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:
Jul. 12, 1994
Filed:
Jul. 31, 1992
Noriyuki Fujita, Tokyo, JP;
Masahiko Tanaka, Tokyo, JP;
NEC Corporation, , JP;
Abstract
A linear compensating circuit comprises a first level detection circuit for detecting the level of an input signal to an amplifier, a second level detection circuit for detecting the level of an output signal from the amplifier, an amplitude compensating circuit for controlling the amplitude of the input signal in accordance with the difference between the signal level detected by the first detection circuit and the signal level detected by the second level detection circuit for improving the linearity of an input-output characteristic of the amplifier, and a phase compensating circuit for controlling the phase of the input signal in accordance with the signal level detected by the second detection circuit. The linear compensating circuit compensates for both amplitude and phase and, as a result, the degradation of phase characteristic caused by amplitude compensation can be prevented, resulting in a reduction in the distortion of the output signal of the amplifier even when it is being operated in the vicinity of the saturation range. This linear compensating circuit is effective when applied to a power amplifier, particularly to a high frequency power amplifier.