Advanced Features

The coverage of an area and the accuracy is evaluated by the Dilution of Precision mathematical model.

Dilusion of Precision (DOP)

The DOP provides a gain factor for how much the position error is amplified at a given point of space by the anchors' geometry. The lower the DOP value, the better the accuracy at the output. In the RTLS Planner, you have an option to evaluate your anchor geometry by calculating the DOP.

The calculation is requested by pressing the "" button on the control panel. The icon will be changed in relation to what is currently being displayed.

  • - DOP in both axes (x and y);
  • - DOP in x-axis;
  • - DOP in y-axis;
  • - nothing;

There are some limitations you should keep in mind before you start with the calculation.

Blink to Anchors

For 2D location, there have to be at least 4 anchors getting the blink from a position of calculation to be able to calculate a DOP of the position. For the 1D location, there have to be 2 anchors.

Whether the anchor is getting the blink is influenced by two factors.

  1. The first factor is distance. The maximum allowed distance is 25 meters (diagonally for 2D cell) for the 2D location using anchors Omni or 30 meters for the 1D location using anchors DirectFive.

  2. The second factor is wall obstruction. Wall obstruction is calculated from the top view in 2D, so the height of the walls does not matter.

Sync Between Anchors

Once the calculation knows which anchors are getting the blink, it will check each anchor as the potential master and its visibility to other anchors getting the blink (same rules as before).

Finally, the anchors that are used for calculation are:

  • the closest anchor (master)
  • with the biggest number of slaves (all selected from the anchors getting the blink)

DOP Calculation Example

Below you can find an example of the DOP calculation in the RTLS Planner.

Be sure that you added tag height to your plan. If not, you should add it via buttonin the control pannel.

The area Final is covered by four anchors Omni (2D location). The aisles between the shelves are covered by anchor DirectFive (1D location.)

Other Examples

All green lines mean that there is a direct line of sight between the two ends of the line. They have been curved for the sake of visualization, so there are no overlapping lines.

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