Patent ID: 8242891

Claim:
An estimating system comprising: a power supply status estimating means for, within a detection region which includes more than one transmitting devices, each transmitting device of said transmitting devices being affixed to a corresponding detection object, said detection object being detected by a reading device, estimating a power supply activation status of said transmitting device accompanied by a migration of said detection object; a status estimating means for estimating a status of said transmitting device accompanied by the migration based upon said estimated power supply activation status of said transmitting device and an operational history of said transmitting device; and an operation estimating means for determining an operation of said transmitting device based upon the status of said transmitting device responding to a command sent by the reading device, wherein said operation estimating means determines whether said transmitting device is unidentifiable based on the number of said transmitting device having replied to the command, and wherein said operation estimating means, when the number of said transmitting device having replied to the command is two or more, determines that said transmitting device is unidentifiable.