1. ARL Applied Research Laboratories The University of Texas at Austin ARL Applied Research Laboratories The University of Texas at Austin Ionospheric Tomography Network of Egypt T W Garner Applied Research Laboratories University of Texas at Austin A M Mahrous Space Weather Monitoring Center Helwan University

2. ARL Applied Research Laboratories The University of Texas at Austin Ionospheric Tomography Network of Egypt Chain of 3 CIDRs in Egypt as part of ISWI Only 1 is operational right now Located at different university campuses across Egypt. Operated jointly by Helwan University (Ayman Mahrous) and ARL:UT (Trevor Garner)

3. ARL Applied Research Laboratories The University of Texas at Austin UHF/VHF Satellite Radio Beacons  Transit-  First satellite navigation system  Satellites in LEO (~1000 km), polar orbit  Transmitted navigation message at 150 and 400 MHz  Doppler shift of the signals used for positioning  Decommissioned in 1989 to the Navy Ionospheric Monitoring System (NIMS)  4 Active beacons  Other US Radio Beacons-  Several DoD missions have flown a NRL-developed radio beacon  C/NOFS, DMSP F15, Radcal  Several other nations have flown or will fly radio beacons  COSMIC, ePoP, future Brazilian and Indian missions

4. Coherent Ionospheric Doppler Receivers (CIDRs)  Designed to track 150/400MHz LEO beacons (Transit/NIMS, GFO)  Provides relative TEC and phase scintillation measurements  Useful for examining spatial structure with a relatively sparse receiver network and conducting ionospheric tomography 30 meter RF cable 150 MHz 400 MHz PCRX

5. ARL Applied Research Laboratories The University of Texas at Austin CIDR measurements  Doppler shift in both the 150 and 400 MHz channels  Linear combinations of these two Doppler shifts produce three separate ionospheric measurements  STEC/  t  Ionospheric δf at 150 MHz  Ionospheric δf at 400 MHz  The  STEC/  t can be integrated to a STEC under the satellite  All three measurements can be binned and RMS values used to characterize the scintillation

6. ARL Applied Research Laboratories The University of Texas at Austin Ionospheric Doppler Shift

7. ARL Applied Research Laboratories The University of Texas at Austin Dual Frequency Combinations  Most existing UHF/VHF beacons transmit at 8/3  There are 2 basic linear combinations for dual frequency Doppler measurements

8. ARL Applied Research Laboratories The University of Texas at Austin Scale of CIDR measurements  For a typical beacon satellite orbit, the satellite crosses a full field of view in 20 minutes.  Corresponds to an arc distance of ~0.15 o in 1 second  The CIDR are sensitive to smaller-scale structures  At 1 Hz: F-region structures (300 km) ~1570 m E-region structures (100 km) ~525 m  Limited by the Fresnel Scale F-region Fresnel Scale ~ 774.5 m E-region Fresnel Scale ~ 447.2 m 

9. ARL Applied Research Laboratories The University of Texas at Austin Features of UHF/VHF Beacon Electron Content Measurements  Spacecraft cross the field of view in ~20 min (GPS spacecraft take ~8hrs)  Enable tomographic reconstruction  Measurements from LEO spacecraft (~1000 km)  Purely ionospheric measurement  Shorter frequencies (400 MHz vrs 1575.42 MHz)  More precise TEC measurements  TEC ~  /f 2  CIDR ~ 15.5 more precise than GPS

10. ARL Applied Research Laboratories The University of Texas at Austin More Differences Between GPS and CIDRs  Tend to have a higher data rates  1 kHz decimated to 1-10 Hz  Allows measurements of the rapid ionospheric variations  Relative TEC measurements  Relative to an unknown integration constant  GPS TEC relative unknown transmitter and receiver biases

11. ARL Applied Research Laboratories The University of Texas at Austin CIDR Data Chain  Receiver records the raw Doppler measurements  Postprocessing code quality checks the Doppler measurements, calculates the positioning solutions, and converts the Doppler measurements to  TEC/  t and TEC

12. Sample Doppler File # 2629.864331.31780.83 # 1907188510Operational1 # 2008 299 17 33 36.000000 # 2008 299 17 48 21.000000 63216.19710.06377.1013197.6597.52226.836542.449797.69498.127 63217.19710.06587.1007397.42697.47926.842242.442297.58197.832 63218.19710.0687.1008597.87897.81226.847942.368397.69197.24 63219.19710.07017.2755897.55797.38926.853641.903797.65398.373 63220.19710.07227.9377598.10398.18926.859340.124697.44697.387 63221.19710.07448.1000197.43898.37226.86537.94298.40797.116 63222.19710.07658.1674197.46697.79726.870835.696797.71897.86 63223.19710.07878.2462498.14197.94926.876633.39397.70196.813 63224.19710.08098.3211698.0497.626.882431.64497.52998.165 63225.19710.08318.3949898.11498.02426.888231.394497.26397.765 63226.19710.08528.4651497.79797.826.89431.22397.79897.526 63227.19710.08758.5430897.43698.12126.899931.054598.3397.998 63228.19710.08978.6200297.74896.93826.905830.880997.91998.108 63229.19710.09198.7021798.11397.2526.911730.707597.74397.568 63230.19710.09418.7795497.85298.08226.917630.529497.08298.004 63231.19710.09638.8559997.78297.56926.923530.347797.38497.839 63232.19710.09868.9295998.00898.51826.929530.165597.24497.611 63233.19710.10089.0029697.70197.96926.935530.003198.07497.477 63234.19710.10319.0825198.25596.87126.941529.827497.15897.812 63235.19710.10539.1626897.10298.32326.947529.647697.73798.143 63236.19710.10769.2354197.40598.08126.953629.467697.75397.742 63237.19710.10999.3123297.26997.46126.959729.292197.72797.911 63238.19710.11229.3898797.55797.73326.965829.123697.73497.076 63239.19710.11459.4673297.84398.63926.971928.963196.9897.191

13. Sample Processed Text File # GLOBAL ATTRIBUTES -- name : value CONTACT : Trevor Garner, ARL:UT, garner@arlut.utexas.edu CREATOR : Kanish Mehta SOURCE : Applied Research Laboratories: University of Texas at Austin instrument : ARL:UT CIDR Receiver # 26 receiver_location : Helwan receiver_latitude : 29.8643 receiver_longitude : 31.317 receiver_altitude : 80.83 sample_rate_hz : 1 satellite_name : OSCAR 32 num_data : 643 # UT Relative TEC Rate Sat.Lat Sat.Lon Sat.Alt Azimuth Elevation F Lat F Long E Lat E Lon Phase Rate Phase Rate Sat.Vel Good # (sec) TEC (TECU) (TECU/1.00s) (deg) (deg) (km) (deg) (deg) (deg) (deg) (deg) (deg) VHF (Hz) UHF (Hz) (km/s) Flag 63278.2 3.0654 -0.0308161 52.2703 61.5188 1299.31 36.0752 2.37675 41.4956 43.0712 35.797 36.7374 10.6 27.5 20.5309 1 63279.2 3.07675 0.0113533 52.217 61.514 1299.23 36.1573 2.4098 41.4602 43.0659 35.7708 36.7281 10.2 27.5 20.6618 1 63280.2 3.07026 -0.00648761 52.1636 61.5092 1299.16 36.2396 2.44283 41.4248 43.0606 35.7447 36.7189 10.4 27.5 20.5964 1 63281.2 3.07675 0.00648761 52.1103 61.5044 1299.09 36.322 2.47583 41.3895 43.0553 35.7187 36.7097 10.3 27.7 20.8036 1 63282.2 3.04269 -0.0340599 52.0569 61.4996 1299.01 36.4045 2.50881 41.3542 43.05 35.6928 36.7005 10.5 27.4 20.4764 1 63283.2 3.04755 0.00486571 52.0036 61.4948 1298.94 36.4872 2.54178 41.319 43.0447 35.6671 36.6914 10.3 27.4 20.5418 1 63284.2 3.03458 -0.0129752 51.9502 61.4901 1298.86 36.5701 2.57472 41.2839 43.0394 35.6414 36.6823 10.4 27.4 20.5091 1 63285.2 3.05242 0.0178409 51.8969 61.4853 1298.79 36.6531 2.60763 41.2489 43.0341 35.6159 36.6732 10.2 27.5 20.6618 1 63286.2 3.04431 -0.00810951 51.8435 61.4805 1298.71 36.7362 2.64053 41.2139 43.0288 35.5904 36.6642 10.4 27.5 20.5964 1 63287.2 3.0362 -0.00810951 51.7902 61.4757 1298.64 36.8195 2.6734 41.1789 43.0236 35.5651 36.6552 10.4 27.5 20.5964 1 63288.2 3.04593 0.00973141 51.7368 61.4709 1298.56 36.9029 2.70625 41.1441 43.0183 35.5399 36.6462 10.2 27.5 20.6618 1 63289.2 3.02971 -0.016219 51.6835 61.4662 1298.49 36.9865 2.73908 41.1092 43.0131 35.5148 36.6373 10.4 27.4 20.5091 1 63290.2 3.02323 -0.00648761 51.6301 61.4614 1298.41 37.0702 2.77188 41.0745 43.0079 35.4898 36.6285 10.4 27.5 20.5964 1 63291.2 3.0216 -0.0016219 51.5768 61.4566 1298.34 37.1541 2.80466 41.0398 43.0026 35.465 36.6196 10.3 27.5 20.6291 1 63292.2 3.02971 0.00810951 51.5234 61.4518 1298.26 37.2381 2.83741 41.0052 42.9974 35.4402 36.6108 10.2 27.5 20.6618 1 63293.2 3.0216 -0.00810951 51.4701 61.4471 1298.18 37.3223 2.87015 40.9706 42.9922 35.4155 36.602 10.4 27.5 20.5964 1 63294.2 3.00538 -0.016219 51.4167 61.4423 1298.11 37.4066 2.90285 40.9362 42.9871 35.391 36.5933 10.4 27.4 20.5091 1 63295.2 2.99565 -0.00973141 51.3633 61.4375 1298.03 37.491 2.93553 40.9017 42.9819 35.3665 36.5846 10.4 27.6 20.6836 1 63296.2 2.9989 0.0032438 51.31 61.4328 1297.96 37.5757 2.96819 40.8674 42.9767 35.3422 36.576 10.2 27.3 20.4873 1 63297.2 2.98268 -0.016219 51.2566 61.428 1297.88 37.6604 3.00082 40.8331 42.9716 35.318 36.5674 10.4 27.4 20.5091 1 63298.2 2.96808 -0.0145971 51.2033 61.4232 1297.8 37.7453 3.03343 40.7988 42.9664 35.2938 36.5588 10.4 27.4 20.5091 1 63299.2 2.95511 -0.0129752 51.1499 61.4185 1297.73 37.8304 3.06601 40.7646 42.9613 35.2698 36.5503 10.4 27.4 20.5091 1 63300.2 2.94862 -0.00648761 51.0965 61.4137 1297.65 37.9156 3.09856 40.7305 42.9562 35.2459 36.5418 10.3 27.4 20.5418 1 63301.2 2.93564 -0.0129752 51.0432 61.4089 1297.57 38.0009 3.13109 40.6965 42.9511 35.2221 36.5333 10.4 27.5 20.5964 1 63302.2 2.92916 -0.00648761 50.9898 61.4042 1297.5 38.0864 3.1636 40.6625 42.946 35.1984 36.5249 10.3 27.4 20.5418 1 63303.2 2.91131 -0.0178409 50.9364 61.3994 1297.42 38.1721 3.19607 40.6285 42.9409 35.1748 36.5165 10.4 27.3 20.4218 1 63304.2 2.90483 -0.00648761 50.883 61.3947 1297.34 38.2579 3.22852 40.5947 42.9358 35.1513 36.5081 10.3 27.3 20.4545 1 63305.2 2.89672 -0.00810951 50.8297 61.3899 1297.26 38.3438 3.26094 40.5609 42.9308 35.1279 36.4998 10.3 27.3 20.4545 1

14. ARL Applied Research Laboratories The University of Texas at Austin Sample ITNE Observation

15. ARL Applied Research Laboratories The University of Texas at Austin ITNE Science Goals  Large-scale plasma structures  Chain is located underneath of equatorial fountain peaks (15.6 to 23.8 deg magnetic latitude)  Routine observations of the equatorial fountain peaks  Tomography and data assimilative reconstructions of the fountain  Small-scale plasma irregularities  TEC variations associated with equatorial anomaly peaks  Examine the consequence with tropospheric weather  Comparison with the American sector CIDR chain  Examine the impact of greater geographic/magnetic latitude offsets in the Americas

16. ARL Applied Research Laboratories The University of Texas at Austin Analysis of Sample Observation

17. Ionospheric Tomography  Traditional usage of the CIDR-like measurements  Utilizes crossing ray paths  Typically 3-5 receivers along aligned with the orbit  Assumes a slowly varying ionosphere  Typically 15 minute time steps

18. ARL Applied Research Laboratories The University of Texas at Austin Contact Information  If you are interested in working with ITNE data, please contact:  Ayman Mahrous (ayman.mahrous@gmail.com)  Trevor Garner (garner@arlut.utexas.edu)

19. ARL Applied Research Laboratories The University of Texas at Austin Summary  First ITNE CIDR is up and running  First results of Coherent Ionospheric Doppler Receiver measurements over Egypt, Mahrous, A., A. Shimeis, and T. Garner, Space Weather, 8, doi:10.1029/2009SW000548, 2010.  Excellent opportunity to study the northern crest of equatorial fountain in Africa  Please contact garner@arlut.utexas.edu or ayman.mahrous@gmail.com if you think ITNE data can help in your data study.