A typical external ground electrode system specified by Motorola R56 include a shelter, tower ground ring (counterpoise), and grounding radial out to the corner fence.
However, this is not always a practical method because there may be multiple carriers on the tower with numerous shelters surrounding the tower within the compound. Therefore, it is not ideal to take prime real estate with tower grounding radials.
In most cases, a fence grounding ring (counterpoise) would be used, as this maximizes the linear feet of grounding wire without disturbing areas required for concrete shelter bases and other support structures. If the soil resistivity report indicates highly resistive soil, grounding radials may be needed at the gate to achieve a low DC resistance less than 5 ohms. Each of the ground rings, including the generator, will have two separate paths to ground that protect the ground system and equipment in the event one of these connections is breached.