Patent US4876654A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4876654A Expired / Lapsed US ⏱️ 0.0 years remaining

True RMS power demodulation system and method for a modulated RF signal

Assignee: Gresham Worldwide Inc
•
Filing: 1988-04-01
•
Granted: 1989-10-24
•
Expires: 2008-04-01
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract True RMS power demodulation system and method for a modulated RF signal uses a DC coupled linear amplifier and linearizes the diode detector prior to demodulation. The demodulated signal is proportional to the difference of RF powers such that the network measurement is unaffected by the modulation depth at the power sensor which can be degraded by RF feedthrough or the presence of an interfering signal or noise.

Inventors

  • 👤 Bret A. Herscher

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 16:25
CPC Classifications
G; G01; G01R; G01R19/00; G01R19/02

Claims Analysis

Total Claims: 32
Claim 1
Independent Claim 53 words
A method for true RMS power demodulation of an input signal comprising the steps of: detecting said input signal to provide a detected signal; linearly amplifying said detected signal to produce an amplified signal; linearizing said amplified signal to provide a converted signal; and, demodulating said converted signal to provide a demodulated signal.
Claim 2
Independent Claim 53 words
A method for true RMS power demodulation of an input signal comprising the steps of: detecting said input signal to provide a detected signal; linearly amplifying said detected signal to produce an amplified signal; linearizing said amplified signal to provide a converted signal; and, demodulating said converted signal to provide a demodulated signal.
Claim 3
Dependent Claim 19 words
The method of claim 1 wherein said step of detecting is carried out by means of a non-linear detector.
Claim 4
Dependent Claim 20 words
The method of claim 1 further comprising the steps of: logarithmically converting said demodulated signal to provide an output signal.
Claim 5
Independent Claim 152 words
A method for true RMS power demodulation of a modulation RF signal comprising the steps of: enabling a modulator to provide said modulated RF signal to a detector; detecting said modulated RF signal to provide a modulated detected signal; linearly amplifying said modulated detected signal to provide a modulated amplified signal; measuring a voltage level of said modulated amplified signal to establish V on ; disabling said modulator to provide an unmodulated RF signal to said detector; detecting said unmodulated RF signal to provide an unmodulated detected signal; linearly amplifying said unmodulated detected signal to provide an unmodulated amplified signal; measuring a voltage level of said unmodulated amplified signal to establish v off ; calculating a power level P on and P off respectively for said amplified signals V on and v off ; and, determining true RMS power of said modulated RF signal by subtracting P off from P on .
Claim 6
Independent Claim 152 words
A method for true RMS power demodulation of a modulation RF signal comprising the steps of: enabling a modulator to provide said modulated RF signal to a detector; detecting said modulated RF signal to provide a modulated detected signal; linearly amplifying said modulated detected signal to provide a modulated amplified signal; measuring a voltage level of said modulated amplified signal to establish V on ; disabling said modulator to provide an unmodulated RF signal to said detector; detecting said unmodulated RF signal to provide an unmodulated detected signal; linearly amplifying said unmodulated detected signal to provide an unmodulated amplified signal; measuring a voltage level of said unmodulated amplified signal to establish v off ; calculating a power level P on and P off respectively for said amplified signals V on and v off ; and, determining true RMS power of said modulated RF signal by subtracting P off from P on .
Claim 7
Dependent Claim 23 words
The method of claim 4 wherein said steps of enabling and disabling are carried out by means of a microcomputer controlled output latch.
Claim 8
Dependent Claim 19 words
The method of claim 4 wherein said steps of detecting are carried out by means of a non-linear detector.
Claim 9
Dependent Claim 21 words
The method of claim 4 wherein said steps of measuring are carried out by means of an A to D converter.
Claim 10
Dependent Claim 20 words
The method of claim 4 wherein said step of calculating and determining are carried out by means of a microcomputer.
Claim 11
Independent Claim 58 words
A system for true RMS power demodulation of an input signal comprising: means for detecting said input signal to provide a detected signal; linear amplifying means for producing an amplified signal from said detected signal; linearizing means to provide a converted signal from said amplified signal; and, means for demodulating said converted signal to provide a demodulated signal.
Claim 12
Independent Claim 58 words
A system for true RMS power demodulation of an input signal comprising: means for detecting said input signal to provide a detected signal; linear amplifying means for producing an amplified signal from said detected signal; linearizing means to provide a converted signal from said amplified signal; and, means for demodulating said converted signal to provide a demodulated signal.
Claim 13
Dependent Claim 12 words
The system of claim 9 wherein said detecting means comprises a diode.
Claim 14
Dependent Claim 19 words
The system of claim 9 further comprising: logarithmic converting means for providing an output signal from said demodulated signal.
Claim 15
Independent Claim 114 words
A system for true RMS power demodulation of a modulated RF signal comprising: means for enabling and disabling a modulator to provide a modulated and unmodulated input signals respectively; means for detecting said modulated and unmodulated input signals to provide first and second detected signals respectively; means for amplifying said first and second detected signals to provide first and second amplified signals respectively; means for measuring a voltage level of said first and second amplified signals; means for calculating a power level P on and P off for said first and second amplified signals respectively; and, means for determining true RMS power of said input signal by subtracting P off from P on .
Claim 16
Independent Claim 114 words
A system for true RMS power demodulation of a modulated RF signal comprising: means for enabling and disabling a modulator to provide a modulated and unmodulated input signals respectively; means for detecting said modulated and unmodulated input signals to provide first and second detected signals respectively; means for amplifying said first and second detected signals to provide first and second amplified signals respectively; means for measuring a voltage level of said first and second amplified signals; means for calculating a power level P on and P off for said first and second amplified signals respectively; and, means for determining true RMS power of said input signal by subtracting P off from P on .
Claim 17
Dependent Claim 18 words
The system of claim 12 wherein said means for enabling and disabling comprise a microcomputer controlled output latch.
Claim 18
Dependent Claim 13 words
The system of claim 12 wherein said means for detecting comprises a diode.
Claim 19
Dependent Claim 14 words
The system of claim 12 wherein said means for amplifying comprises a linear amplifier.
Claim 20
Dependent Claim 16 words
The system of claim 12 wherein said means for measuring comprises an A to D convertor.
Claim 21
Dependent Claim 14 words
The system of claim 12 wherein said calculating and determining means comprise a microcomputer.
Claim 22
Independent Claim 145 words
A method for true RMS power demodulation of a modulated RF signal comprising the steps of: providing an asynchronously modulated RF signal to a detector; detecting when said asynchronously modulated RF signal is modulated to provide a modulated detected signal; linearly amplifying said modulated detected signal to provide a modulated amplified signal; measuring a voltage level of said modulated amplifed signal to establish V on ; detecting when said asynchronously unmodulated RF signal is unmodulated to provide an unmodulated detected signal: linearly amplifying said unmodulated detected signal to provide an unmodulated amplified signal; measuring a voltage level of said unmodulated amplified signal to establish V off ; calculating a power level P on and P off respectively for said amplified signals V on and V off ; and, determining true RMS power of said modulated RF signal by subtracting P off from P on .
Claim 23
Independent Claim 145 words
A method for true RMS power demodulation of a modulated RF signal comprising the steps of: providing an asynchronously modulated RF signal to a detector; detecting when said asynchronously modulated RF signal is modulated to provide a modulated detected signal; linearly amplifying said modulated detected signal to provide a modulated amplified signal; measuring a voltage level of said modulated amplifed signal to establish V on ; detecting when said asynchronously unmodulated RF signal is unmodulated to provide an unmodulated detected signal: linearly amplifying said unmodulated detected signal to provide an unmodulated amplified signal; measuring a voltage level of said unmodulated amplified signal to establish V off ; calculating a power level P on and P off respectively for said amplified signals V on and V off ; and, determining true RMS power of said modulated RF signal by subtracting P off from P on .
Claim 24
Dependent Claim 19 words
The method of claim 18 wherein said steps of detecting are carried out by means of a non-linear detector.
Claim 25
Dependent Claim 21 words
The method of claim 18 wherein said steps of measuring are carried out by means of an A to D convertor.
Claim 26
Dependent Claim 20 words
The method of claim 18 wherein said steps of calculating and determining are carried out by means of a microcomputer.
Claim 27
Independent Claim 119 words
A system for true RMS power demodulation of an asynchronously modulated RF signal comprising: means for sensing a modulated and unmodulated portions of said RF signal to provide modulated and unmodulated input signals respectively; means for detecting said modulated and unmodulated input signals to provide first and second detected signals respectively; means for amplifying said first and second detected signals to provide first and second amplified signals respectively; means for measuring a voltage level of said first and second amplified signals; means for calculating a power level P on and P off for said first and second amplified signals respectively; and, means for determining true RMS power of said input signal by subtracting P off from P on .
Claim 28
Independent Claim 119 words
A system for true RMS power demodulation of an asynchronously modulated RF signal comprising: means for sensing a modulated and unmodulated portions of said RF signal to provide modulated and unmodulated input signals respectively; means for detecting said modulated and unmodulated input signals to provide first and second detected signals respectively; means for amplifying said first and second detected signals to provide first and second amplified signals respectively; means for measuring a voltage level of said first and second amplified signals; means for calculating a power level P on and P off for said first and second amplified signals respectively; and, means for determining true RMS power of said input signal by subtracting P off from P on .
Claim 29
Dependent Claim 13 words
The system of claim 22 wherein said means for detecting comprises a diode.
Claim 30
Dependent Claim 14 words
The system of claim 22 wherein said means for amplifying comprises a linear amplifier.
Claim 31
Independent Claim 16 words
The system of 22 claim wherein said means for measuring comprises an A to D convertor.
Claim 32
Dependent Claim 14 words
The system of claim 22 wherein said calculating and determining means comprise a microcomputer.

References Cited (Backward Citations)

US4160134A Cited
US4291277A Cited
US4453257A Cited
US4568878A Cited
US4679162A Cited
US4720673A Cited
US4758783A Cited
US4785419A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-10-23 1993-04-24 1993-10-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-10-23 1997-04-24 1997-10-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-10-23 2001-04-24 2001-10-24 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag