US2556046A - Directional antenna system - Google Patents

Directional antenna system Download PDF

Info

Publication number
US2556046A
US2556046A US657691A US65769146A US2556046A US 2556046 A US2556046 A US 2556046A US 657691 A US657691 A US 657691A US 65769146 A US65769146 A US 65769146A US 2556046 A US2556046 A US 2556046A
Authority
US
United States
Prior art keywords
horn
antenna
phase
wave
disc
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US657691A
Inventor
Oscar T Simpson
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Space Systems Loral LLC
Original Assignee
Space Systems Loral LLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Space Systems Loral LLC filed Critical Space Systems Loral LLC
Priority to US657691A priority Critical patent/US2556046A/en
Application granted granted Critical
Publication of US2556046A publication Critical patent/US2556046A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01QANTENNAS, i.e. RADIO AERIALS
    • H01Q19/00Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic
    • H01Q19/06Combinations 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 refracting or diffracting devices, e.g. lens
    • H01Q19/08Combinations 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 refracting or diffracting devices, e.g. lens for modifying the radiation pattern of a radiating horn in which it is located
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01QANTENNAS, i.e. RADIO AERIALS
    • H01Q13/00Waveguide horns or mouths; Slot antennas; Leaky-waveguide antennas; Equivalent structures causing radiation along the transmission path of a guided wave
    • H01Q13/02Waveguide horns
    • H01Q13/04Biconical horns
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01QANTENNAS, i.e. RADIO AERIALS
    • H01Q19/00Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic
    • H01Q19/06Combinations 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 refracting or diffracting devices, e.g. lens

Description

Patented June 5, 1951 UNITED isTATEs PATENT OFFICE 2556,046 DIREoi'ioNAi. ANTE'NNA SYSTEM Oscar T. Simpson, Philadelphia, Pa., assignor, by
mesne assinment's, tolfhilco Corporation, Philadelphia, Pal., a corporation of Pennsylvania Application March 28, 1948, serial No. 657,691
This invention relates to directional antenna systems adapted to radiate or receive ultra high frequency electromagnetic wave energy. More particularly, this invention has to do With novel means for improving and controlling the directional properties of directive antenna systems.
In consequence of the small physical dimen- .Sions of antennas and antenna systems available for use at ultra high frequencies, directional Wave propagaton is preferably accomplished through the use of simple antenna structures, such as horn radiators and refiector type antennas rather than by means of the more complicated and more critical antenna arrays usually employed at the lower radio frequencies.
The manner in which horn radiators and reflector type antennas function as a means of propagating electromagnetic wave energy in a desired direction is considered to be suificiently understoodl by those skilled in the art that only reference to some of the physical considerations of such antenna systems will be given here.
Highly directional radiation patterns may be obtained with simple horn radiators if the mouth or aperture is made large compared to the wavelength. Likewise, in a dipole and refiector type antenna system the width of the radiation pattem or beam becomes less as the diameter of the reflector mouth or aperture is increased. Thus for a given beam width, at a given frequency, these basic antenna structures must ne'cessarily have certain minimum dimensions.
.In many fiXed-service applications the dimen'- sions of the antenna system are not likely to be a significant factor. I-Iowever. in portable systems, and particularly in air-borne installations, it is important that the antennais physical dimensions, size, and weight be kept as small as' possible. Frequently it is equally important that the antenna may be constructed to have sufii-4 cient rigidity to withstand rough handling and vibraton in order that the electrical constants o f the system, and hence the radiation pattern, will not be subject to Variation.
The shape of the radiation pattern of a directive antenna system is primarily determined by the configuration of the wave front merging from the system. Thus a wave front having a high degree of curvature will give a comparatively wide beam, While a wave front of smallei' curvature will produce a narrower beam. In' horn radiators it has .been found that the' energy issuing from the mouth has a spherical wave front.
N ow I have found that by placing a phase' mod* ifyi'ng body in front of and along the axls ofa horn radiator I am able to s'ubstantia'llfy modify the radiataion pattern of the' 'propagatd energy. This phase-modifying body is preferably in the form of a metallic disc. With a disc of a certain siz'e placed at a certain distance in front of the' horn I am able greatly to increase the directivit'y of the mcdified horn over that of the horn alone. By means of the aforementioned arangement of a horn and a phase-modifying disc I am able to obtain a radiation pattern having a sp'e'cfi'd beam width With an antenna system which smalle'r and lightr than a conventio'nal horn capable of providing the same beam width;
'It is to be understood that my invention is not limited to the use of a horn radiator in om bination with a single phase-modifying body; II may employ in place of the horn other known devices for obtaining directional propagation of ultra high frequency energy, such as a dipole in combination with a spherical 'renector orH the like, and l may also use aplurality of phase modifying bodies of various configurations placed in various positions in front of the propagating device for the purpose of modifying or controlling the diree'tivity of the antenna system. i v
Thus, according to my invention,` VI proyidea novel means for altering the normalradi` pattern of a wave directing device by modifying the wave front of the energy issuing from the de'- vice. By modifying the wave front of the energy after it leaves the propagating device, I provide a directive antenna system that is more fiexible, more readily adjusted, less limited in its adjus't: ment, and capable of producing a greater variety of radiation pattern than known prior antenna systems. i
It is therefore an object of the present inven-`` tion to provide novel means for controlling the' directional characteristics of ultra high' frequency antenna systems.
Another object of this inventio'n is t improve the directional characteristicshof ultra high frequency antenna systems employing wave' directive striic'tures without increasing the physical dirriensions of the wave directive' structure.
Another object of the present invention' isto provide novel means for obtaining specialradiaftion patterns from ultra high frequency directive antenna systems.
Other objects and features of theppr'eent invention will become apparent from the following description taken' in conjunction with the ao' companying drawings in which: p
Fig's. IA and 1B are, respectively, side and'-` front elevation views illustrating one embodiment of the invention adapted to a horn radiator;
Figs. 2A and 2B are similar views illustrating another embodiment of the invention; and
Fig. 3 is a cross-sectional view of an alternative embodiment employing a biconical horn type of radiator.
Referring to the drawings, the horn radiator 4 together with wave guide 5 represents one forme of a conventional horn antenna system. The wave guide 5 may be excited in any well known manner, s-uch as by means of a capacity probe 6 extending into the guide from a coaxial cable input connection 1. Proper impedance match between the antenna system and a coaxial feeder cable attach-ed to connection 'i may be obtained by any one of the usual matching methods. For example, the non-radiating end of the waveguide 5 may be closed by a conducting end-plate preferably movable within the guide, and positioned at thecorrect distance from input connection i to give the desired impedance match. Since the above-mentioned elements comprise a well known arrangement of a horn antenna system a detailed description thereof is deemed unnecessary.
` At a given frequency a horn antenna has, of course, a radiation pattern of a certain gain and directivity depending upon the length of the horn, the horn flare angle, and the size of the mouth or aperture of the horn. With one of these factors fixed one or both of the others will have an Optimum Value for maximum directivity and gain.
To illustrate one manner in which the radiation pattern of a horn antenna may be modified in accordance with the principles herein set forth reference may be had to Figs. 1A and 1B. The arrangement shown may be employed to improve the directivity of the horn. To this end a metallic disc 9, acting as a director, is mounted in front of the horn, perpendicularly to and coaxially with the axis of the horn antenna system 4, 5. Any convenient and appropriate means may be employed to support the disc. By way of example, the phase-modifying disc 9 may be centrally apertured, as indicated at 9a, to engage dielectric supporting rod Ill which, in turn, is fixed to a dielectric' plate i i at the center thereof. As shown best in Fig. 1A, the plate i! may conveniently be supported by means of an annular flange |2 formed around the aperture of horn 4. If desired the metal disc may be slidably mounted on rod iii so that its axial position may be adjusted to produce a desired radiation pattern. The die1ectric elements I O and I should be composed of a substance or substances (e. g. a plastic or a ceramic) having low electrical losses, i. e., low power factor, at the opearting frequency. Polystyrene is an example of a suitable low loss plastic dielectric material. The determination of the size and position of disc 9 is more or less a cut and try" matter, with the size of the disc following the general rule that the phase-modifying body is preferably resonant at a slightly higher frequency than the energy being radiated.
In practicing this invention according to the Iembodiment shown in Figs. 1A and 1B, for the purpose of improving the directional properties of horn radiator 4, a 90 horn with Optimum length and aperture was excited in the TEu mode at a frequency of 2550 megacycles. The mouth of the horn was six and three-quarter inches in diameter and the distance from the mouth to the throat was one and three-quarter inches.
The diameter of wave guide 5 was three and onequarter inches. Dielectric supporting elements, rod IO and plate Il, consisted of a one-half inch diameter rod and a one-quarter inch sheet respectively of polystyrene. Several metallic director discs of various diameters were tested and it was found that to obtain maximum directivity with a given disc the distance of the disc from the horn was critical and a function of the disc diameter. Maximum directivity was obtained with a disc measuring just under a half-wavelength (21A inches) in diameter, and placed at a distance of approximately one-quarter wavelength (one and one-quarter inches) in front of the horn. With this particular arrangement the radiation pattern measured 30 in the horizontal plane and 34 in the Vertical plane. The radiation pattern of the horn alone measured 43 in the horizontal plane and 46 in the Vertical plane. The beam width in degrees as given above is with respect to the half power points.
As previously mentioned, this invention is not limited to the use of a single phase-modifying body; instead a pl'urality of such bodies, of various configurations, may be employed for the purpose of improving the directive properties of the antenna system or to obtain special radiation patterns. To illustrate such an embodiment of the invention, there is shown in Figs. 2A and 2B, by way of example, five phase-modifying metallic discs, 19, 20, 21, 22 and 23, all placed in front of horn 4. Preferably these elements are spaced from the mouth of Vthe hornfiloy a distance not greater than the diameter of the horn. The discs may be supported in any convenient manner. In the drawing a circular dielectric plate il, seated in the horn's annular fiange i2, supports a centrally positioned dielectric rod 25. Another ,circular dielectric plate 2G is centrally apertured to engage the supporting rod 25. Plate 25 carries themetallic phase-modifying discs E9, 20, 2|, and 22. The rod 25 is extended beyond the plane of plate 26 to carry a centrally positioned phasemodifying disc 23. The plate 26 and disc 23 may, of course, be arranged to be adjustably positioned on rod 25. It is evident that methods other than that shown in Fig. 2 for mountng the several phase modifying elements may be employed. For example, each of the discs lg to 22 may be mounted on separate rods projecting from plate I l to permit individual Variation of the distance of each element from the mouth of the horn for the purpose of obtaining still greater fiexibility and additional special pattern shapes. Although the phase-modifying bodies are illustrated as circular plates or discs, it is to be understood that talternatively they may be rectangular or ellipical.
Reference may now be had to the embodiment illustrated in Fig. 3 in which the present invention is applied to a directive radiator of the biconical horn type. The biconical horn is comprised of an upper conical member 30 and a centrally-apertured, lower conical member 3|. The foregoing elements, shown in section, are rotationally symmetrical about the Vertical axis X-X. The biconical horn may be driven in any known manner-for example by means of a coaxial line 32, the inner conductor 33 of which terminates in the apex 34 of the upper conical member 30.
In accordance with the present invention, Aa
phase modifying body 3'5, having the form of anv j -annular ring, is medially positioned between the conical members 3B and 3|. Preferably the diameter of the annular ring 35 is such as to place it Well beyond the mouth of the horn. For maximum directivity in a Vertical plane a spacing of approximtaely a quarter wavelength is suggested.
In the interests of clarity no means for supporting the ring 95 are shown; suitable supporting and spacing structures can, of course, be readily adapted from those illustrated in Figs. 1A and 1B.
The principles underlying the present invention have not yet been fully determined. It appears, however, that the phase-modifying discs (or the phase-modifying annular ring of Fig. 3) function as wave-refracting bodies which alter the phase of portions of the electromagnetic wave energy with respect to the phase of other portions thereof, and thus modify the radiation pattern of the antenna system. With specific reference to the embodiment of Figs. 1A and 1B, for example, it appears that the disc 9 tends to retard the phase of the wave passing therethrough, or in the vicinity thereof, in such manner as to more favorably phase the central portion of the radiated energy with respect to the outer portions thereof, and thus to convert the spherical Wave front of the conventional horn radiator to a more nearly plane wave front.
It will be apparent to those skilled in the art that the structures herein described may be utilized in either the reception or transmission of Wave energy, it being well understood that the characteristics of an antenna used to abstract energy from a passing wave are similar, in practically all respects, to those of the same structure used as a radiator.
Although this invention has been illustrated and described With reference to certain specific physical embodiments it is to be understood that the invention is not limited to such embodiments and that other apparatus and arrangements may be utilized within the scope of the invention as defined in the appended claims.
the plane of said mouth a distance of substan- 3. An ultra high frequency antenna system as claimed in claim 1, characterized in that the diameter of said disc is substanti-ally a half wavelength at the said Operating frequency.
An ultra high frequency antenna system comprising a horn radiator having a mouth through which electromagnetic wave energy may pass in a direction generally normal to the plane of said month, a dielectric plate seated in the mouth of said horn, a dielectrio rod centrally fixed to said plate and extcnding perpendicularly therefrom, and a phase-modifying wave-refraotive disc supported by said rod, said disc being Wholly outside of and spaced from said horn in a position coaxial With the axis of said horn, for altering the phase of a portion of said Wave energy with respect to other portions thereof, whereby to modify the radiation pattern of said horn.
5. An ultra high frequency antenna system as claimed in clairn 4, characterized in that said phase-modifying disc is electrically resonant at a frequency somewhat above the Operating frequency of said system.
6. An. ultra high frequency antenna system comprising a biconical horn radiator, said radiator being comprised of a pair of conical elements and having a month through which electromagnetic wave energy may pass, and a phasemodifying annular ring medially positoned between said conical elements, said annular ring being wholly outside of and spaced from said biconical horn, the diameter of said annular ring being greater than the rim-diameter of said biconical horn by substantially a half waveiength at the Operating frequency.
OSCAR T. SIMPSON.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 2,283,935 King May 26, 1942 2,370,053 Lindenblad Oct. 20, 1945 2,405,992 Bruce Aug. 20, 1946 2,415,089 Feldman Feb. 4, 1947 2,419,556 Feldman Apr. 29, 1947 2,429,601 Biskeborn et al. Oct. 28, 1947 2,442,951 Iams June 8, 1948 2,478,241 Chu Aug. 9, 1949 2.486,589 Chu Nov. 1, 1949 FOREIGN PATENTS Number Country Date 678,010 Germany June 24, 1939 694,523 Germany Aug. 2, 1940 OTHER. REFERENCES Electronics, March 1, 1946, page 101.
US657691A 1946-03-28 1946-03-28 Directional antenna system Expired - Lifetime US2556046A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US657691A US2556046A (en) 1946-03-28 1946-03-28 Directional antenna system

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US657691A US2556046A (en) 1946-03-28 1946-03-28 Directional antenna system
GB7696/47A GB647136A (en) 1946-03-28 1947-03-20 Directional antenna systems

Publications (1)

Publication Number Publication Date
US2556046A true US2556046A (en) 1951-06-05

Family

ID=24638256

Family Applications (1)

Application Number Title Priority Date Filing Date
US657691A Expired - Lifetime US2556046A (en) 1946-03-28 1946-03-28 Directional antenna system

Country Status (2)

Country Link
US (1) US2556046A (en)
GB (1) GB647136A (en)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2677767A (en) * 1949-06-04 1954-05-04 Int Standard Electric Corp Omnidirectional antenna
US2761139A (en) * 1946-05-31 1956-08-28 Robert E Dillon Antenna
US2867776A (en) * 1954-12-31 1959-01-06 Rca Corp Surface waveguide transition section
US2878470A (en) * 1954-05-27 1959-03-17 Sanders Associates Inc Conical beam antenna system
US2955287A (en) * 1956-12-31 1960-10-04 Tyner Corp Antenna
US2998605A (en) * 1957-07-09 1961-08-29 Hazeltine Research Inc Antenna system
US3015821A (en) * 1957-07-29 1962-01-02 Avien Inc End fire element array
US4516129A (en) * 1982-06-04 1985-05-07 Canadian Patents & Dev. Ltd. Waveguide with dielectric coated flange antenna feed
US4516133A (en) * 1981-09-09 1985-05-07 Japan Radio Company, Limited Antenna element having non-feed conductive loop surrounding radiating element

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS57129506A (en) * 1980-12-22 1982-08-11 Buikutaa Banii Shiriru Antenna

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE678010C (en) * 1932-12-07 1939-06-24 Julius Pintsch Kom Ges Rotatable arrangement for direction finding by means of ultra-short electric waves of centimeter and decimeter length
DE694523C (en) * 1933-02-09 1940-08-02 Julius Pintsch Kom Ges and receiving arrangements
US2283935A (en) * 1938-04-29 1942-05-26 Bell Telephone Labor Inc Transmission, radiation, and reception of electromagnetic waves
US2370053A (en) * 1940-12-31 1945-02-20 Rca Corp Directive antenna system
US2405992A (en) * 1944-01-19 1946-08-20 Bell Telephone Labor Inc Directive antenna system
US2415089A (en) * 1942-05-28 1947-02-04 Bell Telephone Labor Inc Microwave antennas
US2419556A (en) * 1942-07-22 1947-04-29 Bell Telephone Labor Inc Scanning antenna
US2429601A (en) * 1943-11-22 1947-10-28 Bell Telephone Labor Inc Microwave radar directive antenna
US2442951A (en) * 1944-05-27 1948-06-08 Rca Corp System for focusing and for directing radio-frequency energy
US2478241A (en) * 1945-07-09 1949-08-09 Chu Lan Jen Flat beam antenna
US2486589A (en) * 1945-02-27 1949-11-01 Us Navy Apple-core reflector antenna

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE678010C (en) * 1932-12-07 1939-06-24 Julius Pintsch Kom Ges Rotatable arrangement for direction finding by means of ultra-short electric waves of centimeter and decimeter length
DE694523C (en) * 1933-02-09 1940-08-02 Julius Pintsch Kom Ges and receiving arrangements
US2283935A (en) * 1938-04-29 1942-05-26 Bell Telephone Labor Inc Transmission, radiation, and reception of electromagnetic waves
US2370053A (en) * 1940-12-31 1945-02-20 Rca Corp Directive antenna system
US2415089A (en) * 1942-05-28 1947-02-04 Bell Telephone Labor Inc Microwave antennas
US2419556A (en) * 1942-07-22 1947-04-29 Bell Telephone Labor Inc Scanning antenna
US2429601A (en) * 1943-11-22 1947-10-28 Bell Telephone Labor Inc Microwave radar directive antenna
US2405992A (en) * 1944-01-19 1946-08-20 Bell Telephone Labor Inc Directive antenna system
US2442951A (en) * 1944-05-27 1948-06-08 Rca Corp System for focusing and for directing radio-frequency energy
US2486589A (en) * 1945-02-27 1949-11-01 Us Navy Apple-core reflector antenna
US2478241A (en) * 1945-07-09 1949-08-09 Chu Lan Jen Flat beam antenna

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2761139A (en) * 1946-05-31 1956-08-28 Robert E Dillon Antenna
US2677767A (en) * 1949-06-04 1954-05-04 Int Standard Electric Corp Omnidirectional antenna
US2878470A (en) * 1954-05-27 1959-03-17 Sanders Associates Inc Conical beam antenna system
US2867776A (en) * 1954-12-31 1959-01-06 Rca Corp Surface waveguide transition section
US2955287A (en) * 1956-12-31 1960-10-04 Tyner Corp Antenna
US2998605A (en) * 1957-07-09 1961-08-29 Hazeltine Research Inc Antenna system
US3015821A (en) * 1957-07-29 1962-01-02 Avien Inc End fire element array
US4516133A (en) * 1981-09-09 1985-05-07 Japan Radio Company, Limited Antenna element having non-feed conductive loop surrounding radiating element
US4516129A (en) * 1982-06-04 1985-05-07 Canadian Patents & Dev. Ltd. Waveguide with dielectric coated flange antenna feed

Also Published As

Publication number Publication date
GB647136A (en) 1950-12-06

Similar Documents

Publication Publication Date Title
US4772891A (en) Broadband dual polarized radiator for surface wave transmission line
US4042935A (en) Wideband multiplexing antenna feed employing cavity backed wing dipoles
US2588610A (en) Directional antenna system
US3568204A (en) Multimode antenna feed system having a plurality of tracking elements mounted symmetrically about the inner walls and at the aperture end of a scalar horn
US2275646A (en) Antenna
US2754513A (en) Antenna
US2654842A (en) Radio frequency antenna
US2863145A (en) Spiral slot antenna
US2663797A (en) Directive antenna
US3348228A (en) Circular dipole antenna array
US2556046A (en) Directional antenna system
US2611869A (en) Aerial system
US3836977A (en) Antenna system having a reflector with a substantially open construction
US3039099A (en) Linearly polarized spiral antenna system
US3757345A (en) Shielded end-fire antenna
US2820965A (en) Dual polarization antenna
US3268902A (en) Dual frequency microwave aperturetype antenna providing similar radiation pattern on both frequencies
US3032762A (en) Circularly arrayed slot antenna
US2548821A (en) Horn radiator adapted to be fed by a coaxial line
US2486589A (en) Apple-core reflector antenna
US2512137A (en) Antenna
US2726388A (en) Antenna system combinations and arrays
JPH05152832A (en) Nest cuppy-shaped multiple frequency band antenna with notch
US3205499A (en) Dual polarized horn antenna
US2549143A (en) Microwave broadcast antenna