Title
Low-Complexity Addition or Removal of Sensors/Constraints in LCMV Beamformers
Abstract
We address the application of the linearly constrained minimum variance (LCMV) beamformer in sensor networks. In signal processing applications, it is common to have a redundancy in the number of nodes, fully covering the area of interest. Here we consider suboptimal LCMV beamformers utilizing only a subset of the available sensors for signal enhancement applications. Multiple desired and interfering sources scenarios in multipath environments are considered. We assume that an oracle entity determines the group of sensors participating in the spatial filtering, denoted as the active sensors. The oracle is also responsible for updating the constraints set according to either sensors or sources activity or dynamics. Any update of the active sensors or of the constraints set necessitates recalculation of the beamformer and increases the power consumption. As power consumption is a most valuable resource in sensor networks, it is important to derive efficient update schemes. In this paper, we derive procedures for adding or removing either an active sensor or a constraint from an existing LCMV beamformer. Closed-form, as well as generalized sidelobe canceller (GSC)-form implementations, are derived. These procedures use the previous beamformer to save calculations in the updating process. We analyze the computational burden of the proposed procedures and show that it is much lower than the computational burden of the straightforward calculation of their corresponding beamformers.
Year
DOI
Venue
2012
10.1109/TSP.2011.2177829
IEEE Transactions on Signal Processing
Keywords
Field
DocType
array signal processing,spatial filters,wireless sensor networks,GSC form implementation,active sensors,generalized sidelobe canceller,linearly-constrained minimum-variance beamformer,low-complexity sensor-constraint addition,low-complexity sensor-constraint removal,multipath environments,oracle entity,power consumption,sensor networks,signal enhancement application,signal processing applications,spatial filtering,suboptimal LCMV beamformers,Beamforming,GSC,LCMV
Multipath propagation,Beamforming,Signal processing,Mathematical optimization,Oracle,Bandwidth (signal processing),Redundancy (engineering),Wireless sensor network,Mathematics,Computational complexity theory
Journal
Volume
Issue
ISSN
60
3
1053-587X
Citations 
PageRank 
References 
5
0.43
12
Authors
3
Name
Order
Citations
PageRank
Markovich-Golan, S.150.43
Sharon Gannot21754130.51
Irun R. Cohen329621.62