Jump to content

Global Navigation Satellite Systems

From Garmin Wiki
(Redirected from QZSS)
Global Navigation Satellite Systems
Overview
Type Navigation Technology
Availability
Devices All Garmin GPS watches

Global Navigation Satellite Systems (GNSS) is the technology that enables Garmin watches to track your location, calculate pace and distance, map routes, and provide navigation for outdoor activities. Whether you're running, hiking, cycling, or exploring trails, GNSS is what allows your watch to know where you are and where you've been. While most people commonly refer to "GPS" when talking about satellite navigation, GPS is actually just one of several satellite constellations that modern Garmin watches can utilize. Garmin often uses "GPS" and "GNSS" interchangeably in marketing materials, and most Garmin watches are marketed as "GPS smartwatches" even though they support multiple satellite systems.[1]

Modern Garmin watches typically support multiple GNSS constellations simultaneously—a mode often called "All Systems" or "All Satellite Systems" in Garmin's settings. This "All Systems" mode connects to satellites from GPS, GLONASS, Galileo, and other constellations at once, enabling more accurate and reliable positioning than using a single system alone, especially in challenging environments like urban canyons or dense forests.[2]

Understanding GPS vs. GNSS

The terms "GPS" and "GNSS" are often used interchangeably, but they have distinct meanings. GPS (Global Positioning System) is a specific satellite navigation system operated by the United States—it was the first operational GNSS and remains the most widely known. GNSS (Global Navigation Satellite Systems) is the generic term encompassing all satellite navigation systems worldwide.

The major GNSS constellations include:

  • GPS (United States) – 31 satellites, global coverage, the original and most widely supported system
  • GLONASS (Russia) – 24+ satellites, global coverage, different orbital planes than GPS for improved high-latitude accuracy
  • Galileo (European Union) – 24+ satellites, global coverage, designed as a civilian system with high accuracy
  • BeiDou (China) – 35+ satellites, global coverage with enhanced accuracy in Asia-Pacific
  • QZSS (Japan) – 5 satellites, regional coverage for Japan and Asia-Oceania, augments GPS
  • IRNSS (India) – 7 satellites, regional coverage for India, also known as NavIC

When Garmin markets a "GPS smartwatch," it typically supports multiple GNSS constellations, not just GPS. The term "GPS" has become colloquial shorthand for satellite navigation in general, similar to how "Kleenex" is used for tissues.

Multi-Band GNSS

Multi-Band GNSS (sometimes colloquially referred to as "multi-band GPS" or "dual-frequency GPS," though the technology almost always involves multiple GNSS constellations) is an advanced positioning technology that receives signals on two different frequency bands from the same satellite constellation. Multi-Band GNSS was first introduced on Garmin watches with the Fenix 7 series and Epix (Gen 2) in January 2022, and has since been included on most premium and mid-range Garmin watches. This is distinct from using multiple satellite systems ("All Systems" mode), which connects to different constellations but on a single frequency.[1]

Traditional single-frequency GNSS receivers use only the L1 frequency band. Multi-band receivers can use both L1 and L5 (or L2) frequency bands simultaneously. The key advantage is that different frequencies are affected differently by atmospheric interference and signal reflections (multipath errors). By comparing signals on two frequencies, the receiver can better identify and filter out reflected signals, correct for ionospheric delays more accurately, and achieve positioning accuracy improvements of up to 50%.[1]

Benefits of Multi-Band GNSS

The primary benefit of multi-band GNSS is significantly improved positioning accuracy in challenging environments. When satellite signals bounce off buildings, cliffs, or dense tree canopy, they create "multipath errors" that can throw off your position by several meters. Single-frequency receivers struggle to distinguish between direct signals and reflected signals, leading to erratic GPS tracks and inaccurate distance measurements.

Multi-band technology solves this problem by receiving the same satellite signal on two different frequencies. Since reflected signals are affected differently at each frequency, the receiver can compare the two and identify which signals are direct versus reflected. This results in cleaner GPS tracks, more accurate pace data, and better route recording—particularly valuable for activities like trail running, mountain hiking, and urban running where signal quality is often compromised.

The improvement is most noticeable in difficult terrain. In urban canyons with tall buildings, multi-band can reduce position errors from 10+ meters down to just 2-3 meters. In dense forests, it provides more consistent tracking rather than the "jumpy" tracks common with single-band receivers. However, in open-sky conditions like running on a track or cycling on open roads, the improvement is minimal since single-band accuracy is already excellent.

Environment Improvement
Urban canyons Significantly reduced errors from building reflections
Dense forests Better signal penetration and accuracy
Mountain terrain More reliable positioning near cliffs and valleys
Open sky Minimal improvement (single-band is usually sufficient)

Battery Life Impact

Multi-Band GNSS requires more processing power and consumes more battery than single-frequency modes. The table below shows how different satellite modes affect battery life, where "All Systems" refers to using multiple GNSS constellations (GPS, GLONASS, Galileo, etc.) on a single frequency:

Mode Battery Life Example (Fenix 7X)
GPS Only Up to 89 hours
All Systems (multiple GNSS constellations) Up to 63 hours
All Systems + Multi-Band Up to 36 hours

This represents a 20-40% reduction in battery life compared to single-band modes, which is why features like SatIQ were developed to intelligently manage when multi-band is needed.[1]

Watches with Multi-band GPS/GNSS

Compare all watches with Multi-band GPS/GNSS →

SatIQ

SatIQ (also called Auto Select in some Garmin interfaces) is Garmin's intelligent satellite mode switching technology that was introduced alongside multi-band GNSS on the Fenix 7 Sapphire series and Epix (Gen 2) Sapphire editions in January 2022. It has since been added to other multi-band capable watches including Forerunner 255, Forerunner 955, Enduro 2, and subsequent models. SatIQ automatically toggles between single-frequency and multi-band GNSS modes based on your environment, delivering the accuracy benefits of multi-band while preserving battery life.[1]

How SatIQ Works

SatIQ continuously monitors signal quality and environmental conditions. In open sky conditions where single-frequency GPS provides sufficient accuracy, SatIQ uses the lower-power mode. When entering challenging environments like urban canyons, dense forests, or mountain terrain, SatIQ automatically activates multi-band GNSS. The switching happens seamlessly in the background without user intervention.

Battery Savings with SatIQ

According to Garmin's testing, multi-band GNSS is typically needed only about 15% of the time during an activity. With SatIQ, you get near-100% accuracy throughout your activity while battery drain from multi-band only occurs during that 15% of time when it's needed. Overall battery life approaches single-frequency modes while maintaining multi-band accuracy.[1]

Watches with SatIQ

Compare all watches with SatIQ →

Satellite Modes on Garmin Watches

Garmin watches with GNSS support typically offer several satellite mode options:

Mode Description Battery Impact Best For
GPS Only Uses only GPS satellites Lowest Open sky, maximum battery life needed
GPS + GLONASS Uses GPS and GLONASS constellations Low General use, slight accuracy improvement
GPS + Galileo Uses GPS and Galileo constellations Low General use in regions with good Galileo coverage
All Systems Uses all available GNSS constellations (GPS, GLONASS, Galileo, etc.) Medium Challenging environments, best single-band accuracy
All Systems + Multi-Band All GNSS constellations with dual-frequency Highest Maximum accuracy in difficult terrain
Auto Select (SatIQ) Automatically switches between modes Adaptive Best balance of accuracy and battery life

Choosing the Right Satellite Mode

For most users, the choice of satellite mode depends on the activity and environment. GPS Only mode is sufficient for running on open roads or tracks, cycling on clear paths, activities where battery life is critical, and ultra-distance events in open terrain.

All Systems mode works well for trail running in forests, urban running between buildings, hiking in variable terrain, and when you want consistent accuracy without heavy battery drain.

Multi-Band mode is ideal for technical trail running with heavy tree cover, mountain activities with cliffs and valleys, urban navigation between skyscrapers, and activities where track accuracy is critical such as mapping.

SatIQ or Auto Select mode is recommended for activities crossing multiple terrain types, when you don't want to think about settings, long activities where battery and accuracy both matter, and traveling to unfamiliar terrain.

Satellite Constellations

The following satellite constellations are used by Garmin watches to provide positioning data:

GPS (United States)

The Global Positioning System (GPS) is the oldest and most established GNSS, operated by the United States Space Force. Launched in 1978 and fully operational since 1995, GPS consists of at least 24 satellites orbiting Earth and provides global coverage.[3]

Attribute Details
Operator United States Space Force
Satellites 31 operational (minimum 24 required)
Orbital Altitude ~20,200 km
Coverage Global
Civilian Accuracy ~3-5 meters (single frequency)
First Launch 1978
Full Operational Capability 1995

GPS is supported by virtually all Garmin watches with satellite navigation capabilities.

GLONASS (Russia)

GLONASS (Global Navigation Satellite System, Russian: ГЛОНАСС) is Russia's global satellite navigation system. Originally developed by the Soviet Union starting in 1976, it became fully operational in 1995, was degraded in the early 2000s, and was restored to full global coverage in 2011.[4]

Attribute Details
Operator Russian Aerospace Forces (Roscosmos)
Satellites 24+ operational
Orbital Altitude ~19,100 km
Coverage Global
Civilian Accuracy ~5-10 meters (single frequency)
First Launch 1982
Full Operational Capability 1995 (restored 2011)

GLONASS satellites have different orbital planes than GPS, which can improve accuracy in high-latitude regions and urban canyons where GPS signals may be blocked.

Galileo (European Union)

Galileo is the European Union's global satellite navigation system. Unlike GPS and GLONASS, which were originally developed for military purposes, Galileo was designed from the start as a civilian system. It began providing initial services in 2016 and reached full operational capability in 2024.[5]

Attribute Details
Operator European Union (EU Agency for the Space Programme)
Satellites 30 planned (24+ operational)
Orbital Altitude ~23,222 km
Coverage Global
Civilian Accuracy ~1 meter (with dual frequency)
First Launch 2011
Initial Services 2016

Galileo offers higher accuracy than GPS or GLONASS, particularly when using dual-frequency signals. Most modern Garmin watches support Galileo.

BeiDou (China)

BeiDou (北斗, meaning "Big Dipper") is China's global satellite navigation system. The third generation (BeiDou-3) achieved global coverage in 2020 and offers enhanced accuracy, particularly in the Asia-Pacific region.[6]

Attribute Details
Operator China National Space Administration
Satellites 35+ operational (BeiDou-3)
Orbital Altitude ~21,150 km (MEO) + GEO/IGSO
Coverage Global (enhanced Asia-Pacific)
Civilian Accuracy ~3.6 meters (global), ~2.6 meters (Asia-Pacific)
First Launch 2000 (BeiDou-1)
Global Coverage 2020 (BeiDou-3)

BeiDou support varies by Garmin watch model and region. Some watches sold in certain markets include BeiDou support.

QZSS (Japan)

QZSS (Quasi-Zenith Satellite System) is a regional satellite navigation system operated by Japan. It is designed to enhance GPS accuracy in Japan and the Asia-Oceania region, particularly in urban canyons and mountainous areas where GPS signals may be obstructed.

Attribute Details
Operator Japan Aerospace Exploration Agency (JAXA)
Satellites 8 operational (7/24 planned: NVS/GINS)
Orbital Type Quasi-zenith orbit (high elevation over Japan)
Coverage Regional (Japan and Asia-Oceania)
Purpose GPS augmentation
Operational 2018

QZSS is supported by some Garmin watches, primarily those sold in the Asia-Pacific region.

IRNSS (India)

IRNSS (Indian Regional Navigation Satellite System), with an operational name of NavIC (acronym for Navigation with Indian Constellation), is a regional satellite navigation system operated by the Indian Space Research Organisation, the national space agency of India. It is designed to provide regional coverage of India and a region extending 1,500 km around it.

Attribute Details
Operator Indian Space Research Organisation (IRSO)
Satellites 5 operational (7 planned)
Orbital Altitude 35,786 km
Coverage Regional (India)
Civilian Accuracy 3 meters (public), 2 meters (encrypted)
First Launch 2013

IRNSS is supported by some Garmin watches, primarily those sold in the Indian region.

See Also

References

  1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Garmin Blog: Garmin Engineer Talks SatIQ: Longer Battery Life, Same Precise Tracking
  2. ↑ Garmin Support: GNSS Systems
  3. ↑ GPS.gov: Official U.S. Government Information
  4. ↑ ESA Navipedia: GLONASS General Introduction
  5. ↑ ESA: What is Galileo?
  6. ↑ BeiDou Navigation Satellite System Official Website
Retrieved from "https://wiki.garminrumors.com/index.php?title=Global_Navigation_Satellite_Systems&oldid=2748#QZSS_(Japan)"
Garmin Wiki
A project by GarminRumors.com