Coded excitation primarily improves imaging by what mechanism?

Coded excitation primarily improves imaging by what mechanism?

• A. Increasing transmit power results in deeper imaging but worsens resolution
• B. Coded excitation increases the signal-to-noise ratio through pulse compression, enabling deeper imaging without lowering frame rate
• C. Coded excitation decreases penetration depth
• D. Coded excitation increases pulse repetition frequency

Answer: (B)

Coded excitation improves ultrasound imaging by sending a longer encoded pulse and then applying pulse compression at the receiver to recover a sharp, high-energy response. The encoded waveform spreads energy over time, which would lower SNR if listened to directly, but the matched-filter compression concentrates that energy back into time, producing a much higher signal-to-noise ratio. This boost in SNR allows echoes from deeper tissue to be detected more clearly, enabling deeper imaging without sacrificing frame rate because the system preserves the effective timing and resolution once the data are compressed. In short, it’s the combination of delivering more energy through encoding and recovering it with pulse compression that raises SNR and penetration while keeping frame rate.

Coded excitation improves ultrasound imaging by sending a longer encoded pulse and then applying pulse compression at the receiver to recover a sharp, high-energy response. The encoded waveform spreads energy over time, which would lower SNR if listened to directly, but the matched-filter compression concentrates that energy back into time, producing a much higher signal-to-noise ratio. This boost in SNR allows echoes from deeper tissue to be detected more clearly, enabling deeper imaging without sacrificing frame rate because the system preserves the effective timing and resolution once the data are compressed. In short, it’s the combination of delivering more energy through encoding and recovering it with pulse compression that raises SNR and penetration while keeping frame rate.