Polarisation-angle-delay estimation using crossed-dipole array for DS-CDMA systems

In this paper the use of a crossed-dipole array is proposed in joint space-time channel estimation for asynchronous multipath DS-CDMA systems. The polarisation diversity offered by such an array, unlike linearly polarised arrays, is shown to provide a better and more consistent estimation which is less sensitive to the signal polarisation. By utilising the polarisation information inherent in the received signal, the accuracy and resolution of the estimation is also significantly improved. To avoid a multidimensional search into the polarisation space, a computationally efficient polarisation-angle-delay estimation (PADE) algorithm is also presented, where the polarisation parameters, if required, can be obtained by solving a set of analytical equations.