Often in applications it is desired to remotely identify an object from its reflected signature. In active sonar the object is insonified by a transmitted waveform which may be broadband (modulated) or narrowband and the received pressure is processed to localize and identify the object. Identification usually requires a broadband transmitted waveform. In this paper the received pressure time series from spherical acoustic objects in motion that have been insonified by linear frequency modulated waveforms are used to identify the objects. Specifically, the unknown object's unknown Doppler using an unique property of the fourth- order spectrum is extracted and then its transfer function is extracted. The results for five spherical acoustic objects in motion are discussed. Three methods, deconvolution, matched filtering, and fourth-order spectrum deconvolution to extract the object's transfer function are compared.
[1]
Roger F. Dwyer,et al.
The fourth‐order cumulant spectrum of a filtered linear frequency‐modulated source in motion
,
1993
.
[2]
D. Brillinger.
The identification of a particular nonlinear time series system
,
1977
.
[3]
T.J. Ulrych,et al.
Phase estimation using the bispectrum
,
1984,
Proceedings of the IEEE.
[4]
J. Klauder,et al.
The theory and design of chirp radars
,
1960
.
[5]
M. Rosenblatt,et al.
Deconvolution and Estimation of Transfer Function Phase and Coefficients for NonGaussian Linear Processes.
,
1982
.