function settings = initSettings_IQ()
%Functions initializes and saves settings. Settings can be edited inside of
%the function, updated from the command line or updated using a dedicated
%GUI - "setSettings".  
%
%All settings are described inside function code.r
%
%settings = initSettings()
%
%   Inputs: none
%
%   Outputs:
%       settings     - Receiver settings (a structure). 

%--------------------------------------------------------------------------
%                           SoftGNSS v3.0
% 
% Copyright (C) Darius Plausinaitis
% Written by Darius Plausinaitis
%--------------------------------------------------------------------------
%This program is free software; you can redistribute it and/or
%modify it under the terms of the GNU General Public License
%as published by the Free Software Foundation; either version 2
%of the License, or (at your option) any later version.
%
%This program is distributed in the hope that it will be useful,
%but WITHOUT ANY WARRANTY; without even the implied warranty of
%MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
%GNU General Public License for more details.
%
%You should have received a copy of the GNU General Public License
%along with this program; if not, write to the Free Software
%Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
%USA.
%--------------------------------------------------------------------------
%% Optional Parameters
% Number of milliseconds to be processed used 36000 + any transients (see
% below - in Nav parameters) to ensure nav subframes are provided
settings.msToProcess        = 5*1e3;        %[ms]
% Move the starting point of processing.
settings.skipNumberOfBytes  = 0*2.046e9; %0*2.046e6; %0*2.046e6;%1.5*4.092e6*2; % settings.samplingFreq;%13169313;%settings.samplingFreq/5*4;%+16e3*50;%16e3*100.;
% The notch bandwidth of filter
settings.Brej = 5e3;
settings.fileName = 'D:\Long\NAVIS\Data\2023-12-20.bin';
%settings.fileName = 'E:\TEXBAT\cleanDynamic_spoofing.bin';
%settings.fileName ='K:\DATA\Projects\SDR\gnss-sdr-sim\vs-gps-sdr-sim\vs-gps-sdr-sim\x64\Debug\gpssim.bin';'D:\test_4093.bin';'D:\RTL2832U_Data\test_1.bin';'D:\test.bin';['C:\rtldata\test_0.bin'];%['C:\Users\thuan\Downloads\sdrsharp-x86\SDRSharp_20151223_155844Z_1575420000Hz_IQ.wav'];%
% settings.fileName = ['D:\IF_DATA\RTL2832\140320_1243_1.dat'];
settings.relativeFreq   = 0;
%% Independent parameters 
% Number of channels to be used for signal processing
settings.numberOfChannels   = 5;
% Intermediate, sampling and code frequencies
settings.IF             = 0e3;      %[Hz]               tần số trung gian
settings.samplingFreq   = 2e6; %2.5e7; %2e6; 2.6e6; 8184000;    [Hz]    tần số lấy mẫu
settings.codeFreqBasis  = 1.023e6;      %[Hz]           tần số mã
% Define number of chips in a code period
settings.codeLength     = 1023;                         % số lượng chip trong 1 chu kỳ mã
settings.samplesPDI     = settings.samplingFreq*10e-3;
% Number of samples per spreading code
settings.samplesPerCode = round(settings.samplingFreq / ...
    (settings.codeFreqBasis / settings.codeLength));
settings.dataType       = 'int16';
if strcmp(settings.dataType,'int8')
    settings.dataTypeSize   =  1;
else
    settings.dataTypeSize   =  2;
end;
%% Acquisition settings ===================================================
% Skips acquisition in the script postProcessing.m if set to 1
settings.skipAcquisition    = 2e6;
% List of satellites to look for. Some satellites can be excluded to speed
% up acquisition
settings.acqSatelliteList   = 1:32;         %[PRN numbers]
% Band around IF to search for satellite signal. Depends on max Doppler
settings.acqSearchBand      = 10;           %[kHz]
% Threshold for the signal presence decision rule
settings.acqThreshold       = 2.4;

%% Tracking loops settings ================================================
% Code tracking loop parameters
settings.dllDampingRatio         = 0.7;
settings.dllNoiseBandwidth       = 2;       %[Hz] 2
settings.dllCorrelatorSpacing    = 0.5;     %[chips]
% Carrier tracking loop parameters
settings.pllDampingRatio         = 0.7;
settings.pllNoiseBandwidth       = 25;      %[Hz] 25

%% Navigation solution settings ===========================================
% Period for calculating pseudoranges and position
settings.navSolPeriod   = 100;      %[ms]
% Elevation mask to exclude signals from satellites at low elevation
settings.elevationMask  = 10;       %[degrees 0 - 90]
% Enable/disable use of tropospheric correction
settings.useTropCorr    = 1;        % 0 - Off
                                    % 1 - On
% True position of the antenna in UTM system (if known). Otherwise enter
% all NaN's and mean position will be used as a reference .
settings.truePosition.E = nan;
settings.truePosition.N = nan;
settings.truePosition.U = nan;

%% Plot settings ==========================================================
% Enable/disable plotting of the tracking results for each channel
settings.plotTracking       = 1;            % 0 - Off
                                            % 1 - On
settings.plotAcquisition    = 1;

%% Constants ==============================================================
settings.c                  = 299792458;    % The speed of light, [m/s]
settings.startOffset        = 68.802;       %[ms] Initial sign. travel time