Symbol synchronisation implementation for low-power RF communication in wireless sensor networks

Speckled Computing is a novel vision of a wireless sensor network consisting of small nodes which can sense, compute and network wirelessly. The nodes will individually have limited power and processing resources, but together will form a powerful processing system. Electrical power resources at such a volume are severely restricted, and as such design decisions are made with low-power as the first priority. This work examines the use of Manchester encoding in the digital transceiver to reduce the complexity of symbol synchronisation. A Manchester decoder has been implemented which has the useful property of being tolerant to oscillator inaccuracies, allowing a cheap and low-power clock source to be employed. A realistic implementation of the decoder using rectangular pulse-shaping and an oversampling ratio of 8 allows an on-chip oscillator tolerance of more than 11%.