Ultra low power MAC layer wake-up frame scheme for low cost and low traffic wireless sensor networks

Wireless sensor networks, as a key enabling technology of Ubiquitous Computing, have been a booming research topic in the recent years. Upon designing a low-cost wireless sensor device, power consumption is one of the most important issues, because cheap batteries are normally the power suppliers. Since the RF transceiver is one of the biggest power consumers in such a sensor device, enabling the RF transceiver to sleep as much as possible is the preferred method to save power, which is normally realized by MAC layer duty cycle scheduling. This dissertation proposes aMAC layer wake-up-frame scheme to wake up an RF transceiver on-demand to minimize the standby waiting time in receive mode to save power. Analytical and simulation results show that, for a low-traffic wireless sensor network, this scheme gives significant system battery lifetime gain compared to the traditional methods. Furthermore, the combination of the wake-up-frame scheme and a complementary lowpower MAC protocol is discussed. Analytical computation and simulation prove that the combined scheme achieves a further optimized solution in the sense of power-saving, while other important system parameters, such as response time and channel efficiency, are limited to a reasonable range.