半波振子结构在井下5G辐射场中的安全性分析

Safety analysis of half wave oscillator structure in underground 5G radiation field

GB 3836.1-2021《爆炸性环境第1部分设备通用要求》规定,爆炸性环境中射频设备的射频阈功率不得大于6 W,该规定引自欧盟标准,缺乏试验验证,严重制约了5G技术在煤井下的应用。为了重新评价矿井5G通信设备辐射电磁波能量的安全性,分析得出金属结构耦合电磁波产生放电的形式应为低压分断电路电弧放电;分析了金属结构耦合电磁波产生的放电能量,选择最易耦合电磁波的半波振子结构为研究对象,通过比较得出等效半波振子等价直流放电电路产生的放电能量大于等价高频放电电路产生的放电能量,从而将分析金属结构耦合电磁波放电的安全性转换为分析金属结构的等效半波振子天线等价直流放电电路的安全性。选择直流本安电路的安全性判别原则来判断等效半波振子等价直流放电电路的安全性,通过计算放电功率和能量,得出5G射频设备辐射功率不大于10.5 W时,将不会点燃爆炸性的瓦斯气体,因此,可将5G通信系统射频基站的安全辐射功率提高到10.5 W。

GB 3836.1-2021 Explosive atmospheres-Part 1:Equipment-General requirements stipulates that the RF threshold power of RF equipment in explosive environments shall not exceed 6 W.This regulation is derived from EU standards and lacks experimental verification,seriously restricting the application of 5G technology in mines.In order to reassess the safety of electromagnetic wave energy radiated by 5G communication equipment in mines,it is analyzed that the form of discharge generated by metal structures coupling electromagnetic waves should be low voltage breaking circuit arc discharge.The discharge energy generated by metal structures coupling electromagnetic waves is analyzed.The half wave oscillator structure that is most easily coupling with electromagnetic waves is selected as the research object.Through comparison,it is found that the discharge energy generated by the equivalent DC discharge circuit equivalent half wave oscillator is greater than that generated by the equivalent high-frequency discharge circuit. Therefore, the analysis of the safety of metal structure coupling electromagnetic wave discharge can be transformed into the analysis of the safety of the equivalent DC discharge circuit of equivalent half wave oscillator antenna of the metal structure. The safety judgment principle of intrinsically safe DC circuit is selected to judge the safety of the equivalent DC discharge circuit of equivalent half wave oscillator . By calculating the discharge power and energy, it is concluded that 5G RF equipment will not ignite explosive gas when its radiated power is not greater than 10.5 W. Therefore, the safe radiated power of RF base station of 5G communication system can be increased to 10.5 W.