Assembly of super compact wireless sensor nodes for environmental monitoring applications

This paper presents the integration and the assembly of MEMS sensor with RF-IC and flexible RF-antenna, which is expected for the production of super compact and maintenancefree wireless sensor nodes for applications in `green' sensor networks, e.g. environmental monitoring, electric power consumption controlling. To reduce its size to the lowest possibility, structure and layout of the sensor node was investigated, and then 2 prototypes for humidity and temperature measurement were assembled with the size of a few mm without RF-antenna, and 2×5 cm with flexible RF-antenna. Electric power consumption of the prototype sensor nodes during one cycle of measurement and data transmission was studied. Life-time of the coin battery, which was used as the power source, was calculated and discussed. The practical evaluation results demonstrated that above proposed structure and assemblytechnologies are promising as a platform for super compact and flexible `green' sensor nodes production.