A power consumption analysis of tight-coupled WLAN/UMTS networks

The proliferation of WLANs and the ubiquitous coverage of cellular networks have resulted in several integration proposals towards 4G networks. Among them, the tight-coupled WLAN/UMTS architectures promise seamless service continuity to users and enhanced network performance. Most of these solutions assume that only one interface is active at a time, while much fewer consider the concurrent use of both WLAN and UMTS interfaces as this is expected to consume more energy. This paper presents a detailed description of power consumption for the two different tight-coupled WLAN/UMTS approaches based on the states of the wireless devices. A simple analytical model is provided for estimating the power consumption in each approach, while a simulation model measures the power needs for more complicated cases. Moreover, the enhancement due to a power-saving mechanism in WLAN is also assumed in the system and useful deductions are provided about the average power consumption per mobile terminal.