Assessment of the benefits of introducing a HSDPA carrier at 900MHz

The roll-out of UMTS/HSPA networks in 900MHz band offers the possibility of bringing 3G and mobile broadband services to new areas with fewer base station sites and of improving indoor coverage in existing UMTS coverage areas. This paper presents the benefits in term of savings on site numbers and on network-related costs provided by the roll-out of a mixed-frequency UMTS network (networks with carriers operating at 900 and 2100MHz) instead of a single UMTS2100 network. These results are presented for dense urban, urban, suburban and rural areas and for three demand scenarios. Despite the higher reductions on site number achieved for lower demand scenarios, savings higher than 30% are found even in higher demand scenarios. Regarding costs savings, higher savings are obtained in the green field roll-out scenario. Lower cost savings are achieved in the brown field scenario but the introduction of a UMTS900 layer results in a more cost efficient solution than maintenance of the single frequency UMTS2100 network.