One thing that I found counter-intuitive is that building a device that periodically receives data wirelessly is generally more expensive on the battery than a device which periodically transmits.
Naively, I assumed that it must take more power to transmit than to receive, which is true on an instantaneous basis, but false on an average basis.
A device that wakes up every so often, transmits, then goes to sleep can use very little average power as compared to a device that must constantly have the receiver powered up to listen.
Naively, I assumed that it must take more power to transmit than to receive, which is true on an instantaneous basis, but false on an average basis.
A device that wakes up every so often, transmits, then goes to sleep can use very little average power as compared to a device that must constantly have the receiver powered up to listen.