Ultrasound Transducer Array Grating Lobe Mitigation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Ultrasound transducer arrays suffer from grating lobe artifacts due to the location of gating lobes within the imaging field, which are difficult to eliminate without compromising signal-to-noise characteristics or increasing the number of elements, leading to higher costs.
Innovation Solution
The solution involves configuring transducer elements with effective widths equal to or greater than the pitch by spatially or temporally interleaving them, allowing the grating lobes to fall outside the imaging field, thereby reducing artifacts. This is achieved through various geometries such as protruding elements, stair-case shapes, and electrical connections that effectively increase the element width beyond the pitch, and using synthetic aperture algorithms to combine data from different acquisitions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If the pitch is reduced to avoid large grating lobes, then grating lobe artifacts are reduced, but narrower elements have poorer signal-to-noise characteristics and greater impedance mismatch
Solution Approach 1:
The patent applies temporal interleaving to shift the problem from spatial domain to temporal domain. By acquiring data at different time points with different element subsets and combining them synthetically, the effective width is increased without physically narrowing elements, thus reducing grating lobes while preserving signal-to-noise ratio.
Solution Approach 2:
The patent changes the operational parameters by using synthetic aperture techniques where the effective element width is dynamically adjusted through data processing. This allows the system to achieve the benefits of wider elements (reduced grating lobes) without the physical constraints of actually using wider elements.
2Object-affected harmful factors
If narrower elements are used to reduce pitch, then grating lobes are reduced, but a greater number of elements are needed for a given array aperture, increasing cost
Solution Approach 1:
The patent introduces temporal dimension through interleaved acquisitions, allowing fewer physical elements to achieve the effective aperture of more elements. The synthetic aperture processing creates the equivalent effect of having more or wider elements without actually increasing the physical element count.
Solution Approach 2:
Each transducer element serves multiple functions across different time points and acquisition cycles. The same physical elements are reused in different configurations to synthesize the effect of a larger aperture, reducing the need for additional elements.
3Reliability
If wider elements are used, then signal-to-noise characteristics improve, but grating lobes fall within the imaging field causing artifacts
Solution Approach 1:
The patent divides the aperture into multiple subsets that are activated at different time points. By segmenting the element usage and combining results synthetically, the system achieves the signal-to-noise benefits of wider effective apertures while controlling grating lobe positions through the segmentation pattern.
Solution Approach 2:
The patent employs periodic interleaved acquisitions where different element subsets are activated in alternating time cycles. This periodic switching allows the system to accumulate data that effectively widens the aperture while the temporal separation prevents grating lobes from falling within the imaging field.
Data Source
Figure 1~2
Figure 3
Figure 4~5
AI summary
An imaging transducer (304) includes a plurality of transducer elements (404, 604, 704, 804) arranged with respect to each other in an array along an long axis (405) of the transducer (304), wherein an effective width (406) of a transducer element (404) of the transducer (304) is equal to or greater than a center - to - center distance (412) between adjacent transducer elements (404). A method includes acquiring data with an imaging transducer (304), wherein the transducer (304) includes a plurality of transducer elements ( 404, 604, 704, 804 ) arranged with respect to each other in an array along an long axis (405) of the transducer (304), wherein an effective width (406) of a transducer element (404) of the transducer (304) is equal to or greater than a center - to - center distance (412) between adjacent transducer elements (404).