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:
Jun. 14, 2011
Filed:
Dec. 19, 2007
Tomoo Murata, Fussa, JP;
Tomoo Murata, Fussa, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
When an optical signal that is a wide dynamic range and different in level depending on burst signals is input as in a GPON system, a preamplifier can stably control the gain within a short preamble. The gain changeover of the preamplifier is controlled by the aid of timing information that is extracted from a data signal as data count number, to change over the gain at a high speed and with high precision. A level detector, a preamble recovery, a counter, and a control circuit are disposed within the preamplifier in addition to a TIA main body. In order to suppress the band deterioration or the phase margin reduction which are attributable to the gain changeover, there is provided a bias terminal for conducting a current injection and a current drawing with respect to the signal amplification transistor of the TIA main body.