A portable RF docking station is detachably coupled to a palm-sized computer to provide extended wireless communication through a radio modem and wireline communication through a wireline modem. Both modems are contained inside the docking station and are powered by rechargeable batteries....http://www.google.de/patents/US5739665?utm_source=gb-gplus-sharePatent US5739665 - Radio modem docking station for palm-sized computer
