Location Cell Size

Based on the dimensions of the location cell, you have to consider several factors when designing the anchor deployment and tag placement.

If you look at the example bellow, you can see how the anchors are able to cover a smaller cell with the radio signal. As can be seen, the signal reaches the borders where the anchors are and the most reliable performance will be achieved in the center of the area.

Another example is shown in next figure. We can see that the dimensions in both axes have increased and that also the resulting location area has shifted. Because of the directivity of the antennas, we can see that the radio coverage is again at its best in the center, but tends to drop on the sides. However, if the system is designed so that the tag does not reach the borders and move only in the location area, the performance will be at its best.

Generally, if we consider larger location cells, the tag placement becomes more critical. If the dimensions of the cell increase, the tag must be placed on a visible spot so it has a clear line of sight to the anchors. With smaller location cells, the tag placement is less critical but with increasing dimensions it must be well considered. Several practical examples can be found in this table:

LengthWidthHeight of the AnchorsAnchor TiltTag PlacementNotes
20 m20 m3.5 mNo tilt

Human body

Tag should be at the most “visible” place possible, e.g. shoulder, back of the neck
20 m20 m8 m16 degMaterialsPlease consult with our technical support placement of the tags
25 m25 m7 m11 degHuman bodyAdditional anchors might be necessary (human body significantly attenuates UWB signal)
24 m24 m6 m10 degForklift roofTag mounting on the forklift roof ensures good LoS for forklift tracking

If you are not sure about the correct tag placement, please contact our Service Desk.