Pinwheel broadcast paradigm in supporting energy-saving mobile devices

Because of the limited bandwidth and restricted number of channels in the wireless access environment, the broadcast paradigm has become an important technique for accessing messages. Energy saving is an important issue in the mobile computing environment. In this paper, we propose a multichannel broadcast paradigm that constructs the broadcast channels according to the access frequency of each type of message in order to save energy in mobile devices (MDs). The pinwheel scheduling algorithm (PSA) presented in this paper is used to organize all types of messages in the broadcast channels in the most symmetrical distribution in order to reduce both the tuning time and the access time. The performance of the proposed mechanism is analyzed, and the improvement over existing methods is demonstrated numerically. The results show that the proposed mechanism is capable of improving both the tuning time and the access time due to the presence of skewness in the access distribution among the disseminated messages, When the number of message types increases, both the tuning time and the access time can be further improved as long as a small number of broadcast channels are added. Copyright (C) 2009 John Wiley & Sons, Ltd.