An efficient subspace technique for joint angle and delay estimation of wireless users using circular array

In this paper, we propose a subspace-based approach to estimate the direction of arrival (DOA) and time of arrivals (TOA) of multipath signals arriving at uniform circular array (UCA). The channel estimates from different time slots of TDMA systems have constant path DOA and TOA over the observed period. By virtue of the geometry UCA, uniform circular arrays are ideally suited to provide 360deg coverage in the azimuthal plane rather than uniform linear array. Davis transformation used to adopt channel estimate to be suitable for using MUSIC algorithm