Maximum Likelihood Population Estimator of RFID Tags With Hadamard Footprint
A novel method is proposed that can estimate the tag population in Radio Frequency Identification systems by using a Hadamard code for the sub-preamble of the tag response. The authors formulate the maximum likelihood estimator for the tag population using a given number of the observed footprints. In simulations, the proposed estimator performs considerably better than the conventional schemes. Radio Frequency IDentification (RFID) systems have been viewed with much interest in the field of supply chain management. However, the market is hesitating to employ RFID systems because of the low efficiency with which tags are identified.