The 3rd Generation (3G) Universal Mobile Telecommunications System (UMTS) radio access network relies upon novel, more flexible and efficient communication methods, a consequence of which is that novel modelling and planning approaches become of prime importance to the network's rollout success. In this chapter, we will briefly consider the historical developments of radio network modelling and planning, thereby highlighting the need for a more modern approach to the subject. Equally importantly, we alert the reader to the limitations of modelling tools. The chapter concludes with a discussion of the advantages, disadvantages and limitations of both manual and automated optimisation processes.
HISTORICAL ASPECTS OF RADIO NETWORK PLANNINGOne of the co-editors was working as a radio network planning consultant for one of the emerging UMTS networks in the late 1990s. It soon emerged that his point of view on network planning for 3G was surprisingly different from that of the operator's engineers. A likely explanation for this would be that neither party, at that time, had had any practical experience of UMTS network planning. On the one hand was an academic UMTS background and on the other was the operators' extensive GSM network planning experience. Once discussion started among both parties, it turned out that both sides had very different points of view on virtually all network planning aspects, because they simply viewed the network using very different planning parameters. While the more academic approach recognised the multitude of parameters influencing a UMTS radio network, the concern of the operators was more the appropriate selection of 3G base site locations and their static configuration. The operators' view was largely driven by the suggestion of some consultants that the main issue in 3G network planning was capacity and coverage, which, because no real planning tools were then available, were derived either analytically or using manual measurement regimes.
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IntroductionSo what, really, is network planning? And, is network optimisation part of network planning or is this included in network optimisation? This book is going to give the answers to the above questions and, hopefully, to many more. As will also become apparent, neither the academic nor the operators' initial approach was right or wrong. Without going into too much detail, let us dwell upon a couple of issues related to network planning and optimisation.Let us start with the choice of an appropriate base site location. Traditionally, the choice has been to locate base sites at the intersects of a triangular grid, thereby covering hexagonally shaped cells. There are many reasons why this approach has been successfully applied to network planning problems, the main reason being its analytical simplicity. Indeed, such a cell-layout uniformly covers any flat surface and is also well approximated by omnidirectional base site antenna elements. The choice of a hexagonal cell shape is further justified when...
