Digital Wireless Data Communication Network for Distributed Measurement Applications: System Architecture and First Experimental Results

In this paper the architectural design of a measurement system for remote sensing, based on ‘ad hoc’ Wireless Local Area Network (WLAN) concept is proposed. The system is conceived as a Code Division Multiple Access (CDMA) Spread Spectrum (SS) network operating in the unlicensed Industrial-Scientific-Medical (ISM) frequency band (2.4 GHz to 2.5 GHz). It makes use of a specific and extremely simplified communication protocol, whose characteristics allow simple implementation, without preventing of taking advantage from the processing gain associated with the waveforms. Then the critical hardware element of the system, the modem, is identified and potential applications of the complete system are discussed. The most meaningful aspects strictly related to the modem design are discussed and the hardware solutions are presented. Finally the experimental results descending from the test activity performed on some critical functional blocks of a couple of prototypes under design are discussed.