Backtracking and dynamic bit-shield anti-collision algorithm in RFID system

In a radio frequency identification system, The lower identification efficiency problem of system brought by multi tags collision has become the bottleneck problem of the application of RFID technology. At present, the backtracking and dynamic binary search anti-collision algorithm is a better anti-collision algorithm, but in the complex and high-speed multi tags RFID system, the efficiency of identification is still difficult to meets the requirement. In this paper, the backtracking and dynamic bit-shield binary search anti-collision algorithm was proposed on the basis of backtracking and dynamic binary search anti-collision algorithm. During the search, the tags ID before the collision bit has been recognized by reader were shielded. The reader classification search tags based on bit-shield characteristics of tags. Only the information after collision-bit that the reader hasn't known was returned. The stack memory area was set up according to principle of “first in last out” in reader. The tags ID can be recognized quickly and accurately. The algorithm reduces the times to search tags by reader and reduce the amount of data sending information between reader and tags. The efficiency of identifying tags is improved.