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. 11, 2004
Filed:
May. 24, 2002
Christopher D. Holdenried, Calgary, CA;
James W. Haslett, Calgary, CA;
John G. McRory, Calgary, CA;
Robert J. Davies, Calgary, CA;
Telecommunications Research Laboratories, Edmonton, CA;
Abstract
A parallel-summation logarithmic amplifier is described that uses a novel topology of cascaded and parallel amplifiers to achieve extremely high bandwidth. Included in the topology is a unique delay matching scheme for logarithmic amplifiers that is amenable to fabrication in integrated circuit form. The result is flat group delay over broad frequency ranges and different power levels. The resulting log amplifier is suitable for radar applications and for use in high data rate fiber-optic networks. Also described is a unique design process that yields a set of amplifier gains that closely approximate a logarithm. Also described is the novel idea of using a parallel feedback amplifier (PFA) in piecewise-approximate logarithmic amplifiers. This innovation allows for the design of broadband amplifiers with significantly different gains and similar phase characteristics, which is extremely useful when designing high-frequency logarithmic amplifiers.