Compressive sensing-based sparse transducers for ultrasound imaging

用于超声成像的基于压缩传感的稀疏换能器

• 批准号: RGPIN-2020-07053
• 负责人: Masson, Patrice
• 金额: $ 2.84万
• 依托单位: Université de Sherbrooke
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=718444
• 关键词: Compressive; sensing; based; sparse; transducers

Ultrasound imaging is used routinely for material testing and for the diagnosis of many diseases. The resolution of ultrasound imaging is determined by various factors, including transducer design and frequency of operation. To maximize resolution, high operating frequencies (> 1 MHz) and multi-element transducers are usually employed, leading to two major limitations: 1) the penetration depth is limited by the large attenuation of the ultrasonic waves in the propagating medium and by the aberration and reverberation associated with the interfaces at high frequencies, 2) the complexity of the signal processing associated with a large number of transducer elements still limits the achievable frame rate for a given image quality. Until now, most of the work conducted has focused on either imaging algorithms or transducers design. A unique combination of enabling technologies will allow a major breakthrough in the penetration depth and frame rate in ultrasound imaging: 1) the imaging algorithm Excitelet, which exploits lower frequency ultrasound and inherently considers a detailed model of the full wave propagation path, 2) compressive sensing algorithms, which exploit diversity in encoded propagation paths, and 3) additive manufacturing technologies, which enable encoding wave propagation paths within metamaterials. The objective of this program is to create a new generation of sparse ultrasound transducer arrays with a low number of elements, for lower signal processing complexity and higher frame rate, and working at low frequency for improved penetration depth, therefore breaking with existing approaches. The arrays will be used for ultrasound imaging of media which can be either engineering materials or biological tissues. Lateral resolution down to 1/30 of the wavelength is sought at large penetration depth and at a frame rate in the order of 1-10 kHz. This research program articulates along three research thrusts, parallel but related: 1) compressive sensing with ultrasound transducers, where the type of waves and frequencies will be used to enrich information encoding, 2) optimization of sparse transducer arrays, where Excitelet will be considered within the optimization process, and 3) metamaterials in ultrasound probe fabrication, where additive manufacturing techniques will be used to fabricate the metamaterials for encoding the information and other components of the probe. In material testing, this work will allow better characterization of damage precursor in advanced materials, such as composite structures (micro-cracks, voids, micro-buckling, local fiber breakage, or local fiber-matrix debonding). In medical diagnosis, this work will contribute to answer an urgent need for fast imaging frame rates and better resolution in both near- and far-field to avoid the risks in the surrounding organs in guided procedures, in addition to extended penetration depth in order to adapt to the increasing proportion of the obese population.

超声成像通常用于材料测试和诊断许多疾病。超声成像的分辨率取决于各种因素，包括换能器设计和操作频率。为了最大化分辨率，通常采用高工作频率（> 1 MHz）和多元素传感器，导致两个主要局限性：1）渗透深度受到传播介质中超声波的大量衰减的限制，并由异常衰减。与高频处的接口相关的回响，2）与大量传感器元素相关的信号处理的复杂性仍然限制给定图像质量的可实现的帧速率。到目前为止，进行的大多数工作都集中在成像算法或传感器设计上。启用技术的独特组合将允许超声成像中的穿透深度和帧速率取得重大突破：1）成像算法兴奋剂激素，它利用较低的频率超声，并固有地考虑了全波传播路径的详细模型，2）压缩路径2）传感算法，利用编码的传播路径中的多样性和3）增材制造技术，该技术可以在超材料内进行编码波传播路径。该程序的目的是创建新一代的稀疏超声传感器阵列，其元素数量较低，较低的信号处理复杂性和较高的帧速率，并以低频工作以改善渗透深度，因此使用现有方法破裂。该阵列将用于介质的超声成像，该培养基可以是工程材料或生物组织。在较大的穿透深度和以1-10 kHz的顺序下，寻求较低的波长的横向分辨率。该研究计划沿三个研究推力阐明，但相关但相关：1）用超声传感器进行压缩感测，其中波浪和频率的类型将用于丰富信息编码，2）优化稀疏传感器阵列的优化，在其中，将在其中考虑激发质的内部。优化过程和3）超声探针制造中的超材料，其中添加剂制造技术将用于制造超材料以编码探针的信息和其他组件。在材料测试中，这项工作将可以更好地表征高级材料中的损伤前体，例如复合结构（微裂缝，空隙，微弹性，局部纤维损坏或局部纤维 - 纤维 - 矩阵剥离）。在医学诊断中，这项工作将有助于应对快速成像框架速率的迫切需求，并在近场和远场上更好地分辨率，以避免在有指导过程中避免周围器官的风险适应肥胖人群的越来越多。