Choke ring antenna

Patent Diagram of a Choke Ring Antenna[1]
Choke ring antenna at a DGPS Reference Station

A choke ring antenna is a particular form of omnidirectional antenna for use at high frequencies. It consists of a number of conductive concentric cylinders around a central antenna. Due to its delicate construction, it is often enclosed in a protective cover or radome when placed outside and exposed to the elements.

Choke ring antennas are notable for their ability to reject multipath signals fading from a source. Since the path that a signal takes from a transmitter to receiver can be used to measure the distance between the two, this makes it highly suited for GPS and radar applications. In a GPS ground based receiver, a choke ring antenna can provide millimeter precision measurements[2] for surveying and geological measurement applications.

The choke ring design originated at the Jet Propulsion Laboratory.[3]

See also

Notes

  1. ↑ US Patent 6,040,805 - Patent for Low Profile Ceramic Choke , one specific type of choke ring antenna.
  2. ↑ http://www.trimble.com/infrastructure/gnss-choke-ring-antenna.aspx - Catalog page for a Trimble choke ring antenna.
  3. ↑ http://www.javad.com/jns/technology/Single-Depth%20Low-Multipath%20Choke%20Ring.html - A basic description of choke ring antenna benefits and limitations.

External links