Comments on "An efficient demand-assignment multiple-access scheme for satellite mobile radio dispatch networks" [with reply

Abstract

The commenter calls the attention of the authors of the above paper (see ibid., vol.38, p.204-10, Nov. 1989) to very closely related earlier work that deals with the essential issues in a more fundamental way. Specifically, these consider traffic capacity comparisons for demand-assigned, multiple-access systems that use slotted or unslotted ALOHA-type request channels. The analysis and results are directly applicable to any arrangement of channels in an FDMA (frequency multiple access)/TDMA (time division multiple access) multiplex and also account for the possibility that requests cannot be served because specific assets are busy although message channels are available. The authors agree that using the blocked-calls-queued service discipline to increase traffic capacity has been analyzed in the previous work cited. They point out that this call-processing discipline is particularly useful in the satellite mobile radio dispatch application examined because of the dispatcher bottleneck. Another important issue in mobile satellite demand-assignment multiple-access for radio dispatch is the large fraction of signaling overhead relative to the very short holding time of individual mobile radio calls. The authors note that their paper offers the techniques of multiple-calls batch-processing and pipeline signaling as effective measures in dealing with this issue. >