www.radartutorial.eu Radar Basics

High- and Low- Beam

high beam
low beam
high-beam
receiver
low-beam
receiver
power
divider
transmitter

Figure 2: Radar antenna with high- and low- beam pattern

high-beam receiver low-beam receiver power divider transmitter high-beam circulator low-beam circulator Feedhorn for „low-beam”- Chanel Feedhorn for „high-beam”- Chanel
high beam
low beam

Figure 2: Radar antenna with high- and low- beam pattern

The picture shows how the power is fed to the two feed horns. In practice the majority of the power is fed to the low beam in order to achieve the long range performance. A power divider is used to split the power between the two horns. The signal received by the two horns are processed separately thereby achieving detection in one horn even if the alternative horn does not provide coverage.

Antenna of the ATC-Radar STAR-2000
(click to enlarge: 300·361px = 17 kByte)
Figure 1: STAR-2000 with High- and Low-Beam- Feeding of the Antenna