[time-nuts] Re: looking for multi-constellation GNSS nav receiver with bluetooth or WiFi interface

[Greg Troxel]

Brian Lloyd via time-nuts <time-nuts at lists.febo.com> writes:

> This is somewhat off-topic for time nuts but probably on-topic for the
> GNSS aficionados that lurk about here.

The things I will mention have PPS pins so they count as on topic :-)

> I am working on a book about long-distance flying and, knowing the
> potential fragility of single-constellation GNSS, especially GPS, I
> have been trying to find a multi-constellation sensor that goes beyond
> GPS + GLONAS. Does anyone know of a packaged nav sensor that includes
> GPS, GLONAS, BeiDou, and Galileo? Yes, I have followed all the
> discussion of the newer multi-constellation GNSS modules that are now
> out there but I haven't been successful in finding a packaged nav
> sensor with a WiFi or Bluetooth interface that can integrate with
> various nav packages available for aviation, e.g. ForeFlight.

I'm not sure why you think single-constellation GPS is worse than
single-constellation for the other 3.

I know of two product families.  Very roughly they are an F9P with an
ESP32 that has wifi and/or bluetooth.

iOS is difficult as Bluetooth SPP requires paying some kind of special
Apple licensing fees, as I understand it.  The things I am pointing to
don't do that.  SPP works fine on computers and Android.

Besides data plumbing, it can be nice to have a battery which can hold
ephemeris and RTC.

You may not be thinking about RTK, but the following have on-module RTK.

* Ardusimple

This was available first.  It can come no case, no battery, and thus
smaller size/weight.  Arduino form factor with native serial and
serial-over-USB.   It has a daughtercard socket and a wifi interface is
one option.   I believe bluetooth is available too.

One big downside is a lack of software maintenance/development on the
WiFi daughterboard.  The code is open soure, but I just don't see much
happening.

Besides F9P, which is L1/L2 and 4 constellations, there is a version
with a Septentrio part which adds additional bands.

https://www.ardusimple.com/simplertk2b-receivers/
https://www.ardusimple.com/simplertk3b-receivers/

* Sparkfun

This is more recent, and is more of a case/battery/display/UI with a
receiver.  There is an ESP32 builtin (vs daughtercard) and the firmware
will do WiFi (to fetch RTCM3, and maybe to provide nav solutions) and
Bluetooth SPP, and I have seen traffic about BLE.  The ESP32 software is
open source and it is under very active development; I've asked for
features and seen them happen.

https://www.sparkfun.com/products/18442

https://www.sparkfun.com/products/18590 (F9R: IMU fusion, no RTK base)

https://www.sparkfun.com/products/19984 (integrated antenna)



Overall I would lean to the sparkfun because of the software situation,
unless you need the lighter weight and smaller size.   If you're
using an antenna like one of

  https://www.ardusimple.com/product/calibrated-survey-gnss-multiband-antenna-ip67/
  https://www.sparkfun.com/products/17751

and a prism pole, the size/weight difference doesn't matter, and the
battery, status display, and better software tips the advantage to
SparkFun.