A linear F.M. ultrasonic pulse compression system suitable for flaw detection has been economically implemented by using an ultrasonic delay line. The operating system has a time bandwidth product of 84 and sidelobe levels below — 25 dB. Results relating to the system detection and resolution capabilities are presented.
Get full access to this article
View all access options for this article.
References
1.
KrautkrämerJ.KrautkrämerH., Ultrasonic Testing of Materials, George Allen and Unwin Ltd., London, (1969).
2.
HeuterT. F.BoltR. H., Sonics, Wiley & Sons, New York, (1955).
3.
CookC. E., ‘Pulse compression — key to more efficient radar transmission’, Proc. I.R.E., 48, pp. 310–316, (March, 1960).
4.
KlauderJ. R.PriceA. C.DarlingtonS.AlbersheimW. J., ‘The theory and design of 'chirp radars’, B.S.T.J., 39, pp. 745–808, (July, 1960).
5.
TurinG. L., ‘An introduction to matched filters’, I.R.E. Trans. Information Theory, pp. 311–329, (June, 1960).
6.
GaborD., ‘Theory of communication’, Proc. I.E.E., Part III, pp. 429–457, (1946).
7.
RampH. O.WingroveE. R., ‘Principles of pulse compression’, I.R.E. Trans. Military Electronics, pp. 109–116, (April, 1961).
8.
MeekerT. R., ‘Dispersive ultrasonic delay line using the first longitudinal mode in a strip’, I.R.E. Trans. Ultrasonic Engineering, UE-7, pp. 53–58, (June, 1960).
9.
BrandonP. S., ‘The spectra of linear and non-linear F.M. used in pulse compression, and the effects on the resultant compressed pulse’, Marconi Review, XXXVI, No. 189, pp. 69–92, Second Quarter, (1973).
10.
TemesC. L., ‘Sidelobe suppression in a range-channel pulse compression radar’, I.R.E. Trans. Military Electronics, MIL 4–6, pp. 162–169, (April, 1962).
11.
WheelerH. A., ‘The interpretation of amplitude and phase distortion in terms of paired echoes’, Proc. I.R.E., 27, pp. 359–385, (June, 1939).
