Which scanning indicator is used to plot target data in polar coordinates?

Which scanning indicator is used to plot target data in polar coordinates?

• A. A-scan
• B. Raster
• C. Plan Position Indicator (PPI)
• D. Deflection

Answer: (C)

Radars plot range and bearing on a circular display, using distance from the center for how far away a target is and the angle around the circle for its direction. The Plan Position Indicator is built for that, showing targets as blips around a circular screen with range outward from the center and bearing around the circumference, i.e., polar coordinates (range, bearing). A-scan, by contrast, presents range versus time on a vertical trace and doesn’t convey azimuth. Raster displays use a rectangular scanning format, not a circular polar plot. Deflection refers to how the display beam moves, not to plotting in polar coordinates. So the indicator that plots target data in polar coordinates is the Plan Position Indicator.

Radars plot range and bearing on a circular display, using distance from the center for how far away a target is and the angle around the circle for its direction. The Plan Position Indicator is built for that, showing targets as blips around a circular screen with range outward from the center and bearing around the circumference, i.e., polar coordinates (range, bearing). A-scan, by contrast, presents range versus time on a vertical trace and doesn’t convey azimuth. Raster displays use a rectangular scanning format, not a circular polar plot. Deflection refers to how the display beam moves, not to plotting in polar coordinates. So the indicator that plots target data in polar coordinates is the Plan Position Indicator.