Inclined Geosynchronous Orbit (IGSO)

Same altitude as GEO but tilted — traces a figure-8 ground track over a single longitude.

IGSO has the same 24-hour period as GEO but at an inclined orbital plane. The result: from the ground, the satellite traces a figure-8 pattern over a single longitude. China's BeiDou IGSO segment and Japan's QZSS Quasi-Zenith system use this to provide enhanced coverage at high latitudes where pure GEO performs poorly.

Examples

• USA 170
• QZS-1R (QZSS/PRN 196)
• BEIDOU-2 IGSO-3 (C08)
• QZS-2 (QZSS/PRN 194)
• BEIDOU-3 IGSO-1 (C38)
• USA 149 (DSP 20)
• SHIYAN-9 (SY-9)
• BEIDOU-2 IGSO-4 (C09)
• TDRS 6
• IRNSS-1E
• LUDI TANCE-4 01A
• BEIDOU-3S IGSO-1S (C31)
• INMARSAT 3-F3
• USA 164 (MILSTAR-2 3)
• BEIDOU-3 IGSO-3 (C40)
• INMARSAT 3-F1
• IRNSS-1A
• USA 99 (MILSTAR-1 1)
• USA 169 (MILSTAR-2 4)
• IRNSS-1I
• TDRS 7
• USA 134
• LUCH 5B (SDCM/PRN 125)
• SHIYAN-29