Patent US5329244A successfully refreshed from Google Patents.
← Back to Patent Explorer
US5329244A Expired / Lapsed US ⏱️ 0.0 years remaining

Linear compensating circuit

Assignee: NEC Corp
•
Filing: 1992-07-31
•
Granted: 1994-07-12
•
Expires: 2012-07-31
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

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.

Inventors

  • 👤 Noriyuki Fujita
  • 👤 Masahiko Tanaka

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 15:22
CPC Classifications
H; H03; H03G; H03G3/00; H03G3/20; H03G3/30; H03G3/3036; H03G3/3042; H03F; H03F1/00; H03F1/32; H03F1/3241; H03F1/3247; H03F1/3282; H03F1/3288

Claims Analysis

Total Claims: 23
Claim 1
Independent Claim 181 words
A linear compensating circuit for maintaining a linearity of an input-output characteristic of an amplifying means comprising: first level detection means for detecting a level of an input signal to be inputted to said amplifying means; second level detection means for detecting a level of an output signal to be outputted from said amplifying means; amplitude compensating means for controlling an amplitude of said input signal in accordance with a difference between a signal level detected by said first detection means and a signal level detected by said second detection means to improve said linearity of said input-output characteristic of said amplifying means; and phase compensating means for controlling a phase of said input signal in accordance with a level of an output signal detected by said second level detection means wherein at least one of said input and output signals is provided through a branching circuit, said branching circuit being effective for controlling said level of said input signal and said level of said output signal associated, respectively, with said first level detection means and said second level detection means.
Claim 2
Dependent Claim 181 words
A linear compensating circuit for maintaining a linearity of an input-output characteristic of an amplifying means comprising: first level detection means for detecting a level of an input signal to be inputted to said amplifying means; second level detection means for detecting a level of an output signal to be outputted from said amplifying means; amplitude compensating means for controlling an amplitude of said input signal in accordance with a difference between a signal level detected by said first detection means and a signal level detected by said second detection means to improve said linearity of said input-output characteristic of said amplifying means; and phase compensating means for controlling a phase of said input signal in accordance with a level of an output signal detected by said second level detection means wherein at least one of said input and output signals is provided through a branching circuit, said branching circuit being effective for controlling said level of said input signal and said level of said output signal associated, respectively, with said first level detection means and said second level detection means.
Claim 3
Dependent Claim 158 words
A linear compensating circuit for maintaining a linearity of an input-output characteristic of an amplifying means comprising: first level detection means for detecting a level of an input signal to be inputted to said amplifying means; second level detection means for detecting a level of an output signal to be outputted from said amplifying means; amplitude compensating means for controlling an amplitude of said input signal in accordance with a difference between a signal level detected by said first detection means and a signal level detected by said second detection means to improve said linearity of said input-output characteristic of said amplifying means; and phase compensating means for controlling a phase of said input signal in accordance with a level of an output signal detected by said second level detection means; and wherein said phase compensating means has a characteristic that cancels a phase change of said output signal induced by amplitude compensation of said amplitude compensating means.
Claim 4
Dependent Claim 158 words
A linear compensating circuit for maintaining a linearity of an input-output characteristic of an amplifying means comprising: first level detection means for detecting a level of an input signal to be inputted to said amplifying means; second level detection means for detecting a level of an output signal to be outputted from said amplifying means; amplitude compensating means for controlling an amplitude of said input signal in accordance with a difference between a signal level detected by said first detection means and a signal level detected by said second detection means to improve said linearity of said input-output characteristic of said amplifying means; and phase compensating means for controlling a phase of said input signal in accordance with a level of an output signal detected by said second level detection means; and wherein said phase compensating means has a characteristic that cancels a phase change of said output signal induced by amplitude compensation of said amplitude compensating means.
Claim 5
Dependent Claim 24 words
The linear compensating circuit as claimed in claim 1, wherein at least one of said first and second level detection means is a detector.
Claim 6
Dependent Claim 164 words
A linear compensating circuit for maintaining a linearity of an input-output characteristic of an amplifying means comprising: first level detection means for detecting a level of an input signal to be inputted to said amplifying means; second level detection means for detecting a level of an output signal to be outputted from said amplifying means; amplitude compensating means for controlling an amplitude of said input signal in accordance with a difference between a signal level detected by said first detection means and a signal level detected by said second detection means to improve said linearity of said input-output characteristic of said amplifying means; and phase compensating means for controlling a phase of said input signal in accordance with a level of an output signal detected by said second level detection means; wherein at least one of said input and output signals is provided through a branching circuit; and wherein said branching circuit has means for controlling the level of a signal to be provided.
Claim 7
Dependent Claim 164 words
A linear compensating circuit for maintaining a linearity of an input-output characteristic of an amplifying means comprising: first level detection means for detecting a level of an input signal to be inputted to said amplifying means; second level detection means for detecting a level of an output signal to be outputted from said amplifying means; amplitude compensating means for controlling an amplitude of said input signal in accordance with a difference between a signal level detected by said first detection means and a signal level detected by said second detection means to improve said linearity of said input-output characteristic of said amplifying means; and phase compensating means for controlling a phase of said input signal in accordance with a level of an output signal detected by said second level detection means; wherein at least one of said input and output signals is provided through a branching circuit; and wherein said branching circuit has means for controlling the level of a signal to be provided.
Claim 8
Dependent Claim 17 words
The linear compensating circuit as claimed in claim 1, wherein said amplifying means is a power amplifier.
Claim 9
Dependent Claim 146 words
An amplifier comprising: amplifier means; first level detection means for detecting a level of an input signal to be inputted to said amplifying means; second level detection means for detecting a level of an output signal to be inputted to said amplifying means; amplitude compensating means for controlling an amplitude of said input signal in accordance with a difference between a signal level detected by said first detection means and a signal level detected by said second detection means to improve a linearity of an input-output characteristic of said amplifying means; and phase compensating means for controlling a phase of said input signal in accordance with a level of an output signal detected by said second level detection means; and wherein said phase compensating means has a characteristic that cancels a phase change of said output signal induced by amplitude compensation of said amplitude compensating means.
Claim 10
Dependent Claim 146 words
An amplifier comprising: amplifier means; first level detection means for detecting a level of an input signal to be inputted to said amplifying means; second level detection means for detecting a level of an output signal to be inputted to said amplifying means; amplitude compensating means for controlling an amplitude of said input signal in accordance with a difference between a signal level detected by said first detection means and a signal level detected by said second detection means to improve a linearity of an input-output characteristic of said amplifying means; and phase compensating means for controlling a phase of said input signal in accordance with a level of an output signal detected by said second level detection means; and wherein said phase compensating means has a characteristic that cancels a phase change of said output signal induced by amplitude compensation of said amplitude compensating means.
Claim 11
Dependent Claim 22 words
The amplifier as claimed in claim 6, wherein at least one of said first and second level detection means is a detector.
Claim 12
Dependent Claim 23 words
The amplifier as claimed in claim 6, wherein at least one of said input and output signals is provided through a branching circuit.
Claim 13
Dependent Claim 153 words
An amplifier comprising: amplifier means; first level detection means for detecting a level of an input signal to be inputted to said amplifying means; second level detection means for detecting a level of an output signal to be inputted to said amplifying means; amplitude compensating means for controlling an amplitude of said input signal in accordance with a difference between a signal level detected by said first detection means and a signal level detected by said second detection means to improve a linearity of an input-output characteristic of said amplifying means; and phase compensating means for controlling a phase of said input signal in accordance with a level of an output signal detected by said second level detection means; and wherein at least one of said input and output signals is provided through a branching circuit and wherein said branching circuit includes means for controlling the level of a signal to be provided.
Claim 14
Dependent Claim 153 words
An amplifier comprising: amplifier means; first level detection means for detecting a level of an input signal to be inputted to said amplifying means; second level detection means for detecting a level of an output signal to be inputted to said amplifying means; amplitude compensating means for controlling an amplitude of said input signal in accordance with a difference between a signal level detected by said first detection means and a signal level detected by said second detection means to improve a linearity of an input-output characteristic of said amplifying means; and phase compensating means for controlling a phase of said input signal in accordance with a level of an output signal detected by said second level detection means; and wherein at least one of said input and output signals is provided through a branching circuit and wherein said branching circuit includes means for controlling the level of a signal to be provided.
Claim 15
Dependent Claim 15 words
The amplifier as claimed in claim 6, wherein said amplifying means is a power amplifier.
Claim 16
Dependent Claim 162 words
A linear compensating circuit for compensating a linearity of an input-output characteristic of amplifying means comprising: first level detection means for detecting a level of an input signal to be inputted to said amplifying means; second level detection means for detecting a level of an input signal to be inputted to said amplifying means; amplitude compensating means for controlling an amplitude of said input signal in accordance with a difference between a signal level detected by said first detection means and a signal level detected by said second detection means thereby improving a linearity of an input-output characteristic of said amplifying means; phase compensating means for controlling a phase of said input signal in accordance with a level of an output signal detected by said second level detection means; and a differential amplifier for amplifying a difference between an output of said first level detection means and an output of said second detection means to send it to said amplitude compensating means.
Claim 17
Dependent Claim 162 words
A linear compensating circuit for compensating a linearity of an input-output characteristic of amplifying means comprising: first level detection means for detecting a level of an input signal to be inputted to said amplifying means; second level detection means for detecting a level of an input signal to be inputted to said amplifying means; amplitude compensating means for controlling an amplitude of said input signal in accordance with a difference between a signal level detected by said first detection means and a signal level detected by said second detection means thereby improving a linearity of an input-output characteristic of said amplifying means; phase compensating means for controlling a phase of said input signal in accordance with a level of an output signal detected by said second level detection means; and a differential amplifier for amplifying a difference between an output of said first level detection means and an output of said second detection means to send it to said amplitude compensating means.
Claim 18
Dependent Claim 23 words
The linear compensating circuit as claimed in claim 11, wherein said amplitude compensating means is effective to increase and decrease said input signal.
Claim 19
Dependent Claim 54 words
The linear compensating circuit as claimed in claim 11, further comprising first and second branching circuits through which said input and output signals are taken out respectively, said first and second branching circuits being able to control a level of said signal to be sent out to said first and second detection means, respectively.
Claim 20
Dependent Claim 151 words
An amplifier comprising: amplifier means; first level detection means for detecting a level of an input signal to be inputted to said amplifying means; second level detection means for detecting a level of an output signal to be inputted to said amplifying means; amplitude compensating means for controlling an amplitude of said input signal in accordance with a difference between a signal level detected by said first detection means and a signal level detected by said second detection means to improve a linearity of an input-output characteristic of said amplifying means; phase compensating means for controlling a phase of said input signal in accordance with a level of an output signal detected by said second level detection means; and a differential amplifier for amplifying a difference between an output of said first level detection means and an output of said second detection means to send it to said amplitude compensating means.
Claim 21
Dependent Claim 151 words
An amplifier comprising: amplifier means; first level detection means for detecting a level of an input signal to be inputted to said amplifying means; second level detection means for detecting a level of an output signal to be inputted to said amplifying means; amplitude compensating means for controlling an amplitude of said input signal in accordance with a difference between a signal level detected by said first detection means and a signal level detected by said second detection means to improve a linearity of an input-output characteristic of said amplifying means; phase compensating means for controlling a phase of said input signal in accordance with a level of an output signal detected by said second level detection means; and a differential amplifier for amplifying a difference between an output of said first level detection means and an output of said second detection means to send it to said amplitude compensating means.
Claim 22
Dependent Claim 23 words
The linear compensating circuit as claimed in claim 14, wherein said amplitude compensating means has functions of increasing and decreasing said input signal.
Claim 23
Dependent Claim 53 words
The linear compensating circuit as claimed in claim 14, further comprising first and second branching circuits through which said input and output signals are taken out respectively, said first and second branching circuits being able to control a level of said signal to be sent out to said first and second detectors, respectively.

References Cited (Backward Citations)

US5101172A Cited
US5121077A Cited
US5124665A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1997-07-11 1998-01-10 1998-07-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2001-07-11 2002-01-10 2002-07-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2005-07-11 2006-01-10 2006-07-12 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag