The quad-helix omni (QHO) designs bring the advantages of the characteristic quad-helix antenna radiation pattern to mobile ENG uplink/downlink applications. The QHO features carefully designed helix parameters to optimize performance characteristics for such applications.
The QHO antenna provides a circularly polarized omni-directional radiation pattern with peak gain of 4 dBi at 30 degrees above the horizon, and then decreasing gain, with no nulls, as the elevation angle increases to the overhead 90 degree direction. The shape of this radiation pattern naturally compensates for the change in path loss as a mobile transmitter moves from the overhead direction out towards the horizon. Good coverage is provided in this way from approximately 20 degrees above the horizon to the overhead direction.