Ultrasound Image Improvement by Code Bit Elongation

Ihor Trots1, Andrzej Nowicki1, and Michiel Postema 2, 3, 4


1 Institute of Fundamental Technological Research of the Polish Academy of Sciences, Warsaw, Poland

2 School of Electrical and Information Engineering, Chamber of Mines Building, University of the Witwatersrand, Johannesburg, South Africa

3 LE STUDIUM Loire Valley Institute for Advanced Studies, 1 Rue Dupanloup, 45000, Orléans, France

4 Inserm Research Unit U1253: iBrain, Faculté de Médecine, Université de Tours, 10 Boulevard Tonnellé, 37032, Tours, France



This paper analyses the influence of the transducer bandwidth on the compression and the axial resolution of an ultrasound image. The distortion of an electrical signal visible in the final image is a major problem in ultrasonography. To solve this problem, the bit length in Golay-complementary sequences was elongated, narrowing the fractional bandwidth of the coded sequences. Therefore, more energy of the burst signal could be transferred through the ultrasound transducer. The experimental results obtained for transmission of the complementary Golay-coded sequences with two different bit lengths – one-cycle and two-cycles – have been compared, and the efficiency of the pulse compression and its influence on the axial resolution for two fractional bandwidths have been discussed. The results are presented for two transducers having a fractional bandwidth of 25% and 80% and operating at a 6-MHz frequency. The results obtained show that the elongation of the Golay single bit length (doubled in our case) compensate for the limited transducer bandwidth. 2D ultrasound images of a tissue-mimicking phantom are presented and demonstrate the benefits of the use of two-cycle bit length.


Coded excitation
Golay sequences
Synthetic aperture method
Transducer bandwidth
Ultrasound imaging.
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