e-Dif technology is capable of achieving GPS accuracies of a few feet without the need for a differential signal broadcast.

What is e-Dif?

e-Dif provides positions that are very accurate in relation to a temporary reference location. The receiver gathers continuous data from satellites for 20 minutes and then computes a matching differential corrector for that specific location -- a process called calibration. This provides a “localized correction,” correcting mostly for local atmospheric conditions. Calibration automatically starts upon power-up, and may per performed either while stationary or driving. During the calibration process, the receiver must have a clear view of the sky for the duration of the calibration process (20 minutes). Once e-Dif is running, the receiver continually adjusts corrections to match changing conditions on the GPS signals caused by the atmosphere.

Once a Phoenix 200 is activated to use e-Dif, there are no more subscription fees.

Things you should know about e-Dif as related to the Phoenix 200:

1. e-Dif produces internal differential GPS corrections based upon patented Ionosphere delay modeling algorithms.
2. You must have at least 5 GPS satellites in view while using e-Dif. If you drop down to below 5 satellites, the receiver will have to re-converge.
   1. Convergence time requires 20 minutes.
   2. It is recommended to turn the receiver off at the end of each day or if GPS visibility is blocked for any period of time. This will ensure that your accuracy is maintained.
3. You are not required to sit still while e-Dif converges on the Phoenix 200. You can simply start up the machine and drive to the field. The convergence should be completed by the time you arrive.

How It Works

e-Dif generates internal differential corrections based on the starting location. The differential corrections are modeled over time and applied to the GPS data in order to maintain a very consistent relative position. The operator can use e-Dif over long time periods with a minimal drift in accuracy or return to the starting location at any time to update the differential corrections.

How Can I Get It?

Talk to your Raven Distributor about Raven's Phoenix 200 GPS receiver and the optional e-Dif upgrade.

The Phoenix 200 kit can be ordered from Raven with or without e-Dif.

Features:

Accurate
e-Dif typically maintains less than a 3 foot drift over a period of forty minutes. Because the accuracy variations are very gradual, e-Dif provides very accurate alignment between successive swaths.

Reliable
If other differential services may be limited or expensive, e-Dif is the solution you are looking for. However, In locations where differential services may be free and readily available e-Dif is a reliable back-up differential option.

Which Raven receivers support e-Dif?

Currently, Raven's Phoenix 200 GPS receiver supports e-Dif as an optional upgrade.