ISA100.11a is a standard that is being developed my ISA that defines a radio specification for industrial process control and sensors. It’s based off IEEE 802.15.4-2006, which operates in the 2.4 GHz ISM band using DSSS. It defines the method of mesh networking to be used that allows the radios to set up routing between radios to allow all radios in the network to communicate with each other. This allows a greater range, as each radio can act as a router for other radios.
This is simular to current wireless technologies such as WiressHart, DigiMesh, Dust Networks TSMP, and Zigbee; but is an open standard which should allow more interoperability between devices and includes some more advanced networking and low power features.
I’ve looked into all of these radio technologies, and ISA100.11a is the one that holds the most promise. At least for what I looking for.