Tag Identifiable Probability Study While Reader Collision Occurs

Present studies on reader collision problem of RFID are commonly based on an assumption that if intersection areas exist between interrogation range of different readers, reader collision problem will confuse the tags within the intersection area and make them unable to communicate with any reader. On the contrary, the reader-to-tag collision phenomenon is detailedly analyzed in this paper, a new probability model based on the communication protocol of RFID is proposed, the probabilities that tags involved in reader-to-tag collision can be identified by both readers or only can be recognized by one of them, or even can not be identified by any reader are exactly calculated. According to this model even two readers interrogate the tag in the intersection area simultaneously, tags still can be identified by both readers with a relative high probability, and the probability that the tag can not be identified by any reader is quite low.