%%% Run parameters % TX % --- FIRST LINE: evaluate settings located beside this script --- run(fullfile(fileparts(mfilename('fullpath')),'WDM_settings.m')); s.num_realiz = 2; s.wavelengthplan = calcWavelengthPlan(16,400e9,1310); % wavelengthplan = [1295,1305,1315,1325]; link_length = 1; s.pmd = 0.1; s.gamma = 0.0023; s.M = 4; m = floor(log2(s.M)*10)/10; fsym = 112e9; fdac = 2*fsym; fadc = 120000000000; s.random_key = 100; % Laser / s.Modulator vbias_rel = 0.5; u_pi = 4.6; vbias = -vbias_rel*u_pi; laser_linewidth = 0e6; % EQ SETTINGS vnle_order1 = 50; vnle_order2 = 3; vnle_order3 = 3; vnle_order=[vnle_order1,vnle_order2,vnle_order3]; dfe_order = [0 0 0]; len_tr = 4096*2; mu_ffe1 = 0.0001; mu_ffe2 = 0.0008; mu_ffe3 = 0.001; mu_dc = 0.005; % mu_dc = 0; mu_ffe = [mu_ffe1 mu_ffe3 mu_ffe3]; mu_dfe = 0.0004; %DB Stuff db_precode = 0; db_encode = 0; duob_mode = db_mode.no_db; apply_pulsef = 0; rcalpha = 0.05; Pform = Pulseformer("fsym",fsym,"fdac",4*fsym,"pulse","rc","pulselength",16,"alpha",rcalpha); N = numel(s.wavelengthplan); f_plan = physconst('lightspeed')./(s.wavelengthplan.*1e-9); margin = 25e12; % some THz left and right f_span = (max(f_plan)+margin)-(min(f_plan)-margin); f_nyq = f_span/2; kover = 4; upsample_required = f_nyq./(fdac*kover/2); upsample_pow = 2^nextpow2(upsample_required); upsample_ceil = ceil(upsample_required); s.f_opt = fdac*kover*upsample_pow; s.f_opt_nyq = s.f_opt/2; signal_cell = {}; Symbols = {}; Tx_bits = {}; s.rop = -12:0.75:-0.75; output_ffe = cell(length(s.wavelengthplan),length(s.rop),s.num_realiz); output_vnle = cell(length(s.wavelengthplan),length(s.rop),s.num_realiz); output_mlse = cell(length(s.wavelengthplan),length(s.rop),s.num_realiz); output_dbt = cell(length(s.wavelengthplan),length(s.rop),s.num_realiz); s.p = "pair"; switch s.p case "co" pol_rot = 100.*ones(1,length(s.wavelengthplan)); case "pair" pol_rot = repmat([100,100,0,0],1,length(s.wavelengthplan)/4); case "alt" pol_rot = repmat([100,0,100,0],1,length(s.wavelengthplan)/4); end for realiz = 1:s.num_realiz parfor l = 1:N [Digi_sig,Symbols{l},Tx_bits{l}] = PAMsource(... "fsym",fsym,"M",s.M,"order",18,"useprbs",0,... "fs_out",fdac,... "applyclipping",0,"clipfactor",1.5,... "applypulseform",apply_pulsef,"pulseformer",Pform,... "randkey",s.random_key+l+realiz,... "db_precode",db_precode,"db_encode",db_encode,... "mrds_code",0,"mrds_blocklength",512,"duobinary_mode",duob_mode).process(); % Digi_sig.spectrum("fignum",101,"displayname",'bla','normalizeTo0dB',0,'lambda0_nm',1310,'useWavelengthAxis',0); Lp_awg = Filter('filtdegree',3,"f_cutoff",56e9,"fs",fdac*kover,"filterType",filtertypes.gaussian,"active",true); El_sig = AWG("fdac",fdac,"f_cutoff",fsym,"lpf_active",1,"kover",kover,"bit_resolution",6,"upsampling_method","samplehold","precomp_sinc_rolloff",0,"H_lpf",Lp_awg,"dac_max",0.6,"dac_min",-0.6).process(Digi_sig); % El_sig = s.M8199B("kover",kover).process(Digi_sig); % El_sig.spectrum("fignum",101,"displayname",'bla','normalizeTo0dB',0,'lambda0_nm',1310,'useWavelengthAxis',0); %%%%% Electrical Driver Amplifier %%%%%% El_sig = El_sig.normalize("mode","oneone"); El_sig = El_sig .* u_pi .* 0.5; % El_sig = El_sig.setPower(1,"dBm"); % figure;histogram(El_sig.signal); %%%%% s.MODULATE E/O CONVERSION %%%%% Eml_out = EML("mode",eml_mode.im_cosinus,"power",3,"fsimu",El_sig.fs,"lambda",s.wavelengthplan(l),"bias",vbias,"u_pi",u_pi,"linewidth",laser_linewidth,"randomkey",s.random_key+l+realiz).process(El_sig); signal_cell{l} = Polarization_Controller("mode","rot_power","desired_power",pol_rot(l)).process(Eml_out); end Opt_sig_wdm = Optical_Multiplex("fs_in",fdac*kover,"fs_out",upsample_pow*fdac*kover,... "lambda_center",1310,"random_key",0,"filtype",1,"B",120e9).process(signal_cell); Opt_sig_wdm = Amplifier("amp_mode","ideal_no_noise","gain_mode","output_power","amplification_db",3+10*log10(N)).process(Opt_sig_wdm); Opt_sig_wdm.spectrum("fignum",101,"displayname",'bla','normalizeTo0dB',0,'lambda0_nm',1310,'useWavelengthAxis',0); % Opt_sig_wdm.spectrum("fignum",101,"displayname",'bla','normalizeTo0dB',1,'max_num_lines',2); %%%%%% Fiber %%%%%% Opt_sig_wdm_fib=Opt_sig_wdm; segment_length = 1; % km nSegments = link_length/segment_length; zdw = 1310; D_local = 0; %if ~=0, simulation uses "segmented fiber with d+,d-) randomize_D = true; Dvec = getDispersionVector(nSegments, D_local, zdw, randomize_D, s.random_key+realiz); for seg = 1:nSegments Opt_sig_wdm_fib = DP_Fiber("L",segment_length,"D",Dvec(seg),"Dpmd",s.pmd,"Ds",0.07,... "beat_len",10,"corr_len",100,"dz",1,"manakov",0,... "gamma",s.gamma,"lambda",zdw,"n_waveplates",10,"SS_dphimax",0.01,... "SS_dzmax",50,"SS_dzmin",10,"X_alpha",0.3,"X_beta",0,"rng",1).process(Opt_sig_wdm_fib); end Opt_sig_wdm_fib.spectrum("fignum",realiz,"displayname",'bla','lambda0_nm',1310,'useWavelengthAxis',0); % Opt_sig_wdm_fib.move_it_spectrum("fignum",100212,"displayname",'bla'); % Opt_sig = Fiber("fsimu",Opt_sig.fs,"fiber_length",s.link_length/1000,"alpha",0.3,"D",0,"lambda0",1310,"s.gamma",0,"Dslope",0.07).process(Opt_sig) Opt_sig_wdm_demux = Optical_Demultiplex("attenuation",0,"B",200e9,"filtype",1,"fs_out",fdac*kover,"fs_in",fdac*kover*upsample_pow,"lambda_center",1310).process(Opt_sig_wdm_fib); for ri = 1:length(s.rop) for l = 1:N %%%%%% ROP %%%%%% Opt_sig_wdm_rx = Amplifier("amp_mode","ideal_no_noise","gain_mode","output_power","amplification_db",s.rop(ri)).process(Opt_sig_wdm_demux{l}); % rop+10*log10(N) %%%%%% PD Square Law %%%%%% assert(fdac*kover==Opt_sig_wdm_rx.fs,'Sampling Frequencies do not match! Check previous steps'); PD_sig = Photodiode("fsimu",fdac*kover,"dark_current",2e-08,"responsivity",1,"temperature",20,"nep",1.8e-11,"randomkey",s.random_key+l+realiz).process(Opt_sig_wdm_rx); % PD_sig.spectrum("fignum",222,"displayname",'bla','normalizeTo0dB',1); %%%%%% Low-pass RX (PD, El. Connectors and Scope %%%%%% rx_bwl = 100e9; PD_sig = Filter('filtdegree',4,"f_cutoff",rx_bwl,"fs",fdac*kover,"filterType",filtertypes.butterworth,"active",true).process(PD_sig); % %%%%%% Low-pass Scope %%%%%% Lp_scpe = Filter('filtdegree',4,"f_cutoff",80e9,"fs",fadc,"filterType",filtertypes.butterworth,"active",true); %%%%%% Scope %%%%%% Scpe_sig = Scope("fsimu",fdac*kover,"fadc",fadc,... "delay",0,"fixed_delay",0,"filtertype",filtertypes.butterworth,... "samplingdelay",0,"rand_samplingdelay",0,"freq_offset",0,"samp_jitter",0,... "adcresolution",8,"quantbuffer",0.1,'block_dc',1,'lpf_active',0,'H_lpf',Lp_scpe).process(PD_sig); Scpe_sig_2sps = Scpe_sig.resample("fs_out",2*fsym); % Scpe_sig.spectrum("fignum",222,"displayname",'bla','normalizeTo0dB',1); [~, Scpe_cell, ~, found_sync] = Scpe_sig_2sps.tsynch("reference", Symbols{l}, "fs_ref", fsym, "debug_plots", 1); Rx_sig = Scpe_cell{1}; Rx_sig = Rx_sig.normalize("mode","rms"); % FFE ffe_order = [50, 0, 0]; eq_ffe = EQ("Ne",ffe_order,"Nb",[0,0,0],"training_length",len_tr,"training_loops",5,"dd_loops",5,"K",2,"DCmu",mu_dc,"DDmu",[mu_ffe mu_dfe],"DFEmu",0.005,"FFEmu",0,"plotfinal",0,"ideal_dfe",0); ffe_results = ffe(eq_ffe,s.M,Rx_sig,Symbols{l},Tx_bits{l},... "precode_mode",duob_mode,... 'showAnalysis',0,... "postFFE",[],... "eth_style_symbol_mapping",0); output_ffe{l,ri,realiz} = ffe_results; %VNLE pf_ncoeffs = 1; ffe_order = [50, 5, 5]; eq_ = EQ("Ne",ffe_order,"Nb",dfe_order,"training_length",len_tr,"training_loops",5,"dd_loops",5,"K",2,"DCmu",mu_dc,"DDmu",[mu_ffe mu_dfe],"DFEmu",0.005,"FFEmu",0,"plotfinal",0,"ideal_dfe",1); pf_ = Postfilter("ncoeff",pf_ncoeffs,"useBurg",1); useviterbi = 0; if useviterbi mlse_ = MLSE_viterbi("duobinary_output",0,'M',s.M,'trellis_states',PAMmapper(s.M,0).levels); else mlse_ = MLSE("duobinary_output",0,'M',s.M,'trellis_states',PAMmapper(s.M,0).levels); end [vnle_results, mlse_results] = vnle_postfilter_mlse(eq_, pf_, mlse_, s.M, Rx_sig, Symbols{l},Tx_bits{l}, ... "precode_mode", duob_mode,... 'showAnalysis', 0, ... "postFFE", [],... "eth_style_symbol_mapping", 0); output_vnle{l,ri,realiz} = vnle_results; output_mlse{l,ri,realiz} = mlse_results; % DB tgt. useviterbi = 0; if useviterbi mlse_db_ = MLSE_viterbi("duobinary_output",0,'M',s.M,'trellis_states',PAMmapper(s.M,0).levels); else mlse_db_ = MLSE("DIR",[1,1],"duobinary_output",0,"M",s.M,"trellis_states",PAMmapper(s.M,0).levels); end ffe_order = [50, 5, 5]; eq_ = EQ("Ne",ffe_order,"Nb",dfe_order,"training_length",len_tr,"training_loops",5,"dd_loops",5,"K",2,"DCmu",mu_dc,"DDmu",[mu_ffe mu_dfe],"DFEmu",0.005,"FFEmu",0,"plotfinal",0,"ideal_dfe",1); dbt_results = duobinary_target(eq_, mlse_db_, s.M, Rx_sig, Symbols{l},Tx_bits{l}, ... "precode_mode", duob_mode, ... 'showAnalysis', 0,... "postFFE", []); output_dbt{l,ri,realiz} = dbt_results; end end res = struct(); res.settings = s; res.ffe = output_ffe; res.vnle = output_vnle; res.mlse = output_mlse; res.dbt = output_dbt; % Save results save(fullfile(output_root, fname), 'res', '-v7.3'); fprintf('Saved results to: %s\n', fullfile(output_root, fname)); disp(datetime('now','TimeZone','local','Format','yyyyMs.Mdd_HHmmss')); end function dispersion_vector = getDispersionVector(N, D, ref_zdw, randomize_ZDW, randomkey) % s.MATLAB version of the Python generator shown above. % Returns an N×1 vector (ps/(nm·km)). % % D is the nominal dispersion magnitude. For D>0 the link is segmented with % alternating sign (+D, -D, +D, …). For D==0 it is flat (0) except for % ZDW randomization. The ZDW detuning is ~N(0, 2 nm) around 1310 nm and is % converted to dispersion via 0.09 ps/(nm·km) per nm. % constants (matching the Python code) meanLambda_nm = 1310; % center wavelength sigma_nm = 2; % ZDW sigma Dslope = 0.07; % ps/(nm·km) per nm detuning % random ZDW-induced dispersion offset if randomize_ZDW rng(randomkey, 'twister'); rand_zdws_nm = meanLambda_nm + sigma_nm .* randn(N,1); rand_D = (rand_zdws_nm - ref_zdw) .* Dslope; % ps/(nm·km) else rand_D = zeros(N,1); end % nominal segmented pattern (match Python intent; keep length N) if D > 0 base = (-1) .^ ((0:N-1).'); % +1,-1,+1,-1,... else % D == 0 (or anything else) base = ones(N,1); end dispersion_vector = base .* D + rand_D; % ps/(nm·km) end