Which scan type is used to cover a rectangular area by sweeping horizontally and vertically?

• A. Circular
• B. Unidirectional
• C. Raster
• D. TWS

Answer: (C)

It’s about how the radar pattern fills a rectangular field by moving the beam across each row and then stepping down to the next row. In a raster approach, the beam sweeps horizontally to form a scan line, finishes that line, steps slightly vertically, and repeats across the next line. This back-and-forth, line-by-line motion creates a grid that covers the entire rectangular area.

Circular scanning, in contrast, rotates the beam around in all directions, producing a circular footprint rather than a rectangle. A unidirectional sweep moves in one direction only, leaving gaps in the perpendicular dimension. Track-while-scan focuses on maintaining a target track while continuing to scan, not on filling a rectangular area.