Long range, low power, Low latency RF module

Hi,

This is my first post in this forum. I am looking for an RF OEM module with a range about 1 mile, low warmup up times from sleep (10s of ms or better). My network would be a star configuration witth very low data payload transmissions.

If some sort of software stack for time synchronization is avaialble that would make life a whole lot easier.

My understanding of the Xbee series has been large warmup times (min 100ms) which would not be very suitable for my network.

My specifications are flexible to adapt to whats available, but im trying to find something thats as close as possible.

Thanks for your time.

Please advice