RFID Reader Localization Using Hard Decisions with Error Concealment

This paper presents an efficient localization algorithm
for reader in radio frequency identification (RFID) networks.
In the proposed algorithm, [R2;3]it is assumed that no
channel state information is available at the reader, and thus,
the backscatters of all RFID tags are converted to hard decisions
using an energy detector. The performance of the obtained
estimated location is improved using an error concealment algorithm
that utilizes the fact that adjacent tags are expected
to produce similar decisions. The final location estimates are
obtained using a maximum likelihood estimator, which is derived
while considering the imperfect sensing and transmission
processes and its solved using Particle Swarm Optimization. The
performance of the proposed algorithm is evaluated in terms
of the root mean square error using Monte Carlo simulation,
and compared to other well-established localization algorithms.
Moreover, Cramer-Rao lower bound is derived to assess the
efficiency of the new estimator. The obtained results show that
the proposed algorithm may outperform other well established
estimators by about 26:5%.