Garmin Accuracy

Refresh rate is unambiguous, but to the casual observer is obscured. Watching the screen of my DS-51 it seems sorta like 5 seconds (.2 Hz.) but what we get to see is the video refresh rate. One hopes that the GPS refresh rate is faster.

I was poking around on-line this weekend and ran across a similar thread about accuracy on GPSrChive.

https://gpsrchive.com/Discussion/viewtopic.php?f=165&t=2476

There was discussion about the chipset supporting multi-GNSS and multi-band. This is what Garmin states about that:

https://support.garmin.com/en-US/?faq=9NWiPDU4gM0JWMfdWFol7A

Here is the list of Compatible Devices With Multi-Band Technology:

Approach S70-47mm

D2 Mach 1

epix (Gen 2) Sapphire

epix Pro (Gen 2) - Standard Edition 42mm and all other models in the epix Pro (Gen 2) series

fēnix 7 Sapphire Solar and all other models in the fēnix 7 Sapphire Solar series

fēnix 7 Pro Solar and all other models in the fēnix 7 Pro Solar series

fēnix 7 Pro Sapphire Solar and all other models in the fēnix 7 Pro Sapphire Solar series

Edge 540/Edge 540 Solar

Edge 840Edge 840 Solar

Edge 1040/Edge 1040 Solar

Enduro 2

Forerunner 255/Forerunner 255S/Forerunner 255 Music/Forerunner 255S Music watches

Forerunner 265/Forerunner 265S watches

Forerunner 955/Forerunner 955 Solar watches

Forerunner 965 watch

Foretrex 801/Foretrex 901 Ballistic Edition

GPSMAP 65/GPSMAP 65s

GPSMAP 66sr

GPSMAP 67/GPSMAP 67i

Instinct 2X Solar/Instinct 2X Solar-Tactical Edition Watches

tactix 7-Standard Edition and all other models in the tactix 7 series

These are Garmin watches, handhelds (GPSMAP Series), cycling computers (Edge) and wrist-mounted GPS navigators (Foretrex).

I don't see any Garmin Automotive navigators with it, yet.

https://www.garmin.com/en-US/blog/outdoor/why-multi-band-qa-...

Refresh rate is relevant for capturing changes. The simplest change is linear velocity. The faster your application, the more you want a higher refresh rate. In many cases keeping up with changes in direction is more challenging. A highly dynamic platform wants a high refresh rate.

It has zip to do with getting better accuracy if the receiver is just sitting still trying to get an accurate location for the corner of your house lot.

Some additional Garmins devices are now available with multi-band technology. The Garmin Edge 1050 was announced a couple of months ago. There may be others, too, but that just happens to be one that I noticed.

https://www.garmin.com/en-US/newsroom/press-release/sports-f...

I'd like to understand "multi-band". I searched that page for "band" to no avail. Heck,,, the letters "gps" couldn't be found. I'm hoping that it isn't in the video since I struggle to learn anything from videos and no longer try.

https://support.garmin.com/en-US/?faq=9NWiPDU4gM0JWMfdWFol7A

Dual-frequency or "Multi-Band" systems use multiple frequency bands and allow for more consistent tracklogs and improved positioning when using the device in challenging environments. This means the receiver tracks more than one radio signal from each satellite on different frequencies, which can reduce errors caused by environmental interference.

The illustrations below show how dual-frequency systems are better able to filter out inaccurate signals reflecting off of buildings, trees, or mountains.

What Advantages Do Multi-Band Devices Have Over Other Models?
More consistent tracklogs and improved positioning when using the device in challenging environments (e.g. around tall buildings in urban canyons as well as tree cover)

Can achieve accuracy within about +/- 2 meters or 6 feet under ideal conditions versus the +/- 3 meters or 10 feet accuracy of other models

Detect (and reject) reflected satellite signals better than a single frequency receiver which improves accuracy

Better equipped to account for and correct errors that can be introduced by atmospheric effects (e.g. ionosphere errors)

Which Frequency Bands Do Multi-Band Devices Track?
The following table shows what frequency bands can be tracked depending on the satellite settings that have been enabled and device location:

Multi-GNSS Frequency Bands
Satellite System Built By GPS Only Multi-GNSS (All Systems) Multi-GNSS (All) + Multi-Band
GPS United States L1 L1 L1 & L5
GLONASS1 Russia
L1 L1
GALILEO European Space Agency
E1 E1 & E5a
QZSS Japan
L1 L1 & L5
IRNSS (NavIC) India
L1 L1 & L5
BeiDou2 China
B1 B1
Some satellite systems are not going to be available in some areas. For example, the IRNSS system is not available on the west coast in Salem, OR. Check the satellite provider's website for coverage information.

1 GLONASS is not available on devices with inReach® satellite communication features.

2 BeiDou is not available on the GPSMAP 65 series or GPSMAP 66sr.

Does anybody here get accuracy of better than 10 feet?

No

Drive Smart 61 (GPS & Galileo) 10ft
Drive Smart 55 (GPS & Galileo) 10ft
Nuvi 50 (GPS) 37ft (it took several minutes to get down to 37ft)
Nuvi 58 (GPS) 28ft

Thanks JIM1348. It turns out that my handheld gps (GPS + GLONASS) and my auto gps (GPS + GALILEO) all run it 1 to 2 GHz. Win some,,, lose some!

I have seen the EPE as low as 3' on one of my handhelds while boating on open water. Keep in mind, that number is the estimated position error. The actual error could be more or less depending on the number of satellites in view.

Is that unit WAAS-enabled?