By Topic

Matrix conjugate gradients for the generation of high-resolution spectrograms

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$33 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

2 Author(s)
M. Zoltowski ; Sch. of Electr. & Comput. Eng., Purdue Univ., West Lafayette, IN, USA ; E. Santos

When only a limited number of snapshots is available for estimating the spatial correlation matrix, a low-rank solution of the MVDR equations, obtained via a small number of iterations of conjugate gradients (CG), can yield a higher SINK than the full-rank MVDR beamformer. The primary issue addressed in this paper is whether the unity gain constraint in the look direction should be enforced a-priori via the use of a blocking matrix, constituting steering dependent conjugate gradients (SD-CG), or effected a-posteriori through simple scaling of the beamforming vector, constituting steering independent conjugate gradients (SI-CG). It is proven that the two methods yield exactly the same low-rank beamformer. This is an important result since the construction, and application to the data, of a blocking matrix for each "look" direction represents a very substantial computational burden. A simplified expression for the power estimate obtained with the SI-CG beamformer is also presented. Simulations verify the efficacy of the theory.

Published in:

Signals, Systems and Computers, 2004. Conference Record of the Thirty-Seventh Asilomar Conference on  (Volume:2 )

Date of Conference:

9-12 Nov. 2003