BO-LSTM回归预测 | Matlab贝叶斯算法优化长短时记忆网络回归预测

%% Example 'GpsMultiCorrelator' #3: Generation of energy matrices resulting from non-coherent integrations with different periods
%  
%  Generation of energy matrices resulting from the accumulation of non-coherent correlation results, over different periods, between:
%  - A received signal including a GPS signal,
%  - A local signal matching in terms of PRN, Doppler and code phase.

% Parameters
SamplingPeriod    = 100e-9;
CarrierFrequency  = 0;
PRN               = 3;
CN0               = 45*10;
Doppler           = 0;
CodePhase         = 0;
Duration          = 25e-3;

% Creation of 'GpsSignals' object
GPS = ...
    GpsSig服务器托管网nals('SamplingPeriod',   SamplingPeriod,...
               'CarrierFrequency', CarrierFrequency,...
               'NextValues',       'replace',...
               'PRN',              PRN,...
               'CN0',              CN0,...
               'Doppler',          Doppler,...
               'CodePhase',        CodePhase);

% Creation of 'GpsMultiCorrelator' object
MultiCorrelator = ...
    GpsMultiCorrelator('SamplingPeriod',                 SamplingPeriod,...
                       'CarrierFrequency',               CarrierFrequency,...
                       'FilterFrequencies',              -4000:500:+4000-500,...
                       'CorrelatorCodePhases',           -4:0.5:+4-0.5,...    
                       'PRN',                            PRN,...
                       'Doppler',                        Doppler,...
                       'CodePhase',                      CodePhase,...
                       'CodePhaseIncrement',             0,...
                       'NonCoherentIntegrationPeriod',   5e-3);

    
for n = 1:6
    
    % Signal duration/non-coherent integration period
    Duration = n*5e-3;
    
    % Update of GPS signals
    GPS.update('Duration',Duration);
               
    % Setting of non-coherent integration period
    MultiCorrelator.set('NonCoherentIntegrationPeriod',Duration);
        
    % Correlation   
    MultiCorrelator.correlate(GPS.Values);
    
end

% Figure
Figure = ...
    figure('Color','w','Name','');
Axes = subplot(4,1,1:3,'Parent',  Figure,'NextPlot','Add');

% Display of energy matrices
M = numel(MultiCorrelator.EnergyMatrices);
for m = 1:M
    [CorrelatorCodePhases_,FilterFrequencies_] = meshgrid(MultiCorrelator.EnergyMatrices(m).CodePhases,MultiCorrelator.EnergyMatrices(m).Frequencies);    
    surf(Axes,CorrelatorCodePhases_,FilterFrequencies_,MultiCorrelator.EnergyMatrices(m).Matrix,MultiCorrelator.EnergyMatrices(m).Matrix,...
        'FaceColor','Interp','EdgeAlpha',0.75,'FaceAlpha',(M-m+1)/(M+1));
end

% Display of maximum
Maxima = cellfun(@(M)max(M,[],'all'),{MultiCorrelator.EnergyMatrices.Matrix});
m = find(eq(Maxima,max(Maxima)));
[i,j] = find(eq(MultiCorrelator.EnergyMatrices(m).Matrix,Maxima(m)));
text(MultiCorrelator.EnergyMatrices(m).CodePhases(j),MultiCorrelator.EnergyMatrices(m).Frequencies(i),MultiCorrelator.EnergyMatrices(m).Matrix(i,j),...
     {'Energy maximum',...
      sprintf('MultiCorrelator #%u: %+服务器托管网.fchip',j,MultiCorrelator.EnergyMatrices(m).CodePhases(j)),...
      sprintf('Filter #%u: %+.fHz',i,MultiCorrelator.EnergyMatrices(m).Frequencies(i)),...      
      'downarrow'},...
     'HorizontalAlignment','center',...
     'VerticalAlignment',  'bottom');

% Display of informations
view(Axes,-30,30);
T = [MultiCorrelator.EnergyMatrices(:).IntegrationTime];
title({'Energy matrices',...
         sprintf('(%u matrices x %u filters x %u correlators,',...
                  numel(MultiCorrelator.EnergyMatrices),...
                  numel(MultiCorrelator.EnergyMatrices(1).Frequencies),...
                  numel(MultiCorrelator.EnergyMatrices(1).CodePhases)),...
         sprintf('integration period: %s %sms)',num2str(1e3*T(1:end-1),'%.f, '),num2str(1e3*T(end),'%.f'))});
xlabel('Code phase [chip]');
ylabel('Frequency [Hz]');
zlabel(sprintf('Energy - PRN%u',PRN));

% Colorbar
Map = hsv;
Map = Map(1:find(diff(Map(:,1))>0,1,'first'),:);
Map = [Map;0 0 1];
colormap(fliplr(Map));
Colorbar = colorbar;
Colorbar.Label.String = 'Energy';
Colorbar.Location = 'EastOutside';

% Display of maxima
Axes(2) = subplot(4,1,4,'Parent',Figure,'NextPlot','Add','Box','on','Xgrid','on','Ygrid','on');
plot(Axes(2),1e3*T,Maxima,'.-');
set(Axes(2),'Xlim',[min(1e3*T) max(1e3*T)]);
title('Energy maximum vs non-coherent integration period')
xlabel('Non-coherent integration period [ms]');
ylabel('Energy maximum');

% Update of axes
set([Axes';findall(Axes,'type','text')],'fontsize',9);

% Main title
sgtitle('Energy matrices and non-coherent integration period',...
        'FontSize',11,'FontWeight','Bold');

% Maximization of figure
Figure.WindowState = 'maximized';