What type of radar beam provides precision ground mapping?

A fan beam is designed to provide precision ground mapping due to its specific geometry and the way it scans the ground. This type of beam emits a wide but narrow vertical pattern, allowing it to cover an extensive area while maintaining high resolution in a particular direction. The fan beam's shape is particularly beneficial for mapping terrain features, as it can obtain detailed information over a broad swath of land without losing resolution.

This beam type can effectively capture multiple returns from different elevations and terrain types, making it ideal for applications in topography, vegetation mapping, and similar tasks where detailed ground information is essential. By sweeping the fan beam across an area, radar systems can obtain intricate imagery and measurement data, hence facilitating accurate ground mapping.

The other types of beams, such as spot beams or wide beams, do not provide the same level of precision and detail for ground mapping because they may either focus on a smaller area without the extensive coverage or spread the energy too broadly, which dilutes the detail received from the ground.