Abstract: The object of the invention is to facilitate the entry of a sensor node and the adoption of a protocol in the existing sensor network system effectively utilizing limited resources of radiocommunication. To achieve the object, the following are provided. A sensor node has a radiocommunication unit that transmits a measured value sensed by a sensor and an identifier of a sensor node as binary measured data. A base station has a radiocommunication controller that receives the measured data from the sensor node, a wire communication controller that transmits the received measured data to a server, a conversion definition information selector that selects conversion definition information corresponding to the identifier included in the measured data out of preset plural conversion definition information and a conversion engine that converts the binary measured data to measured data in a text format based upon the selected conversion definition information.

Abstract: The object of the invention is to facilitate the entry of a new type of sensor node and the adoption of a new protocol in the existing sensor network system effectively utilizing limited resources of radiocommunication. To achieve the object, the following are provided. A sensor node has a radiocommunication unit that transmits a measured value sensed by a sensor and an identifier of a sensor node as binary measured data. A base station has a radiocommunication controller that receives the measured data from the sensor node, a wire communication controller that transmits the received measured data to a server, a conversion definition information selector that selects conversion definition information corresponding to the identifier included in the measured data out of preset plural conversion definition information and a conversion engine that converts the binary measured data to measured data in a text format based upon the selected conversion definition information.