Performance of Channel Carrying for Handoff in a DCA Cellular Network

Abstract

Channel carrying allows a mobile station to continue the use of its currently occupied channel when it hands off to a new cell. Since in a dynamic channel assignment (DCA) system, generally, any channel can be used by any cell, channel carrying can be more easily implemented than in a fixed channel assignment (FCA) system which supports channel carrying through borrowing channels or extending channel reuse distance. Therefore, this paper investigates different channel carrying strategies maybe used in the distributed timid DCA scheme with the seamless handoff policy (DCA-DT/SLH), namely, channel carrying first (CCF) and channel carrying last (CCL). This study shows that (1) CCL generally outperforms CCF; (2) in DCA-DT/SLH without channel carrying, handoff calls may suffer higher dropping probabilities than new calls if no priority is given to handoff calls while channel carrying can easily avoid such undesirable situation; and (3) channel carrying in DCA-DT/SLH is comparable and even better than the guard channel (GC) in FCA and can also slightly improve the performance of GC in DCA-DT/SLH.