Required LTE Beacon Visibility

#1

Hello,

Just got our LTE beacons and am having a bit of a play around and just wanted to check to see if the performance i was getting was out of the ordinary at all.

I made a basic micro-app program to provide the position, ideally, every minute (naturally wouldn’t use this sort of frequency in the real world with the rate this would chew up the battery).

location.startUpdates((position) => {
print(lattitude=${position.lat} longitude=${position.long});
cloud.enqueue(‘position’, position);
sync.now();
},{minInterval: 60 /* s /, minDistance: 0 / m /, timeout: 0 / s */});

After work i placed the beacon in my leather satchel and took it home with me on the train. I’ve highlighted the trip in green in the provided image.
It seems as if I didn’t get a single response for the entirety of the trip which lasted a bit over 40 mins. It was only while i was waiting at the station and had arrived home that it provided a location.

You can see the large gap in the data below

Does it struggle to find a satellite while in a vehicle or is there a problem with my program?

#2

I just plotted the the results using different a different program i got much better resolution, now it shows me walking from the train station. The original program doesn’t seem to like lat and long values down to 12 decimal places :stuck_out_tongue:
So it seems to be able to get the position while it’s sitting in a satchel, but there’s still the issue of getting the position while in a train

#3

Sounds like a problem with line-of-sight to satellites. On your next trip, you could try putting it near a window to confirm.

For what it’s worth, when I was still a student regularly taking a train to my hometown, my iPhone also struggled with GPS while riding, and usually reverted to cellular-tower-based location. A big box of metal isn’t too friendly for electromagnetic waves at these frequencies.

#4

So you’re saying these advertisements are slightly misleading then?

?

#5

I wouldn’t know about our marketing materials :man_shrugging: :wink:

At the end of the day, it’s all very dependent on the environment. Bluetooth signal should be able to penetrate metal, albeit with a big hit to the signal strength (= the energy of the electromagnetic wave). Cellular too. But of course, you can always build a metal cage “strong” enough to isolate the outside electromagnetic radiation completely—we use such boxes for our shipping & QA procedures, and they’re definitely very effective.

GPS is what I’m the least familiar with, but generally speaking, we use more-or-less the same GPS/GNSS that’s in your smartphone (or car navigation, if that’s still a thing :P), maybe with a bit different antenna.

Worst comes to worst, we can always add fall-back to cellular-tower-level resolution for outdoor asset tracking, just like iPhones and Androids do.

#6

(Re: this being environment-dependent: I remember one of our engineers testing one of the early LTE Beacon prototypes by putting it in a backpack and riding a streetcar home, and then showing it to us on a Google Map during our internal demo-day—and it did work in that environment.)