top | item 37706145

(no title)

mukara | 2 years ago

Signals from Galileo, GLONASS, and BeiDou (and other semi-regional navigation satellite constellations) can be received in the US. Any decent GNSS receiver you can purchase in the US will be able to receive all 4 major global constellations. I know this cause I work with them everyday.

Even the typical “premium” cellphone will receive all 4. (I know some Android manufacturers disable the used of BeiDou, but they can still receive it.) The iPhone 15 Pro’s tech specs mention “Precision dual-frequency GPS (GPS, GLONASS, Galileo, QZSS, BeiDou, and NavIC)”.

discuss

order

ShakataGaNai|2 years ago

Yea. Even if not officially approved by the FCC etc, the signals are still being broadcast. So there may be interference, but the signals are there and often receivable.

The problem is really just that while premiums consumer devices support basically all GNSS providers, that's not true of a lot of devices. There is a lot of cheap/old/specialized systems out there that are still GPS only.

In the case of a GPS shutdown, I'm not worried about my iPhone 15. However, what is currently in place and certified for flight in a 30 year old 757? Have they gotten around to generic GNSS support or is it just GPS? I honestly don't know and would rather we didn't have to find out the hard way.

wkat4242|2 years ago

The "interference" is actually how GNSS systems work and it makes things better.

joecool1029|2 years ago

> Any decent GNSS receiver you can purchase in the US will be able to receive all 4 major global constellations. I know this cause I work with them everyday.

All common handset devices used in CONUS (every iphone, android phone, etc) will ignore BeiDou signals. Would love if someone hacked the GNSS firmware to make it usable, but haven't seen it happen yet. If you travel outside the CONUS geofence these signals will show on the device, but FCC has some mandate requesting a block, so it's blocked.

mukara|2 years ago

>All common handset devices used in CONUS (every iphone, android phone, etc) will ignore BeiDou signals.

This is correct for smartphones and the likes (all handsets??), though not entirely correct for all GNSS receivers. For example, I regularly use receivers with uBlox F9P chipsets with BeiDou enabled from factory [0].

>Would love if someone hacked the GNSS firmware to make it usable, but haven't seen it happen yet.

If we ask the Broadcom or Qualcomm engineers nicely, they might tell us how to unblock them for their smartphone chipsets in the US. I might’ve seen it before :)

[0] https://www.digikey.com/en/products/detail/ardusimple/AS-RTK...

hef19898|2 years ago

Plus, some receivers can work with signals coming from different cobstellations, e.g. one GPs, one GLoNAS and one Galileo, in order to provide a proper position.

smachiz|2 years ago

I think technically they should only receive for Galileo in the US - unless any of the others have also received exceptions from the FCC.

While in other countries, presumably your phone turns on the additional sources.

mukara|2 years ago

Not sure about “technically” or what the legal situation is. In practice, I know consumer smartphones in the US use a combination of all 4 constellations for positioning. If you have Android, you can easily verify this using various apps. If you're on the west coast (California Bay Area, at least), you can even receive unreliable signals from one or two Japanese QZSS satellites, which are supposed to be regional over the Asia-Oceania region. You can even see a few SBAS satellites (mainly used in aviation.)

deaddodo|2 years ago

Have an American model Android phone. Used it in Mexico, the US and Ireland. In all places it used GLONASS, GPS and Galileo equally (assuming equal satellite visibility, of course).