Which method enables electronic steering by delaying signals across the array while transmitting all elements together?

• A. Rectification
• B. Phased array transducers
• C. Dynamic aperture
• D. Apodization

Answer: (B)

Electronic steering is achieved through beamforming with a phased array. By applying precise time delays to each element as they fire together, the emitted wavefront is tilted so that constructive interference occurs in a chosen direction, steering the beam without moving the probe. Adjusting these delays can also focus the beam at a specific point, but the core idea is that all elements transmit simultaneously with controlled delays to direct the beam electronically. The other terms describe different aspects of ultrasound imaging: rectification is just a signal-processing step to recover the envelope, dynamic aperture involves changing how many elements participate to optimize resolution at depth, and apodization weights element excitations to reduce sidelobes—none of which define the act of steering by delaying all elements together.