New GPS Antenna Cuts Noise Interference

Kurt LawtonGeneral

Hemisphere GPS introduces its new A21 antenna, designed to reduce GPS correction signal signal dropoff that can be caused by electrical ‘noise’ and interference.

With its metal base, lower profile, improved Left Hand Circular Polarization (LHCP) rejection, and ability to filter out an additional 30 decibels of radio band of frequencies, the A21 antenna offers superior noise rejection. The new antenna will track GPS, SBAS (WAAS, EGNOS, etc.) and OmniSTAR(R) L-band signals. The A21 Antenna also features a TNC connector, which has a threaded coupling interface to ensure a secure connection.

“Our new A21 antenna does a better job of mitigating the interference from radios, transmitters, and other peripheral electronic equipment,” said Dr. Michael Whitehead, Chief Scientist for Hemisphere GPS. “This means that even in environments that are typically filled with electronic noise, like an aircraft cockpit, the A21 antenna will provide a constant, steady and reliable stream of GPS data and differential corrections.”

David Habig, a pilot with Dixie Dusters from Itta Bena, MS stated, “In the past, my GPS signal used to drop off when I keyed my radio. I would lose GPS and have to wait for the signal to come back.” In some cases, the GPS signal would be lost for up to 15 seconds because of radio interference. An aircraft can cover a good distance in 15 seconds, and losing a signal for that long can significantly impact the application. Mr. Habig put the new A21 antenna to the test, and was pleased with the results. “I tried to make it lose GPS signal in my turns, but it did not. This is a big improvement. Anyone with interference concerns is going to want this antenna.”

The A21 antenna will begin shipping in May 2009, and will be included in all Hemisphere GPS Air M3(TM), Flying Flagman(R), and LiteStar II(TM) GPS guidance systems. Current Hemisphere GPS Air GLA-3(TM) antenna owners can also upgrade to the new A21 antenna. The A21 antenna features the same mounting footprint as previous Hemisphere GPS Air antennas. The A21 antenna technology will soon be featured in other Hemisphere GPS product lines as well.