Foreword by Professor Simon Saunders
The compelling need for in-building wireless systems derives directly from the needs of the people who use wireless–and that means, increasingly, all of us. We spend most of our time inside buildings, whether in the office or at home, at work or at play. Typically at least two-thirds of voice traffic on cellular networks originates or terminates inside buildings, and for data services the proportion is still higher–probably in excess of 90%.
Yet for too long, most indoor service has been provided from outdoor systems requiring high transmit powers, major civil engineering works and using a relatively large amount of spectrum to serve a given traffic level. This makes great sense for providing economical initial coverage to a large number of buildings and for ‘joining the dots’ to enable wide area mobility. However, ‘outside-in’ thinking is ‘inside-out’, from a technical and practical viewpoint, when attempting to serve users with very high quality and coverage expectations, and for delivering high data rate services within limited spectrum. Buildings offer their own remedy to these challenges, by providing signal isolation from nearby systems and enabling the fundamental principle of cellular systems–that unlimited capacity is available from limited spectrum if the engineering is done right.
Despite these compelling benefits, in-building wireless systems have hitherto been a poor relation of the ‘mainstream’ macrocellular network operations. ...