| | |
Summary: GENERALIZED BROADBAND BEAMFORMING USING A MODAL DECOMPOSITION
Michael I. Y. Williams, Thushara D. Abhayapala, and Rodney A. Kennedy
Wireless Signal Processing Program, National ICT Australia,
and Department of Information Engineering, The Australian National University
{michael.williams, thushara.abhayapala, rodney.kennedy}@anu.edu.au
ABSTRACT
We propose a new broadband beamformer design technique which
produces an optimal beampattern for any set of samples in space
and time. The modal subspace decomposition (MSD) technique is
based on projecting a desired pattern into the subspace of patterns
achievable by a particular set of space-time sampling positions. This
projection is the optimal achievable pattern, in the sense that it mini-
mizes the mean-squared error (MSE) between the desired and actual
patterns. The main advantage of the technique is versatility as it
can produce optimal beamformers for both sparse and dense arrays,
non-uniform and asynchronous time sampling, and dynamic arrays
where sensors can move throughout space. It can also be applied to
any beampattern type, including frequency-invariant and spot pattern
design.
1. INTRODUCTION
|
