Date Added: May 2011
The authors consider a mobile connected to a base station, saving energy by shutting off its transceiver, and they try to answer the fundamental question: what is the optimal sleep policy? Firstly, they study the model from optimal control perspective. They consider off-times (periods of inactivity) of unknown duration. They study the question of scheduling "Waking up" instants in which the mobile communicates with the base station and checks whether the inactivity period is over. There is a cost proportional to the delay from the moment the off-time ends until the mobile discovers it, a (small) running cost while the mobile is sleeping and also a cost for waking up.