A wireless sensor node for condition monitoring powered by a vibration energy harvester

A complete wireless sensor node transceiver with 85.5 µW measured average power consumption is presented. The sensor node implements an asynchronous beacon-detection based duty cycle control architecture to reduce power consumption and avoid the need for timing synchronization between nodes, a common issue in sensor nodes. The transceiver includes a duty-cycle timing control block to minimize power consumption; an LO-less, TDMA-capable, addressable beacon receiver; an FDMA-capable transmitter; and a low-power, universal sensor interface. The proposed sensor node, implemented in 130 nm RF CMOS technology, achieves low power consumption and a high degree of flexibility without requiring calibration or the use of BAW or SAW filters. The sensor node is experimentally demonstrated to operate autonomously from the power provided by a piezoelectric vibration energy harvester with dimensions of 27 × 23 × 6.5 mm3 excited by 4.5 m/s2 acceleration at 40.8 Hz.