A wireless repeater with features that improve the server-donor antenna isolation including multi-purpose server and donor mounting plates that each carry an antenna feed circuit board and associated antenna elements mounted in a back-to-back arrangement with the duplex repeater electronics board sandwiched between the server and donor mounting plates. To improve the server-donor antenna isolation, one or both mounting plates may include corner, side tabs, which may be asymmetric, and raised walls around one or both mounting plates. In addition, the radomes covering the donor antenna and/or the server antennas may carry one or more parasitic conductors, such as a two parasitic strips arranged in parallel lines or for parasitic strips arranged in a square configuration.