5E-4 A Matrix Method for Modeling Electrical Crosstalk Applied to Ultrasonic Imaging Probes Using Micro-Miniature Ribbon Cable

Crosstalk is an important phenomenon that can negatively affect the performance of an ultrasound array coupled to an imaging system. This paper presents a means of using cable measurements to predict the effect of electrical crosstalk between the intended array element and neighboring elements, with the cable terminated by system electronics at the near end. The KLM model is used to predict the array operation, and directivity measurements for a 6.5 MHz array without a cable show a -6 dB angular response of 70 deg. The addition of a cable and its associated crosstalk causes the effective radiating aperture to become larger and the angular response less. The termination condition at the system end effects how the array and cable interact to produce crosstalk. The signal level measured for a miniature phased array and 1.5 m of ribbon cable with adjacent elements open at the system end was 2.1 dB higher than with adjacent elements grounded. Similarly, the acceptance angle was found to be only 45 degrees with adjacent elements open and 55 degrees with adjacents shorted. Comparisons of measurements for various combinations of array, cable, and system termination conditions against modeled equivalents show excellent agreement. Crosstalk effects on the quality of the formed beam are discussed