Authors:
Ihor Trots
;
Andrzej Nowicki
and
Marcin Lewandowski
Affiliation:
Institute of Fundamental Technological Research, Polish Academy of Sciences, Poland
Keyword(s):
Golay complementary sequences, Double pulse transmission, Dead zone.
Related
Ontology
Subjects/Areas/Topics:
Applications and Services
;
Biomedical Engineering
;
Biomedical Signal Processing
;
Computer Vision, Visualization and Computer Graphics
;
Medical Image Detection, Acquisition, Analysis and Processing
Abstract:
This study investigates a new composing method of double transmission of short coded sequences based on well-known Golay complementary codes, which allows to obtain the higher signal-to-noise ratio (SNR) and decrease dead zone area. The proposed method can potentially find application in small parts ultrasonography and play an important role in examination of superficial structures, e.g. in dermatology, ophthalmology, etc., where using longer coded sequences leads to increase of a dead zone and single pulse transmission of short sequences does not assure sufficient SNR.
This paper discusses the results obtained during the examination of four different length pairs of Golay coded sequences excited at 3.7 MHz: the single 64-bits pair of Golay sequences and combined sequences consisting of two 8, 16, and 32-bits Golay codes separated in time. The experimental results have shown that double pulse transmission allows to suppress considerably the noise level, the SNR increases by 5.7 dB i
n comparison with the single pulse transmission of Golay sequences of the same length. The presented results of this work demonstrate the advantage of double pulse transmission method which enhances SNR while maintaining the dead zone short.
(More)