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: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=754476
• 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许多疾病的诊断，超声成像的分辨率由多种因素决定，包括换能器设计和操作频率。通常采用元件换能器，导致两个主要限制：1）穿透深度受到传播介质中超声波的大衰减以及与高频界面相关的像差和混响的限制， 2）与大量换能器元件相关的信号处理的复杂性仍然限制了给定图像质量可实现的帧速率，到目前为止，大部分工作都集中在成像算法或换能器设计的独特组合上。支持技术将在超声成像的穿透深度和帧速率方面取得重大突破：1) 成像算法 Excitelet，它利用低频超声并固有地考虑全波传播路径的详细模型，2) 压缩传感算法，它开发编码传播路径的多样性，以及 3) 增材制造技术，可在超材料内编码波传播路径 该项目的目标是创建具有少量元件的新一代稀疏超声换能器阵列，以降低信号处理复杂性。和更高的帧速率，并在低频下工作以提高穿透深度，因此打破了现有方法，该阵列将用于介质的超声成像，介质可以是工程材料或生物组织，横向分辨率低至1/30。长度寻求大穿透深度和 1-10 kHz 的帧速率。该研究计划阐明了三个平行但相关的研究主旨：1）使用超声换能器进行压缩传感，其中波的类型和频率将是。用于丰富信息编码，2) 稀疏换能器阵列的优化，其中优化过程中将考虑 Excitelet，以及 3) 超声探头制造中的超材料，其中增材制造技术将用于制造在材料测试中，这项工作将有助于更好地表征先进材料中的损伤前兆，例如复合结构（微裂纹、空隙、微屈曲、局部纤维断裂或局部）。在医学诊断中，这项工作将有助于满足对快速成像帧速率和近场和远场更好的分辨率的迫切需求，以避免引导程序中周围器官的风险。延长穿透深度以适应导致肥胖人口比例不断增加。