Patent ID: 8653946

Claim:
A Radio Frequency Identification (RFID) reader, comprising: a random value generator to generate a random value for each RFID reader to select a channel at different delay time; a reader controller configured to adaptively select a counter value for generating the random value, and when the listen time as long as the random value generated in the random value generator is ended, make a command to select a channel for communication with a tag, and control an operation to acquire information from the tag; an anti-collision unit configured to control to prevent collision among a plurality of tags and transmit a communication result between the RFID reader and the tag to the reader controller; a reader transmitting unit to generate a reader command message determined by the anti-collision unit, encode the reader command message, and modulate the reader command message; a reader receiving unit to demodulate and decode a tag signal received through an antenna and report a tag response status to the anti-collision unit; and a channel operation controller configured to select a channel to be used for the communication with the tag upon receipt of a command of the reader controller, wherein the channel operation controller comprises: a Listen Before Talk (LBT) mode controller to execute LBT control; and a random access mode controller to control a random access method.