The External Antenna PA-850AT is free of charge, and it is included in Main Unit packing.

If the distance between IR wireless conference main unit and microphone units is not far, and have not any obstructions, antenna can be connected to the “ANT” connector of IR main unit rear panel directly. If the distance is far or have some obstructions between main unit and microphone units, please try to install the antenna close to the center of conference site, then use a 50Ω coaxial cable to connect to IR main unit, and the coaxial cable should be less than 20 meters. And the antenna should try to far away from metal objects.