Coded excitation in 3D ultrasound imaging with a lensed row-column array

With fewer electrical connections and larger apertures, row-column arrays can be a potential alternative to matrix arrays in high-resolution volumetric imaging. However, these probes have a rectangular field of view (FOV), which is equal to their footprint. It is possible to expand FOV with a diverging lens, but the lens causes wave attenuation, which reduces the signal-to-noise ratio (SNR) and probe penetration depth. This paper aims to demonstrate that a large FOV can be achieved in 3D ultrasound imaging using a lens and coded excitation (CE) without negatively impacting the SNR and penetration depth. The proposed method was evaluated using a chirp signal with a center frequency of 6 MHz, a bandwidth of 4 MHz, and a duration of 5 µs. With the CE signal, the SNR increased by approximately 10 dB compared to sinusoidal excitation.