With　the　rapid　development　of　electronics　and　information　technology,　electronics　and　electrical　equipment　have　been　widely　used　in　our　daily　lives.　The　living　environment　is　full　of　electromagnetic　waves　of　various　frequencies　and　energy.　Electromagnetic　wave　radiation　has　evolved　into　a　new　type　of　environmental　pollution　that　has　been　listed　by　the　WHO　(World　Health　Organization)　as　the　fourth　largest　source　of　environmental　pollution　after　water,　atmosphere,　and　noise.　Studies　have　shown　that　when　electromagnetic　wave　radiation　is　too　much,　it　can　cause　neurological　disorders.　And　electromagnetic　interference　will　cause　the　abnormal　operation　of　medical　equipment,　precision　instruments　and　other　equipment,　and　therefore　cause　incalculable　consequences.　Therefore,　electromagnetic　protection　has　become　a　hot　issue　of　concern　to　the　social　and　scientific　circles.