Helium mobile coverage points and overlapping coverage explained

Helium mobile coverage points and overlapping coverage explained

The old rewards way

Before Dec 4th 2023. You used to be rewarded for just having your radios online, and passing the speedtest. Every radio of the same type would pretty much earn around the same amount of mobile tokens. For example a 430 near the end of November was earning around 12,000 mobile tokens. These days are over now and it all depends on how many coverage points you have. In simple terms, the more you cover the more you are rewarded.

The new/current rewards way

We need to understand the basics of the hex system first. When you install a radio, it will provide coverage. This coverage is made out of hexes on a map. Each hex represents a different level of signal per hex.

To give a better understanding of the hex size. It’s about 63 feet in width.

Outdoor units

This is the current structure for outdoor radios such as the 436h, outdoor wifi and 430h.

High signal: 16 coverage points

Medium signal: 8 coverage points

Low signal: 4 coverage points

In the image above we have colored the respective hexes with their signal levels. The white hex is where the radio is installed. It’s facing south-east around 150 degrees. Because it's facing like this you can see the couple hexes behind it, they are low signal because that's the rear of the radio where only weak signal escapes a bit. Looking towards the front you can see 2 hexes that are red high signal, followed by 4 yellows for medium. This is because as the signal gets farther away from the radio the signal levels drop lower and lower. Finally at the end we have the green hexes that are the low signals. To get the total number of coverage points? Add all the hexes up.

Note* The coverage provided will be vastly different per install location. Any obstruction such as homes and trees will cause decrease of coverage points.

In the example above there's a total of 128 coverage points, just counting the colors we added. But in reality we need to count all the hexes. I’ve done this and we cover a total of 150 hexes, and that gives us around 1,176 coverage points. As of today Jan 16th, 2024. You could multiply your coverage points by 2.42 to get an estimate of what your rewards in mobile tokens could be. In our case 2,845.9 Mobile tokens per day.

Indoor units

Now onto indoor units such as the indoor wifi and indoor cbrs. They function a bit differently. Actually it's much easier to understand.

Let’s start with the indoor wifi. It only covers 1 hex and is worth 400 coverage points. Yeah, it’s that simple. You can apply the same math as before using the 2.42 value to estimate around 968 Mobile tokens.

The indoor cbrs unit is a bit different. It  covers 7 hexes. With the center hex being worth 400 coverage points, and the first ring around it 100 coverage points each. In the end this unit gets 1,000 coverage points. Same as above, 2.42 = around 2,420 Mobile tokens.

That’s the basics to coverage points. But wait! There's more… A complex part actually. It’s overlapping coverage. If you haven't grasped how the basics work above, I suggest re reading it because this is a more advanced topic, it’s important to understand above to be able to follow along.

Advance topic: Overlapping Coverage

Let me explain how overlapping coverage works. There are penalties for installing radios that overlap coverage.

No overlap: full rewards

It is not 25% reduction on 1 radio anymore, hip105 changed this 👉 https://github.com/helium/HIP/blob/main/0105-modification-of-mobile-subdao-hex-limits.md

1 overlap: you get 50% of the coverage points per overlapping hex

2 overlap: you get 25% of the coverage points per overlapping hex

3 overlap: you get no coverage points per overlapping hex

The overlap is based on signal level per hex. So let's say radio 1 has a high signal(16 coverage points) level per hex and radio 2 has a medium(8 coverage points). Radio 1 will get the full coverage points while radio 2 will get 50% in that hex. So instead of getting 8 coverage points, radio 2 is now getting 4 coverage points on that hex.

Now. Let’s dive in!

For sake of ease let's pretend all hexes going forward are high signals worth 16 coverage points each for the pink radio.

Here’s our first radio, again white hex being where the radio is placed, and it's pointed in the direction the pink arrow is, about 150 degrees.

We should already understand this. There's about 150 hexes covered here, and we said each hex is 16 coverage points in this example. That’s a total of 2,400 coverage points.

Now it's about to get complicated so pay attention. We are going to add another radio (430h). This time facing the opposite direction, north-ish in green.

Do you see the overlap? There's a bunch of it. The green radio is facing north but the houses around it are really affecting the signal. But let’s look into the overlap.

Let’s break down this image. Remember, the pink radio has high level signa(16cp each hex)l in all hexes, and the green radio has medium(8 cp per hex). So the pink radio is not going to lose any rewards. The green radio will though.

First off the hexes that will get full rewards for the green radio are the ones with red dots. Because it does not overlap with anything.

There are 26 hexes without overlapping coverage for the green radio. We said before its medium signal so lets times 26 hexes by 8 coverage points = 208

Now let's count the overlap. With the blue/cyan dots in the hexes.

There are 93 overlapping hexes here. So we should get 744 coverage points (93x8cp) + the red dots that was 208cp, gives us a total of 952 coverage points. But its not like that.

Since these are overlapping and the pink radio has stronger signal, we are going to lose coverage points here. It’s 1 level of overlap so we are going to keep 50% of our coverage points on those 93 hexes. Essentially each hex is now worth 4 coverage points for the green radio where overlap is. Let’s do the math. 93 x 4 coverage points = 372.

The overlapping coverage made us lose 372 coverage points. So all together the green radio has a total of 580 coverage points. (we added back the 208 from the non overlapping 26 red dots coverage.)

For another example, let's pretend it was the 2nd overlapping radio. We would keep 25% of the coverage points per hex. So our 8 coverage points per hex has now turned into 2. Let's do math. 93 x 2 = 186. Add the 208 from the 26 red dots = 394 total coverage points.

And the easiest of all, if there's 3 levels of overlap here, well all those 93 hexes are worth zero, so we only have a total of 208 total coverage points from the red dots.

Let's recap those numbers because that was a lot of math.

Green radio

If there was no overlap. It would have gotten 952 coverage points.

1 overlapping radio. It would have gotten 580 coverage points.

2 overlapping radios. It would have gotten 394 coverage points.

3 overlapping radios. It would have gotten 208 coverage points.

I want to show another example just to be sure you understand the concept of overlapping coverage.

Here we have 1 430 in green covering a very large area. The radio is where the pin is and facing south-west. This is farmland.

Let’s add a second radio pointing north. In red.

You see all that overlapping coverage in orange?

What I'm trying to say here is there is pretty much no way to avoid overlapping coverage. My personal recommendation is pick 1 or two radios. When you add a 3rd it's really diminishing rewards. But you need to evaluate this per location. You can use the Planner tool to run simulations, while it doesn't support overlapping overage per new simulation you can run 1,2 or 3 of them and visually see the overlapping to judge if it's worth it.

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1 comment

Good explanation. Thank you.

Greg Grundl

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