Fjield T, Hynynen K
Brigham and Women's Hospital, Boston, MA 02115, USA.
IEEE Trans Biomed Eng. 2000 Jan;47(1):139-41. doi: 10.1109/10.817630.
Phased-array technology offers an incredible advantage to therapeutic ultrasound due to the ability to electronically steer foci, create multiple foci, or to create an enlarged focal region by using phase cancellation. However, to take advantage of this flexibility, the phased-arrays generally consist of many elements. Each of these elements requires its own radio-frequency generator with independent amplitude and phase control, resulting in a large, complex, and expensive driving system. A method is presented here where in certain cases the number of amplifier channels can be reduced to a fraction of the number of transducer elements, thereby simplifying the driving system and reducing the overall system complexity and cost, by using isolation transformers to produce 180 degrees phase shifts.
相控阵技术为治疗性超声带来了巨大优势，因为它能够通过电子方式控制焦点、产生多个焦点，或者利用相位抵消来创建扩大的聚焦区域。然而，为了利用这种灵活性，相控阵通常由许多元件组成。这些元件中的每一个都需要其自身具有独立幅度和相位控制的射频发生器，从而导致驱动系统庞大、复杂且昂贵。本文提出了一种方法，在某些情况下，通过使用隔离变压器产生180度的相位偏移，放大器通道的数量可以减少到换能器元件数量的一小部分，从而简化驱动系统并降低整体系统的复杂性和成本。
