Flight parameter estimation using time delay and intersensor multipath delay measurements from a small aperture...

Area of Science:

• Acoustics
• Signal Processing
• Aerospace Engineering

Background:

• Ground-based acoustic sensor arrays traditionally estimate aircraft flight parameters using direct signal time-of-arrival measurements.
• Estimating precise flight parameters, especially with small sensor apertures, presents challenges due to limited spatial or temporal data.

Purpose of the Study:

• To investigate the use of intersensor multipath delay measurements to enhance the precision of aircraft flight parameter estimation.
• To determine if multipath delay data can improve estimates for small aperture arrays without increasing sensor spacing or observation time.

Main Methods:

• Formulating a flight parameter estimation algorithm incorporating intersensor multipath delay.
• Defining intersensor multipath delay as the differential time of arrival (DTOA) between a direct path signal at one sensor and a ground-reflected path signal at another.
• Performing a simplified Cramer-Rao lower bound error analysis to quantify precision improvements.

Main Results:

• Intersensor multipath delay measurements, when combined with standard time delay data, significantly reduce the standard deviations in flight parameter estimates.
• The proposed method demonstrates effectiveness for small aperture arrays.
• Validation was achieved using both simulated and real-world acoustic data.

Conclusions:

• Intersensor multipath delay is a valuable data source for improving acoustic-based aircraft flight parameter estimation.
• This technique offers a method to enhance precision for compact sensor arrays, overcoming limitations of traditional approaches.
• The findings support the practical application of multipath delay analysis in aerospace acoustics and surveillance.