V Congreso Latinoamericano de Ingeniería Biomédica (CLAIB2011)

Avaliação da SNR de ecos ultrassônicos gerados por pulso codificado e pulso convencional: um estudo comparativo
Tavares Costa Eduardo, de Moraes Machado Tiago

##manager.scheduler.building##: Palacio de Convenciones de La Habana
##manager.scheduler.room##: Sala 8
Fecha: 2011-05-20 11:45  – 12:00
Última modificación: 2011-04-28 10:36

Resumen


In this work we have made a comparative study of backscattering of ultrasound conventional and chirp codified pulses. We simulate the interaction of these two different pulses with a computational phantom constructed with variable amplitude and phase scatterers following a Gamma distribution. We use the signal-to-noise ratio (SNR) metric of the backscattered signals from both coded excitation pulse (CEP) and conventional pulse (CP) for various scenarios. The computational phantoms were created with regular and variable scaterers spacing as well as variation of their amplitude and phase with different transducers. Simulations were performed taking A-mode lines with simulated transducers operating in three frequencies: 2.25 MHz, 5.0 MHz and 7.5 MHz. The duration of the excitation CEP was 18μs and for each central frequency the extended transducers bandwidth was 3.7, 2.0 and 1.2 MHz respectively. The pulse compression was performed using matched (MF) and mismatched (MMF) filters. The results for different transducers and phantoms are in accordance to the literature and have given an improve of the SNR for coded pulse above 20 dB (in average) over conventional pulse excitation showing the possibility of increasing use of CEP for medical ultrasound imaging.