Design Of Lightning Protection Measures For Medium Wave Radio Transmitting Antenna-feeder Systems

With the rapid development of broadcasting technology,more and more channels are being broadcasted by radio stations,and the medium-wave launch pad has become particularly important.Usually,there are a large number of electronic devices and electronic systems such as automatic control,signal processing and medium wave transmitter in the station,but the antenna-feeder system is vulnerable to lightning damage because the position of the transmitter station is generally in a higher position.Therefore,lightning protection is an important problem that has puzzled radio transmitter stations for a long time.In order to ensure high-quality and uninterrupted broadcast of broadcast programs,lightning protection must be applied to the transmitting station,and the antenna-feeder system should be well maintained to ensure the safety performance of medium wave transmitter in lightning environment.On the basis of a comprehensive field investigation and analysis of the existing lightning protection measures for the four-frequency public standby tower antenna-feeder system of Dalian 303 Broadcasting Station,this paper designs and implements its lightning protection system.The main work is as follows:(1)Based on the field investigation of the antenna feeder system of Dalian 303 broadcasting station,through analysis and research,the specific problems of the antenna-feeder system in direct lightning protection,induction lightning protection,surge protection and lightning warning are found.(2)According to the actual demand,the comprehensive lightning protection scheme of Dalian 303 broadcasting station was designed,including the front-end inductor and capacitor of the standby tower relay,the feeder lightning arrester,the network matching and the new electronic monitoring system.Phase offset,filtering and other issues are solved through the redesign of the sky-tuned network,and the sky-tuned network itself also has a certain lightning protection effect.(3)The lightning protection system,matching network,Transmitter Room network,feeder arrester,antenna and feeder electronic monitoring system,medium wave broadcasting transmitter monitoring and management integrated system are installed and debugged by using vector network analyzer and other instruments and equipment.(4)The lightning protection system after the transformation was tested by lightning simulation,transmitter index test and network stability test to verify the lightning protection performance of the system after the transformation.Through technical transformation and implementation,the lightning protection performance of the Dalian 303 broadcasting station antenna-feeder system has been significantly improved,which provides a strong guarantee for the safe and reliable operation of the medium wave launching platform.