Plane Wave Correlation Point Coherent Adaptive Beamforming Imaging Method

Abstract

The invention provides a coherent self-adaptive beam forming imaging method under the action of plane wave correlated points. The coherent self-adaptive beam forming imaging method under the action ofthe plane wave correlated points comprises the steps of 1) determining number and positions of the correlated points; 2) carrying out delay processing on sampling data; 3) estimating a covariance matrix, corresponding to two plane waves with reverse phases, of each correlated point according to the delay processing; 4) by combining a coherent coefficient and using a covariance matrix estimation result obtained in the step 3) to calculate a covariance matrix of each correlated point; 5) carrying out self-adaptive beam forming on the covariance matrix obtained in the step 4), and superposing beam forming value of each correlated point corresponding to a same sampling point in the sampling data; and 6) outputting the superposition result of the beam forming value of the correlated point of each sampling point in the form of a matrix. The coherent self-adaptive beam forming imaging method under the action of the plane wave correlated points, provided by the invention, has the advantages that the effect of an ultrasonic wave on a target sampling point at the correlated point is reflected by using coherent time delay; diagnostic information in the data cannot be increased when the coherent self-adaptive beam forming imaging method under the action of the plane wave correlated points is combined with single-angle or multi-angle plane wave self-adaptive beam forming; and therefore, the imaging contrast and resolution ratio are increased.

Description

technical field [0001] The invention belongs to the technical field of ultrasonic detection and ultrasonic imaging, and relates to an ultrasonic imaging algorithm, in particular to a single-angle or composite multi-angle coherent beam synthesis imaging method under the influence of relevant points. Background technique [0002] Ultrasound imaging is to scan the human body with ultrasonic sound beams, and obtain images of various organs by receiving and processing reflected signals. Ultrasound imaging can image many tissues and organs. At present, ultrasound mainly uses transcranial Doppler technology for intracranial monitoring. However, the development of intracranial angiographic imaging technology provides a more accurate method for intracranial monitoring. Vascular imaging of blood vessels overcomes many of the shortcomings of transcranial Doppler detection, but due to the obstruction of the skull, ultrasound imaging of intracranial tissues and vessels is still in the de...

AI Technical Summary

Problems solved by technology

When the covariance matrix is ​​inverted at a low number of snapshots, the small eigenvalue perturbation obviously causes the side lobe of the beam response to increase and the main lobe to be distorted

At the same time, since the covariance matrix estimation including the desired signal is used in practical applications, in the case of high signal-to-noise ratio and low number of snapshots, there is obvious coherence between the desired signal and noise interference

This greatly affects the performance of the MVDR algorithm

Coupled with the well-known scarcity of covariance matrix estimation samples, this degrades beamformer performance and degrades image quality

In particular, the signal-to-noise ratio and contrast are not ideal when the MVDR algorithm performs beamforming on a point where the low-echo signal is far from the central scan line

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