Beyond GPS: What Other Global Navigation Satellite Systems Exist?
When people think of satellite navigation, GPS is often the first—and sometimes the only—system that comes to mind. In reality, GPS is just one part of a much larger global positioning infrastructure known as GNSS.
Today, multiple satellite navigation systems operate around the world, working together to provide accurate positioning, navigation, and timing services—no matter where you are.
So what other Global Navigation Satellite Systems exist besides GPS, and why do they matter? Let’s take a closer look.
1. What Is GNSS?
A Global Navigation Satellite System (GNSS) is a network of satellites orbiting Earth that transmit signals to receivers on the ground. By calculating how long these signals take to reach the receiver, the device can determine its position, velocity, and precise time.
Today, multiple GNSS constellations are in operation around the world. Each system is independently managed, but modern receivers are designed to use signals from several systems simultaneously, improving accuracy, reliability, and availability—especially in challenging environments such as urban areas or mountainous regions.
Below is an overview of the major GNSS systems currently in use:
| System | Country/Region | Satellites | Key Features | Positioning Accuracy |
|---|---|---|---|---|
| GPS | USA | 31+ | Global coverage, mature technology | 1–5 m (civilian) |
| BeiDou (BDS) | China | 35+ | Short Message Service (unique global capability), Asia-Pacific enhancement | ~1 m (Asia-Pacific), ~3 m (global) |
| GLONASS | Russia | 24+ | Optimized for high-latitude regions | 2-8 meters |
| Galileo | Europe | 26+ | High-accuracy civil service, SAR return link | ~1 m (civilian) |
| QZSS | Japan | 4+ | Augments Asia-Pacific coverage (urban canyon enhancement) | Centimeter-level (with augmentation) |
| IRNSS/NavIC | India | 7+ | Regional coverage (India and surroundings) | 1–3 m (India) |
2. Introduction to GNSS Frequencies
In addition to multiple satellite systems, GNSS positioning also relies on signal frequencies. Each GNSS constellation transmits signals on specific frequency bands, and modern receivers can track multiple frequencies at the same time to improve accuracy and reliability.
BeiDou (BDS)
- BDS-2: B1I, B2I, B3I
- BDS-3: B1C, B2a, B2b, B3I
GPS
- L1, L2, L5
L1 is the most common, used by almost all GNSS receivers, and L2 and L5 are for more accurate positioning.
GLONASS
- G1, G2, G3
G1 and G2 are used for regular signals, while G3 represents GLONASS's newer CDMA signals alongside traditional FDMA signals.
Galileo
- E1, E5, E6
These help Galileo satellites give you precise location information.
QZSS
- L1, L2, L5, L6
Improves satellite availability and positioning performance in Japan’s dense urban environments.
IRNSS / NavIC
- L5 and S-band
Provides reliable regional navigation services for India and nearby regions.
3. GNSS Beyond GPS: One Global System Working Together
While GPS may be the most well-known system, today’s positioning technology relies on a global collaboration of satellite constellations. Together, they form the backbone of modern navigation—supporting everything from smartphone maps to industrial-grade automation.
As GNSS technology continues to evolve, the combination of multiple systems and frequencies will play an increasingly important role in delivering the accuracy and reliability that modern applications demand.
Recommended Reading
For a deeper look at how GNSS positioning works, you may also enjoy “How Satellite Navigation Systems Know Exactly Where You Are.” The article explains the core principles behind satellite navigation, from signal timing to position calculation.