So I have been wondering about wireless sensor networks and home automation for a while. I wanted to know how low I could really push down the price of bi-directional sensor network.
I have these specifications:
- Each node costs less than $6, not including battery
- Each node lasts at least three months on an NiMh AA.
- Bi-directional, data rate not important
- Star topology - one master. Mesh network not necessary, but would be nice.
- Max range 100m
As far as I can tell, using XBee + Arduino just to measure an analog value is complete overkill at ~$45. I hear you can use Xbees by themselves but they are still expensive. Is there some cheap hardware built just for this purpose?