Besson, Olivier and Bidon, Stéphanie and Larue de Tournemine, Cécile Robust approaches to remote calibration of a transmitting array. (2010) Signal Processing, 90 (5). 1373-1381. ISSN 0165-1684
|
(Document in English)
PDF (Author's version) - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader 321kB |
Official URL: http://dx.doi.org/10.1016/j.sigpro.2009.09.008
Abstract
We consider the problem of estimating the gains and phases of the RF channels of a M-element transmitting array, based on a calibration procedure where M orthogonal signals are sent through M orthogonal beams and received on a single antenna. The received data vector obeys a linear model of the type y ¼ AFg þ n where A is an unknown complex scalar accounting for propagation loss and g is the vector of unknown complex gains. In order to improve the performance of the least-squares (LS) estimator at low signal to noise ratio (SNR), we propose to exploit knowledge of the nominal value of g, viz g. Towards this end, two approaches are presented. First, a Bayesian approach is advocated where A and g are considered as random variables, with a non-informative prior distribution for A and a Gaussian prior distribution for g. The posterior distributions of the unknown random variables are derived and a Gibbs sampling strategy is presented that enables one to generate samples distributed according to these posterior distributions, leading to the minimum mean-square error (MMSE) estimator. A second approach consists in solving a constrained least-squares problem in which h ¼ Ag is constrained to be close to a scaled version of g. This second approach yields a closed-form solution, which amounts to a linear combination of g and the LS estimator. Numerical simulations show that the two new estimators significantly outperform the conventional LS estimator, especially at low SNR.
Item Type: | Article |
---|---|
Audience (journal): | International peer-reviewed journal |
Uncontrolled Keywords: | |
Institution: | Université de Toulouse > Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE) Other partners > Laboratoire de recherche en télécommunications spatiales et aéronautiques - TéSA (FRANCE) |
Laboratory name: | Département d'Electronique, Optronique et Signal - DEOS (Toulouse, France) - Signal, Communication, Antenne et Navigation - SCAN Laboratoire de recherche en télécommunications spatiales et aéronautiques - TéSA (Toulouse, France) |
Funders: | Thales Alenia Space |
Statistics: | download |
Deposited On: | 11 May 2010 15:28 |
Repository Staff Only: item control page