In-Building Wireless: Past, Present and Future

More than two-thirds of mobile traffic occurs inside buildings, and this proportion is growing as high-rate data applications such as mobile TV are taken up, yet most of the resources of a mobile operator are occupied with building and managing the outdoor network, with in-building systems typically deployed only in large public buildings and large corporate headquarters. In meeting the coverage and capacity demands of indoor traffic, operators need new technology solutions which perform well, yet are easy to deploy and manage in large numbers at reasonable cost. This lecture surveys the growing needs for dedicated in-building systems, describes existing approaches such as distributed antenna systems and explains the new technology developments, including femtocells and distributed base stations, which are expected to give operators an opportunity for expanding services into smaller office environments and in the home.