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Choke ring antenna
From Wikipedia, the free encyclopedia
A choke ring antenna is a directional antenna designed for reception of GNSS signals from satellites. It consists of a number of concentric conductive cylinders around a central antenna.
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The first choke ring antennas were invented at JPL;[2] since 1989 they have been improved and extended by many companies.[citation needed]
Due to its intricate construction, it is often enclosed in a protective cover or radome when placed outside and exposed to the elements.[citation needed]