A wireless door intrusion detection assembly including a magnet component installed on a door, and a fixed magnetic contact wireless transceiver component installed on a door frame corresponding to the door, opposite the magnet component, the fixed magnetic contact wireless transceiver component including a two-way transceiver element operable for two-way wireless communication between the fixed magnetic contact wireless transceiver component and an intrusion alarm system, an antenna facilitating the two-way wireless communication between the fixed magnetic contact wireless transceiver component and the intrusion alarm system, and an antenna ground reference plane, opposite the antenna.