A Distributed Medium Access Control (D-MAC) protocol has been proposed to support high-rate Wireless Personal Area Networks (HR-WPANs) by the WiMedia Alliance. The WiMedia D-MAC solves the problems of the IEEE 802.15.3 MAC caused its centralized architecture. However, due to mobility of WiMedia devices in multi-hop environment, DRP (Distributed Reservation Protocol) reservation conflicts happen frequently among devices within three-hop range distance. To solve this problem, we propose a new DRP reservation scheme using a new 2hop range DRP Availability IE for three-hop mobility support in WiMedia MAC with ultrawideband (UWB) technology. It is shown by simulation results that throughputs of devices at frequent three-hop range DRP reservation conflicts are largely increased.