US3122745A - Reflection antenna employing multiple director elements and multiple reflection of energy to effect increased gain - Google Patents

Reflection antenna employing multiple director elements and multiple reflection of energy to effect increased gain Download PDF

Info

Publication number
US3122745A
US3122745A US812565A US81256559A US3122745A US 3122745 A US3122745 A US 3122745A US 812565 A US812565 A US 812565A US 81256559 A US81256559 A US 81256559A US 3122745 A US3122745 A US 3122745A
Authority
US
United States
Prior art keywords
antenna
gain
reflection
energy
array
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
US812565A
Other languages
English (en)
Inventor
Hermann W Ehrenspeck
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.)
Individual
Original Assignee
Individual
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
Priority to NL251575D priority Critical patent/NL251575A/xx
Application filed by Individual filed Critical Individual
Priority to US812565A priority patent/US3122745A/en
Priority to GB16689/60A priority patent/GB938572A/en
Priority to DE1960K0040687 priority patent/DE1167920B/de
Priority to FR827234A priority patent/FR1262089A/fr
Application granted granted Critical
Publication of US3122745A publication Critical patent/US3122745A/en
Priority to DE1965E0028673 priority patent/DE1293257B/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • 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
    • H01Q19/18—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 having two or more spaced reflecting surfaces
    • H01Q19/185—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 having two or more spaced reflecting surfaces wherein the surfaces are plane
    • 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
    • H01Q19/28—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 a secondary device in the form of two or more substantially straight conductive elements
    • H01Q19/30—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 a secondary device in the form of two or more substantially straight conductive elements the primary active element being centre-fed and substantially straight, e.g. Yagi antenna

Definitions

  • This invention relates generally to directional antennas and more particularly to a modification of slow wave antennas to produce a reflection of energy from an array to cause it to traverse the array at least once before it is radiated and thereby increase gain.
  • the gain of slow wave antennas depends on the phase velocity of the surface wave travelling along it and the length of the antenna; however, for a given length there is an optimum phase velocity beyond which the gain decreases, therefore, for adjustment of antennas at optimum phase velocity, the gain becomes proportional to the antenna length.
  • Another object of this invention involves the provision of a novel endfire array arrangement that allows sharp narrow beam-width patterns with reduced sidelobes.
  • Still another object of this invention involves the provision of an antenna utilizable at high or low frequencies.
  • a further object of this invention involves the provision of an antenna suitable for flush mounting.
  • a still further object of this invention involves the construction of a novel endflre antenna of currently available material that lend themselves to standard mass production manufacturing techniques and of less cost than antennas of similar gain.
  • FIGURE 1 is a schematic representation of a conventional endfire antenna with the main lobe of its pattern
  • FIGURE 2 is a schematic representation of the backfire antenna embodiment of my invention with the main lobe of its pattern
  • FIGURE 3 is a schematic representation of the embodiment of FIGURE 2 adapted for flush mounting
  • FIGURE 4 is a schematic representation of a multiple reflection endfire antenna embodiment with the main lobe of its pattern.
  • a conventional endfire Yagi antenna is shown wherein the feed F at one end excites the array and the energy travels along the array by means of directors D with a phase velocity slower than that of light. Apart from a negligible amount radiated directly from the feeder F, the energy is radiated from a virtual aperture (shown in dashed lines) located at the termination of the array.
  • the concept of the virtual aperture is more fully explained in my copending application Serial No. 719,698, flied March 6, 1958, titled Endfire Array, wherein the virtual aperture at the end of an array includes the field at which power levels are from maximum to 26 db below maximum.
  • a linear reflector R is mounted behind the feeder, as shown in FIGURE 1, to increase the gain in the forward direction.
  • the energy travels along the array in the direction of the arrows and radiates with the pattern (sidelobes omitted) indicated.
  • the phase front of a traveling wave lies substantially in a plane at the radiating end of an endfire array when the antenna is adjusted for optimum gain in the forward direction.
  • the concept of this invention embodied in the representation labeled FIGURE 2, allows the traveling wave to impinge on and be reflected by a planar reflector M such that the wave now travels along the array for a second time in the direction toward the feed.
  • the array of FIGURE 1 as modified by the use of this invention as shown in FlGURE 2 utilizes a feed F, a reflector ll, directors D, and has a virtual aperture V.
  • the waves impinging on the reflector in this case are not slow waves since the usual position is behind the feed.
  • the mirror action of reflector M since there is no direct wave with which to interfere as in the linear antenna case, and since it is situated in the main wave channel of a slow wave structure to reflect the slow wave energy, causes all the energy in the channel to retravel along the wray thus creating a large increase in gain.
  • This increase in gain is explainable by the fact that the retravel makes the antenna act like one double its length. In FlGURE 2 the gain would be at least equal to a factor of two, except that reflector R may tend to reduce the gain factor slightly.
  • FIGURE 3 is an example of the flush mounting of the antenna of FIGURE 2.
  • the feed F in this application is enclosed in a hollow tube T which supports the array and its elements and feeds the feeder elements which are insulated from tube T.
  • the backfire antennas of FIGURES 2 and 3 radiate in a direction reverse from normal with an eflective length of double and a gain increase of at least 3 db above a conventional endflre array.
  • a modification of the backfire antenna allows for further gain increases by utilizing multiple reflection.
  • the multiple reflection concept is embodied in the schematic representation of FIGURE 4 where a feed F feeds an array of directors D in front or which is placed a partial reflector R, While a reflector M is placed behind the feed, as shown.
  • This structure modifies the principle of the backfire antenna in that only a part of the energy travelling along the antenna from the feed end to the output end is reflected by reflector R while the remainder is radiated in the normal endfire direction.
  • the reflected portion of the energy travels a second time along the antenna but in the opposite direction until it impinges upon its feed reflector M.
  • M is a planar reflector which must be of such size as to reflect back as much of the surface wave energy possible and for maximum gain is of the same size as the virtual aperture.
  • the energy then travels a third time along the antenna; this time in the normal endflre direction. After reaching the antenna end it is again partly radiated at the virtual aperture V and partly reflected back, as before. This process continues until all the energy has been radiated.
  • Maximum gain of the multiple reflection antenna with a mirror reflector M of the same size as the virtual aperture requires optimization of two parameters: the reflectivity of the partial reflector R at the radiating end, and the phase velocity along the antenna which is accomplished by adjustment of the length of directors D in ac- Qordance with the new effective length of the antenna.
  • the multiple reflection antenna has greater structural simplicity and strength since the feed is located at the same end as the reflector plane.
  • the partial reflector R or the planar reflector M may be of solid metal, metalized plastic, screening material, or of closely spaced rods either parallel or radially mounted.
  • the individual elements D are decreased from the optimum value for a conventional endfire antenna for phase adjustment.
  • the multiple reflection principle may be applied to the backfire antenna to increase its gain by utilizing a partial reflector rather than a linear reflector in order to cause a partial reflection back along the array in accordance with the action described relative to FTGURE 4.
  • Means for increasing the gain and decreasing the side lobes of a multiple director type of antenna array comprising a planar reflector positioned at what would normally be the emitting end of the series of director ele- I ments, for reflecting energy back along said director elements in reverse sequence, for emission at the end of said array Where the energy traverse began.

Landscapes

  • Aerials With Secondary Devices (AREA)
US812565A 1959-05-11 1959-05-11 Reflection antenna employing multiple director elements and multiple reflection of energy to effect increased gain Expired - Lifetime US3122745A (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
NL251575D NL251575A (de) 1959-05-11
US812565A US3122745A (en) 1959-05-11 1959-05-11 Reflection antenna employing multiple director elements and multiple reflection of energy to effect increased gain
GB16689/60A GB938572A (en) 1959-05-11 1960-05-11 Improvements in and relating to directional aerial array
DE1960K0040687 DE1167920B (de) 1959-05-11 1960-05-12 Verfahren zur Erhoehung des Antennengewinnes von Oberflaechenwellenantennen und Oberflaechenwellenantennen zur Durchfuehrung des Verfahrens
FR827234A FR1262089A (fr) 1959-05-11 1960-05-14 Antenne de réflexion et procédé pour augmenter le gain d'une antenne à onde lente
DE1965E0028673 DE1293257B (de) 1959-05-11 1965-02-11 Oberflaechenwellenantenne mit einem Reflektor und einer Reflektorflaeche

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US812565A US3122745A (en) 1959-05-11 1959-05-11 Reflection antenna employing multiple director elements and multiple reflection of energy to effect increased gain

Publications (1)

Publication Number Publication Date
US3122745A true US3122745A (en) 1964-02-25

Family

ID=25209985

Family Applications (1)

Application Number Title Priority Date Filing Date
US812565A Expired - Lifetime US3122745A (en) 1959-05-11 1959-05-11 Reflection antenna employing multiple director elements and multiple reflection of energy to effect increased gain

Country Status (4)

Country Link
US (1) US3122745A (de)
DE (1) DE1167920B (de)
GB (1) GB938572A (de)
NL (1) NL251575A (de)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3774223A (en) * 1972-10-04 1973-11-20 Us Air Force High-frequency waveguide feed in combination with a short-backfire antenna
US5600339A (en) * 1994-12-06 1997-02-04 Oros; Edward A. Antenna
US20090267850A1 (en) * 2008-04-28 2009-10-29 Harris Corporation Circularly polarized loop reflector antenna and associated methods
US20150207216A1 (en) * 2013-06-04 2015-07-23 Panasonic Intellectual Property Management Co., Ltd. Wireless module
US20220352620A1 (en) * 2020-02-03 2022-11-03 AGC Inc. Antenna device

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2627028A (en) * 1945-07-03 1953-01-27 Welville B Nowak Antenna system
GB741897A (en) * 1953-06-17 1955-12-14 Marconi Wireless Telegraph Co Improvements in or relating to directional aerial systems
US2822536A (en) * 1954-12-31 1958-02-04 Itt Meteorological radar
US2841792A (en) * 1951-12-29 1958-07-01 Bell Telephone Labor Inc Directional array employing laminated conductor

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2627028A (en) * 1945-07-03 1953-01-27 Welville B Nowak Antenna system
US2841792A (en) * 1951-12-29 1958-07-01 Bell Telephone Labor Inc Directional array employing laminated conductor
GB741897A (en) * 1953-06-17 1955-12-14 Marconi Wireless Telegraph Co Improvements in or relating to directional aerial systems
US2822536A (en) * 1954-12-31 1958-02-04 Itt Meteorological radar

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3774223A (en) * 1972-10-04 1973-11-20 Us Air Force High-frequency waveguide feed in combination with a short-backfire antenna
US5600339A (en) * 1994-12-06 1997-02-04 Oros; Edward A. Antenna
US20090267850A1 (en) * 2008-04-28 2009-10-29 Harris Corporation Circularly polarized loop reflector antenna and associated methods
US8368608B2 (en) 2008-04-28 2013-02-05 Harris Corporation Circularly polarized loop reflector antenna and associated methods
US20150207216A1 (en) * 2013-06-04 2015-07-23 Panasonic Intellectual Property Management Co., Ltd. Wireless module
US20220352620A1 (en) * 2020-02-03 2022-11-03 AGC Inc. Antenna device

Also Published As

Publication number Publication date
DE1167920B (de) 1964-04-16
GB938572A (en) 1963-10-02
NL251575A (de) 1964-02-25

Similar Documents

Publication Publication Date Title
US3414903A (en) Antenna system with dielectric horn structure interposed between the source and lens
US3755815A (en) Phased array fed lens antenna
US2423648A (en) Antenna
US3231892A (en) Antenna feed system simultaneously operable at two frequencies utilizing polarization independent frequency selective intermediate reflector
US2929065A (en) Surface wave antenna
US2370053A (en) Directive antenna system
US3394378A (en) Multiple reflector multiple frequency band antenna system
US3096519A (en) Composite reflector for two independent orthogonally polarized beams
US3995275A (en) Reflector antenna having main and subreflector of diverse curvature
US3045237A (en) Antenna system having beam control members consisting of array of spiral elements
US2822541A (en) Lens antenna system
US3430244A (en) Reflector antennas
US3936837A (en) Corrugated horn fed offset paraboloidal reflector
JP2001060825A (ja) セルラー通信システム用のマルチビーム衛星アンテナ
US3276022A (en) Dual frequency gregorian-newtonian antenna system with newtonian feed located at common focus of parabolic main dish and ellipsoidal sub-dish
US3445850A (en) Dual frequency antenna employing parabolic reflector
US3176301A (en) Plural horns at focus of parabolic reflector with shields to reduce spillover and side lobes
US3122745A (en) Reflection antenna employing multiple director elements and multiple reflection of energy to effect increased gain
US4982198A (en) High performance dipole feed for reflector antennas
US4005433A (en) Small wavelength high efficiency antenna
CN110739547B (zh) 一种卡塞格伦天线
US3696436A (en) Cassegrain antenna with absorber to reduce back radiation
US7119754B2 (en) Receiving antenna for multibeam coverage
USRE26448E (en) Multiple reflection of energy to effect increased gain
US3212095A (en) Low side lobe pillbox antenna employing open-ended baffles