#
## Copyright (c) 1995-2020 University Corporation for Atmospheric Research
## All rights reserved
#
my $pkgdoc = <<'EOD';
#/**----------------------------------------------------------------------
# @file       BJConstants.pm
# Constants for use in routines that process BlackJack type data
#
# @author     Doug Hunt
# @since      10/27/2008
# @version    $URL: svn://svn1.cosmic.ucar.edu/trunk/src/BJutils/BJConstants.pm $ $Id: BJConstants.pm 24769 2019-06-05 14:18:52Z dhunt $
# cdaacTask   no
# -----------------------------------------------------------------------*/
EOD

package BJConstants;

use Config;

require Exporter;
our @ISA = qw(Exporter);
our @EXPORT = qw(
                  $PI $CLIGHT $F1 $F2 $B1 $B2 $E1 $E6 $E5 $E5a $E5b $LAMB1 $LAMB2 $SNRCONV50 $SNRCONV50Paz $SNRCONV100 $L1_L2 $L2_L1 $RAD2CYC $RAD2DEG $DEG2RAD $BIGENDIAN %CONSTELLATION_MAP
              );

# Conversion factors
$PI        = 4*atan2(1,1);
$CLIGHT    = 299792458;   # speed of light, meters/sec
$F1        = 1575.42e6;   # L1 frequency, Hz
$F2        = 1227.60e6;   # L2 frequency, Hz

# Found in BeiDou Navigation Satellite System Signal In Space Interface Control Document Open Service Signal (Version 2.0), Dec. 2013
$B1        = 1561.098e6;  # B1 frequency (Beidou), Hz
$B2        = 1207.140e6;  # B2 frequency (Beidou), Hz

# Found in the Galileo Open Service Signal In Space ICD, version 1.2 Nov. 2015
$E1  = 1575.420e6;
$E6  = 1278.750e6;
$E5  = 1191.795e6;
$E5a = 1176.450e6;
$E5b = 1207.140e6;

$LAMB1     = $CLIGHT/$F1; # L1 wavelength, meters
$LAMB2     = $CLIGHT/$F2; # L2 wavelength, meters
$SNRCONV50 = 50.0 * 4.0 / sqrt(20.456e6 * .75 * .9 * 2.0); # Conversion:  amplitude -> SNR (v/v) # 20.456e6 is the internal sampling frequency
$SNRCONV50Paz = 50.0 * 4.0 / sqrt(19328000 * .75 * .9 * 2.0); # Conversion:  amplitude -> SNR (v/v) # 19328000 is the internal sampling frequency for Paz
$SNRCONV100 = 100.0 * 4.0 / sqrt(20.456e6 * .75 * .9 * 2.0); # Conversion:  amplitude -> SNR (v/v) ??? A guess
$L1_L2     = $F2/$F1;     # Convert L1 cycles to L2 cycles
$L2_L1     = $F1/$F2;     # Convert L2 cycles to L1 cycles
$RAD2CYC   = 1.0/(2.0*$PI); # Convert radians to cycles
$RAD2DEG   = 180/$PI;
$DEG2RAD   = $PI/180;

my $BIGENDIAN = ($Config{'byteorder'} =~ /4321/);

# Bernese convention:  add 100 to PRN number for GLONASS, 200 for Galileo, 300 for SBAS
# 400 for Beidou and 500 for QZSS
%CONSTELLATION_MAP = (G => 0, R => 100, E => 200, S => 300, C => 400, J => 500);

1;