The DB(BR)Gxxx series differential barometer/altimeter (patent pending) is a higher accuracy version of the EM(BR)Gxxx.  This product  integrates the DBOxxx module in a ruggedized unit with built-in power source, GPS tracking and Bluetooth (rover only) capabilities. DB(BR)xxx are lower cost variants without GPS.
 
The unit provides atmospheric pressures and derived elevations at a rover using corrections transmitted from a stationary base.   In traditional systems elevations are calculated based on pressure readings for a stand-alone unit and are subject to the errors inherent with environmental changes in pressure.  Some applications of this versatile engine include indoor elevations, building pressurization monitoring, multi-node telemetry networks and UAV altitude references.