A Robust Steered Response Power Localization Method for Wireless Acoustic Sensor Networks in an Outdoor Environment

Area of Science:

• Acoustics
• Signal Processing
• Wireless Sensor Networks

Background:

• Outdoor acoustic source localization is crucial for wireless sensor networks.
• Existing steered response power (SRP) methods struggle with time delay uncertainty and coarse spatial grids.

Purpose of the Study:

• To propose a modified SRP-based method for robust outdoor acoustic source localization.
• To enhance localization accuracy in the presence of steering time delay uncertainty and coarser spatial grids.

Main Methods:

• Derivation of a sufficient condition for robust on-grid source localization using generalized cross-correlation (GCC) waveform functions.
• Development of a GCC refinement procedure using complex wavelet functions for band-pass GCCs.
• Filtering and averaging GCC envelopes to create an equivalent GCC matching the derived sufficient condition.

Main Results:

• The proposed SRP method effectively suppresses disturbances from grid distance and uncertain steering time delays.
• Simulation results and field experiments validate the enhanced localization robustness.
• The method demonstrates superior performance compared to existing SRP-based techniques.

Conclusions:

• The modified SRP-based method significantly improves the robustness of outdoor acoustic source localization.
• The GCC refinement procedure is key to achieving accurate localization under challenging conditions.
• This work offers a valuable advancement for acoustic sensing in wireless sensor networks.