Electromagnetic anechoic box/Shield box/Anechoic chamber
The necessity of a wireless system test has risen by the spread of recent wireless telecommunication equipment as shown in cellular phone, wireless LAN, RF-ID tag and ETC (Electronic Toll Collection system). It is necessary for a wireless test to be performed in anechoic environment in which an external noise is intercepted and a radio wave does not reflect internally. An anechoic chamber (room version of a shield box) is proper facilities but needs a wide space and a huge cost. Especially, the equipment under wireless system test on the production line can not radiate any signal radio wave outside before approval. The shield box satisfies these conditions.