Power considerations when using high capacity data storage on wireless sensor motes

Abstract

In recent years the onboard storage on wireless sensor motes has grown very dramatically, going from Kilobytes (KB) of available space to Gigabytes (GB). This massive increase has primarily come from the addition of support for micro or mini Secure Digital (SD) flash cards on the nodes. This extra storage capacity has led to new use cases for sensor motes which result in fewer data transmissions as a result of more in network aggregation and processing of the sensor data. The primary motivation for using this approach is that writing data to, and then reading data from the SD card, aggregating and processing this data before transmitting smaller packets, should be much more power efficient than transmitting the raw data using the onboard radio. We investigate the power profiles of applications that use SD cards for this purpose versus those that do not in order to determine if there is in fact any power savings, and if so, exactly how much energy can be saved.