ced near the antenna on the rooftop. An example is shown in Figure 13.4. Figure 13.5 shows antennas for two typical macrocell base station installations. A macrocell is usually the first element used in broadband wireless communications systems because it allows for blanket, albeit imperfect, coverage of a populated area. This serves two goals: an operator can claim blanket coverage in its marketing material. It can also minimise Network Topologies, Design and Convergence Figure 13.4 Ericsson's Radio Base Station 6301 (size: 1115x415x536 mm). Reproduced by permis- sion of Ericsson AB [8] Figure 13.5 Two macrocell base station antennas initial capital expenditure, and grow the network with the number of subscribers and traffic. For example the initial network roll-out in the central business district (CBD) of Adelaide may look as shown in Figure 13.6. This roll-out requires minimal investment and as the initial number of subscribers to a new system is low, service quality is acceptable. Subsequent intro- duction of smaller cells may be made in targeted areas as user subscriber traffic grows. The radius of a macrocell depends on two factors: the amount of expected offered traffic at peak time, and the maximum coverage distance of the technology. The former is a function of Broadband Telecommunications Technologies and Management resuvan venue South of Adelaide of Australia King. Australian Adelaide Museum North Tce North Tce North Tce North Tce Rundle Park Comfort Hotel Rundle Rd Adelaide Riviera Prince A Rundle Mall Hindmarsh Square Rymill Park Colle Philip St Grenfell St Currie Currie Light Square Barte Waymouth Eynesbury Senior College Flinders Flinders Christman Brothers Franklin College Oval Wakefield St Grote St Albert Ln Grote St Angas St Angas St Adelaide Gouger Central Market Base station Hume St Carrington Carrington Carrington St Wright West Terrace Cemetery Sturt Caims Gilles Gilbert St Gilles Gilbert St Delhi St South Tce South Tce South South Tce Figure 13.6 A possible initial coverage of Adelaide CBD