Sea water aquarium underwater communication

For CircuitPython issues, ask in the Adafruit CircuitPython forum.

Moderators: adafruit_support_bill, adafruit

Please be positive and constructive with your questions and comments.
Locked
User avatar
HorstO
 
Posts: 34
Joined: Fri Jan 09, 2015 7:46 pm

Sea water aquarium underwater communication

Post by HorstO »

Hi!
I need to communicate with a raspberry pi that is sealed in an underwater casing in a sea water aquarium. The maximum distance of data transmission would be < 30 cm (raspberry pi <-> salt water <-> tank wall <-> air). I have read that WiFi and Bluetooth would not work even for small distances under water (and worse for salt water). Is that correct?

Does anyone have good ideas for alternatives? I was thinking of routing data first to a LoRa module or even try IR, but I wonder if anybody tried something similar and succeeded?
(I read viewtopic.php?f=57&t=156071&p=769914&hi ... on#p769914 - but no consensus was reached).

Thanks!

User avatar
adafruit_support_bill
 
Posts: 88096
Joined: Sat Feb 07, 2009 10:11 am

Re: Sea water aquarium underwater communication

Post by adafruit_support_bill »

Radio waves are seriously attenuated by salt water, athough the distance here is not that large. You might get them to work fine at 30cm.

If that does not work, you might want to look into IR. It does work through salt water and the TSOP38238 receiver is relatively easy to interface to the Pi.

https://learn.adafruit.com/ir-sensor
https://learn.adafruit.com/using-an-ir- ... dia-center

User avatar
HorstO
 
Posts: 34
Joined: Fri Jan 09, 2015 7:46 pm

Re: Sea water aquarium underwater communication

Post by HorstO »

Thanks, cool, I will give it a try.

User avatar
adafruit_support_bill
 
Posts: 88096
Joined: Sat Feb 07, 2009 10:11 am

Re: Sea water aquarium underwater communication

Post by adafruit_support_bill »

Here is an interesting article on a related subject. They use lasers for the long distance communication through the water. But they still use WiFi underwater for the shorter distance from the laser transceiver to the smart-phone.

https://techcrunch.com/2020/07/15/resea ... -networks/

Locked
Please be positive and constructive with your questions and comments.

Return to “Wireless: WiFi and Bluetooth”