The use of wireless network for distributed measurement applications

The connectivity of sensors to the central processing unit of the measurement system becomes a primary problem, especially if a large numbers of long analog wires should be installed in harsh and hazardous environments. A solution to this problem can be the adoption of a wireless link. In this paper the architectural design of a measurement system for remote sensing, based on ´ad hoc´ Wireless Local Area Network, is described. The system is conceived as a Code Division Multiple Access (CDMA) Spread Spectrum (SS) network operating in the Industrial-Scientific-Medical (ISM) frequency band (2.4 GHz to 2.5 GHz). The principal aspects related to the data communication device design are discussed and the hardware solutions are presented. The first results of devices characterization are very satisfactory and in a good agreement with the estimated one.