The invention provides a device for enhancing performance of a portable cellular phone within a mobile vehicle. The device includes a housing located within the vehicle into which a portable cellular phone may be placed. The housing includes an exterior layer that reflects noise signals and an interior layer that reduces reflection of communication signals within the housing. Signals are transmitted between the cellular phone and an exterior-mount transceiver by means of a wireless RF coupling device that is contained within the housing and connected to the exterior-mount transceiver using a coaxial cable.