An Efficient Anti-collision Protocol Using Bit Change Sensing Unit in RFID System

A tag collision problem, which is one of core issues when building the RFID system, reduces the efficiency of identifying tags. To solve the tag collision problem, various protocols have been proposed and studied. Almost all the tree-based algorithms aim at generating the unique prefix, and identifying tags as quickly as possible. However, the existing protocols, when many tags are placed on the same range, are increasing the number of query , and expending a great deal of time in identifying tags. In this paper, we proposed the QT-BSC protocol to reduce the number of query. The protocol creates a prefix by using bit change sensing unit and time slot. That is, the proposed protocol is designed so as to send the bits from the next bit of prefix to the bit which has the other value. Consequently, as sending bit group which can easily be tracking a new prefix, this method can reduce the number of query. As a result of a simulation, this paper shows that less time is needed for identifying tags by reducing the number of query-response more than query tree and 4-Ary query tree.