C - Lublin
C - Lublin
C - Lublin
Create successful ePaper yourself
Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.
connecting smart-transducers into a easily accessible network, with the special<br />
focus on the connection to the network in the wireless way.<br />
DESIGN OF THE WIRELESS COMMUNICATION SYSTEM<br />
The application of wireless transmission in the license-free frequency bands for<br />
communication in short distances is very popular in environmental monitoring<br />
systems as well as in the control of industrial processes. Very attractive are<br />
frequency ranges 433 MHz and 868 MHz called ISM (Industrial, Scientific and<br />
Medical) frequency bands. There are many electronic devices available dedicated<br />
for ISM bands, particularly modern trainceivers integrating radio receivers and<br />
transmitters in the same integrated circuits [3,4]. The ready to apply radio modules<br />
are available for electronic engineers in the form of mounted and tested tiny<br />
electronic boards for the price of only about 10 Euro. The hardware and software<br />
of the radio communication systems should be designed with the following criteria<br />
in mind: (i) minimize the transmission errors, (ii) maximize the radio link range,<br />
(iii) minimize the current consumption (the systems are usually battery operated).<br />
The presented prototype system allows to control the measurement process and<br />
transmission of the soil profile temperature. The software communication protocol<br />
as well as MASTER and SLAVE hardware devices carried out the point-to-point<br />
radio link. The communication protocol can be enhanced to point-multipoint<br />
connection for radio network system.<br />
The functional diagram of the prototype communication system, serving as an<br />
implementation IEEE1451 standard NCAP – Network Capable Application<br />
Processor, is presented in Fig. 1.<br />
Fig. 1. Functional diagram of the prototype soil physical parameters<br />
monitoring system with the wireless communication link<br />
127