US3611394A - Louvered microwave reflector - Google Patents
Louvered microwave reflector Download PDFInfo
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- US3611394A US3611394A US887448A US3611394DA US3611394A US 3611394 A US3611394 A US 3611394A US 887448 A US887448 A US 887448A US 3611394D A US3611394D A US 3611394DA US 3611394 A US3611394 A US 3611394A
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- electromagnetic radiation
- reflector
- radiation beam
- receiving antenna
- stationary
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- 230000005670 electromagnetic radiation Effects 0.000 claims abstract description 80
- 230000000694 effects Effects 0.000 claims description 4
- 238000005562 fading Methods 0.000 abstract description 4
- 230000005540 biological transmission Effects 0.000 description 3
- 238000005452 bending Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000008054 signal transmission Effects 0.000 description 1
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Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/14—Relay systems
- H04B7/145—Passive relay systems
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q19/00—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic
- H01Q19/10—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using reflecting surfaces
- H01Q19/104—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using reflecting surfaces using a substantially flat reflector for deflecting the radiated beam, e.g. periscopic antennas
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q3/00—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system
- H01Q3/12—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system using mechanical relative movement between primary active elements and secondary devices of antennas or antenna systems
- H01Q3/16—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system using mechanical relative movement between primary active elements and secondary devices of antennas or antenna systems for varying relative position of primary active element and a reflecting device
- H01Q3/20—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system using mechanical relative movement between primary active elements and secondary devices of antennas or antenna systems for varying relative position of primary active element and a reflecting device wherein the primary active element is fixed and the reflecting device is movable
Definitions
- Jack L. Hummel ABSTRACT An electromagnetic radiation beam reflector which can be made transparent or reflective by rotating its elements. The reflector is used as a secondary reflector at a microwave receiving station to compensate for signal fading due to the refraction of the electromagnetic radiation beam which causes the beam to miss the primary reflector.
- This invention is related to the field of electromagnetic signal transmission and reception, and more specifically to the area of reflection of an electromagnetic radiation beam.
- a conventional corrective measure taken to restore the signal is to mount a parabolic dish receiving antenna about 40 feet below the primary stationary reflector.
- the parabolic dish antenna is connected to a second receiver by a pressurized waveguide.
- the secondreceiver system is utilized. This method of compensating for signal fade due to atmospheric refraction is costly due to the capital required for equipment.
- the present invention comprises a variable electromagnetic radiation beam reflector.
- the reflector may be mounted on an electromagnetic radiation beam receiving tower between the stationary reflector and the receiving antenna.
- the reflective surfaces of the variable reflector may be rotated such that an electromagnetic radiation beam may pass from the stationary reflector through the variable reflector to the receiving antenna or the reflective surfaces may be rotated such that an electromagnetic radiation beam is reflected from the variable reflector to the receiving antenna.
- the advantage of the present invention is that a second receiving antenna and a second receiver are not required during the periodswhen atmospheric refraction of electromagnetic radiation beams occurs.
- the invention may be utilized in an electromagnetic beam transmission system to avoid interruption due to atmospheric refraction of the electromagnetic beam.
- FIG. I shows a single-element variable electromagnetic radiation beam reflector
- FIG. 2 shows a multiple-element variable electromagnetic radiation beam reflector
- FIGS. 30 and 3b show a system designed to use a variable electromagnetic radiation beam reflector.
- the reflector of FIG. I comprises a reflective surface 1, an
- a suitable means of support for the surface at the axis 3 and a suitable means for causing rotation of the surface such as an actuating means comprising an actuator 4 and the connecting means 5.
- the device of FIG. 2 comprises a plurality of reflectors of the type shown in FIG. I mounted such that the axes lie in one plane and are parallel with respect to each other with a suitable means 4 and 5 for causing each individual reflector to rotate so that the reflectors remain parallel to each other at all positions of rotation.
- the reflectors are mounted in relation to each other such that they form a common surface when they are positioned in the same plane as the axes.
- FIG. 3 is a system comprising a tower 6, a stationary electromagnetic radiation beam reflector 7 mounted near the top of the tower, an electromagnetic radiation receiving antenna 8 mounted near the bottom of the tower, and a variable electromagnetic radiation beam reflector 9 mounted between the stationary reflector 7 and the receiving antenna 8.
- FIG. 3a shows a normal incoming electromagnetic radiation beam I0 which is reflected by reflector 7 through or past the variable electromagnetic radiation beam reflector 9 to receiving antenna 8.
- the reflective surfaces of reflector 9 arerotated to a position parallel with the beam passing between stationary reflector 7 and antenna 8.
- variable reflector 9 When the incoming electromagnetic radiation beam is refracted or displaced such that the beam strikes the tower 6 below stationary reflector 7 as illustrated by electromagnetic radiation beam 11, the reflective surfaces of variable reflector 9 are rotated to a position such that beam I1 is reflected to antenna 8.
- variable electromagnetic radiation reflector Although two embodiments of the variable electromagnetic radiation reflector and one system utilizing the unique advantages of the variable reflector have been illustrated, it will be understood that one experienced in the art of electromagnetic radiation beam transmission may be able to make various modifications or to derive other uses. Examples of other uses, which are not intended to limit the scope of the invention, are: the use of the variable reflector to allow the direction of one electromagnetic radiation beam to more than one target as illustrated by FIG. 3 if a transmitting antenna-or electromagnetic radiation beam source were substituted for the receiving antenna 8; use of the system shown in FIG. Jfor the reception of an electromagnetic radiation beam transmitted from more than one source as illustrated by substituting a beam from another source for the refracted beam 1 I. in FIG. 3.
- a stationary electromagnetic radiation beam reflector mounted above-the electromagnetic radiation receiving antenna in such a manner so as to reflect a normal incoming electromagnetic radiation beam to said receiving antenna
- a multiple-element variable electromagnetic radiation beam reflector comprising, in combination, more than one reflective surface, each surface being rotatable about an axis, the axes lying in a common plane and being parallel with relationship to each other, with a means of rotating the surfaces about said axes such that the surfaces are maintained substantially parallel at all positions of rotation, and a support means for supporting the rotatable surfaces, said support supporting the rotatable surfaces within the electromagnetic radiation beam passing between the receiving antenna and the stationary electromagnetic radiation beam reflector such that the surfaces may be alternately rotated about said axes to a first position parallel to the beam passing between the stationary reflector and the receiving antenna so as to allow the beam to pass substantially unaffected, and a second position such that a refracted incoming electromagnetic radiation beam which is caused to strike below the-stationary reflector may be reflected to the receiving anten- 2.
- a system which allows normal operation of an electromagnetic radiation beam receiving station and compensates for the effect of refraction of an electromagnetic radiation beam by the atmosphere when said beam is caused to miss the primary reflect
- a stationary electromagnetic radiation beam reflector mounted above the electromagnetic radiation receiving antenna in such a manner so as to reflect a normal incoming electromagnetic radiation beam to said receiving antenna
- variable electromagnetic radiation beam reflector comprising, in combination, at least one reflective surface, such surface being rotatable about an axis, and a support means for supporting the surface at the axis such that said axis is within or adjacent to the electromagnetic radiation beam passing between the stationary reflector and the receiving antenna such that the surface may be alternately rotated about said axis to a first position parallel to the beam so as to allow the beam to pass substantially unaffected and a second position such that a refracted incoming electromagnetic radiation beam which is caused to strike below the stationary reflector is reflected to the receiving antenna.
- variable electromagnetic radiation beam reflector mounted above the receiving antenna is used to reflect the normal incoming electromagnetic radiation beam to the receiving antenna and the stationary reflector mounted above the variable electromagnetic radiation beam reflector is used to reflect a refracted incoming electromagnetic radiation beam, which has been caused to strike above the variable reflector, through the variable reflector to the receiving antenna.
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- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Aerials With Secondary Devices (AREA)
- Variable-Direction Aerials And Aerial Arrays (AREA)
Abstract
An electromagnetic radiation beam reflector which can be made transparent or reflective by rotating its elements. The reflector is used as a secondary reflector at a microwave receiving station to compensate for signal fading due to the refraction of the electromagnetic radiation beam which causes the beam to miss the primary reflector.
Description
United States Patent lnventor Theodore Parker Elwood, lnd.
App]. No. 887,448
Filed Dec. 22, 1969 Patented Oct, 5, 1971 Assignee Marathon Oil Company Findlay, Ohio LOUVERED MICROWAVE REFLECTOR 4 Claims, 4 Drawing Figs.
US. Cl 343/761, 343/781, 343/837 Int. Cl H0lq 3/12 Field of Search 343/761 [56] References Cited UNITED STATES PATENTS 2,452,349 10/1948 Becker 343/761 2,754,513 7/1956 Goubau.... 343/839 2,977,464 3/1961 Engberg 343/912 Primary ExaminerEli Lieberman Att0rneys.loseph C. Herring, Richard C. Willson, Jr. and
Jack L. Hummel ABSTRACT: An electromagnetic radiation beam reflector which can be made transparent or reflective by rotating its elements. The reflector is used as a secondary reflector at a microwave receiving station to compensate for signal fading due to the refraction of the electromagnetic radiation beam which causes the beam to miss the primary reflector.
LOUVERED MICROWAVE REFLECTOR BACKGROUND OF THE INVENTION This invention is related to the field of electromagnetic signal transmission and reception, and more specifically to the area of reflection of an electromagnetic radiation beam.
During certain periods of the year, usually in the spring and fall, temperature inversions and other atmospheric conditions cause fading of microwave signals. This fading condition is occasionally the result of the bending or refraction of the microwave beam. When the beam has been displaced enough to miss the primary reflector at the receiving station, the signal is lost and the transmission system experiences an interruption.
A conventional corrective measure taken to restore the signal is to mount a parabolic dish receiving antenna about 40 feet below the primary stationary reflector. The parabolic dish antenna is connected to a second receiver by a pressurized waveguide. When the signal reflected from the primary stationary reflector and received by the primary receiver becomes weak due to atmospheric refraction of the electromagnetic radiation beam, the secondreceiver system is utilized. This method of compensating for signal fade due to atmospheric refraction is costly due to the capital required for equipment.
SUMMARY OF THE INVENTION The present invention comprises a variable electromagnetic radiation beam reflector. The reflector may be mounted on an electromagnetic radiation beam receiving tower between the stationary reflector and the receiving antenna. The reflective surfaces of the variable reflector may be rotated such that an electromagnetic radiation beam may pass from the stationary reflector through the variable reflector to the receiving antenna or the reflective surfaces may be rotated such that an electromagnetic radiation beam is reflected from the variable reflector to the receiving antenna.
The advantage of the present invention is that a second receiving antenna and a second receiver are not required during the periodswhen atmospheric refraction of electromagnetic radiation beams occurs. The invention may be utilized in an electromagnetic beam transmission system to avoid interruption due to atmospheric refraction of the electromagnetic beam.
The disadvantage of using a second receiving antenna and a second receiver during the periods when atmospheric refraction occurs is overcome by the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS The invention may be more fully understood by reference to the accompanying drawings, in which:
FIG. I shows a single-element variable electromagnetic radiation beam reflector;
FIG. 2 shows a multiple-element variable electromagnetic radiation beam reflector;
FIGS. 30 and 3b show a system designed to use a variable electromagnetic radiation beam reflector.
DESCRIPTION OF THE PREFERRED EMBODIMENTS The reflector of FIG. I comprises a reflective surface 1, an
axis of rotation 2, a suitable means of support for the surface at the axis 3, and a suitable means for causing rotation of the surface such as an actuating means comprising an actuator 4 and the connecting means 5.
The device of FIG. 2 comprises a plurality of reflectors of the type shown in FIG. I mounted such that the axes lie in one plane and are parallel with respect to each other with a suitable means 4 and 5 for causing each individual reflector to rotate so that the reflectors remain parallel to each other at all positions of rotation. The reflectors are mounted in relation to each other such that they form a common surface when they are positioned in the same plane as the axes.
FIG. 3 is a system comprising a tower 6, a stationary electromagnetic radiation beam reflector 7 mounted near the top of the tower, an electromagnetic radiation receiving antenna 8 mounted near the bottom of the tower, and a variable electromagnetic radiation beam reflector 9 mounted between the stationary reflector 7 and the receiving antenna 8.
The function of the:devices shown in FIG. I and FIG. 2 may be best illustrated by their use in the system shown in FIGS. 30 and 3b. FIG. 3a shows a normal incoming electromagnetic radiation beam I0 which is reflected by reflector 7 through or past the variable electromagnetic radiation beam reflector 9 to receiving antenna 8. The reflective surfaces of reflector 9 arerotated to a position parallel with the beam passing between stationary reflector 7 and antenna 8.
When the incoming electromagnetic radiation beam is refracted or displaced such that the beam strikes the tower 6 below stationary reflector 7 as illustrated by electromagnetic radiation beam 11, the reflective surfaces of variable reflector 9 are rotated to a position such that beam I1 is reflected to antenna 8.
Although two embodiments of the variable electromagnetic radiation reflector and one system utilizing the unique advantages of the variable reflector have been illustrated, it will be understood that one experienced in the art of electromagnetic radiation beam transmission may be able to make various modifications or to derive other uses. Examples of other uses, which are not intended to limit the scope of the invention, are: the use of the variable reflector to allow the direction of one electromagnetic radiation beam to more than one target as illustrated by FIG. 3 if a transmitting antenna-or electromagnetic radiation beam source were substituted for the receiving antenna 8; use of the system shown in FIG. Jfor the reception of an electromagnetic radiation beam transmitted from more than one source as illustrated by substituting a beam from another source for the refracted beam 1 I. in FIG. 3.
What is claimed is:
I. A system which allows normal operation of an electromagnetic radiation beam receiving station and compensates for the effect of refraction of an electromagnetic radiation beam by the atmosphere when said beam is caused to miss the primary reflector by said refraction, said system comprising in combination:
a. an electromagneticradiation receiving antenna mounted near the ground,
b. a stationary electromagnetic radiation beam reflector mounted above-the electromagnetic radiation receiving antenna in such a manner so as to reflect a normal incoming electromagnetic radiation beam to said receiving antenna,
a multiple-element variable electromagnetic radiation beam reflector comprising, in combination, more than one reflective surface, each surface being rotatable about an axis, the axes lying in a common plane and being parallel with relationship to each other, with a means of rotating the surfaces about said axes such that the surfaces are maintained substantially parallel at all positions of rotation, and a support means for supporting the rotatable surfaces, said support supporting the rotatable surfaces within the electromagnetic radiation beam passing between the receiving antenna and the stationary electromagnetic radiation beam reflector such that the surfaces may be alternately rotated about said axes to a first position parallel to the beam passing between the stationary reflector and the receiving antenna so as to allow the beam to pass substantially unaffected, and a second position such that a refracted incoming electromagnetic radiation beam which is caused to strike below the-stationary reflector may be reflected to the receiving anten- 2. A system which allows normal operation of an electromagnetic radiation beam receiving station and compensates for the effect of refraction of an electromagnetic radiation beam by the atmosphere when said beam is caused to miss the primary reflector by said refraction, said system comprising in combination:
a. an electromagnetic radiation receiving antenna mounted near the ground,
b. a stationary electromagnetic radiation beam reflector mounted above the electromagnetic radiation receiving antenna in such a manner so as to reflect a normal incoming electromagnetic radiation beam to said receiving antenna,
c. a variable electromagnetic radiation beam reflector comprising, in combination, at least one reflective surface, such surface being rotatable about an axis, and a support means for supporting the surface at the axis such that said axis is within or adjacent to the electromagnetic radiation beam passing between the stationary reflector and the receiving antenna such that the surface may be alternately rotated about said axis to a first position parallel to the beam so as to allow the beam to pass substantially unaffected and a second position such that a refracted incoming electromagnetic radiation beam which is caused to strike below the stationary reflector is reflected to the receiving antenna.
3. The system of claim 1 wherein the multiple-element variable electromagnetic radiation reflector mounted above the receiving antenna is used to reflect the normal incoming electromagnetic radiation beam to the receiving antenna and the stationary reflector mounted above the multiple-element electromagnetic radiation reflector is used to reflect a refracted incoming electromagnetic radiation beam, which has been caused to strike above the variable reflector, through the multiple-element reflector to the receiving antenna.
4. The system of claim 2 wherein the variable electromagnetic radiation beam reflector mounted above the receiving antenna is used to reflect the normal incoming electromagnetic radiation beam to the receiving antenna and the stationary reflector mounted above the variable electromagnetic radiation beam reflector is used to reflect a refracted incoming electromagnetic radiation beam, which has been caused to strike above the variable reflector, through the variable reflector to the receiving antenna.
Claims (4)
1. A system which allows normal operation of an electromagnetic radiation beam receiving station and compensates for the effect of refraction of an electromagnetic radiation beam by the atmosphere when said beam is caused to miss the primary reflector by said refraction, said system comprising in combination: a. an electromagnetic radiation receiving antenna mounted near the ground, b. a stationary electromagnetic radiation beam reflector mounted above the electromagnetic radiation receiving antenna in such a manner so as to reflect a normal incoming electromagnetic radiation beam to said receiving antenna, c. a multiple-element variable electromagnetic radiation beam reflector comprising, in combination, more than one reflective surface, each surface being rotatable about an axis, the axes lying in a common plane and being parallel with relationship to each other, with a means of rotating the surfaces about said axes such that the surfaces are maintained substantially parallel at all positions of rotation, and a support means for supporting the rotatable surfaces, said support supporting the rotatable surfaces within the electromagnetic radiation beam passing between the receiving antenna and the stationary electromagnetic radiation beam reflector such that the surfaces may be alternately rotated about said axes to a first position parallel to the beam passing between the statioNary reflector and the receiving antenna so as to allow the beam to pass substantially unaffected, and a second position such that a refracted incoming electromagnetic radiation beam which is caused to strike below the stationary reflector may be reflected to the receiving antenna.
2. A system which allows normal operation of an electromagnetic radiation beam receiving station and compensates for the effect of refraction of an electromagnetic radiation beam by the atmosphere when said beam is caused to miss the primary reflector by said refraction, said system comprising in combination: a. an electromagnetic radiation receiving antenna mounted near the ground, b. a stationary electromagnetic radiation beam reflector mounted above the electromagnetic radiation receiving antenna in such a manner so as to reflect a normal incoming electromagnetic radiation beam to said receiving antenna, c. a variable electromagnetic radiation beam reflector comprising, in combination, at least one reflective surface, such surface being rotatable about an axis, and a support means for supporting the surface at the axis such that said axis is within or adjacent to the electromagnetic radiation beam passing between the stationary reflector and the receiving antenna such that the surface may be alternately rotated about said axis to a first position parallel to the beam so as to allow the beam to pass substantially unaffected and a second position such that a refracted incoming electromagnetic radiation beam which is caused to strike below the stationary reflector is reflected to the receiving antenna.
3. The system of claim 1 wherein the multiple-element variable electromagnetic radiation reflector mounted above the receiving antenna is used to reflect the normal incoming electromagnetic radiation beam to the receiving antenna and the stationary reflector mounted above the multiple-element electromagnetic radiation reflector is used to reflect a refracted incoming electromagnetic radiation beam, which has been caused to strike above the variable reflector, through the multiple-element reflector to the receiving antenna.
4. The system of claim 2 wherein the variable electromagnetic radiation beam reflector mounted above the receiving antenna is used to reflect the normal incoming electromagnetic radiation beam to the receiving antenna and the stationary reflector mounted above the variable electromagnetic radiation beam reflector is used to reflect a refracted incoming electromagnetic radiation beam, which has been caused to strike above the variable reflector, through the variable reflector to the receiving antenna.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US88744869A | 1969-12-22 | 1969-12-22 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3611394A true US3611394A (en) | 1971-10-05 |
Family
ID=25391154
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US887448A Expired - Lifetime US3611394A (en) | 1969-12-22 | 1969-12-22 | Louvered microwave reflector |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US3611394A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5526008A (en) * | 1993-06-23 | 1996-06-11 | Ail Systems, Inc. | Antenna mirror scannor with constant polarization characteristics |
| US6307523B1 (en) * | 2000-05-15 | 2001-10-23 | Harris Corporation | Antenna apparatus and associated methods |
-
1969
- 1969-12-22 US US887448A patent/US3611394A/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5526008A (en) * | 1993-06-23 | 1996-06-11 | Ail Systems, Inc. | Antenna mirror scannor with constant polarization characteristics |
| US6307523B1 (en) * | 2000-05-15 | 2001-10-23 | Harris Corporation | Antenna apparatus and associated methods |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| AS | Assignment |
Owner name: MARATHON OIL COMPANY, AN OH CORP Free format text: ASSIGNS THE ENTIRE INTEREST IN ALL PATENTS AS OF JULY 10,1982 EXCEPT PATENT NOS. 3,783,944 AND 4,260,291. ASSIGNOR ASSIGNS A FIFTY PERCENT INTEREST IN SAID TWO PATENTS AS OF JULY 10,1982;ASSIGNOR:MARATHON PETROLEUM COMPANY;REEL/FRAME:004172/0421 Effective date: 19830420 |