A Spread Spectrum Modular Can Be Used For Locomotives Wireless Data Transmission

For its strong resistance to multipath interference and interception rate and other significant advantages,spread spectrum communication technology is widely used in military communications.With the third generation mobile communication technology, more and more spread-spectrum communication technology used in civilian communications.China Railway, particularly in the southwest,mountains and more corners,more tunnels, more mountains of geographical features make the wireless communication channel is very bad. Kinds of unexpected interference will influence on the reliability of wireless data transmission,thus affect the safe operation of locomotives.At present, China locomotive application of wireless digital communications is mostly 450MHZ digital radio,the test showed that the radio transmission will appear in the tunnel signal interruption,and weak co-channel interference resistance. A large number of experiments and studies have shown that only 900MHz band wireless signal can transmit the tunnel.On the basis of describeing in detail ofthe theoretical spread spectrum ommunication technologyc and the analysis of the locomotives wireless data transmission, the paper takes the advantages of spread spectrum communication technology used in wireless data transmission module locomotive, applied with a 900MHz spread spectrum wireless data transmission program module,part of 900MHz RF design and the upper and lower frequency and antenna selection and application programs,completed the Stanford Teleco programmable spread spectrum chip company STEL-2000A as the core,with STC89C52 MCU control,including high-speed A/D,D/A conversion of the baseband spread spectrum processing part of the hardware design, and module debugging, testing results meet the expected requirements.