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Grade of written test: Final grade: Grade of project: Signature: Technologies for Sensors and Clinical Instrumentation 3 September 2015 FAMILY NAME ……………………….… NAME ….…………………. MATR ………… PREFERENCE for ORAL: † 7 September (morning) † 8 September (morning) † 9 September (morning) † next calls Notes: - Answers are considered complete only if units of measurement are indicated. - Only answers on printed sheets are considered for evaluation. Q.1) (7 points) …/2 - 1.a) Define and provide the formulas for the lateral resolution and axial resolution of a ultrasonic phased-array. Describe the artefact related to the grating lobes. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. A 64-element phased-array ultrasound probe is tested on a phantom containing gel and four small (diameter less than 0.1 mm) echoic particles, placed as shown in figure (not in scale). The pulse comprises 5 cycles. Ultrasonic beam has a steering angle ranging from -45 to 45 degrees, with very small angular steps (<0.1°). Ultrasonic focus is 3 cm depth. The pitch ݌is 1 mm. …/3 - 1.b) Assume that the probe operates at 1.5 MHz. By computing lateral and…