Patent US5867064A successfully refreshed from Google Patents.
← Back to Patent Explorer
US5867064A Expired / Lapsed US ⏱️ 0.0 years remaining

Method and apparatus for improving intermodulation in a feed-forward amplifier

Assignee: Google Technology Holdings LLC
•
Filing: 1996-08-19
•
Granted: 1999-02-02
•
Expires: 2016-08-19
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A feed-forward amplifier (600) has an error path (123) replaced by a feed-forward amplifier (603) in a nested feed-forward configuration. By replacing the error path (123) with the feed-forward amplifier (603), design parameters such as efficiency and power output which are difficult to achieve with the conventional error path (123) are easily achieved with the single loop feed-forward amplifier (603). In this configuration, the main path (613) of the feed-forward amplifier (603) is capable of operating in a more efficient Class AB mode while still operating over a large dynamic range with to provide a relatively constant gain/phase relationship, thus insuring good intermodulation performance. The error path (627) of the feed-forward amplifier (603) must still be biased Class A, but it's requirements are much less than those of a Class A error amplifier (124) in an un-nested configuration.

Inventors

  • 👤 Mark I. Van Horn
  • 👤 Joe Clark
  • 👤 Leroy Plymale

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 15:22
CPC Classifications
H; H03; H03F; H03F1/00; H03F1/32; H03F1/3223; H03F1/3229; H03F2201/00; H03F2201/32; H03F2201/3218

Claims Analysis

Total Claims: 19
Claim 1
Independent Claim 87 words
A feed-forward amplifier comprising: a main amplifier, the main amplifier being a non-feed-forward amplifier having a main path for amplifying a carrier portion and an error portion of an input signal; and a second feed-forward amplifier, the second feed-forward amplifier including an error amplifier which is itself a feed-forward amplifier, the main amplifier being coupled, in a feed-forward arrangement, to the error amplifier via the main path, for canceling the error portion from the input signal to produce an output signal having the carrier portion substantially thereon.
Claim 2
Dependent Claim 87 words
A feed-forward amplifier comprising: a main amplifier, the main amplifier being a non-feed-forward amplifier having a main path for amplifying a carrier portion and an error portion of an input signal; and a second feed-forward amplifier, the second feed-forward amplifier including an error amplifier which is itself a feed-forward amplifier, the main amplifier being coupled, in a feed-forward arrangement, to the error amplifier via the main path, for canceling the error portion from the input signal to produce an output signal having the carrier portion substantially thereon.
Claim 3
Dependent Claim 18 words
The feed-forward amplifier of claim 1, wherein the second feed-forward amplifier includes a main path and error path.
Claim 4
Dependent Claim 25 words
The feed-forward amplifier of claim 2, wherein the main path of the second feed-forward amplifier includes an amplifier biased either Class A or Class AB.
Claim 5
Dependent Claim 25 words
The feed-forward amplifier of claim 2, wherein the error path of the second feed-forward amplifier includes an amplifier biased either Class A or Class AB.
Claim 6
Dependent Claim 21 words
The feed-forward amplifier of claim 1, wherein the second feed-forward amplifier has as an input an output of the main path.
Claim 7
Dependent Claim 50 words
The feed-forward amplifier of claim 5, wherein the second feed-forward amplifier and the output of the main path have an amplifier biased either Class A or Class AB coupled therebetween, the amplifier being coupled in series to a feed-forward corrected portion of an error path of the second feed-forward amplifier.
Claim 8
Dependent Claim 106 words
A feed-forward amplifier comprising: a main amplifier, the main amplifier being a non-feed-forward amplifier having a first main path for amplifying a carrier portion and an error portion of an input signal to produce an output signal; and a second feed-forward amplifier, the second feed-forward amplifier including an error amplifier which is itself a feed-forward amplifier, the main amplifier being coupled, in a feed-forward arrangement, to the error amplifier via the main path, the second feed-forward amplifier including a second main path and an error path, for canceling the error portion from the input signal to produce an output signal having the carrier portion substantially thereon.
Claim 9
Dependent Claim 106 words
A feed-forward amplifier comprising: a main amplifier, the main amplifier being a non-feed-forward amplifier having a first main path for amplifying a carrier portion and an error portion of an input signal to produce an output signal; and a second feed-forward amplifier, the second feed-forward amplifier including an error amplifier which is itself a feed-forward amplifier, the main amplifier being coupled, in a feed-forward arrangement, to the error amplifier via the main path, the second feed-forward amplifier including a second main path and an error path, for canceling the error portion from the input signal to produce an output signal having the carrier portion substantially thereon.
Claim 10
Dependent Claim 26 words
The feed-forward amplifier of claim 7, wherein the first and second main paths and the error path include amplifiers biased either Class A or Class AB.
Claim 11
Dependent Claim 21 words
The feed-forward amplifier of claim 7, wherein the second feed-forward amplifier has as an input an output of the main path.
Claim 12
Dependent Claim 50 words
The feed-forward amplifier of claim 9, wherein the second feed-forward amplifier and the output of the main path have an amplifier biased either Class A or Class AB coupled therebetween, the amplifier being coupled in series to a feed-forward corrected portion of the error path of the second feed-forward amplifier.
Claim 13
Dependent Claim 150 words
A feed-forward amplifier comprising: a first main path having a first amplifier, the first amplifier being a non-feed-forward amplifier for amplifying a carrier portion and an error portion of an input signal to produce a first output signal; a second amplifier, coupled in a feed-forward arrangement to the first amplifier, for amplifying the first output signal to produce an amplified first output signal; and a second feed-forward amplifier coupled, in a feed-forward arrangement, to the first amplifier and having as an input the amplified first output signal, the second feed-forward amplifier including a second main path having a third amplifier and an error path having an error amplifier, the second amplifier being coupled in series to a feed-forward corrected portion of the error path, the second feed-forward amplifier canceling the error portion from the amplified first output signal to produce a second output signal having the carrier portion substantially thereon.
Claim 14
Dependent Claim 150 words
A feed-forward amplifier comprising: a first main path having a first amplifier, the first amplifier being a non-feed-forward amplifier for amplifying a carrier portion and an error portion of an input signal to produce a first output signal; a second amplifier, coupled in a feed-forward arrangement to the first amplifier, for amplifying the first output signal to produce an amplified first output signal; and a second feed-forward amplifier coupled, in a feed-forward arrangement, to the first amplifier and having as an input the amplified first output signal, the second feed-forward amplifier including a second main path having a third amplifier and an error path having an error amplifier, the second amplifier being coupled in series to a feed-forward corrected portion of the error path, the second feed-forward amplifier canceling the error portion from the amplified first output signal to produce a second output signal having the carrier portion substantially thereon.
Claim 15
Dependent Claim 22 words
The feed-forward amplifier of claim 11, wherein the first, second, third and error amplifiers are biased either Class A or Class AB.
Claim 16
Independent Claim 100 words
A method of improving intermodulation in a feed-forward amplifier, the method comprising the steps of: amplifying, via a first non-feed-forward amplifier, a carrier portion and an error portion of an input signal to produce a first output signal; amplifying, via a second amplifier coupled in a feed-forward arrangement to the first amplifier, the first output signal to produce an amplified first output signal; and canceling, via a second feed-forward amplifier coupled in a feed-forward arrangement to the first amplifier, the error portion from the amplified first output signal to produce a second output signal having the carrier portion substantially thereon.
Claim 17
Independent Claim 100 words
A method of improving intermodulation in a feed-forward amplifier, the method comprising the steps of: amplifying, via a first non-feed-forward amplifier, a carrier portion and an error portion of an input signal to produce a first output signal; amplifying, via a second amplifier coupled in a feed-forward arrangement to the first amplifier, the first output signal to produce an amplified first output signal; and canceling, via a second feed-forward amplifier coupled in a feed-forward arrangement to the first amplifier, the error portion from the amplified first output signal to produce a second output signal having the carrier portion substantially thereon.
Claim 18
Dependent Claim 43 words
The method of claim 13, wherein the second feed-forward amplifier includes a second main path having a third amplifier and an error path having an error amplifier, the second amplifier being coupled in series to a feed-forward corrected portion of the error path.
Claim 19
Dependent Claim 21 words
The method of claim 14, wherein the first, second, third and error amplifiers are biased either Class A or Class AB.

References Cited (Backward Citations)

US5386198A Cited
US5304945A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2002-02-01 2002-08-03 2003-02-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2006-02-01 2006-08-03 2007-02-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2010-02-01 2010-08-03 2011-02-02 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag