1. 1 Department of Physics Department of Electronic Engineering A Snapshot of Propagation Characteristics Observed by TIGER P. L. Dyson, R. J. Norman, M. L. Parkinson Department of Physics La Trobe University J. C. Devlin Department of Electronic Engineering La Trobe University J. A. Bennett Department of Electrical & Computer Systems Engineering Monash University

2. 2 OIS VIS (After UMLowell) (from McNamara, 1991) Vertical Sounding

3. 3 OIS VIS (After UMLowell) Ionospheric backscatter 0.5 hop B B B Ionospheric backscatter 1.5 hops 1 hop ground or sea backscatter Magnetic field lines Oblique Sounding

4. 4 E F1 F2 Leading Edge Backscatter Sounding

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6. 6 TIGER Tasmania TIGER New Zealand Geomagnetic Pole Geographic Pole TIGER Oblique Backscatter Ionograms Beam 4 8-20 MHz Scan Time of 6 min Repeat every 15 min 19-20 Feb 2000

7. 7 E F1 F2

8. 8 E F1 E F2

9. 9 Antenna Patterns Plus Thresholding dB

10. 10 Deg

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