- HF Doppler observation at IAP (Institute of Atmospheric Physics), Czech Republic
- HF Doppler observation at NCU (Graduate Institute of Space Science, National Central University), Taiwan
- HF Trans-equatorial Propagation Experiment at NICT (NICT), Japan
- Old HFD Project Web Archive
- Super Dual Auroral Radar Network - Japan
- Super Dual Auroral Radar Network - Virginia Tech.
- Super Dual Auroral Radar Network - Dartmouth College
- Super Dual Auroral Radar Network - Canada
- Technical document for the souding system (in Japanese)
- Ionospheric oscillations revealed by HF Doppler measurement technique