We consider the uplink of a multicarrier code-division multiple-access (MC-CDMA) network and assume that the base station is endowed with a uniform linear array. Transmission takes place over a multipath channel and the goal is the estimation of the directions of arrival (DOAs) of the signal from the active users. In a multiuser scenario, diﬃculties are primarily due to the large number of parameters involved in the estimation of the DOAs which makes this problem much more challenging than in single- user transmissions. The solution we propose allows estimating the DOAs of diﬀerent users independently, thereby leading to a signiﬁcant reduction in the system complexity. In the presence of multipath propagation, however, estimating the DOAs of a given user through maximum-likelihood methods remains a formidable task since it involves a search over a multidimensional domain. Therefore, we look for simpler solutions and discuss two alternative schemes based on the SAGE and ESPRIT algorithms.
|Autori:||A. A. D'AMICO; MORELLI M; L. SANGUINETTI|
|Titolo:||DOA estimation in the uplink of multicarrier CDMA systems|
|Anno del prodotto:||2008|
|Digital Object Identifier (DOI):||10.1155/2008/851726|
|Appare nelle tipologie:||1.1 Articolo in rivista|