Reliability of channel quality in cellular systems based on packet transmission

This paper considers the problems involved in reliable estimation of channel quality in packet based cellular systems. Packet systems reserve channels on an activity basis that allows statistical multiplexing on the air interface. A consequence of this that the autocorrelation function of the C/I decreases rapidly hence reducing coherence time. This in turn reduces the number of samples that can be used to assess the link quality of the channel. An assessment requires knowledge of the distribution from which the samples are taken. The mean and standard deviation of the C/I are calculated for different cluster sizes in macrocell and microcell environments for a mobile moving along specific paths. These are used in conjunction with coherence time and voice activity statistics to determine the reliability of tests performed on link quality samples. Comments are presented on the consequences of these results for the control of mobility functions in packet based systems