Reducing power consumption by utilizing retransmission in short range wireless network

Low-power issues become critical when the networked computing devices depend mainly on non-AC power sources such as batteries or self-generated power. In the application of using short-range wireless networks to convey low-speed but important information, low power consumption becomes a top design consideration in wireless design. Traditionally, signal strength level is fixed during the entire time of communication to maintain a certain acceptable error rate. A new approach is proposed in this paper to explore the potential and practicality of decreasing the signal strength, thus reducing the total energy consumption. Although the error rate of one frame at the DLL layer increases, it is compensated by retransmission. And it is shown in this paper both theoretically and experimentally that the power consumed could be lowered, without incurring a higher frame loss rate. An adaptive power-adjusting algorithm is proposed to allow power and energy reduction during signal transmission. Experiments are conducted using GloMoSim, up to 71.3% reduction in power can be achieved.