Bald fertig für richtige Nutzung - Move_it vergleich fertig

Complete Checkup with Move_it: this framework is an almost perfect reproduction.
This commit is contained in:
Silas Oettinghaus
2023-06-08 15:33:57 +02:00
parent 2868887a15
commit 2aeacafe78
14 changed files with 198 additions and 122 deletions

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@@ -33,11 +33,6 @@ classdef Electricalsignal < Signal
end end
function obj = normalize(obj)
obj.signal = obj.signal/sqrt(mean(abs(obj.signal),"all"));
end
end end

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@@ -21,11 +21,6 @@ classdef Informationsignal < Signal
end end
function obj = normalize(obj)
obj.signal = obj.signal/sqrt(mean(abs(obj.signal),"all"));
end
end end
end end

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@@ -33,12 +33,6 @@ classdef Opticalsignal < Signal
end end
function obj = normalize(obj)
obj.signal = obj.signal/sqrt(mean(abs(obj.signal).^2));
end
function pow = power(obj) function pow = power(obj)
pow = mean(abs(obj.signal.^2)) ; pow = mean(abs(obj.signal.^2)) ;

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@@ -106,8 +106,13 @@ classdef Signal
end end
%% Add signals from one signal to another, the first object will sustain
function Sum = plus(X,Y)
Sum = X; %first input object will sustain
Sum.signal = X.signal + Y.signal;
end
%% Display length %% Display length
function return_length = length(obj) function return_length = length(obj)
%METHOD1 Summary of this method goes here %METHOD1 Summary of this method goes here
% Detailed explanation goes here % Detailed explanation goes here
@@ -135,7 +140,7 @@ classdef Signal
end end
%% Resample Signal %% Resample Signal
function obj = resample(obj,options) function obj = resample(obj,options)
arguments arguments
@@ -203,7 +208,7 @@ classdef Signal
psd = psd/length(Fsignal); psd = psd/length(Fsignal);
%smoothing %smoothing
psd = smooth(psd,50); psd = smooth(psd,1000);
psd_plot = 20*log10(psd); psd_plot = 20*log10(psd);
@@ -255,6 +260,57 @@ classdef Signal
end end
%%
function obj = normalize(obj,options)
arguments
obj Signal
options.mode normalization_mode = normalization_mode.rms
end
switch options.mode
case normalization_mode.rms
obj.signal = obj.signal/sqrt(mean(abs(obj.signal).^2,"all"));
case normalization_mode.oneone
obj.signal = obj.signal/max(abs(obj.signal));
end
end
%%
function obj = delay(obj,options)
arguments
obj Opticalsignal
options.delay_meter double = 0
end
delay_t = options.delay_meter /(physconst("LightSpeed")/1.4677);
delay_n = round(delay_t .* obj.fs);
% build "long" hann window to fade the signal in and out
% -> prevent hard step in the signal!
hann_wind = hann(200);
ones_wind = ones(size(obj.signal));
ones_wind(1:100) = hann_wind(1:100);
ones_wind(end-100:end) = hann_wind(end-100:end);
% subtract average
mu = mean(obj.signal,"all");
obj.signal = obj.signal - mu;
%apply hann
obj.signal = obj.signal .* ones_wind;
%add average again
obj.signal = obj.signal + mu;
% finally circshift the signal
obj.signal=circshift(obj.signal,delay_n);
end
end end
end end

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@@ -32,7 +32,7 @@ classdef AWG
% Detailed explanation goes here % Detailed explanation goes here
arguments arguments
options.preset = [] ; options.preset = 'none';
options.kover = 16; options.kover = 16;
options.repetitions = 1; options.repetitions = 1;
options.normalize = 1; options.normalize = 1;

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@@ -50,6 +50,8 @@ classdef PAMmapper
pam_sig=2*pam_sig-3; pam_sig=2*pam_sig-3;
end end
pam_sig = pam_sig .* 1/sqrt(5);
case 3 case 3
% 8-ASK: % 8-ASK:
@@ -86,8 +88,6 @@ classdef PAMmapper
%28.03.2023 - Silas Oett. - Extracted from digi_demod.m %28.03.2023 - Silas Oett. - Extracted from digi_demod.m
% %
obj.thresholds = 0;
switch log2(obj.M) switch log2(obj.M)
case 1 case 1
@@ -106,6 +106,7 @@ classdef PAMmapper
elseif obj.unipolar==1 elseif obj.unipolar==1
thres=[0.5,1.5,2.5]; thres=[0.5,1.5,2.5];
end end
thres = thres .* 1/sqrt(5);
case 3 case 3
@@ -174,6 +175,8 @@ classdef PAMmapper
1-comp_real(:,:,4)+comp_real(:,:,12)]; 1-comp_real(:,:,4)+comp_real(:,:,12)];
end end
data_out = data_out';
end end

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@@ -41,7 +41,7 @@ classdef Pulseformer
signalclass_in.signal = obj.process_(signalclass_in.signal); signalclass_in.signal = obj.process_(signalclass_in.signal);
% append to logbook % append to logbook
lbdesc = ['Applied Pulseshaping']; lbdesc = 'Applied Pulseshaping';
signalclass_in = signalclass_in.logbookentry(lbdesc); signalclass_in = signalclass_in.logbookentry(lbdesc);
% write to output % write to output
@@ -83,23 +83,56 @@ classdef Pulseformer
if obj.pulseform == pulseform.rrc if obj.pulseform == pulseform.rrc
%Bau das Filter (hier rrc) %Bau das Filter (hier rrc)
racos_len = obj.pulselength ; racos_len = obj.pulselength*2 ;
alpha = obj.rrcalpha; alpha = obj.rrcalpha;
h = rcosdesign(alpha,racos_len,sps); h = rcosdesign(alpha,racos_len,sps);
h = h./ max(h);
end end
%Apply Filter using Matlab build in fctn. % Apply filter the long way (from move_it)
data_out = upfirdn(data_in,h,up,dn); % block length in samples
data_in = data_in';
blen = length(data_in)*sps;
% oversample symbol sequence
symbolov=zeros(size(data_in,1),blen);
symbolov(:,1:sps:blen-sps+1)=data_in;
%cut signal, which is longer due to fir filter H=fft(h,blen);
st = round(up/dn*racos_len/2); %we need to cut y_out
en = round(st + (length(data_in)*up/dn) -1); % Convolution of Bit sequence with impulse response
data_out = data_out(st:en); % cyclic convolution
data_out=ifft( fft(symbolov.') .* repmat( H,size(data_in,1),1 ).' ).';
data_out = circshift(data_out,[0 -(obj.pulselength*sps)]);
if rem(obj.fdac,obj.fsym)
data_out = data_out(1:dn:end); %!
end
% %Apply Filter using Matlab build in fctn.
% data_out = upfirdn(data_in,h,up,dn);
%
% %cut signal, which is longer due to fir filter
% st = round(up/dn*racos_len/2); %we need to cut y_out
% en = round(st + (length(data_in)*up/dn) -1);
%
% data_out = data_out(st:en);
%scaling?! see pulsef module line 696
scale = max(max([abs(real(data_out)) abs(imag(data_out))])); %find max value from real and imag part
data_out = data_out./scale;
data_out = data_out';
%Check output integrity %Check output integrity
if round(up/dn * length(data_in)) ~= length(data_out) if round(up/dn * length(data_in)) ~= length(data_out)
warning('Check signal length after pulse shaping'); %warning('Check signal length after pulse shaping');
disp('Check signal length after pulse shaping');
end end

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@@ -149,6 +149,7 @@ classdef Amplifier
end end
function nase_numeric = generateAseNoise(~, nase, fs, dimension) function nase_numeric = generateAseNoise(~, nase, fs, dimension)
rng(2023);
nase_numeric = (randn(dimension) + 1i*randn(dimension))*sqrt(nase/2*fs) ; nase_numeric = (randn(dimension) + 1i*randn(dimension))*sqrt(nase/2*fs) ;
end end

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@@ -43,14 +43,13 @@ classdef Filter
function signalclass_out = process(obj,signalclass_in) function signalclass_out = process(obj,signalclass_in)
% actual processing of the signal % actual processing of the signal
signalclass_in.signal = obj.process_(signalclass_in.signal); signalclass_out = signalclass_in;
signalclass_out.signal = obj.process_(signalclass_in.signal);
% append to logbook % append to logbook
filterdesc = [num2str(obj.filtdegree),'. order ',char(obj.filterType),' filter with f_cutoff at ', num2str(obj.f_cutoff*1e-9), ' GHz.']; filterdesc = [num2str(obj.filtdegree),'. order ',char(obj.filterType),' filter with f_cutoff at ', num2str(obj.f_cutoff*1e-9), ' GHz.'];
signalclass_in = signalclass_in.logbookentry(filterdesc); signalclass_out = signalclass_out.logbookentry(filterdesc);
% write to output
signalclass_out = signalclass_in;
end end

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@@ -23,7 +23,7 @@ classdef Fiber
%FIBER Construct an instance of this class %FIBER Construct an instance of this class
% Detailed explanation goes here % Detailed explanation goes here
arguments arguments
options.fsimu options.fsimu
options.fiber_length = 0 options.fiber_length = 0
options.alpha = 0.2 options.alpha = 0.2
options.D = 17 options.D = 17
@@ -42,22 +42,20 @@ classdef Fiber
obj.gamma = options.gamma; obj.gamma = options.gamma;
obj.dphimax = options.dphimax; obj.dphimax = options.dphimax;
obj.b2 = -obj.D*obj.lambda0^2/(2*pi*Constant.LightSpeed);
obj.b3 = ((obj.lambda0.^2/(2*pi*Constant.LightSpeed)).^2*obj.Dslope);
obj.alpha_lin = obj.alpha/10*log(10)/1000;
end end
function signalclass_out = process(obj,signalclass_in) function signalclass_out = process(obj,signalclass_in)
% actual processing of the signal (steps 1. - 3.) % actual processing of the signal (steps 1. - 3.)
signalclass_in.signal = obj.process_(signalclass_in.signal); signalclass_in.signal = obj.process_(signalclass_in.signal);
% append to logbook % append to logbook
lbdesc = 'Fiber '; lbdesc = 'Fiber ';
signalclass_in = signalclass_in.logbookentry(lbdesc); signalclass_in = signalclass_in.logbookentry(lbdesc);
% write to output % write to output
signalclass_out = signalclass_in; signalclass_out = signalclass_in;
end end
@@ -66,6 +64,10 @@ classdef Fiber
%METHOD1 Summary of this method goes here %METHOD1 Summary of this method goes here
% Detailed explanation goes here % Detailed explanation goes here
obj.b2 = -obj.D*obj.lambda0^2/(2*pi*Constant.LightSpeed);
obj.b3 = ((obj.lambda0.^2/(2*pi*Constant.LightSpeed)).^2*obj.Dslope);
obj.alpha_lin = obj.alpha/10*log(10)/1000;
N = length(opt_in); N = length(opt_in);
faxis = linspace(-obj.fsimu/2,obj.fsimu/2,N+1); faxis = linspace(-obj.fsimu/2,obj.fsimu/2,N+1);
faxis = ifftshift(faxis(:,1:end-1)); faxis = ifftshift(faxis(:,1:end-1));
@@ -109,7 +111,7 @@ classdef Fiber
z_prop = z_prop + dz; z_prop = z_prop + dz;
maxPow = obj.gamma*max(abs(yout).^2); maxPow = obj.gamma*max(abs(yout).^2);
Leff = obj.dphimax/maxPow; Leff = obj.dphimax/maxPow;
dz_new = Leff; dz_new = Leff;

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@@ -20,6 +20,8 @@ classdef Scope
filtertype filtertype
lpf_bw lpf_bw
block_dc
%during construction %during construction
%during process %during process
@@ -47,24 +49,17 @@ classdef Scope
options.filtertype = filtertypes.bessel_bilin; options.filtertype = filtertypes.bessel_bilin;
options.lpf_bw = 120e9; options.lpf_bw = 120e9;
options.block_dc = 1;
end end
obj.fsimu = options.fsimu; fn = fieldnames(options);
obj.fadc = options.fadc; for n = 1:numel(fn)
obj.adcresolution = options.adcresolution; try
obj.quantbuffer = options.quantbuffer; obj.(fn{n}) = options.(fn{n});
end
end
obj.rand_samplingdelay = options.rand_samplingdelay; % use a randomized sample delay INSTEAD of samplingdelay
obj.samplingdelay = options.samplingdelay; %specifiy a sampling delay
obj.freq_offset = options.freq_offset; %offset of the sampler
obj.samp_jitter = options.samp_jitter; %include jitter in [s]
obj.fixed_delay = options.fixed_delay; %fix the delay of the filter or use minimal delay for kausal system
obj.delay = options.delay; %specify a fixed delay of the filter
obj.filtertype = options.filtertype;
obj.lpf_bw = options.lpf_bw;
end end
@@ -91,14 +86,17 @@ classdef Scope
% Detailed explanation goes here % Detailed explanation goes here
% sample signal % sample signal
% TODO: implement and test the delays. Also look for delay of % TODO: implement and test the delays.
% lpf filter
%yout = obj.sampleSignal(xin); % resample
yout = resample(xin,obj.fadc,obj.fsimu); yout = resample(xin,obj.fadc,obj.fsimu);
% quantize signal % quantize signal
yout = obj.quantize(yout); yout = obj.quantize(yout);
if obj.block_dc
yout = yout-mean(yout,1);
end
end end

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@@ -0,0 +1,8 @@
classdef normalization_mode < int32
enumeration
rms (1)
oneone (2)
end
end

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@@ -1,7 +1,7 @@
function [bits,errors,BER] = calc_ber(data_in,data_ref,skip) function [bits,errors,BER] = calc_ber(data_in,data_ref,skip)
data_ref=logical(data_ref); data_ref=logical(data_ref)';
data_in = logical(data_in); data_in = logical(data_in)';
bits = 0; bits = 0;
errors=0; errors=0;
@@ -10,18 +10,14 @@ data_ref_pointer=0;
% Determine BER % Determine BER
bits = bits+size(data_in,2)-skip; bits = bits+size(data_in,2)-skip;
try try
errors = sum( data_in(:,skip+1:end,:) ~= data_ref(:,skip+1:end,:),2 ); errors = sum( data_in(:,skip+1:end,:) ~= data_ref(:,skip+1:end,:),2 );
catch catch
%warning('BER calculation not optimal: Arrays have incompatible sizes for this operation.') %warning('BER calculation not optimal: Arrays have incompatible sizes for this operation.')
errors = NaN; errors = NaN;
end end
try
errors = sum( data_in(:,skip+1:end,:) ~= data_ref(:,skip+1:end-1,:),2 );
end
try
errors = sum( data_in(:,skip+1:end,:) ~= data_ref(:,skip+1:end-2,:),2 );
end
BER = sum(errors)/sum(bits); BER = sum(errors)/sum(bits);

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@@ -1,6 +1,6 @@
rng(2023); rng(2020);
%% Set Simulation Variables %% Set Simulation Variables
@@ -32,48 +32,50 @@ fsimu = kover * fdac ;
digimod = PAMmapper(M,0); digimod = PAMmapper(M,0);
pulsef = Pulseformer("pulseform","rrc","fdac",fdac,"fsym",fsym,"pulselength",32,"rrcalpha",0.05); pulseform = Pulseformer("pulseform","rrc","fdac",fdac,"fsym",fsym,"pulselength",32,"rrcalpha",0.05);
awg = AWG('preset','M8199B','fdac',fdac,'kover',kover,'lpf_active',1,'f_cutoff',56e9,'lpf_type',filtertypes.gaussian,'bit_resolution',5.5); 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",60e9,"fsamp",fdac,"filterType",filtertypes.bessel_inp); lp_laser = Filter('filtdegree',1,"f_cutoff",50e9,"fsamp",fdac*kover,"filterType",filtertypes.bessel_inp);
u_pi = 4.6; u_pi = 4.6;
vbias = (0.5*u_pi)-u_pi; vbias = (0.5*u_pi)-u_pi;
extmodlaser = EML("mode",eml_mode.im_cosinus,"power",15,"fsimu",fsimu,"lambda",1550,"bias",vbias,"u_pi",u_pi,"linewidth",10000); extmodlaser = EML("mode",eml_mode.im_cosinus,"power",5,"fsimu",fsimu,"lambda",1550,"bias",vbias,"u_pi",u_pi,"linewidth",1e6);
amp = Amplifier("amp_mode","ideal_no_noise","amplification_db",0,"gain_mode","output_power");
fib = Fiber("fsimu",fdac*kover,"fiber_length",1,"alpha",0.2,"D",17,"lambda0",1550,"gamma",0); fib = Fiber("fsimu",fdac*kover,"fiber_length",1,"alpha",0.2,"D",17,"lambda0",1550,"gamma",0);
optatten = Amplifier("amp_mode","ideal_no_noise","gain_mode","output_power","amplification_db",0); reflectionpoint = Amplifier("amp_mode","ideal_no_noise","gain_mode","gain","amplification_db",-20);
reflectionprop = Fiber("fsimu",fdac*kover,"fiber_length",1,"alpha",0.2,"D",17,"lambda0",1550,"gamma",0);
opticatten = Amplifier("amp_mode","ideal_no_noise","gain_mode","output_power","amplification_db",0);
edfaamp = Amplifier("amp_mode","edfa_increase_nase","gain_mode","output_power","amplification_db",0,"nase_mode","generate_ase","noifig",5); edfaamp = Amplifier("amp_mode","edfa_increase_nase","gain_mode","output_power","amplification_db",0,"nase_mode","generate_ase","noifig",5);
phdiode = Photodiode("fsimu",fdac*kover,"dark_current",2e-08,"responsivity",1,"temperature",20); phdiode = Photodiode("fsimu",fdac*kover,"dark_current",2e-08,"responsivity",1,"temperature",20);
lp_diode = Filter('filtdegree',1,"f_cutoff",80e9,"fsamp",fdac,"filterType",filtertypes.bessel_inp); lp_diode = Filter('filtdegree',1,"f_cutoff",50e9,"fsamp",fdac*kover,"filterType",filtertypes.bessel_inp);
scp = Scope("fsimu",fdac*kover,"fadc",fadc,... scp = Scope("fsimu",fdac*kover,"fadc",fadc,...
"delay",0,"fixed_delay",0,"lpf_bw",113e9,"filtertype",filtertypes.butterworth,... "delay",0,"fixed_delay",0,"lpf_bw",113e9,"filtertype",filtertypes.butterworth,...
"samplingdelay",0,"rand_samplingdelay",0,"freq_offset",0,"samp_jitter",0,... "samplingdelay",0,"rand_samplingdelay",0,"freq_offset",0,"samp_jitter",0,...
"adcresolution",6,"quantbuffer",0.1); "adcresolution",6,"quantbuffer",0.1,'block_dc',1);
eq = EQ("K",2,"plottrain",0,"plotfinal",0,... eq = EQ("K",2,"plottrain",0,"plotfinal",0,...
"training_length",4096,"training_loops",5,... "training_length",4096,"training_loops",5,...
"Ne",[30,0,0],"Nb",[0,0,0],... "Ne",[50,0,0],"Nb",[0,0,0],...
"DCmu",0.005,"DDmu",[0.0004 0.0004 0.0004 0.0004 ],"DFEmu",0.002,"FFEmu",0.00,... "DCmu",0.005,"DDmu",[0.0004 0.0004 0.0004 0.0004 ],"DFEmu",0.005,"FFEmu",0.00,...
"dd_loops",2,"epsilon",[10 100 1000 ],"M",4,... "dd_loops",2,"epsilon",[10 100 1000 ],"M",4,...
"thres",[0.005 0.004 0.0005 ],"l1act",0,"delay",0,"rho",0.0005,"ideal_dfe",0,"DB_aim",0); "thres",[0.005 0.004 0.0005 ],"l1act",0,"delay",1,"rho",0.0005,"ideal_dfe",0,"DB_aim",0);
%% PROCESS %% PROCESS
output_pow = 0 fiblen = 0;
for lp1 = 1:length(output_pow) for lp1 = 1:length(fiblen)
% change parameters % change parameters
optatten.amplification_db = output_pow(lp1); fib.fiber_length = fiblen(lp1);
% PRBS Generation % PRBS Generation
@@ -93,25 +95,38 @@ for lp1 = 1:length(output_pow)
reference = mod_out; reference = mod_out;
% shape shape % shape shape
mod_out = pulsef.process(mod_out); X = pulseform.process(mod_out);
test = applyPulseShaping(reference.signal,fsym,fdac); test = applyPulseShaping(reference.signal,fsym,fdac);
% AWG -> ELECTRICAL DOMAIN % AWG -> ELECTRICAL DOMAIN
X = awg.process(mod_out); awg_out = awg.process(X);
X = lp_laser.process(awg_out);
X = lp_laser.process(X); X = lp_laser.process(X);
X = X.normalize; X = X.normalize("mode","oneone");
X.signal = X.signal .* 1.3800;
% Laser; Modulation -> OPTICAL DOMAIN % Laser; Modulation -> OPTICAL DOMAIN
X = extmodlaser.process(X); X = extmodlaser.process(X);
%X.spectrum(fsimu,"displayname",'laser out','figurename','after laser');
%X = amp.process(X);
% Fiber Propagation % Fiber Propagation
X = fib.process(X); X = fib.process(X);
X = optatten.process(X);
%% Reflect with attenuation
R = reflectionpoint.process(X);
% Propagate
R = reflectionprop.process(R);
% Delay
R = R.delay("delay_meter",200);
% Add together
X = X+R;
%%
X = opticatten.process(X);
X = edfaamp.process(X); X = edfaamp.process(X);
% Photo Diode -> ELECTRICAL DOMAIN % Photo Diode -> ELECTRICAL DOMAIN
@@ -124,8 +139,8 @@ for lp1 = 1:length(output_pow)
% Resample to Symbol Rate % Resample to Symbol Rate
X = X.resample("fs_out",2*fsym,"fs_in",fadc); X = X.resample("fs_out",2*fsym,"fs_in",fadc);
% INFORMATION SIGNAL % Normalize
X = X.normalize; X = X.normalize("mode","rms");
% Equalizer % Equalizer
eq_out = eq.process(X,reference); eq_out = eq.process(X,reference);
@@ -135,7 +150,8 @@ for lp1 = 1:length(output_pow)
demap_out = digimod.demap(eq_out); demap_out = digimod.demap(eq_out);
% BER % BER
[bits,errors,BER] = calc_ber(demap_out.signal(:,1:end-1),bitpattern(1:end,:)',0); [bits,errors,BER] = calc_ber(demap_out.signal(1:end-2,:),bitpattern(1:end,:),0);
disp(['BER: ', sprintf('%2E',BER), ' ERRORS: ' ,num2str(sum(errors))]); disp(['BER: ', sprintf('%2E',BER), ' ERRORS: ' ,num2str(sum(errors))]);
bercurve(lp1) = BER; bercurve(lp1) = BER;
@@ -145,33 +161,13 @@ end
%% Generate some Plots %% Generate some Plots
if 0 if 1
col = cbrewer2('Paired',8); col = cbrewer2('Paired',8);
figure(22) figure(22)
clf clf
% subplot(3,1,1)
% hold on
% plot(reference.signal(10000:end-20),'DisplayName','Tx','Color',col(1,:),'LineWidth',3);
% plot(rx_series(10000:end-20),'DisplayName','Rx','Color',col(6,:));
% title('Modulated Sequence Tx - Rx');
% legend
% hold off
subplot(2,1,1) subplot(2,1,1)
hold on hold on
plot(reference.signal(4150:4175),'DisplayName','Tx','Color',col(1,:),'LineWidth',3); plot(reference.signal(4150:4175),'DisplayName','Tx','Color',col(1,:),'LineWidth',3);
@@ -181,7 +177,7 @@ if 0
hold off hold off
subplot(2,1,2) subplot(2,1,2)
hold on hold on
stem(demap_out.signal(1,4150:4175),'DisplayName','Tx','Color',col(1,:),'LineStyle','-','LineWidth',5) stem(demap_out.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) stem(bitpattern(4150:4175,1)','DisplayName','Rx','Color',col(6,:),'LineStyle','--','LineWidth',2)
title('Bitpattern Tx - Rx'); title('Bitpattern Tx - Rx');
legend legend
@@ -193,7 +189,7 @@ if 0
figure(12) figure(12)
sgtitle('') sgtitle('')
subplot(1,4,1:2) subplot(1,4,1:2)
scatter(1:4:X.length,X.signal(1:4:end),4,'.','MarkerEdgeColor',col(5,:),'DisplayName','Before EQ'); scatter(1:4:X.length,X.signal(1:4:end),4,'.','MarkerEdgeColor',col(6,:),'DisplayName','Before EQ');
xlim([1, xax(end)]); xlim([1, xax(end)]);
%ylim([-2 2]); %ylim([-2 2]);
xlabel('Sampling Index') xlabel('Sampling Index')