Hello, I'm working on some set and forget logging sensors that I would like to give RF comms to, so that driving by the area let them ping in and download there stored memory, say once per day, to once per week, with a payload of about 2KB per day, However i am struggling with which method to choose.
My constraints,
Its powered by a coin cell, I can go for a larger one, but still current and amp hours are limited, (my current device chews an average of 8uA while logging)
Range would ideally be between 85 - 220m, larger is better, but i Understand it generally chews more power,
The receiver will have a nice big supply, and can have amplification. and have an antenna height of about 2m above the ground.
The device will be about 10cm above the ground, clear of grass or other material, a pcb or stiff wire antenna is possible, but not a sma pivot.
And transfer speed is not much of a concern.
So far I have been pointed at the nRF905, however people testing them have given mixed results.
https://www.nordicsemi.com/eng/content/download/2452/29528/file/Product_Specification_nRF905_v1.5.pdfAny thoughts or suggestions?