Should compression of coded waveforms be done before or after focusing?

Rasmus Bjerngaard; Joergen Arendt Jensen

doi:10.1117/12.462176

11 April 2002 Should compression of coded waveforms be done before or after focusing?

Rasmus Bjerngaard, Joergen Arendt Jensen

Proceedings Volume 4687, Medical Imaging 2002: Ultrasonic Imaging and Signal Processing; (2002) https://doi.org/10.1117/12.462176
Event: Medical Imaging 2002, 2002, San Diego, California, United States

Abstract

In medical ultrasound signal-to-noise ratio improvements of approximately 15-20 dB can be achieved by using coded waveforms. Exciting the transducer with an encoded waveform necessitates compression of the response which is computationally demanding. This paper investigates the possibility of reducing the workload without introducing errors. N_e - 1 compression filtrations (convolutions) can be saved by inverting the precedence of compression and beamforming (called post-compression), when N is the number of transducer elements. Post-compression with dynamic receive focusing will theoretically introduce errors. Simulations and measurements show that increasing the depth of the scatterers results in a decreased error. Transmit focus depth and the distance between focus points have a significant influence on the error. The size of the error is studied and a new scheme for correcting the error is proposed. The study is done by simulations in Field II and by measurements with our experimental scanner RASMUS. The measurements are done on a string phantom and in-vivo on the abdomen of a male volunteer.

Citation Download Citation

Rasmus Bjerngaard and Joergen Arendt Jensen "Should compression of coded waveforms be done before or after focusing?", Proc. SPIE 4687, Medical Imaging 2002: Ultrasonic Imaging and Signal Processing, (11 April 2002); https://doi.org/10.1117/12.462176

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available