Open Access

Tower-Top Antenna Array Calibration Scheme for Next Generation Networks

EURASIP Journal on Wireless Communications and Networking20072007:041941

DOI: 10.1155/2007/41941

Received: 1 November 2006

Accepted: 31 July 2007

Published: 10 October 2007

Abstract

Recently, there has been increased interest in moving the RF electronics in basestations from the bottom of the tower to the top, yielding improved power efficiencies and reductions in infrastructural costs. Tower-top systems have faced resistance in the past due to such issues as increased weight, size, and poor potential reliability. However, modern advances in reducing the size and complexity of RF subsystems have made the tower-top model more viable. Tower-top relocation, however, faces many significant engineering challenges. Two such challenges are the calibration of the tower-top array and ensuring adequate reliability. We present a tower-top smart antenna calibration scheme designed for high-reliability tower-top operation. Our calibration scheme is based upon an array of coupled reference elements which sense the array's output. We outline the theoretical limits of the accuracy of this calibration, using simple feedback-based calibration algorithms, and present their predicted performance based on initial prototyping of a precision coupler circuit for a array. As the basis for future study a more sophisticated algorithm for array calibration is also presented whose performance improves with array size.

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Authors’ Affiliations

(1)
Centre for Telecommunications Value-Chain Research, Institute of Microelectronics and Wireless Systems, National University of Ireland

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Copyright

© Justine McCormack 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.