The Enhancement of 3 MHz Ultrasonic Echo Signal for Conversion Curve Development for Acoustic Impedance Estimation by Using Wavelet Transform

Abstract

Ultrasonic technology has already been applied for many applications. Most of them are mainly used for object measurement. Some techniques have been widely applied to particular measurement by utilizing a very specific component. In this research, the previous technique to develop a conversion curve to obtain the acoustic impedance of the target is adopted. Then, a 3 MHz concave shaped ultrasonic transducer for measuring liquids is proposed and a confirmation is needed to confirm if the system is correct. Therefore, several saline solutions with some known properties are used. A low voltage of 10 Volt pulse is sent to trigger the transducer. The ultrasonic wave is transmitted through the multilayered mediums, which is pure water, clear acrylic, and the target. The echo from the interface between the acrylic and the target is then received by the same transducer. Some parameters such as peak and Root Mean Square (RMS) are used to develop the conversion curve. A peak detection and comparison between the original echo and the processed one by using Wavelet transform is performed. Some analysis of the echo signal by using multiresolution and timefrequency analysis are also proposed. The result obtained from the measurement is then compared to the theoretical calculation. Based on the result, in terms of developing the conversion curve, only the RMS value of the Undecimated Wavelet Transform (UWT) which has the closest trend to the result of the calculation, with the mean percentage error of 0.65512%, which is the smallest value among all parameters.

Prototipe Deteksi PEN dalam Tubuh Menggunakan B-Mode Ultrasonic Scanning

“…Pengujian transducer ini bertujuan untuk memastikan bahwa transducer yang digunakan dapat bekerja dengan baik. Pengujian dilakukan dengan melakukan scanning dengan objek air yang diletakkan dalam wadah akrilik seperti yang telah dilakukan pada oleh literatur [15].…”