Patent ID: 11885917
Assignee: SURF TECHNOLOGY AS
Field: Measurement (Instruments)
Classification: CPC G  A | IPC A  G

Claim 0:
1. A method for estimation and imaging of propagation and scattering parameters in an object, comprising:
transmitting at least two pulse complexes composed of an overlapping high frequency (HF) and a low frequency (LF) pulse along at least one LF and HF transmit beam axis, where said HF pulse propagates close to the crest or trough of the LF pulse, and where one or both of the amplitude and polarity of the LF pulse varies between the at least two transmitted pulse complexes, where the amplitude of the LF pulse can be zero for a pulse complex and the amplitude of the LF pulse for at least one pulse complex of said at least two transmitted pulse complexes is non-zero, and
directing at least one HF receive cross-beam to cross said at least one HF transmit beam axis at a cross-angle to form cross-beam observation cells by overlap between each of said at least one HF receive cross-beam and each of said at least one HF transmit beam, and
recording at least two HF cross-beam receive signals scattered from object structures in each cross-beam observation cell from said at least two transmitted pulse complexes with different LF pulses, and
selecting the magnitude of said cross-angle to reduce multiple scattering noise in said HF cross-beam receive signals to produce adequately robust further processing of the HF cross-beam receive signals, and
processing said HF cross-beam receive signals for each said at least one HF receive cross-beams to provide at least one of
i) an estimated nonlinear propagation delay (NPD), and
ii) an estimated nonlinear pulse form distortion (PFD),
of the transmitted HF pulse at image points along said at least one HF transmit beam axis where said at least one HF transmit beam axis and said at least one HF receive cross-beam axis have shortest distance within each of said cross-beam observation cells, and
using said estimated PFD and/or NPD for further processing, and
gating out an interval of each said signals to form cross-beam receive signals scattered from cross-beam observation cells at different depths along each transmit beams to produce adequately robust further processing of the HF cross-beam receive signal.