng(9);

    %% A) Set Simulation Variables

    sir     = -18;
    delay   = 10; %mpi delay in meter

    fiblen = 0; %main link in km

    laser_linewidth =5e6;

    O = 18; %order of prbs
    N = 2^(O-1); %length of prbs
    [~,seed] = prbs(O,1); %initialize first seed of prbs

    % Modulation
    M = 4; %PAM-M
    bitpattern = zeros(N,log2(M));

    % Symbol Rate
    fsym = 112e9;

    % DAC Rate
    fdac = 120e9;

    % Simulation oversampling rate "k";
    kover = 16;

    % ADC Rate
    fadc = 256e9;

    % Simulation frequency in "analog domain"
    fsimu = kover * fdac ;



    %% B) CONSTRUCT ALL CLASSES %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

    digimod     = PAMmapper(M,0);

    pulseform   = Pulseformer("pulseform","rrc","fdac",fdac,"fsym",fsym,"pulselength",32,"rrcalpha",0.027);

    awg         = AWG('fdac',fdac,'kover',kover,'lpf_active',1,'f_cutoff',56e9,'lpf_type',filtertypes.gaussian,'bit_resolution',5.5);

    lp_laser    = Filter('filtdegree',1,"f_cutoff",50e9,"fsamp",fdac*kover,"filterType",filtertypes.bessel_inp);

    u_pi = 3.5;
    vbias = (0.5*u_pi)-u_pi;
    extmodlaser = EML("mode",eml_mode.im_cosinus,"power",5,"fsimu",fsimu,"lambda",1550,"bias",vbias,"u_pi",u_pi,"linewidth",laser_linewidth);

    fib         = Fiber("fsimu",fdac*kover,"fiber_length",fiblen,"alpha",0.2,"D",16,"lambda0",thz2nm(193.1),"gamma",0);

    reflectionpoint  = Amplifier("amp_mode","ideal_no_noise","gain_mode","gain","amplification_db",sir);
    reflectionprop   = Fiber("fsimu",fdac*kover,"fiber_length",delay/1000,"alpha",0.2,"D",16,"lambda0",1550,"gamma",0);

    opticatten  = Amplifier("amp_mode","ideal_no_noise","gain_mode","output_power","amplification_db",-8);

    phdiode     = Photodiode("fsimu",fdac*kover,"dark_current",2e-08,"responsivity",1,"temperature",20);

    lp_diode    = Filter('filtdegree',1,"f_cutoff",50e9,"fsamp",fdac*kover,"filterType",filtertypes.bessel_inp);

    scp         = Scope("fsimu",fdac*kover,"fadc",fadc,...
        "delay",0,"fixed_delay",0,"lpf_bw",113e9,"filtertype",filtertypes.butterworth,...
        "samplingdelay",0,"rand_samplingdelay",0,"freq_offset",0,"samp_jitter",0,...
        "adcresolution",6,"quantbuffer",0.1,'block_dc',1);

    eq          = EQ("K",2,"plottrain",0,"plotfinal",0,...
        "training_length",4096,"training_loops",2,...
        "Ne",[50,5,3],"Nb",[3,2,2],...
        "DCmu",0.05,"DDmu",[0.0004 0.0005 0.0006 0.0007 ],"DFEmu",0.005,"FFEmu",0.005,...
        "dd_loops",2,"epsilon",[10 100 1000 ],"M",2,...
        "thres",[0.005 0.004 0.0005 ],"l1act",0,"delay",0,"rho",0.0005,"ideal_dfe",0,"DB_aim",0);

    eq2 = EQ_silas("Ne",[30,0,0],"Nb",[3,0,0],"trainlength",4096,"mu_dc_dd",0.005,...
        "mu_dc_train",0.05,"mu_ffe_train",0.005,"mu_combined_dd",[0.0004 0.0006 0.0003 0.005],"ddloops",3,'dcmode',3);


    %% C) PROCESS TX %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

    % 1) PRBS Generation
    for i = 1:log2(M)
        [bitpattern(:,i),seed] = prbs(O,N,seed);
    end

    % 2 ) Build Inf. signal class
    bits = Informationsignal(bitpattern);

    % 3) Digi modulation -> PAM-M signal
    digimod_out = digimod.map(bits);

    % 4) Pulse shaping -> racos
    X = pulseform.process(digimod_out);

    % 5) AWG (lowpass, quantization, sample and hold)
    X = awg.process(X);

    % 6) Lowpass behavior of laser and hf-cable? why twice?
    X = lp_laser.process(X);
    X = lp_laser.process(X);

    % 7) Normalize signal
    X = X.normalize("mode","oneone");
    X.signal = X.signal .* 1.3800;


    %% D) PROCESS OPTICAL CHANNEL %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

    % 1) Laser; Modulation ->  OPTICAL DOMAIN
    [X,extmodlaser] = extmodlaser.process(X);

    % 2) Main fiber propagation
    X = fib.process(X);

    if delay ~= 0
    % 3) Reflection 
        % Reflection is just an attenuation
        R = reflectionpoint.process(X);
    
        % Propagate back and forth (actual fiber propagation)
        R = reflectionprop.process(R);
    
        % Delay the reflected signal
        [R,n] = R.delay("delay_meter",delay);
    
%         % Add together
%         col = cbrewer2('qual','Paired',8);
% 
%         xax = (1:X.length);% / fsimu * (physconst("LightSpeed")/1.4677);
%         xax_mtr = (1:X.length) / fsimu * (physconst("LightSpeed")/1.4677);
%         thresh = 0.7;
%         phaseX = phase(X.signal);
%         phaseR = phase(R.signal);
%         phasediff = wrapToPi(phaseX-phaseR);
%         [pos_high] = find(abs(phasediff)>thresh);
%         [pos_low] = find(abs(phasediff)<=thresh);
% 
%         figure()
%         subplot(3,1,1)
%         scatter(xax_mtr,wrapToPi(phaseX),4,'.','MarkerEdgeColor',col(4,:),'DisplayName','Phase of original Signal')
%         hold on
%         scatter(xax_mtr,wrapToPi(phaseR),4,'.','MarkerEdgeColor',col(7,:),'DisplayName','Phase of delayed Signal')
%         hold on
%         xline(delay,'LineWidth',4,'LineStyle','--','HandleVisibility','off')
%         lg = legend;
%         lg.Location = "southwest";
% 
%         subplot(3,1,2)
%         scatter(xax_mtr(pos_low),phasediff(pos_low),4,'.','MarkerEdgeColor',col(6,:),'DisplayName','Phase Difference')
%         hold on
%         scatter(xax_mtr(pos_high),phasediff(pos_high),4,'.','MarkerEdgeColor',col(4,:),'HandleVisibility','off')
%         xline(delay,'LineWidth',4,'LineStyle','--','HandleVisibility','off')
%         yline(thresh,'LineWidth',2,'LineStyle','-','HandleVisibility','off')
%         yline(-thresh,'LineWidth',2,'LineStyle','-','HandleVisibility','off')
%         lg = legend;
%         lg.Location = "southwest";

        X = X+R;

%         subplot(3,1,3)
%         scatter(xax_mtr(pos_low),abs(X.signal(pos_low).^2),4,'.','MarkerEdgeColor',col(6,:),'DisplayName','Constructive Interference');
%         hold on
%         scatter(xax_mtr(pos_high),abs(X.signal(pos_high).^2),4,'.','MarkerEdgeColor',col(4,:),'DisplayName','Destructive Interference');
%         xline(delay,'LineWidth',4,'LineStyle','--','HandleVisibility','off')
% 
%         lg = legend;
%         lg.Location = "southwest";

        X.signal = X.signal(n:end);
        R.signal = R.signal(n:end);

        
        disp(['SIR ',num2str(10*log10(X.power/R.power))]);

        % cut reference signal to correct length (nessecary due to MPI delay)
        digimod_out.signal = digimod_out.signal(round(n * fsym/fsimu) : end,:);

        bitpattern = bitpattern(round(n * fsym/fsimu):end,:);
    
    end


%         plot(angle(R.signal))
    
    % 4) Attenuation 
    X = opticatten.process(X);
   

    % 5) Photo Diode -> ELECTRICAL DOMAIN
    X = phdiode.process(X);
    X = lp_diode.process(X);


    %% E) PROCESS RX %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

    % 1) Oscilloscope (Sampling to f_adc; Quantization; Bandwidth Limitation)
    X = scp.process(X);

    % 2) Resample to 2x symbol rate
    X = X.resample("fs_out",2*fsym,"fs_in",fadc);

    % 3) Normalize
    Eq_in = X.normalize("mode","rms");

    % 4) Equalize

        % MPI reduction DC removal BEFORE EQ
        wl = 3000; % symbols
        Eq_in.signal = Eq_in.signal - 1/wl .* movsum( Eq_in.signal,[wl/2,wl/2]);

        % Equalize Signal
        [Eq_out]             = eq2.process(Eq_in,digimod_out);



    %% A1: MPI reduction DC removal
    wl = 1000; % symbols
    yk_dcsm = Eq_out;
    yk_dcsm.signal = Eq_out.signal - 1/wl .* movsum( Eq_out.signal,[wl/2,wl/2]);

    %% A2: MPI reduction Level wise error removal
    yk_lvsm = Eq_out;
    yk_lvlp = Eq_out;
    pre_decision_level_uni  = digimod.decide_pamlevel(Eq_out);
    pre_decision_level_bi   = ( pre_decision_level_uni*2-3 ) .* 1/sqrt(5);

    e = Eq_out.signal - pre_decision_level_bi;

    lp_mpi    = Filter('filtdegree',1,"f_cutoff",2e6,"fsamp",fsym,"filterType",filtertypes.bessel_inp);

    filtered = lp_mpi.process(e);

    wl = 30; % symbols
    smoothed = ( 1/wl .* movsum(e,[wl/2,wl/2])  );

    % remove interference
    for level = 0:3
        yk_lvsm.signal(pre_decision_level_uni==level) = yk_lvsm.signal(pre_decision_level_uni==level) - smoothed(pre_decision_level_uni==level);
        yk_lvlp.signal(pre_decision_level_uni==level) = yk_lvlp.signal(pre_decision_level_uni==level) - filtered(pre_decision_level_uni==level);
    end
   
    % Calc EVM

    evm_bm   = calc_evm(Eq_out.signal, pre_decision_level_bi);
    evm_dcsm = calc_evm(yk_dcsm.signal, pre_decision_level_bi);
    evm_lsm  = calc_evm(yk_lvsm.signal, pre_decision_level_bi);
    evm_llp  = calc_evm(yk_lvlp.signal, pre_decision_level_bi);

    %     figure(1);bar([evm_bm' evm_dcsm' evm_llp' evm_lsm']);ylim([0.01 0.1]);set(gca,'yscale','log');



    %% PROCESS RX %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

    % 1) Digi Demod
    d_bm = digimod.demap(Eq_out);
    d_dcsm = digimod.demap(yk_dcsm);
    d_lvsm = digimod.demap(yk_lvsm);
    d_lvlp = digimod.demap(yk_lvlp);

    % 2) BER
    dbit =  length(d_bm.signal)-length(bitpattern);

    [~,errors_bm,ber_bm,loc] = calc_ber(d_bm.signal(1:end-dbit,:)    ,bitpattern(1:end,:),"skip",0,"returnErrorLocation",1);
    [~,errors_dcsm,ber_dcsm] = calc_ber(d_dcsm.signal(1:end-dbit,:)  ,bitpattern(1:end,:),"skip",0,"returnErrorLocation",0);
    [~,errors_lvsm,ber_lvsm] = calc_ber(d_lvsm.signal(1:end-dbit,:)  ,bitpattern(1:end,:),"skip",0,"returnErrorLocation",0);
    [~,errors_lvlp,ber_lvlp] = calc_ber(d_lvlp.signal(1:end-dbit,:)  ,bitpattern(1:end,:),"skip",0,"returnErrorLocation",0);

    % Display BER
    disp(['BER benchmark: ', sprintf('%2E',ber_bm),   ' ERRORS: ' ,num2str(sum(errors_bm))]);
    disp(['BER dc smooth (A1): ', sprintf('%2E',ber_dcsm), ' ERRORS: ' ,num2str(sum(errors_dcsm))]);
    disp(['BER lv smooth (A2): ', sprintf('%2E',ber_lvsm), ' ERRORS: ' ,num2str(sum(errors_lvsm))]);
    disp(['BER lv lowpas: ', sprintf('%2E',ber_lvlp), ' ERRORS: ' ,num2str(sum(errors_lvlp))]);


    %% Generate some Plots

    if 1

        % SCATTER
        col = cbrewer2('Paired',8);

        xax = 1:Eq_out.length;

        figure(3)
        sgtitle('')

        subplot(1,3,1)
        hold on
        eq_decision  = digimod.decide_pamlevel(Eq_out);
        true_symbols = digimod.decide_pamlevel(digimod_out);

        xindices = 1:Eq_in.length;
        errorpos = find(loc~=0)*2;
        errorpos(errorpos>length(Eq_in.signal)) = length(Eq_in.signal);
        correct = find(loc==0)*2;
        correct(correct>length(Eq_in.signal)) = length(Eq_in.signal);
        scatter(xindices(correct),Eq_in.signal(correct),4,'.','MarkerEdgeColor',col(4,:),'DisplayName','After EQ');
        hold on
        scatter(xindices(errorpos),Eq_in.signal(errorpos),6,'x','MarkerEdgeColor',col(6,:),'DisplayName','Wrong Decision');
        hold off

        xlim([1, xindices(end)]);
        ylim([-3 3]);
        xlabel('Sampling Index')
        ylabel('Amplitude')
        a = legend;
        a.Location = "best";

        subplot(1,3,2)
        xindices = 1:Eq_out.length;
        scatter(xindices(loc==0),Eq_out.signal(loc==0),4,'.','MarkerEdgeColor',col(4,:),'DisplayName','After EQ');
        hold on
        scatter(xindices(loc~=0),Eq_out.signal(loc~=0),8,'x','MarkerEdgeColor',col(6,:),'DisplayName','Wrong Decision');
        hold off
        xlim([1, xax(end)]);
        ylim([-2 2]);
        xlabel('Sampling Index')
        ylabel('Amplitude')
        legend
        a = legend;
        a.Location = "best";
        hold off

        subplot(1,3,3)
        xindices = 1:yk_lvsm.length;
        scatter(xindices(loc==0),yk_lvsm.signal(loc==0),4,'.','MarkerEdgeColor',col(4,:),'DisplayName','After A2');
        hold on
        scatter(xindices(loc~=0),yk_lvsm.signal(loc~=0),8,'x','MarkerEdgeColor',col(6,:),'DisplayName','Wrong Decision');
        hold off
        xlim([1, xax(end)]);
        ylim([-2 2]);
        xlabel('Sampling Index')
        ylabel('Amplitude')
        legend
        a = legend;
        a.Location = "best";
        hold off


                % ERROR IN EQ
        figure(13)
        plot((eq2.error_log(1,:)),'DisplayName','First iteration DD mode','Linewidth',0.5);
        hold on; 
        for i = 1:size(eq2.error_log,1)
            plot((eq2.error_log(i,:)),'Linewidth',0.5);
        end
        loc(loc==0) = NaN;
        stem(loc.*mean((eq2.error_log(end,:))),'DisplayName','Error Positions')
        hold off

    end

    if 0
        col = cbrewer2('Paired',8);

        figure(11)
        clf

        subplot(2,1,1)
        hold on
        plot(digimod_out.signal(4150:4175),'DisplayName','Tx','Color',col(1,:),'LineWidth',3);
        plot(Eq_out.signal(4150:4175),'DisplayName','Rx after EQ','Color',col(6,:),'LineWidth',1);
        title('Modulated Sequence Zoom');
        legend
        hold off
        subplot(2,1,2)
        hold on
        stem(d_bm.signal(4150:4175,1),'DisplayName','Tx','Color',col(1,:),'LineStyle','-','LineWidth',5)
        stem(bitpattern(4150:4175,1)','DisplayName','Rx','Color',col(6,:),'LineStyle','--','LineWidth',2)
        title('Bitpattern Tx - Rx');
        legend
        hold off

    end
end