The opposite day we had been scrolling by r/meshtastic and somebody asks: “Why does my system present 10+ satellites in view whereas my buddy’s barely sees 8?” Good query. Actually good query, truly. And it is about to take us down a rabbit gap that entails atomic clocks, Chilly Battle competitors, European independence, and why your Meshtastic node cares about all of this.
Most individuals name it “GPS” as a result of that is what we grew up with. However here is the factor: GPS is only one piece of a a lot larger puzzle known as GNSS. It is like how individuals say “Google it” after they imply “search the online”, GPS grew to become the catch-all time period for satellite tv for pc navigation, regardless that there at the moment are six totally different techniques orbiting Earth doing the very same factor.
Buckle up. We’re about to elucidate GNSS (and why it isn’t simply “GPS”), how your location will get calculated to inside meters, how, and why time synchronization is so necessary, and whether or not extra satellite tv for pc techniques truly means higher efficiency on your off-grid adventures.
Let’s begin with the fundamentals. You understand whenever you’re searching for a Meshtastic system and the seller specs say one thing like:
“GPS/GLONASS/Galileo/BeiDou/NavIC/QZSS assist”
That is not advertising fluff. These are six totally different satellite tv for pc constellation techniques orbiting Earth proper now, and if you wish to use your system as a severe tracker or care about quick GPS locks and accuracy, it is best to completely search for this within the specs. Plenty of distributors do not even point out it, so you must dig into the GPS chip mannequin to determine what you are truly getting.
GNSS stands for World Navigation Satellite tv for pc System. It is the umbrella time period for any satellite-based navigation system. GPS is only one taste of GNSS, particularly, the one run by the US. However since GPS was first and dominated for many years, everybody simply calls it “GPS” even after they’re utilizing 5 totally different techniques without delay.
Consider it this manner:
- GNSS = “search engine”
- GPS = “Google”
- GLONASS = “Yandex”
- Galileo = “DuckDuckGo”
- BeiDou = “Baidu”
All of them do the identical job (assist you determine the place you might be), however they’re run by totally different nations, use totally different satellites, and have barely totally different strengths.
The Massive Gamers: A Fast Rundown
This is who’s who within the satellite tv for pc navigation sport:
| System | Nation/Area | Satellites | Standing | Protection |
|---|---|---|---|---|
| GPS | United States | 31 lively | Absolutely operational since 1995 | World |
| GLONASS | Russia | 24 lively | Absolutely operational since 1995 | World |
| Galileo | European Union | 30 lively | Absolutely operational since 2016 | World |
| BeiDou | China | 35+ lively | Absolutely operational since 2020 | World |
| NavIC | India | 7 lively | Regional (2016) | India + 1,500km radius |
| QZSS | Japan | 7 lively | Regional augmentation | Asia-Pacific |
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Enjoyable truth: Proper now, there are about 120-130 navigation satellites orbiting Earth at any given second. That is wild. And your Meshtastic node? It might probably see an honest chunk of them.
Wish to see which satellites are above you proper now? Try gnssplanning.com, it is a killer instrument that exhibits you precisely which satellites from which techniques are seen at your location. Simply plug in your coordinates and time, and you’ll see GPS, GLONASS, Galileo, BeiDou, and QZSS satellites in real-time. Tremendous helpful for planning out of doors journeys or troubleshooting why your node is not getting repair.
Why Do Nations Construct Their Personal Satellite tv for pc Methods? (Spoiler: Politics)
You is perhaps questioning: “If GPS works high-quality, why did Europe, Russia, and China spend billions constructing their very own techniques?”
Nice query. The reply is mainly: “We do not belief the US to not flip GPS off throughout a warfare.”
No, actually. That is it.
The GPS Story
GPS was initially a army venture. The U.S. Division of Protection launched it within the Nineteen Seventies-80s for missile steering and troop coordination. For a very long time, civilian GPS was intentionally degraded, which means the army had entry to correct positioning (~1 meter), whereas civilian gadgets obtained a intentionally fuzzy sign (~100 meters). This was known as “Selective Availability” and it lasted till 2000.
Even after the U.S. turned off Selective Availability, different nations obtained nervous. What if, throughout a battle, the U.S. determined to close off GPS completely? Or degrade it once more? Immediately your whole financial system, delivery, aviation, agriculture, grinds to a halt.
So Russia stored GLONASS (initially constructed throughout the Soviet period). Europe constructed Galileo. China constructed BeiDou. India constructed NavIC. Japan enhanced GPS with QZSS.
The outcome? We now have redundancy. If one system goes down (or will get sabotaged), others can decide up the slack. And for Meshtastic customers, this implies extra satellites = higher place fixes.
How Does Your Meshtastic Node Really Know The place It Is?
Alright, time for the technical magic. How does a piece of silicon the scale of a fingernail work out that you just’re standing at 35.6762°N, 139.6503°E (hiya from Tokyo)?
The reply: trilateration + atomic clocks + actually quick math.
Step 1: Satellites Scream Their Place at You
Each GNSS satellite tv for pc always broadcasts two items of knowledge:
- “This is precisely the place I’m proper now” (orbital parameters)
- “This is the precise time, in line with my onboard atomic clock” (timestamp)
These satellites have crazy-accurate atomic clocks that drift by solely 1 nanosecond per day. (A daily quartz watch drifts by about 15 seconds per day, for comparability.)
Step 2: Your Receiver Measures the Time Delay
When your Meshtastic node’s GPS chip receives a sign from a satellite tv for pc, it does this calculation:
Distance = (Sign Journey Time) × (Pace of Gentle)
Radio waves journey on the pace of sunshine (~300,000 km/s). So if a sign takes 0.07 seconds to succeed in you from a satellite tv for pc, you understand you are about 21,000 kilometers away from that satellite tv for pc.
However here is the issue: understanding you are 21,000 km from one satellite tv for pc does not inform you a lot. You would be wherever on a sphere with a 21,000 km radius round that satellite tv for pc.
So that you want extra satellites.
Step 3: Trilateration (Not Triangulation!)
- With 1 satellite tv for pc: You are someplace on a sphere round it.
- With 2 satellites: You are someplace on the circle the place two spheres intersect.
- With 3 satellites: You are at one in every of two factors the place three spheres intersect.
- With 4 satellites: You get a exact 3D place (latitude, longitude, altitude).
Why 4 satellites minimal? As a result of your Meshtastic node does not hold time, some have RTC however that’s matter for an additional day. The 4th satellite tv for pc is used to right for the clock error in your receiver.
How Radio Frequencies Actually Work: From Electrons to Your WiFi
Discover how radio frequency (RF) works—from electrons to WiFi. Learn how changing currents create electromagnetic waves, how crystals like TCXO and VCO power modern communication, and how your devices turn digital bits into wi-fi alerts touring on the pace of sunshine.
The Math (For Nerds Solely)
If you wish to geek out, here is the precise equation your GPS chip is fixing:
√[(X - X₁)² + (Y - Y₁)² + (Z - Z₁)²] = c(t - t₁)
The place:
(X, Y, Z)= Your unknown place(X₁, Y₁, Z₁)= Satellite tv for pc placec= Pace of sunshinet= Your receiver’s timet₁= Satellite tv for pc’s transmission time
Your GPS chip solves this equation concurrently for 4+ satellites, each second, in real-time. Fairly wild, proper?
How Meshtastic Will get Time From Satellites (And Why It Issues)
This is one thing most individuals do not understand: Your Meshtastic community wants correct time simply as a lot because it wants correct place.
Why Time Sync Issues for Mesh Networks
Meshtastic makes use of LoRa, which is a time-slotted protocol. Nodes must know:
- When to transmit
- When to hear
- Learn how to keep away from collisions with different nodes
- Learn how to timestamp messages for routing
If nodes have wildly totally different clocks, the mesh falls aside. Messages collide. Routing will get confused. Chaos.
How GNSS Gives Time
Each GNSS satellite tv for pc has an onboard atomic clock synchronized to an extremely exact timescale:
- GPS Time (maintained by the U.S. Naval Observatory)
- GLONASS Time (maintained by Russia)
- Galileo System Time (maintained by ESA)
- BeiDou Time (maintained by China)
These timescales are synchronized to inside nanoseconds of one another.
When your Meshtastic node locks onto satellites, it isn’t simply getting place—it is getting ultra-precise time. This will get distributed throughout the mesh community, retaining all nodes in sync.
Sensible instance: As an instance you are mountain climbing with 10 mates, all with Meshtastic nodes. Solely one particular person wants GPS. That node can act because the “time authority” for your entire mesh, broadcasting time updates to everybody else. The opposite nodes can flip off their GPS to save lots of battery.
Breaking Down the Methods: GPS vs GLONASS vs Galileo vs BeiDou
Now let’s speak specifics. What makes every GNSS constellation totally different? And does it matter on your Meshtastic setup?
GPS (United States)
Launch: 1978 (absolutely operational 1995)
Satellites: 31 lively (24 minimal required)
Orbit: Medium Earth Orbit (MEO), ~20,180 km altitude
Accuracy: ~5-10 meters (civilian), ~1-2 meters (army)
Frequency Bands: L1 (1575.42 MHz), L2, L5
Strengths:
- Most mature system with finest international protection
- Widest system assist (each GPS chip helps it)
- Intensive floor management community
- Free, no utilization charges
Weaknesses:
- U.S. controls it—may very well be degraded or shut off
- Older satellites could have much less correct clocks
- Not as many satellites as BeiDou
For Meshtastic Customers:
- In case your system solely has GPS, you are still high-quality. It is the gold commonplace.
- Chilly begin can take 30+ seconds to accumulate repair
GLONASS (Russia)
Launch: 1982 (absolutely operational 1995)
Satellites: 24 lively
Orbit: MEO, ~19,130 km altitude
Accuracy: ~5-10 meters
Frequency Bands: L1 (1602 MHz), L2 (1246 MHz)
Strengths:
- Higher protection at excessive latitudes (like Alaska, Scandinavia, Russia)
- Makes use of FDMA as a substitute of CDMA (totally different sign construction)
- Unbiased from U.S. management
Weaknesses:
- Barely much less correct than GPS/Galileo
- Satellites put on out quicker (shorter lifespan)
- Makes use of extra energy in receivers
For Meshtastic Customers:
- GPS + GLONASS combo considerably improves repair pace
- Nice should you’re mountain climbing in northern latitudes
- Drains battery ~10-15% quicker than GPS alone
Galileo (European Union)
Launch: 2011 (absolutely operational 2016)
Satellites: 30 lively
Orbit: MEO, ~23,222 km altitude (highest orbit of all)
Accuracy: ~1 meter (free service), ~0.01 meters (industrial)
Frequency Bands: E1 (1575.42 MHz), E5a, E5b, E6
Strengths:
- Most correct civilian system (higher than GPS!)
- Higher sign penetration (helpful in forests/city areas)
- Constructed for civilian use from the bottom up
- Search and Rescue (SAR) service built-in
Weaknesses:
- Latest system, nonetheless constructing out
- Not as broadly supported in older chips
- EU management (much less related for many customers)
For Meshtastic Customers:
- In case your system has Galileo assist, use it
- Noticeably quicker time-to-first-fix (TTFF)
- Finest for city/forest environments
BeiDou (China)
Launch: 2000 (BeiDou-1), absolutely international 2020 (BeiDou-3)
Satellites: 35+ lively (most of any system!)
Orbit: Blended—MEO, IGSO, and GEO satellites
Accuracy: ~5-10 meters (free), ~0.1 meters (premium)
Frequency Bands: B1 (1561.098 MHz), B2, B3
Strengths:
- Most satellites in orbit (higher availability)
- Glorious protection in Asia-Pacific
- Two-way messaging function (distinctive to BeiDou!)
- GEO satellites present 24/7 protection in some areas
Weaknesses:
- Blended orbital varieties can complicate processing
- Not as correct globally as Galileo
- China controls it (geopolitical issues)
For Meshtastic Customers:
- If you happen to’re in Asia, search for BeiDou
- The 2-way messaging function is not accessible to client gadgets (but)
- Nice for enhancing satellite tv for pc depend in city canyons
NavIC & QZSS (Regional Methods)
NavIC (India):
- 7 satellites masking India + 1,500 km radius
- Designed for regional sovereignty
- Not tremendous helpful except you are in India
QZSS (Japan):
- 7 satellites augmenting GPS in Asia-Pacific
- Improves accuracy in Japan, Australia, Southeast Asia
- Works with GPS, not standalone
For Meshtastic Customers:
- These are “good to have” however not game-changers
- In case your chip helps them, it’s even higher
So, Why Do Some Meshtastic Gadgets See Extra Satellites?
Again to the unique query: Why do some Meshtastic gadgets present 10+ satellites whereas others may solely see 8?
Purpose 1: Completely different GPS Chips
That is the large one. Some gadgets use low cost GPS modules that solely assist GPS + GLONASS. Others use fashionable multi-GNSS chips that may monitor all the things:
- Finances chips (like older NEO-6M modules): GPS + GLONASS solely
- Mid-range chips (like ATGM336H): GPS + BeiDou
- Trendy chips (like UBlox MAX-M10S, MediaTek AG3335): GPS + GLONASS + Galileo + BeiDou + QZSS
Extra supported techniques = extra satellites in view.
Whenever you’re searching for a Meshtastic system, the GPS chip mannequin issues manner greater than most individuals notice. A tool with a MediaTek AG3335 or UBlox M10 will completely destroy a NEO-6M by way of satellite tv for pc depend and accuracy.
Purpose 2: Antenna High quality
Excessive-end gadgets typically include ceramic patch antennas designed particularly for GNSS reception. Finances builds or DIY setups may use low cost exterior antennas with poor acquire, or worse, no antenna optimization in any respect.
Higher antenna = higher sign reception = extra satellites detected.
If you happen to’re severe about GPS efficiency, antenna high quality issues virtually as a lot because the chip itself. An excellent chip with a horrible antenna will nonetheless battle.
Purpose 3: Firmware Configuration
Some GPS modules should be explicitly configured to allow multi-GNSS assist. In case your firmware solely allows GPS, you will not see GLONASS/Galileo satellites even when the chip helps them.
Purpose 4: Geographic Location
Relying on the place you might be on Earth, you will see totally different satellites:
- Equatorial areas: See extra MEO satellites from all techniques
- Northern latitudes: GLONASS protection improves
- Asia-Pacific: BeiDou dominates, QZSS helps
- City canyons: Want extra satellites from extra techniques
The Efficiency Query: Is Extra All the time Higher?
You’d assume having 30 satellites in view is best than 8. And customarily, it’s. However there are diminishing returns.
Satellite tv for pc Visibility vs. Accuracy
| Satellites in View | Typical Accuracy |
|---|---|
| 4 satellites | ~15-30 meters |
| 6-8 satellites | ~5-10 meters |
| 10-15 satellites | ~3-5 meters |
| 20+ satellites | ~2-4 meters |
Discover how accuracy enhancements drop off after ~10 satellites? That is due to two elements:
- Geometric Dilution of Precision (GDOP): Having satellites evenly distributed within the sky issues greater than uncooked depend. 8 well-spaced satellites beat 20 clustered satellites.
- Processing Overhead: Your GPS chip can solely monitor a sure variety of satellites concurrently. Extra techniques = extra processing = extra energy draw.
Energy Consumption Commerce-offs
Enabling extra GNSS techniques makes use of extra battery:
- GPS solely: Baseline energy consumption
- GPS + GLONASS: +10-15% energy
- GPS + GLONASS + Galileo: +15-20% energy
- GPS + GLONASS + Galileo + BeiDou: +20-30% energy
For a battery-powered Meshtastic node on a multi-day hike, this issues.
Advice:
- For mounted/photo voltaic nodes: Allow all the things. You’ve gotten energy to spare.
- For battery-powered handhelds: Deal with GPS + Galileo (finest accuracy-per-watt).
- For ultra-low-power trackers: GPS is sufficient, with sensible broadcast enabled.
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Enjoyable Reality: You may assume it’s a rip-off when distributors promote a photo voltaic node with a GPS chip, in spite of everything, it’s bolted to a roof and by no means strikes! However right here’s the key: GPS chips do not simply inform you the place you might be; they obtain time from atomic clocks in house. Since photo voltaic nodes often have the very best view of the sky, that “pointless” GPS chip truly grabs good time and shares it with the remainder of the mesh. It turns into the Timekeeper for each different node within the valley that is perhaps offline or deep within the woods.
Conclusion: Extra Satellites = Extra Higher (Often)
So, again to the unique query: Why do some Meshtastic gadgets present extra satellites?
As a result of they’ve higher GPS chips with multi-GNSS assist, higher antenna design, and fashionable firmware that allows all out there techniques.
Does that make them higher?
For many use instances, sure. Extra satellites means: quicker preliminary repair, higher accuracy, extra resilience in difficult environments, and higher mesh time sync.
But it surely comes at a value: larger energy consumption, costlier {hardware}, and overkill for some functions
The candy spot for many Meshtastic customers: GPS + Galileo (finest stability), sensible broadcast enabled, exterior antenna for mounted nodes, and search for fashionable GPS chips when procuring (UBlox M10 sequence, MediaTek AG3335, and so on.)
And keep in mind: the entire level of Meshtastic is constructing resilient, off-grid communication networks. Having dependable positioning is a part of that puzzle. Whether or not you are coordinating a mountain climbing group, monitoring property, or constructing a disaster-ready mesh community, understanding GNSS (sorry, “GPS”) helps you make higher {hardware} and configuration selections.
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Professional tip: Earlier than shopping for a Meshtastic system, verify the GPS chip specs. A tool with a NEO-6M is perhaps $10 cheaper, however a tool with an M10 chip offers you manner higher efficiency. Generally that further price is completely value it.
