ABSTRACT
In the brief history of mobile networks, the concept of cellular networks or a cellular system is not novel, having already been informally introduced by D. H. Ring in 1947 [1,2]. The concept proposed a new idea for increasing the network capacity by more efficient reuse of the spectrum resources through densifying the existing macrocellular network elements. Several years and publications later (e.g., [3-7]), patents for mobile communication systems with cellular network capabilities started to appear. Among the first of these was a patent by a Bell Labs engineer, Amos E. Joel, Jr., for a mobile communication system [8]. Joel proposed the idea of cell switching, that is, transferring the call connection from the coverage area of one base station (BS) cell to the coverage area of the neighboring cell. This enabled automatic cell reselection and released the used spectrum resources back to the other users in the first cell. It also suggested a way to locate a user within the cellular network using location areas, thus making it possible, for example, to route a call to a mobile network user to the correct cell in the network by knowing roughly the location of the mobile phone in the network.
