Communication Coverage

In regions or events of limited communication infrastructure, emergency responders and other mission teams need to establish mobile communication networks. Often, every minute of extra response time is critical, as is awareness of potential communication gaps in the field.

GDA’s Field Geometric Health (FGH) tool, developed under DARPA funding, was designed to understand the capabilities of a sensor or device network at a given time and to make recommendations that would improve the network’s capabilities in the future. FGH incorporates local terrain and environmental sensor data, accounting for elevation and current weather conditions in the calculation of communication coverage. Users can view uncovered regions, as well as suggested locations for additional repeaters to optimize coverage or robustness of the communication network.

Use Case

With many wildfires in regions without cellular service, firefighters rely on VHF radios and repeaters placed throughout a fire’s extent to communicate. Repeater coverage depends on factors such as topography, environmental conditions, and repeater height. Substantial gaps in coverage are likely, due to the need for more repeaters to follow a changing fire extent, and also due to the mountainous terrain common around many of the serious fires in the West.

Simulated Repeater coverage for the Dixie Fire, August 5th, 2021. Each colored pixel represents the probability of at least one repeater having coverage at that location. Over the 12 hours preceding this satellite data snapshot, a change in winds led to rapid movement of the fire to the Northeast, hence the repeaters being positioned mostly Southwest of the fire at this moment in time. Dixie Fire satellite data from NOAA CLASS. Repeater location data from

In wildfire firefighting, FGH will model real-time VHF radio coverage over a fire’s extent. With the current location of repeaters in the field, users will have a probabilistic coverage map, as well as report areas with bottlenecked coverage and low redundancy. Firefighters and Incident Command can know before deployment if teams should expect to be out of communication range. Radio repeater placement will be heavily-dictated by terrain, distance, and time constraints. Furthermore, wildland fires change sufficiently rapidly that firefighters may deploy into regions with limited or zero radio coverage. Understanding connectivity before deployment is a critical improvement for both field personnel and Incident Command so that expectations of communications are understood and necessary plans may be made.