Effects of discontinuous transmission on the performance of a WCDMA cellular system

We investigate the side effects of DTX (discontinuous transmission) on the performance of a WCDMA radio interface with SIR-based closed-loop power control. The aim of DTX is to reduce the energy consumption of the mobile terminal and the total interfering power in a cellular system; we show that this technique can also lead to a temporary performance degradation when the interfering terminals turn on their data channel after some frames of inactivity. The main parameters that characterize the dynamics of the DTX mechanism are described and their effects are investigated. We also propose a suitable variation to the DTX mechanism which reduces the unwanted effects.