A time-frequency approach to blind deconvolution in multipath underwater channels
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Citations
Blind deconvolution for robust signal estimation and approximate source localization.
Broadband sparse-array blind deconvolution using frequency-difference beamforming
Blind separation of underwater acoustic signals
Feasibility of passive oceanic acoustic tomography: a Cramer Rao bounds approach
A Noise-Robust Method with Smoothed 1/2 Regularization for Sparse Moving-Source Mapping
References
On the quantum correction for thermodynamic equilibrium
Time-Frequency Analysis
Quantum mechanics as a statistical theory
Time-Frequency Analysis
Linear and quadratic time-frequency signal representations
Related Papers (5)
Frequently Asked Questions (11)
Q2. What is the main method used to obtain the source signal estimate?
The basis method[3] was employed, where a linear combination of the basis functions ek(t) was used to obtain the final source signal estimate such asŝ(t) = Nb∑ k=1 αkek(t).
Q3. What is the inverse Fourier transform operator?
An also important TFD is the signal-dependent distribution radially Gaussian kernel distribution (RGK)[2]RGKx(t, f) = IFT2 [ΦRGK,x(ν, τ)AFx (ν, τ)] , (2)where ΦRGK,x(t, f), the kernel of the distribution, is adapted to the signal to be analyzed, AFx (ν, τ) stands for the ambiguity function of x(t), and IFT2[·] designates the bi-dimensional (2D) inverse Fourier transform operator.
Q4. What is the IF of a non-linear frequency modulated source signal?
for a non-linear frequency modulation source signal, there are always ITs in its auto-WV, what may require a smaller value for the kernel volume of RGKr(t, f), if some ITs of that auto-WV have greater amplitude than the signal terms.
Q5. Why was the IF estimation based on the IF of s(t)?
Due to the typical presence of one or a few strong arrivals in h(t), the IF estimation consisted of the global maximization with respect to t, of the signal-dependent distribution RGK of the received signal, RGKr(t, f):[t, f̂i(t)] = {(t, f) : t=arg max t RGKr(t, f), f∈B}.
Q6. What is the frequency of the band limitation signal?
The band limitation signal cons-traint is reflected not only in the increased signal duration, but also in an increase of the IF range, since the limitation to [0, fs/2] gave the freedom to the estimate’s IF to extend in the whole [0, 850]
Q7. What is the quality of the channel estimate?
One normalized measure of the quality can be given asρa = 1 − ||a − â||2 ; ρτ = 1 − ||τ − τ̂ || 2 , (7)where the vectors must first be unitarily normalized.
Q8. What is the IF value of the source signature?
Considering the multi-component structure of the noiseless received signal, source signature estimation was performed by application of the basis method, whose output is given by (3), and whose model function was defined by the product of WVr(t, f) by a 2D function, centered on the IF estimate of s(t).
Q9. What is the purpose of this paper?
This paper aims to give an approach to solve the problem of blind deconvolution in ocean acoustics, i.e., obtaining at once estimates of the emitted signal and the medium impulse response (IR) representative of its physical properties.
Q10. What is the main problem in acoustics?
One of these areas is ocean acoustics, where a fundamental problem is the passive characterization of acoustic transients and the ocean environment.
Q11. What are the amplitudes of the arrivals?
The amplitudes am and time-delays τm of the arrivals are the channel parameters to estimate, grouped into the vectors a and τ , respectively.