US4660045A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System for compensating polarization errors
Assignee: Lockheed Martin Corp
•
Filing: 1983-10-19
•
Granted: 1987-04-21
•
Expires: 2003-10-19
Abstract
Abstract A method and system is described for use with or in a satellite for compensating for cross coupling of satellite feeder link signals from a first channel of a first linear polarization as received by a first linearly polarized satellite antenna element with adjacent signals from a second channel. The second channel signals are at a generally orthogonal linear polarization. The system includes a second linearly polarized antenna element oriented orthogonal to the first antenna element for sensing the second channel signal, a gain controlled amplifier for reducing the gain of the second channel signal received at the second antenna element in inverse proportion to the sensed amount of cross coupling (depolarization) and adding the reduced gain signals that have been inverted to the first channel signals from said first antenna element.
Inventors
- 👤 John F. Clark
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 21:10
CPC Classifications
H; H04; H04B; H04B7/00; H04B7/002
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
205 words
A method for compensating for the cross coupling interference in first channel signals having a first sense of polarization as received at a first antenna pick-up means by second channel signals of a second opposite sense of polarization in a frequency reuse by polarization diversity system wherein signals in each of said first and second opposite sense polarizations are in given channels or frequency bands separated by a guard band and said channels in said first polarization are offset in frequency from said channels in said second polarization such that each channel center frequency of the second polarization is provided at the guard band between channels of the first polarization, said compensating method comprising the steps of: sensing the second channel signals by second pick-up means adapted to receive said second opposite sense polarization; sensing the ratio of the amplitudes of the second polarization signals at the guard band frequencies adjacent said first channel as received at said second and first antenna pick-up means; reducing the amplitude of the second channel signals sensed by the second antenna pick-up means in proportion to said ratio; and differentially summing said reduced amplitude second channel signals with said first channel signals received by said first antenna pick-up means.
Claim 2
Independent Claim
205 words
A method for compensating for the cross coupling interference in first channel signals having a first sense of polarization as received at a first antenna pick-up means by second channel signals of a second opposite sense of polarization in a frequency reuse by polarization diversity system wherein signals in each of said first and second opposite sense polarizations are in given channels or frequency bands separated by a guard band and said channels in said first polarization are offset in frequency from said channels in said second polarization such that each channel center frequency of the second polarization is provided at the guard band between channels of the first polarization, said compensating method comprising the steps of: sensing the second channel signals by second pick-up means adapted to receive said second opposite sense polarization; sensing the ratio of the amplitudes of the second polarization signals at the guard band frequencies adjacent said first channel as received at said second and first antenna pick-up means; reducing the amplitude of the second channel signals sensed by the second antenna pick-up means in proportion to said ratio; and differentially summing said reduced amplitude second channel signals with said first channel signals received by said first antenna pick-up means.
Claim 3
Dependent Claim
14 words
The method of claim 1 wherein said first and second polarizations are linear polarizations.
Claim 4
Dependent Claim
14 words
The method of claim 1 wherein said guard band is below said first channel.
Claim 5
Dependent Claim
14 words
The method of claim 1 wherein said guard band is above said first channel.
Claim 6
Dependent Claim
84 words
The method of claim 1 including sensing the difference in delay of the second polarization signals at the guard band frequencies adjacent said first channel as received at said second and first pick-up means, and wherein said differentially summing includes adjusting the relative phase of said second channel signals received by the second antenna pick-up means to the phase of said second channel signals received by the first antenna pick-up means in proportion to the sensed difference in delay at the guard band frequencies.
Claim 7
Dependent Claim
57 words
The method of claim 5 wherein said differentially summing adjusts the relative phase of said second channel signals received by the second antenna pick-up means to the phase of said second channel signals received by the first antenna pick-up means by an amount equal to 180° minus the sensed difference in delay at the guard band frequencies.
Claim 8
Independent Claim
233 words
A system for compensating for cross coupling interference in first channel signals having a first sense of polarization as received by a first antenna pick-up means by second channel signals having a second opposite sense of polarization in a frequency reuse by polarization diversity system wherein signals in each of said first and second opposite sense polarizations are in given channels or frequency bands separated by a guard band and said channels in said first polarization are offset in frequency from said channels in said second polarization such that each channel center frequency of the second polarization is provided at the guard band between channels of the first polarization, said compensating system comprising, in combination: means including a second antenna pick-up means adapted to receive said second opposite sense polarization for sensing the second channel signals; means coupled to said first and second antenna pick-up means for providing a gain control signal proportional to the ratio of the second channel signals at the guard band frequencies adjacent said first channel as received at said second and first antenna pick-up means, means coupled to said first and second mentioned means for reducing the amplitude of the second channel signals sensed by the second antenna pick-up means in proportion to said ratio; and means for differentially summing said reduced amplitude second channel signals with said first channel signals received by said first antenna pick-up means.
Claim 9
Independent Claim
233 words
A system for compensating for cross coupling interference in first channel signals having a first sense of polarization as received by a first antenna pick-up means by second channel signals having a second opposite sense of polarization in a frequency reuse by polarization diversity system wherein signals in each of said first and second opposite sense polarizations are in given channels or frequency bands separated by a guard band and said channels in said first polarization are offset in frequency from said channels in said second polarization such that each channel center frequency of the second polarization is provided at the guard band between channels of the first polarization, said compensating system comprising, in combination: means including a second antenna pick-up means adapted to receive said second opposite sense polarization for sensing the second channel signals; means coupled to said first and second antenna pick-up means for providing a gain control signal proportional to the ratio of the second channel signals at the guard band frequencies adjacent said first channel as received at said second and first antenna pick-up means, means coupled to said first and second mentioned means for reducing the amplitude of the second channel signals sensed by the second antenna pick-up means in proportion to said ratio; and means for differentially summing said reduced amplitude second channel signals with said first channel signals received by said first antenna pick-up means.
Claim 10
Dependent Claim
91 words
The system of claim 7 including means for sensing the difference in delay of the second polarization signals at the guard band frequencies adjacent said first channel as received at said second and first antenna pick-up means, and wherein said means for differentially summing includes means for adjusting the relative phase of said second channel signals received by the second antenna pick-up means to the phase of said second channel signals received by the first antenna pick-up means in proportion to said sensed difference in delay at the guard band frequencies.
Claim 11
Dependent Claim
72 words
The system of claim 8 wherein said means for adjusting the relative phase of said second channel signals includes means for adjusting the relative phase of said second channel signals received by the second antenna pick-up means to the phase of said second channel signals received by the first antenna pick-up means by an amount equal to 180° minus the amount of delay sensed at said means sensing a difference in delay.
Claim 12
Dependent Claim
14 words
The combination of claim 7 wherein said first and second polarizations are linear polarizations.
Claim 13
Dependent Claim
22 words
The combination of claim 7 wherein said second mentioned means includes means for sensing the guard band below said first channel frequencies.
Claim 14
Dependent Claim
22 words
The combination of claim 7 wherein said second mentioned means includes means for sensing the guard band above said first channel frequencies.
Claim 15
Dependent Claim
25 words
The combination of claim 7 wherein said second mentioned means includes means for sensing the guard band frequencies above and below said first channel frequencies.
Claim 16
Independent Claim
235 words
A system for compensating for cross coupling interference in first channel signals having a first sense of polarization as received by a first antenna pick-up means at a satellite by second channel signals having a second opposite sense of polarization in a frequency reuse by polarization diversity feeder link system wherein each of said first and second opposite sense polarized signals are in given channels or frequency bands separated by a guard band and said channels in said first polarization are offset in frequency from said channels in said second polarization such that the channel center frequency of the second polarization is provided at the guard band of said first polarization, said compensating system comprising in combination: means including a second antenna pick-up means adapted to receive said second opposite sense polarization for sensing the second channel signals; means coupled to said first and second antenna pick-up means for providing a gain control signal proportional to the ratio of the second channel signals at the guard band frequencies adjacent said first channel as received at said second and first antenna pick-up means; means coupled to said first and second mentioned means for reducing the amplitude of the second channel signals sensed by the second antenna pick-up means in proportion to said ratio; and means for differentially summing said reduced amplitude second channel signals within said first channel signals received by said first antenna pick-up means.
Claim 17
Independent Claim
235 words
A system for compensating for cross coupling interference in first channel signals having a first sense of polarization as received by a first antenna pick-up means at a satellite by second channel signals having a second opposite sense of polarization in a frequency reuse by polarization diversity feeder link system wherein each of said first and second opposite sense polarized signals are in given channels or frequency bands separated by a guard band and said channels in said first polarization are offset in frequency from said channels in said second polarization such that the channel center frequency of the second polarization is provided at the guard band of said first polarization, said compensating system comprising in combination: means including a second antenna pick-up means adapted to receive said second opposite sense polarization for sensing the second channel signals; means coupled to said first and second antenna pick-up means for providing a gain control signal proportional to the ratio of the second channel signals at the guard band frequencies adjacent said first channel as received at said second and first antenna pick-up means; means coupled to said first and second mentioned means for reducing the amplitude of the second channel signals sensed by the second antenna pick-up means in proportion to said ratio; and means for differentially summing said reduced amplitude second channel signals within said first channel signals received by said first antenna pick-up means.
Claim 18
Dependent Claim
23 words
The combination of claim 14 wherein said second mentioned means includes means for sensing the guard bands above and below said first channel.
Claim 19
Dependent Claim
11 words
The combination of claim 14 wherein said polarizations are linear polarizations.
Claim 20
Dependent Claim
91 words
The system of claim 14 including means for sensing the difference in delay of the second polarization signals at the guard band frequencies adjacent said first channel as received at said second and first antenna pick-up means, and wherein said means for differentially summing includes means for adjusting the relative phase of said second channel signals received by the second antenna pick-up means to the phase of said second channel signals received by the first antenna pick-up means in proportion to said sensed difference in delay at the guard band frequencies.
Claim 21
Dependent Claim
72 words
The system of claim 17 wherein said means for adjusting the relative phase of said second channel signals includes means for adjusting the relative phase of said second channel signals received by the second antenna pick-up means to the phase of the second channel signals received by the first antenna pick-up means by an amount equal to 180° minus the amount of delay sensed at said means sensing a difference in delay.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-04-20 | 1990-10-20 | 1991-04-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-04-20 | 1994-10-20 | 1995-04-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-04-20 | 1998-10-20 | 1999-04-21 | $7700.00 | Window Closed / Lapsed |