Open Access

Optimal Design of Nonuniform Linear Arrays in Cellular Systems by Out-of-Cell Interference Minimization

EURASIP Journal on Wireless Communications and Networking20072007:093421

DOI: 10.1155/2007/93421

Received: 13 October 2006

Accepted: 11 July 2007

Published: 22 August 2007


Optimal design of a linear antenna array with nonuniform interelement spacings is investigated for the uplink of a cellular system. The optimization criterion considered is based on the minimization of the average interference power at the output of a conventional beamformer (matched filter) and it is compared to the maximization of the ergodic capacity (throughput). Out-of-cell interference is modelled as spatially correlated Gaussian noise. The more analytically tractable problem of minimizing the interference power is considered first, and a closed-form expression for this criterion is derived as a function of the antenna spacings. This analysis allows to get insight into the structure of the optimal array for different propagation conditions and cellular layouts. The optimal array deployments obtained according to this criterion are then shown, via numerical optimization, to maximize the ergodic capacity for the scenarios considered here. More importantly, it is verified that substantial performance gain with respect to conventionally designed linear antenna arrays (i.e., uniform interelement spacing) can be harnessed by a nonuniform optimized linear array.


Authors’ Affiliations

Dipartimento di Elettronica e Informazione, Politecnico di Milano
Center for Wireless Communications and Signal Processing Research (CCSPR), New Jersey Institute of Technology, University Heights


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© S. Savazzi et al. 2007

This article is published under license to BioMed Central Ltd. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.