Files
imdd_silas/projects/Diss/simulation_nonlin_dsp.m
2026-06-21 23:11:13 +02:00

242 lines
8.3 KiB
Matlab

%%% Run parameters
% TX
M = 4;
m = floor(log2(M)*10)/10;
fsym = 160e9;
apply_pulsef = 0;
fdac = 256e9;
fadc = 256e9;
random_key = 1;
rcalpha = 0.05;
kover = 16;
vbias_rel = 0.5;
u_pi = 3.2;
vbias = -vbias_rel*u_pi;
laser_wavelength = 1310;
laser_linewidth = 0;
eml_alpha = 0;
% Channel
link_length = 0;
vnle_order1 = 50;
vnle_order2 = 0;
vnle_order3 = 0;
vnle_order=[vnle_order1,vnle_order2,vnle_order3];
dfe_order = [0 0 0];
alpha = 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;
dfe_ = sum(dfe_order)>0;
duob_mode = db_mode.no_db;
cols = linspecer(6);
rop = -6;
bwl = 0.5:0.1:1.5;
nonlin_mod = 0.5:0.025:0.7;
fsym = ones(size(nonlin_mod)).*fsym;
ffe_results = {};
mlse_results_lin= {};
vnle_results= {};
mlse_results_nonlin= {};
mlse_results_nonlin_states= {};
g_eye = GifWriter('Name','eye','Parallel',true);
g_mod = GifWriter('Name','modulator','Parallel',true);
for r = 1:length(nonlin_mod)
Pform = Pulseformer("fsym",fsym(r),"fdac",4*fsym(r),"pulse","rc","pulselength",16,"alpha",rcalpha);
apply_pulsef = 0;
[Digi_sig,Symbols,Tx_bits] = PAMsource(...
"fsym",fsym(r),"M",M,"order",18,"useprbs",0,...
"fs_out",fdac,...
"applyclipping",0,"clipfactor",1.5,...
"applypulseform",apply_pulsef,"pulseformer",Pform,...
"randkey",random_key,...
"mrds_code",0,"mrds_blocklength",512,"duobinary_mode",duob_mode).process();
% El_sig = AWG("fdac",fdac,"f_cutoff",fsym(r),"lpf_active",0,"kover",kover,"bit_resolution",12,"upsampling_method","samplehold","precomp_sinc_rolloff",0).process(Digi_sig);
El_sig = M8199B("kover",kover).process(Digi_sig);
% AWG("fdac",fdac,"f_cutoff",fsym(r),"lpf_active",0,"kover",kover,"bit_resolution",12,"upsampling_method","samplehold","precomp_sinc_rolloff",0).process(Digi_sig);
%%%%% Low-pass el. components %%%%%%
tx_bwl = 85e9;
El_sig = Filter("filtdegree",4,"f_cutoff",tx_bwl,"fs",fdac*kover, ...
"filterType",filtertypes.bessel_inp,"active",true).process(El_sig);
%%%%% Electrical Driver Amplifier %%%%%%
El_sig = El_sig.normalize("mode","oneone");
% El_sig = El_sig.setPower(1,"dBm");
% figure;histogram(El_sig.signal);
%%%%% MODULATE E/O CONVERSION %%%%%
% scaling = nonlin_mod(r)*(u_pi/2-abs(vbias-u_pi/2));
% El_sig = El_sig .* scaling;
vbias = -nonlin_mod(r)*u_pi;
[Opt_sig] = EML("mode",eml_mode.im_cosinus,"power",3,"fsimu",El_sig.fs, ...
"lambda",laser_wavelength,"bias",vbias,"u_pi",u_pi, ...
"linewidth",laser_linewidth,"randomkey",random_key+1, ...
"alpha",eml_alpha).process(El_sig);
if 1
figure(15);
hold on
scatter(El_sig.signal(1:100000)+vbias,(abs(Opt_sig.signal(1:100000)).^2)*1e3,0.1,'.','DisplayName','Modulator TF')
xlabel('Input in V')
ylabel('abs(Eopt)2 in mW','Interpreter','latex')
ylim([0 2]);
xlim([-3 0]);
g_mod.addFrame(15, r);
Opt_sig.eye(fsym(r), M, "fignum", 103837);
g_eye.addFrame(103837, r);
end
%%%%%% Fiber %%%%%%
Opt_sig = Fiber("fsimu",Opt_sig.fs,"fiber_length",link_length,"alpha",0.3,"D",0,"lambda0",1310,"gamma",0,"Dslope",0.07).process(Opt_sig);
%%%%%% ROP %%%%%%
Opt_sig = Amplifier("amp_mode","ideal_no_noise","gain_mode","output_power","amplification_db",rop).process(Opt_sig);
%%%%%% PD Square Law %%%%%%
PD_sig = Photodiode("fsimu",fdac*kover,"dark_current",2e-08,"responsivity",0.6,"temperature",20,"nep",1.8e-11).process(Opt_sig);
%%%%%% Low-pass RX (PD, El. Connectors and Scope %%%%%%
rx_bwl = 90e9;
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",110e9,"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',1,'H_lpf',Lp_scpe).process(PD_sig);
txPulseformer = [];
if apply_pulsef
txPulseformer = Pform;
end
Rx_sig = preprocessSignal(Scpe_sig, Symbols, fsym(r), ...
"mode","auto", ...
"tx_pulseformer",txPulseformer, ...
"debug_plots",0,"gaussian_cutoff_factor",0.55,"apply_gaussian_filter",true);
Rx_sig = Rx_sig.normalize("mode","rms");
Rx_sig.signal = Rx_sig.signal(1:2*Symbols.length);
Rx_sig.spectrum()
if 1
%% 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,M,Rx_sig,Symbols,Tx_bits,...
% "precode_mode",duob_mode,...
% 'showAnalysis',0,...
% "postFFE",[],...
% "eth_style_symbol_mapping",0);
%
% ffe_results.metrics.print;
% ffe_results.config.equalizer_structure = "ffe";
%
%% MLSE linear
pf_ncoeffs = 1;
ffe_order = [50, 0, 0];
eq_ = 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",1);
pf_ = Postfilter("ncoeff",pf_ncoeffs,"useBurg",1);
mlse_ = MLSE("duobinary_output",0,'M',M,'trellis_states',PAMmapper(M,0).levels,'scale_mode',2,'trellis_exclusion',0,'trellis_state_mode',2,'debug',0);
[ffe_results{r}, mlse_results_lin{r}] = vnle_postfilter_mlse(eq_, pf_, mlse_, M, Rx_sig, Symbols, Tx_bits, ...
"precode_mode", duob_mode,...
'showAnalysis', 0, ...
"postFFE", [],...
"eth_style_symbol_mapping", 0);
mlse_results_lin{r}.metrics.print;
ffe_results{r}.metrics.print;
%% MLSE nonlinear pre
pf_ncoeffs = 1;
ffe_order = [50, 1, 0];
eq_ = 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",1);
pf_ = Postfilter("ncoeff",pf_ncoeffs,"useBurg",1);
mlse_ = MLSE("duobinary_output",0,'M',M,'trellis_states',PAMmapper(M,0).levels,'scale_mode',2,'trellis_exclusion',0,'trellis_state_mode',2);
[vnle_results{r}, mlse_results_nonlin{r}] = vnle_postfilter_mlse(eq_, pf_, mlse_, M, Rx_sig, Symbols, Tx_bits, ...
"precode_mode", duob_mode,...
'showAnalysis', 0, ...
"postFFE", [],...
"eth_style_symbol_mapping", 0);
mlse_results_nonlin{r}.metrics.print;
vnle_results{r}.metrics.print;
%% nonlinear states MLSE linear pre
pf_ncoeffs = 1;
ffe_order = [50, 0, 0];
eq_ = 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",1);
pf_ = Postfilter("ncoeff",pf_ncoeffs,"useBurg",1);
mlse_ = MLSE("duobinary_output",0,'M',M,'trellis_states',PAMmapper(M,0).levels,'scale_mode',2,'trellis_exclusion',0,'trellis_state_mode',3);
[~, mlse_results_nonlin_states{r}] = vnle_postfilter_mlse(eq_, pf_, mlse_, M, Rx_sig, Symbols, Tx_bits, ...
"precode_mode", duob_mode,...
'showAnalysis', 0, ...
"postFFE", [],...
"eth_style_symbol_mapping", 0);
mlse_results_nonlin_states{r}.metrics.print;
end
end
g_mod.compile(15);
g_eye.compile(103837);
%%
figure();hold on;
plot(nonlin_mod,cellfun(@(x) x.metrics.BER, ffe_results),'DisplayName','FFE')
plot(nonlin_mod,cellfun(@(x) x.metrics.BER, vnle_results),'DisplayName','VNLE')
plot(nonlin_mod,cellfun(@(x) x.metrics.BER, mlse_results_lin),'DisplayName','FFE+MLSE')
plot(nonlin_mod,cellfun(@(x) x.metrics.BER, mlse_results_nonlin_states),'DisplayName','FFE+nonlin. states MLSE')
plot(nonlin_mod,cellfun(@(x) x.metrics.BER, mlse_results_nonlin),'DisplayName','VNLE+MLSE')
xlabel('Nonlinear Driving');
ylabel('BER')
set(gca,'YScale','log');
legend;
ylim([1e-4 1e-1]);
beautifyBERplot;