Narrowband Ultrasonic Phased Array Control Using A Photonic Beamformer
Abbreviated Journal Title
ultrasound; phased arrays; photonics; acousto-optics; nematic liquid; crystals; beamforming; NONDESTRUCTIVE EVALUATION; TRANSDUCER; APPLICATOR; Acoustics; Radiology, Nuclear Medicine & Medical Imaging
A novel narrowband photonic beamformer for ultrasonic phased array control is proposed and demonstrated. The dual Bragg cell in-line optical design allows for the use of radio frequency Bragg cells for stable low frequency (DC-15 MHz) signal generation for driving ultrasonic arrays. Two tiny stamp size nematic liquid crystal devices provide the sites for signal phase (0-2 pi) and amplitude control. The proof-of-principle beamformer demonstrated 0-2 pi phase control and 55.8 dB gain control for a 10 MHz output signal that showed a carrier-to-noise ratio of 108 dB Hz(-1) at +100 kHz offset. Both continuous and pulsed mode beamformer operation are demonstrated. Features of the photonic beamformer include analog control, wide tuning range, fiber remoting, size/weight advantages, and low control power operation.
"Narrowband Ultrasonic Phased Array Control Using A Photonic Beamformer" (1996). Faculty Bibliography 1990s. 1738.