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:
Nov. 17, 1998
Filed:
Aug. 28, 1997
Mikio Fukushi, Tokyo, JP;
NEC Corporation, , JP;
Abstract
In a modulating system, a converting unit generates first and second quadrature signals based on a transmission data signal in synchronous with a transmission clock signal. First and second filters perform band limitation to the first and second quadrature signals to generate first and second band-limited quadrature signals. An oscillator generates a sine wave signal and a phase shifter phase-shifts the sine wave signal from the oscillator to generate first and second phase-shifted sine wave signals. A phase difference between them is .pi./2, and the first phased-shifted sine wave signal precedes the second phased-shifted sine wave signal in the phase. First and second multipliers multiply the first and second phase-shifted sine wave signals by the first and second band-limited quadrature signals to generate first and second multiplied signals, respectively. An adder synthesizes the first and second multiplied signals to generate an synthesis signal. Then, a limiter for limiting an amplitude of the synthesis signal to a predetermined level.