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:
Jan. 18, 2011
Filed:
May. 23, 2007
Shutong Zhou, Lansdale, PA (US);
Richard A. Meier, Abington, PA (US);
Shutong Zhou, Lansdale, PA (US);
Richard A. Meier, Abington, PA (US);
General Instrument Corporation, Horsham, PA (US);
Abstract
This anti clipping circuit is for a laser transmitter used to transmit sub-carrier multiplexed signals for CATV applications. The circuit design is based on actual clipping measurements showing the specific time and duration of the clipping events is random. The individual clipping pulses interval is fixed, every 4 us. A PHEMT peak detection circuit is used in conjunction with a missing pulse detector/timer to catch all the clipping events. Thus the laser bias current is adjusted automatically at the specific time of the clipping event and for the duration of all the clipping pulses in the event. The controlled increase and decrease of the lasers bias current is DC coupled back into the normal DC bias path via a diode. This gives the anti clipping circuit noise isolation when there are no clipping events and avoids laser clipping during the laser current recovery time as when using an AC coupling scheme.