The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 10, 2011
Filed:
Mar. 25, 2009
Stephen Maslen, Somerset, GB;
Stephen Maslen, Somerset, GB;
Radiodetection Limited, Bristol, GB;
Abstract
The present invention provides a method of time domain reflectometry including transmitting a test signal along a cable under test from one end and sensing and recording a reflected signal from the cable at that end, using the recorded, reflected signal to estimate the distance, Ldist, from the one end to a discontinuity on the cable, separating a test signal component from the remainder, Vr, of the reflected signal; estimating the impedance, Zfault, of the discontinuity from known, predetermined values of the characteristic impedance, Zline, and of the characteristic gain, T, of a reference cable, and from the said separated test signal and reflected signal components, calculating the estimation error as a difference between the model reflection signal, Vrmod, expected of the cable under test based on the characteristic impedance and characteristic gain and the estimated impedance, Zfault and distance, Ldist, and the actual reflection signal Vr, choosing new estimated values of Ldist and Zfault in accordance with a predetermined algorithm such as to approach optimal values, repeating the aforesaid step of calculating the estimation error until a predetermined condition has been satisfied, and outputting the values of Ldist and Zfault that gave the least error.