Novel Low-Complexity and Power-Efficient Techniques for Fast Collision Detection in Wireless Sensor Networks

In Wireless Sensor Networks (WSNs), it is imperative to utilize the most power efficient techniques to prolong the lifetime of a sensor node. Minimization of power consumption in WSN's has been discussed extensively in literatures. Usually, central nodes (e.g. cluster head nodes) in WSNs consume large amount of power due to the necessity to decode every received packet regardless of the fact that the transmission may suffer from packets collision. Unlike other power consumption techniques, instead of decoding every received signal at the central nodes which consume too much power, we propose a suite of novel, yet simple and power efficient technique to detect a collision without the need for full-decoding of the received packet. Our novel approach aims at detecting collision through fast examination of the signal statistics of a short snippet of the received packet via a relatively small number of computations over a small number of received IQ samples. Hence, operating directly at the output of the receiver's analog-to-digital-converter (ADC) and eliminating the need to pass the signal through the entire demodulator/decoder line-up. We present a complexity and power-saving comparison between our novel techniques and conventional full-decoding (for a select coding scheme) to demonstrate the significant power and complexity saving advantage of our techniques. In addition, we also demonstrate how to tune various design parameters in order to allow a system designer multiple degrees of freedom for design tradeoffs and optimization.