Observation record.Satnogs-UHF.2021-04-15T20-34-00

Ground-station Satnogs-UHF
Owner N5CNB

Waterfall
DopplerComparaison
PostProcessing

Résumé de l'événement

satellite LUSAT_(LO-19)
date 2021-04-15
time 20:34:00
duration 600
freq 4.37125e+08
culm 76.4188

Waterfall

The graph at the bottom left gives the waterfall (time on the abscissa, frequency on the ordinate). The graph at the top gives the integrated signal strength in frequency as a function of time. At the bottom right, the average of the spectra over all the measurement times (frequency on the ordinate).

The time range of the measurement is given in the top right part (minimum_time, maximum_time). The frequency range determined by the number of points used by the Fourier transform is given by fmin and fmax. The units used for power (or the energy received in each time slot) could not be determined.

transitfile record.Satnogs-UHF.2021-04-15T20-34-00.transit

Additional capture data

The beginning of the transit is marked by a circle and the end of the transit by a disc.

• paramètres prévus
  filename record.Satnogs-UHF.2021-04-15T20-34-00
  satellite LUSAT_(LO-19)
  date 2021-04-15
  time 20:34:00
  samp 250000
  duration 600
  freq 4.37125e+08
  culm 76.4188
• paramètres réalisés
  recfile record.Satnogs-UHF.2021-04-15T20-34-00.dat
  start 2021-04-15T20:34:00
  end 2021-04-15T20:44:02
  freq 4.37125e+08
  gain 48
  ns 600
  samp 250000
  nsamp 150000000

Gaussian fit

When the intensity of the signal as a function of time follows an approximately Gaussian law, this tool must capture approximately the parameters by non-linear adjustment. The adjustment is carried out using the NLOPT2 library. The behavior is undefined if the law is arbitrary.

abscisses: giga-samples name ordinates: sum_20000(I²+Q²)/1e6

• Resultats du fit
  t0 500000 [ 2 s]
  a 1000
  sigma 1500000
  y0 2000

calpower-stats

• Autres statistiques (de la valeur I²+Q²)
  moyenne 8.66451
  max 15.3844
  moyenne.debut.fin 7.36472
  hauteur.signal 8.01965 [ 9.04155 dB ] (max - moyenne.debut.fin)
  longueur.totale 600
  integrale.signal 779.872 (somme - moyenne.debut.fin*longueur.totale)

Calculated and measured Doppler comparison

Abscissa: frequency in Hz
Ordinates: time in seconds

sumY2 8.76898e+13
sumDy2 1.4409e+12
dfmin 749.755 sumDy2 3.75909e+10
dtmin 0.170632 sumDy2 3.7326e+10

* Kepler element data for LUSAT_(LO-19)

name ‘LUSAT_(LO-19)’
satellite_number 20442
central_object EARTH
ephemeris_type UnknownEphemerisType
epoch_year 21
epoch_day 104.45840881

• Kepler elements
  epoch_julday 2459318.95840881
  Time jd 2459318.95841 < 2021-04-14 11:00:06.0521 UTC >
  inclination 98.7352 deg [98 44'07"]
  right_ascension_of_ascending_node 59.3647 deg [3:57:28]
  major_radius 7160.73 km
  eccentricity 0.001167
  periast_argument 355.082 deg [355 04'54"]
  mean_anomaly 5.025 deg [5 01'30"]

• Supplemental data
  cc 1.9976687206
  ra 7.16909e+06 [798077]
  rp 7.15237e+06 [781364]
  va 7470.87
  vp 7453.45
  axb 7169.09 x 7169.08
  mammmdt 51.6658
  bstar 0.6647
  mean_motion_1st_deriv 0
  mean_motion_2nd_deriv 0
  mean_motion 14.3298 rev/day 0.0697845 day/rev
  periapsis_distance 7152.37 km
  apoapsis_distance 7169.09 km
  periapsis_mean_height 781.364 km
  apoapsis_mean_height 798.077 km
  rev_number_at_epoch 63166
  tle_age 0.883327 day

* TLE

LUSAT (LO-19)
1 20442U 90005G 21104.45840881 .00000000 00000-0 16647-4 0 9990
2 20442 98.7352 59.3647 0011670 355.0817 5.0250 14.32982236631660

Spectrum analysis

median 7.52146
noise_level_db 7.63404
min -0.895084
max 39.7751
freq_center -3007.02
trig_level_db 10
nbin_rescaling 29.9957
freq_center_trig 1350.44
signal_range_dB 32.141
theo_range_dB 48.1648 [ 8 bits ]

Post-processing

number of decodings: 0

Credits

Decodage gr-satellites v3.6.0 (Daniel Estevez)

N5FXH’s page

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