CHANNEL OCCUPANCY TIMES AND HANDOFF RATE FOR MOBILE COMPUTING AND PCSNETWORKS

This paper presents a study of channel occupancy times and handoff rat e for mobile computing in MC (Mobile Computing) and PCS (Personal Comm unications Services) networks, using general operational assumptions. It is shown that, for exponentially distributed call holding times, a distribution more appropriate for conventional voice telephony, the ch annel occupancy times are exponentially distributed if and only if the cell residence times are exponentially distributed. It is further sho wn that the merged traffic from new calls and handoff calls is Poisson ii and only if the cell residence times are exponentially distributed , too. When cell residence times follow a general distribution, a more appropriate way to model mobile computing sessions, new formulae for channel occupancy time distributions are obtained. Moreover, when the call holding times and the cell residence times have general (nonlatti ce) distributions, general formulae for computing the handoff rate dur ing a call connection and handoff call arrival rate to a cell are give n. Our analysis illustrates why the exponential assumption for call ho lding time results in the underestimation of handoff rate, which then leads to the actual blocking probabilities being higher than the block ing probabilities for MC/PCS networks designed using the exponential d istribution approximation for call holding time. The analytical result s presented in this paper can be expected to play a significant role i n teletraffic analysis and system design for MC/PCS networks.