US4958294A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Swept microwave power measurement system and method
Assignee: Gresham Worldwide Inc
•
Filing: 1988-04-01
•
Granted: 1990-09-18
•
Expires: 2008-04-01
Abstract
Abstract A swept microwave power measurement system and method capable of performing accurate high performance absolute power measurements on the fly for integration with a scalar analyzer. The system interpolates a calibration factor of the detector at a given frequency point in the sweep between previously established calibration factors at various predetermined frequencies which are stored in memory and then determines an "apparent" power level of the input signal at a standard frequency. The interpolated calibration factor is applied to the "apparent" power level to determine the "absolute" power level at the given frequency point in the sweep.
Inventors
- 👤 Bret A. Herscher
- 👤 Paul R. Munro
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 03:33
CPC Classifications
G; G01; G01R; G01R35/00; G01R35/005; G01R23/00; G01R23/16
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
146 words
A method for determining a swept absolute power level (P abs ) of an input signal within a scalar analyzer comprising the steps of: providing a detector calibrated at a plurality of predetermined frequencies (n) over a range of F min to F max ; storing a predetermined calibration factor (K(F n )) for said detector at each of said predetermined frequencies n; determining a frequency (F in ) of said input signal; interpolating a calibration factor K(F in ) of said input signal wherein said calibration factor K(F in ) is one of said predetermined calibration factors (K(F n )); establishing an apparent power level (P app ) of said input signal with respect to said calibration factor of a predetermined frequency standard; and correcting said apparent power level P app to said swept absolute power level P abs by application of K(F in ).
Claim 2
Independent Claim
146 words
A method for determining a swept absolute power level (P abs ) of an input signal within a scalar analyzer comprising the steps of: providing a detector calibrated at a plurality of predetermined frequencies (n) over a range of F min to F max ; storing a predetermined calibration factor (K(F n )) for said detector at each of said predetermined frequencies n; determining a frequency (F in ) of said input signal; interpolating a calibration factor K(F in ) of said input signal wherein said calibration factor K(F in ) is one of said predetermined calibration factors (K(F n )); establishing an apparent power level (P app ) of said input signal with respect to said calibration factor of a predetermined frequency standard; and correcting said apparent power level P app to said swept absolute power level P abs by application of K(F in ).
Claim 3
Dependent Claim
22 words
The method of claim 1 wherein said step of providing is carried out by calibrating said detector with respect to NBS Standards.
Claim 4
Dependent Claim
31 words
The method of claim 1 wherein said step of interpolating is carried out by means of a linear interpolation between calibration factors immediately preceding and succeeding said frequency F in .
Claim 5
Dependent Claim
22 words
The method of claim 1 wherein said step of storing is carried out by means of an EEPROM associated with said detector.
Claim 6
Dependent Claim
24 words
The method of claim 4 additionally comprising the step of reading said calibration factors K(F in ) from said EEPROM into an EEPROM interface.
Claim 7
Dependent Claim
13 words
The method of claim 1 wherein said predetermined frequency standard is 50 MHz.
Claim 8
Dependent Claim
21 words
The method of claim 6 wherein said step of measuring is carried out by means of an A to D convertor.
Claim 9
Dependent Claim
19 words
The method of claim 1 wherein said step of determining is carried out by measuring an analog sweep signal.
Claim 10
Dependent Claim
21 words
The method of claim 8 wherein said step of measuring is carried out by means of an A to D convertor.
Claim 11
Dependent Claim
33 words
The method of claim 8 wherein said step of determining is further carried out by means of a plurality of digital control signals coupling a source of said input signal with a microcomputer.
Claim 12
Dependent Claim
13 words
The method of claim 1 wherein said input signal is a swept signal.
Claim 13
Dependent Claim
18 words
The method of claim 11 further comprising the step of displaying a visual representation of swept absolute power.
Claim 14
Dependent Claim
18 words
The method of claim 12 wherein said step of displaying is carried out by means of a CRT.
Claim 15
Dependent Claim
21 words
The method of claim 12 wherein said step of displaying is sufficiently rapid to allow real time tuning of a component.
Claim 16
Independent Claim
170 words
A system within a scalar analyzer for determining a swept absolute power level (P abs ) of an input signal from a source comprising: means coupled to said source for detecting said input signal calibrated at a plurality of predetermined frequencies (n) over a range of F min to F max ; means coupled to said detecting means for storing a predetermined calibration factor (K(F n )) at each of said predetermined n frequencies; means coupled to a sweep voltage line of said source for determining a frequency (F in ) of said input signal; means coupled to said determining means for interpolating a calibration factor K(F in ) of said input signal; means coupled to said interpolating means for establishing an apparent power level (P app ) of said input signal with respect to a frequency standard; and, means coupled to said establishing means for correcting said apparent power level P app to said swept absolute power level P abs by application of said calibration factor K(F in ).
Claim 17
Independent Claim
170 words
A system within a scalar analyzer for determining a swept absolute power level (P abs ) of an input signal from a source comprising: means coupled to said source for detecting said input signal calibrated at a plurality of predetermined frequencies (n) over a range of F min to F max ; means coupled to said detecting means for storing a predetermined calibration factor (K(F n )) at each of said predetermined n frequencies; means coupled to a sweep voltage line of said source for determining a frequency (F in ) of said input signal; means coupled to said determining means for interpolating a calibration factor K(F in ) of said input signal; means coupled to said interpolating means for establishing an apparent power level (P app ) of said input signal with respect to a frequency standard; and, means coupled to said establishing means for correcting said apparent power level P app to said swept absolute power level P abs by application of said calibration factor K(F in ).
Claim 18
Dependent Claim
18 words
The system of claim 15 wherein said means for detecting comprises a microwave sensor calibrated to NBS standards.
Claim 19
Dependent Claim
33 words
The system of claim 15 wherein said means for interpolating comprises a microcomputer having as inputs said calibration factors (K(F n ) and a digital signal representative of said frequency F in .
Claim 20
Dependent Claim
27 words
The system of claim 15 wherein said means for correcting comprises a microcomputer having as input said apparent power level and said calibration factor K(F in ).
Claim 21
Dependent Claim
13 words
The system of claim 15 wherein said means for storing comprises an EEPROM.
Claim 22
Dependent Claim
15 words
The system of claim 19 further comprising an EEPROM interface serially coupled to said EEPROM.
Claim 23
Dependent Claim
22 words
The system of claim 15 wherein said means for determining comprises an A to D convertor coupled to a sweep voltage line.
Claim 24
Dependent Claim
23 words
The system of claim 21 further comprising a digital control signal bus coupled between said system and a source of said input signal.
Claim 25
Dependent Claim
28 words
The system of claim 15 wherein said means for establishing comprises an A to D convertor having as an input a signal V det from said detecting means.
Claim 26
Dependent Claim
21 words
The system of claim 23 wherein said means for establishing further comprises a microcomputer coupled to said A to D convertor.
Claim 27
Dependent Claim
12 words
The system of claim 24 wherein said frequency standard is 50 MHz.
Claim 28
Dependent Claim
13 words
The system of claim 15 wherein said input signal is a swept signal.
Claim 29
Dependent Claim
17 words
The system of claim 26 further comprising means for displaying a visual representation of swept absolute power.
Claim 30
Dependent Claim
12 words
The system of claim 27 wherein said displaying means comprises a CRT.
Claim 31
Dependent Claim
36 words
The system of claim 27 additionally comprising a component under test coupled between said swept signal and said means for detecting wherein said displaying means is sufficiently rapid to allow real time tuning of the component.
References Cited (Backward Citations)
US4418392A
Cited
US4381485A
Cited
US4414638A
Cited
US4556841A
Cited
US4703433A
Cited
US4652816A
Cited
US4667151A
Cited
US4680538A
Cited
US4758776A
Cited
US4713608A
Cited
US4777429A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-09-17 | 1994-03-19 | 1994-09-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-09-17 | 1998-03-19 | 1998-09-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-09-17 | 2002-03-19 | 2002-09-18 | $7700.00 | Window Closed / Lapsed |