GLONASSGlobalnaya Navigatsionnaya Sputnikovaya Sistema

GLONASS is Russia's GNSS, operated by Roscosmos. The constellation maintains 24 satellites in three 64.8°-inclined orbital planes at 19,100 km altitude. The higher inclination provides notably better high-latitude coverage than GPS — relevant for users in Russia, Scandinavia, and the polar regions.

GLONASS's distinctive feature is its legacy FDMA channelisation: each satellite broadcasts on a slightly different centre frequency (L1 channels at 1602 MHz + k × 0.5625 MHz, L2 at 1246 MHz + k × 0.4375 MHz, with k = −7 to +6). This means an antenna for GLONASS L1/L2 needs roughly ±7 MHz of bandwidth around each centre — wider than the single-frequency GPS bands.

Newer GLONASS satellites also broadcast CDMA signals (L1OC at 1600.995 MHz, L2OC at 1248.06 MHz, L3OC at 1202.025 MHz) that follow the same one-carrier-per-system convention as GPS / Galileo / BeiDou. These modernised signals simplify receiver design and improve interoperability.

For multi-constellation tracking, almost every modern GNSS antenna supports GLONASS L1+L2 alongside GPS L1+L2 — they're close enough in frequency that a single wideband patch element with proper LNA can cover both.