High power amplifier or site power sharing: comparison of two low cost solutions to boost UMTS downlink capacity

The expected increase of asymmetric traffic in wireless 3G networks is likely to generate capacity limitations in down link (DL). In this paper we investigate and compare two DL capacity enhancement techniques alternative to densification or multi-carrier, viz. the use of 40 W power amplifiers, and the use of site power sharing, i.e. the possibility for one sector to use the available power from power amplifiers of other co-sited sectors. Using a dynamic simulator on a real urban network, we show that both solutions allow to improve the DL capacity of the network. Very interestingly we show that for admission and upholding probabilities greater than 85%, both methods are almost equivalent. They should hence be compared according to their implementation and maintenance costs.