RF Venue Blog - Finding Signal In The Noise

Visualizing Directional and Nearfield Antennas in Central Park

Written by Alex Milne | Apr 8, 2015 8:44:28 PM

To compare the effects of two different types of antennas (and the effectiveness of the RF Spotlight at reducing sources of interference), we traveled to New York City in search of something most professionals avoid: crowded spectrum.

We brought a camera, a wireless mic, and some other equipment and camped around 59th and 6th, just inside Central Park.

A passive coax switch fed one RF Spotlight and one CP Beam to a spectrum analyzer. The switch and analyzer let us visualize and compare what a wireless microphone receiver would "see" if either of these two antennas were attached at this location.

With the CP Beam, the signals and noise floor within the antenna's pattern are amplified (under normal circumstances, a good thing if pointed at mic transmitters). With the Spotlight, the noise floor melts away, leaving nothing but signal, loud and sweet.

The unique radiation pattern of the Spotlight creates a "bubble" (as we often say) of coverage that envelopes proximate transmitters while attenuating competing RF outside its boundaries, resulting in vastly improved signal-to-noise ratio.