Abstract
Recently, wireless telecommunication devices have been used with worldwide spread of the mobile phone, wireless local-area networks (WLAN) and UHF-Radio frequency identification (UHF-RFID). Therefore, EMI problems have been so serious. In the case of indoor use, wireless telecommunication environment is deteriorated by multiplex reflection interference. That interference has to be controlled for improving wireless communication circumstance. Especially, it is thought that the improvement of the multi-path environment is indispensable to secure reliability in UHF-RFID system.
In this paper, ultra thin microwave absorber as an improvement technology of the multi-path environment for UHF-RFID system is described. Additionally, a transparent feature is given to this absorber. Because the microwave absorber should not increase the blind area of the observation camera in the region for which UHF-RFID system is used (around the entrance gate of offices or warehouses). In an actual warehouse, the verified result about the effectiveness of tag identification probability improvement with this absorber is also presented.
