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:
Apr. 25, 2017
Filed:
Mar. 06, 2013
Pgs Geophysical As, Lysaker, NO;
PGS Geophysical AS, Oslo, NO;
Abstract
A method and apparatus for generating an electromagnetic (EM) field from a sub-sea source is disclosed. In one embodiment, a sub-sea source includes a step-down transformer coupled to receive a sinusoidal source wave via a tow cable, and is further coupled to output a sinusoidal wave to a silicon-controlled rectifier (SCR) circuit. A control circuit coupled to the SCR circuit is configured to selectively activate various ones of the SCRs therein in order to control a portion of the sinusoidal wave that is rectified. The output current provided by the SCR is determined by the portion of the sinusoidal wave that is rectified thereby. The output current is provided to electrodes coupled to the sub-sea source, and the output current is passed therebetween. The strength of the EM field is based on the output current.