A system and method are provided in which each reader may conduct concurrent, yet independent, dialog with multiple tags at the same time using two or more phase channels. The reader itself may communicate with multiple tags via the same antenna, or using multiple antennae where each antenna operates...http://www.google.com.tw/patents/US6952157?utm_source=gb-gplus-share專利 US6952157 - System and method for concurrently addressing multiple radio frequency identification tags from a single reader
