Advice Improving esphome connections in Garden

Hardware
1

Hi Guys,

I have recently setup a number of esphome sensors in my greenhouse, running of a 12v solar system which is about 40m away from the unifi outdoor ap which is on the top of the shed with pretty much direct line of sight to the greenhouse.

I was hoping that this would give me a great reliable connection to the various sensors. However, I find that they are often listed as unavailable in Hassio, so I’m assuming they are dropping on and off the network from time to time. I have set the esphome sensors with static IP’s as that’s supposed to reduce dropouts. Apparently my signal strength of the wemos D1’ sensors in -89db :frowning:

So I’m now wondering what else I can try to improve connectivity in this location. Any advice would be much appreciated.

2

You can purchase esp ‘pro’ boards with external antenna connectors. Or you can add your own: How to add an external antenna to an ESP board

Read my last post about FCC though.

For a reliable connection you should be aiming for -67dBm or better. For IoT’s low data rates this can be relaxed a bit to about -70dBm.

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1 Like
3

Thanks @tom_l I’ll give that a go,

4

To get you in the ballpark you are going to need a (89 - 70) = 19dBi antenna. 12 to 15dBi would probably do.

5

Glass is surprisingly hard to penetrate with radio signals.
There is no way to run a cable in there with POE to drive a small AP?

6

Only if it has metallic tinting or energy efficiency coatings. Otherwise it has next to no attenuation.

In this study we have shown that different types of coated window panes exhibit great differences in RF attenuation from approximately 10 dB to 30 dB, over the 1 – 18 GHz range, as compared to almost 0 dB for traditional clear float glass.

7

That is not my experience with any kind of RF.
I have a wifi AP in my window and it has a very low reception in the garden where I can see the antennas.
If I move the AP to the open door I get max reception.

Same thing at work, we use “pagers” to send messages to truck drivers using (I believe) 433 MHz.
We had it in the window and had problems with range so we moved it 3 feet to where it’s sitting behind a brick wall.
Range is better now.

There is no visible metal in any of those windows.
Perhaps there is something else, but both a window in domestic house and a large warehouse from different years have the same problem/solution.

8

Your windows must have some sort of insulation efficiency coating on them. Read the scientific paper I linked to. Normal float glass has little to no effect.

I have an AP in my dining room that easily reaches my back gate through the bay windows (30m away still getting -67dBm). Opening or closing the windows makes no difference.