User's Manual

EA Mobile User Guide
1. Introduction
14
specified route. The EA_Mobile can be set to give an audible signal upon
acquiring meter data so that the driver never has to take his eyes off the road
while the vehicle is in motion.
RF signals and conditions
EA_Mobile range
As a rule, residential gas endpoints within a line-of-sight distance of
approximately 1200 feet of the EA_Mobile should be able to receive interrogation
signals and respond appropriately when the EA_Mobile is in FIFO mode (Note:
the line-of-sight distance for water endpoints may vary based on installation
parameters). In GEO or L/L mode interrogations are limited to the size of the
window. Certain fixed or transient conditions in the immediate environment
surrounding the endpoint or EA_Mobile may increase or reduce this range.
Obstructions
Line-of-sight (no obstructions between the EA_Mobile antennas and the
endpoint) provides the optimum transaction range. Although the EA_Mobile can
typically read endpoints through walls and fences, any obstacles between the
EA_Mobile and the endpoint will reduce the range at which successful
communications may be conducted. Metallic obstacles (vehicles, trash cans,
metal sheds, etc.) in the path will severely limit interrogation range.
Transaction capacity
The EA_Mobile can interrogate one EA_Gas module endpoint a second,
retrieving 35 daily reads in addition to the current read in extremely dense
populations under ideal conditions.
Interrogation window
The interrogation window is a virtual space that simply defines which endpoints
the EA_Mobile will seek to read at any given time. Depending upon the selected
reading mode, the interrogation window may include:
• Endpoints having Lat/Lon coordinates that are determined to be within the
interrogation window of the EA_Mobile at the moment (Lat/Lon mode).
• All endpoints, regardless of Lat/Lon coordinates or proximity to the
EA_Mobile (FIFO mode).
• A combination of the above, seeking those Lat/Lon endpoints determined to
be within the interrogation window at the moment and in addition also
seeking all endpoints without Lat/Lon coordinates regardless of proximity to
the EA_Mobile (GEO mode).
Adjusting interrogation window size
The user can manually increase or decrease the interrogation window in order to
change the scope of the EA_Mobile’s search for endpoints. A smaller
interrogation window would be desirable, for example, in urban areas where the
endpoint population is extremely dense. In rural areas where endpoints are few
and far between, a larger Interrogation window may be used to detect endpoints
at a greater distance.