Spatial Efficiency Metric for Wireless Networks Based on Channel Resource Usage

Over the last decades a lot of metrics for spectrum efficiency have been developed. Most are defined in the context of a specific application area and seldom take the spatial dimension of the spectrum into account. This paper surveys key metrics from literature and discusses their potential usage for modern wireless networks. A new spectrum efficiency metric, the spatial efficiency, is introduced to cover single- and multi-link scenarios in wireless local area networks. The metric is based on the usage of shared resources and incorporates the spatial dimension as a key driving factor for efficiency. Based on general aspects of communication-, antenna- and information theory, the metric is widely system independent. Furthermore, an IEEE 802.11ax application case is presented to show the usage of the metric. A general limitation on communication capacity across a given spatial volume is discussed in the appendix.