A mathematical programming approach for W-CDMA radio planning with uplink and downlink constraints

The mobile telecommunications industry throughout the world is currently shifting its focus from second-generation (2G) to third-generation (3G) UMTS technology. Service providers and manufacturers are investing in the design and manufacture of advanced mobile Internet/multimedia-capable wireless networks based on the wideband code division multiple access (W-CDMA) radio access platform. Previously, we studied the radio planning problem considering separately uplink and downlink direction and we proposed algorithms and a mathematical programming model for locating and configuring base stations aiming at maximizing coverage and minimizing cost (E. Amaldi et al., Proc. PIRMC´02, vol.1. p.315-19, 2002; Proc. IEEE VTC Fall 2002, vol.2. p.768-72, 2002; Proc. WCNC´03, 2003). We now describe an overall model which considers both uplink and downlink directions. We also propose a Tabu search algorithm and a simple power control mechanism to reduce drastically the computational time required to find an approximate solution of the mixed uplink and downlink model. Finally, some experimental results obtained for realistic instances are reported and discussed.