PRIMUSr 880 Digital Weather Radar System
5.Radar Facts
RADAR OPERATION
The PRIMUSâ 880 Digital Weather Radar works on an echo principle. The radar sends out short bursts of electromagnetic energy that travel through space as a radio wave. When the traveling wave of energy strikes a target, some of the energy reflects back to the radar receiver. Electronic circuits measure the elapsed time between the transmission and the reception of the echo to determine the distance to the target (range). Because the antenna beam is scanning right and left in synchronism with the sectoring sweep on the indicator, the bearing of the target is found, as shown in figure 5- 1.
The indicator with the radar is called a plan- position indicator (PPI) type. When an architect makes a drawing for a house, one of the views he generally shows is a plan view, a diagram of the house as viewed from above. The PPI aboard an airplane presents a cross sectional picture of the storm as though viewed from above. In short, it is NOT a horizon view of the storm cells ahead but rather a MAP view. This positional relationship of the airplane and the storm cells, as displayed by the indicator, is shown in figure 5- 1.
A28- 1146- 102- 00 | Radar Facts |
|
