Influence of the transmission medium quality on the automatic meter reading system capacity

This article determines the influence of the telecommunication transmission medium´s quality, expressed by the probability of failed single-try transmission, on the capacity of the automatic meter reading system. Failed message transmission leads to the necessity of retransmission, with possible multiple retransmissions. This causes the prolongation of average time required for collecting the information from the great population of meters, reducing the capacity of reading expressed in meters per hour being read. This work continues the analysis published by S. Mak et al. (1995), but also expands it by including the influence of the transport medium´s limited quality. In the automatic meter reading systems, one can use networks with radio relays and power line carrier (PLC)-based devices. Our analysis is partly based on the assumption that the PLC medium has much lower quality than the radio, causing most of the transmission errors occur on the PLC itself. The result of the analysis is the processing prolongation factor g, which depends on the statistic parameter of single-try retransmission probability only. This kind of model enables the explanation of disproportion amongst the local probabilities of retransmission and the general probability observed in the entire network, as recognized and documented by L. Selander (1999) . In the end, we determine the automatic system´s reading capacity limit.