u/Declanjs

I was thinking maybe they could be for noise monitoring, or a kind of alarm? No text I could see anywhere.

I found two of these in Sydney, both in the City of Sydney council area. Here's street view:

https://maps.app.goo.gl/BDstATT8AXzx3ARbA

https://maps.app.goo.gl/4C4kegq5voCbmKw96

It has a few components on the pole:

* Solar Panel

* Cone-looking thing in mesh

* Cone is connected to a box by a tube/hose

* Black box on the bottom of the pole.