Silicon window infrared augmenter

Information

  • Patent Grant
  • 6571714
  • Patent Number
    6,571,714
  • Date Filed
    Wednesday, December 26, 2001
    22 years ago
  • Date Issued
    Tuesday, June 3, 2003
    21 years ago
Abstract
There is provided an electrically powered augmenter device that has a silicon window. The silicon window emits the infrared radiation from the augmenter in a specific waveband, to attract heat seeking missles. Moreover, the augmenter may be mounted on the fuselage of an unpowered aerial towed target or other airborne vehicle.
Description




CROSS-REFERENCE TO RELATED APPLICATIONS




(Not Applicable)




STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT




(Not Applicable)




BACKGROUND OF THE INVENTION




The present invention relates generally to aerial targets, and more particularly to an improved aerial target decoy which simulates an exhaust of a jet engine through use of an infrared augmenter device having a silicon window.




The use of aerial targets to enhance military weapons training is well known. As shown in

FIG. 1

, aircraft typically tow these aerial targets so that they duplicate battle targets (e.g., enemy aircraft). By providing a scenario which closely resembles a real-life battle situation, target-striking weapons such as anti-aircraft missiles can be launched thereagainst so as to optimize their use and operation.




Certain types of aerial targets utilized in the military weapons training are adapted for more sophisticated weaponry such as heat-seeking missiles. These types are not only designed to provide visual indications of the targets' locations, but further emit infrared thermal; signatures. In this respect, military weaponry such as heat-seeking missiles can trace and follow the thermal signatures to strike and destroy those targets that emit them. By incorporating these types of aerial targets into the military weapons training, the operation and use of heat-seeking weaponry can be significantly improved in preparation for real-life situations.




Traditionally, gas or liquid fuel powered aerial targets have been used to achieve this purpose. These fuel-burning targets typically operate to heat a mesh or to create an external flame which radiates sufficient thermal signature. However, because such targets require fuel tanks, plumbing, valves and an ignition source, they are complicated and expensive. They also are limited in altitude and airspeed of operation. A further disadvantage is that their infrared emission is primarily directed aft. Thus, they are poorly suited in training pilots to attack an enemy heading toward them.




One known solution to this problem is the use of aerial targets manufactured by Global Target Systems Limited of Challock, Great Britain. Generally, a typical aerial target from Global comprises an enclosed housing which places a heater unit therein to selectively emit thermal signatures through its window. Although its targets are believed to be proven effective for their intended purpose, they are extremely expensive to manufacture. Simply put, these targets are too impractical as to cost to serve as one-time target designations.




Perhaps the greatest cost factor in manufacturing Global's aerial targets is the use of zinc-sulphide windows in their targets. In particular, Global's use of zinc-sulphide windows is due to the fact that they allow frequencies of infrared to radiate therethrough which can be readily detected by heat-seeking weaponry. However, these windows are extremely costly, not to mention that they are often difficult to obtain and/or fabricate. This becomes a tremendous factor when considering that aerial targets, by their inherent nature, are manufactured to be used for one-time target practice.




In view of the above-described shortcomings of conventional aerial targets, there exists a need in the art for an aerial target which can be economically manufactured. More specifically, there exists a need for an aerial target adapted for heat-seeking weaponry which generates and emits the required infrared thermal signature therefor, while being mass-producible with mitigated costs.




BRIEF SUMMARY OF THE INVENTION




The present invention specifically addresses and alleviates the above-referenced deficiencies associated with the use of aerial targets of the prior art. More particularly, the present invention is an improved aerial target which simulates an exhaust of a jet engine through use of an infrared augmenter device having a silicon window. This specific augmenter of the present invention is designed to continuously output the required infrared thermal signature in the forward direction as it is advantageously insensitive to mounting orientation. In addition, it is advantageously insensitive to airspeed and altitude. More importantly, however, the present invention's aerial target decoy uses a silicon window to radiate detectable infrared frequencies therethrough, which is significantly cheaper and more easily obtainable than the conventional windows performing the same.




In accordance with a preferred embodiment of the present invention, there is provided an unpowered aerial target for emitting an infrared thermal signature in a specific waveband range (about 3 to 5 microns) when being towed by an aircraft. The present invention features an infrared augmenter device which is engaged to the forward end of a fuselage. However, because the present augmenter device is adapted to consistently emit thermal signature through its window, it would be recognized that the augmenter can be placed any desired location defined on the fuselage.




In the preferred embodiment of the present invention, the silicon window may be incorporated into the infrared augmenter device in any sensible fashion, whether it be via conventional or creative means. Preferably, however, the silicon window is mounted in the front end of the augmenter device by an O-ring that acts like a snap-ring. This manner of attachment is further preferred as it helps prevent outside dust and moisture from entering within the device.




In operation, an aircraft may tow the present invention's aerial target by connecting elongated tow line to the target. By doing so, the target becomes airborne but should be far enough from the aircraft (about 2 miles) so that any incoming missiles do not inadvertently harm the aircraft. When airborne, the infrared augmenter device is operative to electrically generate high-intensity heat (about 1,400°F.) therewithin whereat its silicon window allows continuous emission of required infrared signatures of approximately 40 watts per steradian in the 3-5 micron waveband. In this respect, military weaponry such as heat-seeking missiles can be launched to trace these signatures for the purpose of striking and destroying the aerial target that emits them.











BRIEF DESCRIPTION OF THE DRAWINGS




These as well as other features of the present invention will become more apparent upon reference to the drawings wherein:





FIG. 1

is a side view of an aircraft towing a prior art aerial target (not drawn to scale) when conducting a military weapons training;





FIG. 2

is a perspective view of an aerial target utilized for emitting infrared thermal signatures constructed in accordance with a preferred embodiment of the present invention;





FIG. 3

is a perspective view of an infrared augmenter device featured in the aerial target of FIG.


2


and comprising a silicon window which is mounted therein;





FIG. 4

is a cross-sectional view of the infrared augmenter device of FIG.


3


and illustrating its internally disposed heating elements; and





FIG. 5

is a cross-sectional view of the infrared augmenter device of FIG.


3


and illustrating layers of insulation which are strategically arranged therein.











DETAILED DESCRIPTION OF THE INVENTION




Referring now to the drawings wherein the showings are for purposes of illustrating preferred embodiments of the present invention only, and not for purposes of limiting the same,

FIG. 2

perspectively illustrates an infrared augmenter device


10


constructed in accordance with a preferred embodiment of the present invention. As indicated above, the infrared augmenter device


10


is adapted to emit an infrared thermal signature


12


in the forward direction


14


. Those of ordinary skill in the art will recognize that the augmenter device


10


may be formed to have a variety of shapes, configurations, geometries and sizes other than for that shown in the provided figures.




As shown in

FIG. 3

, the infrared augmenter device


10


is enclosed in a housing


16


. Although the housing


16


is shaped in a cylindrical configuration, such depiction is exemplary in nature and should not be limited thereto. The housing


16


may be fabricated from any material, but is preferably fabricated from a metallic material, and even more preferably aluminum.




Referring more particularly to FIGS.


4


and


5


,there is provided a plurality of heating elements


24


that are disposed within the internal compartment


22


of the housing


16


. It would be known to a person of ordinary skill in the art that the number of heating elements


24


may vary. For example, there could be only one heating element


24


, or more than three. Rather, it is the concept of generating heat


26


within the internal compartment


22


that should be appreciated. In the preferred embodiment, however, three heating elements


24


should be used for optimization.




The three heating elements


24


are concentrically disposed within the internal compartment


22


of the housing


16


(best shown in FIG.


5


). Although each of the heating elements


24


may be characterized by various shapes and configurations, the ones of the present invention each generally has an a circular configuration. These heating elements


24


further include electrical input terminals


28


which extend and protrude through the back end


20


of the housing


16


(as shown in FIG.


4


). In this regard, the back end


20


is preferably a metallic backplate, and more particularly an aluminum backplate, which provides sufficient clearance holes


30


for the input terminals


28


to extend therethrough.




Referring now to

FIGS. 2 and 4

, the electrical input terminals


28


are in communication with an electrical power source


31


for supplying power thereto. More specifically, the heating elements


24


can be connected in parallel to the power source


31


. These elements


24


can be sized for 28 VDC, or can be designed in a manner as to be adapted for any type of power. The power source may be located within the fuselage


34


. In the alternative, the requisite electricity may be drawn from an outside power source such as from an aircraft


50


for example through an electrical cable which is elongated within the connecting tow line


52


. Moreover, there is further provided an insulating plate


36


disposed between the back end


20


and the forward end


32


to which the electrical input terminals


28


are mounted.




Referring more particularly to

FIGS. 3 and 4

, the infrared augmenter device


10


comprises a window


38


which is preferably fabricated from silicon. It is expressly stated herein that the use of a silicon window to radiate detectable infrared signature


12


is both advantageous and imperative to the present invention as it is significantly cheaper, sufficiently rugged and more easily obtainable than the conventional windows (e.g., zinc-sulphide windows) performing the same.




Preferably, the silicon window


38


is mounted within an opening


42


of the housing's front end


18


by an O-ring that acts like a snap-ring and further simultaneously mitigating outside dust and moisture from entering within the device


10


. However, it will be recognized by those of ordinary skill in the art that there are other methods of mounting the silicon window


38


within the housing


16


.




The silicon window


38


is preferably an anti-reflective window. In this respect, the silicon window is coated with an anti-reflective material. Moreover, as shown in

FIGS. 4 and 5

, there may further comprise insulation layers


48


which are selectively positioned within the internal compartment


22


of the housing


16


in a manner as to expo se the silicon window


38


to the generated heat


26


. Of course, these insulation layers


48


protect the housing


16


from heat


26


and further reduce heat losses in operation.




In operation, an aircraft


50


is utilized to tow the present invention's aerial target


40


by connecting an elongated tow line


52


thereto. However, it should be recognized by those of ordinary skill in the art that the present target


40


may be adapted for use with a variety of other vehicular structures (e.g., tanks, jeeps, gunboats, manned and unmanned fixed-wing aircraft and helicopters, etc.)




In particular, one end of the tow line


52


is connected to the aircraft


50


while the other end is connected to the fuselage


34


. By doing so, the decoy


40


becomes airborne but it should be emphasized that the decoy


40


should be sufficiently distanced from the aircraft


50


(about 2 miles)i so that any incoming missiles do not inadvertently harm the aircraft


50


.




When the present decoy


40


is airborne, the heating elements


24


are operative to electrically generate high-intensity heat


26


(about 1,4000° F.) within the internal compartment


22


. These heating elements


24


produce radiant heat


26


which is radiated through the silicon window


38


whereat the silicon window


38


allows continuous emission of required infrared signatures


12


. These signatures


12


are approximately 40 watts per steradian in the 3-5 micron waveband which are selected frequencies associated with infrared engines. In this respect, military weaponry such as heat-seeking missiles can be launched to trace these signatures


12


for the purpose of striking and destroying the aerial target


40


.




Additional modifications and improvements of the present invention may also be apparent to those of ordinary skill in the art. Thus, the particular combination of parts described and illustrated herein is intended to represent only certain embodiments of the present invention, and is not intended to serve as limitations of alternative devices within the spirit and scope of the invention.



Claims
  • 1. An infrared augmenter device for emitting an infrared thermal signature in a specific waveband range, the device comprising:a housing having a front end with an opening; at least one heating element disposed within the housing for generating heat therein; and a silicon window mounted within the opening of the front end and emitting the infrared thermal signature in the specific waveband range when the heat generated within the housing is radiated therethrough.
  • 2. The device of claim 1 wherein the housing is cylindrically configured.
  • 3. The device of claim 1 wherein the housing is fabricated from an aluminum material.
  • 4. The device of claim 1 wherein the housing has a back end and the at least one heating element comprises at least one electrical input terminal, the at least one heating element being connected to the back end via the at least one electrical input terminal extending therethrough.
  • 5. The device of claim 4 wherein the back end of the housing comprises at least one clearance hole for receiving the at least one electrical input terminal therethrough.
  • 6. The device of claim 4 wherein the at least one electrical input terminal is in communication with a electrical power source.
  • 7. The device of claim 1 wherein the at least one heating element comprises three heating elements.
  • 8. The device of claim 7 wherein the three heating elements are concentrically disposed within the housing.
  • 9. The device of claim 1 wherein the at least one heating element has a circular configuration.
  • 10. The device of claim 1 wherein the heat generated within the housing is approximately 1,400 degrees Fahrenheit.
  • 11. The device of claim 1 wherein the housing comprises insulation layers for maintaining the heat generated therein, the insulation layers being selectively positioned within the housing so as to expose the silicon window to the generated heat.
  • 12. The device of claim 1 wherein the front end comprises an inner periphery defining a continuous groove therearound, the silicon window being positioned within the groove so as to be secured thereby.
  • 13. The device of claim 1 wherein the silicon window is an anti-reflective window.
  • 14. The device of claim 1 wherein the silicon window is coated with an anti-reflective material.
  • 15. The device of claim 1 wherein the specific waveband range of the infrared thermal signature is about 3 to 5 microns.
  • 16. An unpowered aerial target for emitting an infrared thermal signature in a specific waveband range when being towed by an aircraft, the target comprising:a fuselage being connectable to the aircraft for allowing the fuselage to be towed thereby; and an infrared augmenter device engaged to one end of the fuselage and having a silicon window, the silicon window emitting the infrared thermal signature therefrom in the specific waveband range.
  • 17. The device of claim 16 wherein a tow line connects the fuselage to the aircraft.
  • 18. The device of claim 16 wherein a plurality of heating elements are concentrically disposed within the infrared augmenter device for generating heat therein, the silicon window emitting the infrared thermal signature in response to the teat being conducted therethrough.
  • 19. The device of claim 16 wherein the specific waveband range of the infrared thermal signature is about 3 to 5 microns.
  • 20. The device of claim 16 wherein the silicon window is coated with an anti-reflective material.
US Referenced Citations (53)
Number Name Date Kind
2381130 Lloyd Aug 1945 A
2448343 Zandmer Aug 1948 A
2551596 Haglund May 1951 A
2813719 Hopper Nov 1957 A
2907536 Vonzborowski Oct 1959 A
2923549 Hopper et al. Feb 1960 A
2953377 Brust Sep 1960 A
2998754 Bialy Sep 1961 A
3002708 Wetzel et al. Oct 1961 A
3135511 Norman et al. Jun 1964 A
3225655 Inglis Dec 1965 A
3410559 Miller, Jr. Nov 1968 A
3505926 Johnson Apr 1970 A
3610096 Bauman et al. Oct 1971 A
3720167 Mainhardt et al. Mar 1973 A
3808941 Biggs May 1974 A
3871321 Biebel et al. Mar 1975 A
3898661 Kelly et al. Aug 1975 A
3899975 Lawrence Aug 1975 A
3932057 Wadensten Jan 1976 A
4062112 Lake Dec 1977 A
4134008 de Corlieu et al. Jan 1979 A
4135027 Anthony et al. Jan 1979 A
4140433 Eckel Feb 1979 A
4195571 Becker et al. Apr 1980 A
4205848 Smith et al. Jun 1980 A
4406227 Becker et al. Sep 1983 A
4428583 Feagle Jan 1984 A
4446793 Gibbs May 1984 A
4599537 Yamashita Jul 1986 A
4607849 Smith et al. Aug 1986 A
4718320 Brum Jan 1988 A
4770368 Yates et al. Sep 1988 A
4796536 Yu et al. Jan 1989 A
4852455 Brum Aug 1989 A
4860657 Steinicke et al. Aug 1989 A
4899662 Santalucia et al. Feb 1990 A
5074216 Dunne et al. Dec 1991 A
5077143 Barraclough et al. Dec 1991 A
5179778 Dickson et al. Jan 1993 A
5249924 Brum Oct 1993 A
5312521 Fraas et al. May 1994 A
5319373 Maxwell et al. Jun 1994 A
5445078 Marion Aug 1995 A
5488371 Targove Jan 1996 A
5497156 Bushman Mar 1996 A
5499582 Schiessl et al. Mar 1996 A
5639984 Nielson Jun 1997 A
5670959 Nagura et al. Sep 1997 A
5680136 Chekroun Oct 1997 A
5693907 Rudnik Dec 1997 A
5915694 Brum Jun 1999 A
6204083 Kodato et al. Mar 2001 B1
Foreign Referenced Citations (2)
Number Date Country
1229397 Nov 1966 DE
1336769 Jul 1963 FR
Non-Patent Literature Citations (1)
Entry
Defense Electronics; “Expandable Decoys Counter Missle with New Technology”; Oct. 1986.