Abstract—In this paper, an improved localization method
named Three-Uniform-linear-arrays Localization (TUL) is proposed
for patient track systems. Three receivers adopting smart
antenna technique cooperate with each other to locate the
patients using angulation positioning method. In order to be able
to track patients in environment with high patient density, a high
resolution direction-of-arrival (DOA) estimation algorithm for
the co-existence of non-circular and circular signals is proposed.
Firstly, the maximal and common non-circularity rated signals
are preliminarily estimated. Secondly, based on the noise space
block matrix, the DOA of these signals are re-estimated with
high accuracy. Then the covariance matrix of the maximal and
common non-circularity rated signals are reconstructed. The
contributions of these signals are eliminated after performing
a subtraction operation on the covariance matrix of the received
data and only those of circular signals remain. Finally, the
DOAs of circular signals are obtained. Results of simulations
and real tests demonstrate the effectiveness and performance of
the proposed algorithm.