Design and implementation of a miniaturised, low power wireless sensor node

A miniaturised wireless sensor node with a high level of modularity is presented. A transceiver module with a size of 10 mm by 10 mm, operating in the 433/868 MHz frequency bands has been developed. An interface layer provides a regulated power supply from a rechargeable battery, USB battery charging, and USB communications to support the transceiver module. The node has been designed to support very low power operation for applications with low duty cycles, with a sleep current of 3.3 muA transmission current of 10.4 mA, and reception current of 13.3 mA. The small size combined with the level of modularity and energy efficiency results in the suitability of this system to a wide variety of potential applications. This paper discusses the design goals of the node, the decisions made during the design process, and characterisation of the resulting implementation.