30 MHz medical imaging arrays incorporating 2-2 composites

Methods for fabricating and modeling high frequency 2-2 composites and arrays are presented. The composites are suitable for arrays and small aperture single element devices. Coupling coefficients above 0.65 and lateral mode frequencies near 60 MHz have been achieved. Two prototype 4 element 30 MHz linear arrays were designed and built using this composite. Backing and matching layers were fabricated and characterized while coaxial cable was used to electrically tune each element and broaden bandwidth. The measured properties of passive and active components were used to analyze the design in a time-domain finite element analysis program. Agreement between experiment and theory was excellent.