SGO Ionospheric Tomography Description

Sodankylä Geophysical Observatory

Ionospheric Tomography


SGO tomography chain: A chain of five satellite receivers observed signals from the Russian Low Earth Orbit (LEO) satellites. Two signals transmitted coherently at frequencies 150 MHz and 400 MHz are received and the phase difference is used to calculate the ionospheric electron density by means of statistical inversion. The results are shown in terms of electron density plots in a vertical plane above the receiver chain. In an ideal case the satellite flies along the chain. If this is not the case, the plot is a projection from regions outside the vertical plane. In order to estimate the validity of the results, check the satellite path in each case.  

Method (pdf)

Some references

Nygren, T., M. Markkanen, M. Lehtinen, E. D. Tereshchenko, B. Z. Khudukon, Stochastic inversion in ionospheric radiotomography, Radio Science, 32, 2359-2372, 1997.
Norberg, J., Roininen, L., Kero, A., Raita, T., Ulich, T., Markkanen, M., Juusola, L., and Kauristie, K.: Sodankylä ionospheric tomography dataset 2003-2014, Geosci. Instrum. Method. Data Syst. Discuss., 5, 385-404,
doi:10.5194/gid-5-385-2015, 2015.

Used satellites/transmitters:

The SGO first receivers were capable to receive only Russian LEO satellites called as Tsykada. Codes presented on the main page response planes of the satellites. Here are details of the satellites used:

Codes/planes in telemetry data USSPACECOM code Int. code Satellite
101/103/106 28380 2004-028-A COSMOS 2407
102 27818 2003-023-A COSMOS 2398
103 35635 2009-039-A COSMOS 2454
104 28521 2005-002-A COSMOS 2414
105 32052
(COSMOS 2361)
106 36519
(COSMOS 2378)
Sample of COSMOS 2407 transmission can be found from YouTube.

Operation of the chain: Continuous operation started on January 1, 2003. Satellite schedules updated weekly, reconstruction calculated monthly. Raw data can be stored by request. Amplitude and phase differecence updated once per hour to LatestData page.

Receiver sites of old SGO tomography chain and the hosts:

Tromsø (TRO: 69.66°N, 18.94°E, L=6.5): 2002-2004
The Auroral Observatory
, University of Tromsø, Norway

Kilpisjärvi (KIL: 69.02°N, 20.86°E, L=6.1): 2004-2013
SGO's site station, Kilpisjärvi, Finland

Kiruna (KIR: 67.84°N, 20.41°E, L=5.6): 2002-2017
Swedish Institute of Space Physics (IRF)
, Kiruna, Sweden

Luleå (LUL: 65.58° N, 22.17°E, L=4.7): 2002-2015
Luleå University of Technology
, Luleå, Sweden

Kokkola (KOK: 63.83°N, 23.06°E, L=4.2): 2004-2017
Keski-Pohjanmaan Ammattikorkeakoulu, Tekniikan yksikkö
, Kokkola, Finland 

Nurmijärvi (NUR: 60.51°N, 24.65°E, L=3.4):2004-2017
Finnish Meteorological Institute, Nurmijärvi Geophysical Observatory
, Nurmijärvi, Finland 

L-value of stations checked from VITMO ModelWeb (IGRF-11, 2010, altitude 100km).

Last modified: 27 August 2019, 09:06:23.

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