Time-delay alignment technique for a randomly distributed sensor array

A simple algorithm that aligns signals of different arrival times on a randomly distributed sensor array is presented. For each sensor, the new algorithm makes use of the array combined output except for self-signal as reference, and the compensative delay value is determined with the reference to improve the performance of time-delay estimator. The theoretical convergence characteristics and the relative implementations in practice are also analysed. Furthermore, the study adopts time-delay estimator with cross-correlation plus Lagrange interpolation in common use to verify the validity and the performance of the proposed algorithm. Simulation results show that the algorithm achieves a substantial performance improvement over the conventional estimator with a single fixed reference owing to optimal usage of the mutual information between the sensors, especially at low signal-to-noise ratio (SNR) values.