Vaisala IRIS, User Manual

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3.16 RTI : Range Time Indicator
Figure 22 RTI Example Configuration
RTI displays time along the horizontal axis and the vertical axis displays range from the
radar.
An
RTI can be used for any scan type (for example, PPI , RHI ), but is most useful for manual
scans or "searchlight" scans which are manual scans at a fixed position. Perhaps the best
application is for vertical incidence scanning in which case the
RTI product shows a time-
height cross-section of the atmosphere.
The following example shows an
RTI and a PPI from the same situation. From both pictures,
the maximum range is 50 km (31.1 mi) and the color scale is same. In this case, RTI has been
made from a PPI task rotating 10° per second so the horizontal axis is both seconds from
start and azimuth in tens of degrees. You can see the weak echo region near 220°, starting
from 15 km (9.3 mi) in both. This can be beam blocking, which is probably easier to
recognize in the
RTI .
IRIS Product and Display User Guide M211319EN-H
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