US3308465A - Antenna system - Google Patents

Antenna system Download PDF

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Publication number
US3308465A
US3308465A US283287A US28328763A US3308465A US 3308465 A US3308465 A US 3308465A US 283287 A US283287 A US 283287A US 28328763 A US28328763 A US 28328763A US 3308465 A US3308465 A US 3308465A
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Prior art keywords
arrays
array
radiator
circuits
lobe
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US283287A
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Tamama Tetsuo
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Mitsubishi Electric Corp
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Mitsubishi Electric Corp
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    • 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
    • H01Q3/44—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system varying the electric or magnetic characteristics of reflecting, refracting, or diffracting devices associated with the radiating element
    • H01Q3/46—Active lenses or reflecting arrays
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q25/00—Antennas or antenna systems providing at least two radiating patterns
    • 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
    • H01Q3/26—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture
    • H01Q3/30—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture varying the relative phase between the radiating elements of an array
    • H01Q3/34—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture varying the relative phase between the radiating elements of an array by electrical means

Definitions

  • This invention relates to improvement in antenna systems, and more particularly, to realization of antenna array systems that are capable of electronic beam steering, multi-beaming and beam shaping.
  • an antenna array or an assembly of radiJ ator elements usually of identical characteristics distributed in linear, circular, planar or other alignments, exhibits an overall directivity pattern which is a product of that of each element, known as element pattern, and that inherent to the alignment itself, known as array pattern. It has been further known that this latter pattern can be steered without mechanical motion of any of the elements by introducing suitable amounts of phase difference between signals transmitted by and/ or received from each element.
  • conspicuous side lobes more correctly known as grating lobes, begin to appear; their number and magnitude being aggrandized as the spacing becomes wider. Consequently the element spacing is restricted to be about or less than one-half the wavelength.
  • width of the lobes varies roughly in inverse proportion to the number of radiator elements arrayed.
  • radiator elements required for high angular accuracy can be very large, in some planar array applications the number amounting to tens of thousands.
  • the primary object of the present invention is to provide the means to overcome these disadvantages by realizing an antenna system that has radiation elements disposed at intervals much larger than one-half of the wavelength and yet is unaffected by the undesired effects of grating lobes, employing two or more arrays of different grating lobe distributions and causing only preselected lobes from each array to coincide in direction.
  • Another object of the present invention is to provide the means for simple but effective beam shaping techJ nique, by applying which to an antenna array the shape of the lobes can be made substantially sharper than was formerly possible for a given number of arrayed radiator elements.
  • a lobe designates a protruding portion of antenna or radiator array directivity which may or may not desirably contribute to the transmission and/or reception, while a beam designates a lobe or a set of lobes intentionally selected to perform the desired function of transmission and/or reception.
  • One of the prior arts of multi-beaming known as a defocussed stacked beams technique, requires a paraboloid reflector equipped with a number of primary feed horns located in a row near the reflector focal point, each more defocussed than the last, causing the same number of beams to be radiated each more off the reflector axis than the last, corresponding to the amount of defocus of each feed horn.
  • a further object, then, of the present invention is to provide a simple and effective multi-beaming technique which, when applied to the aforementioned system, allows the number of transmission and reception channels to be held to a minimum number while permitting a very large number of undeteriorated beams to be generated.
  • the array exhibits a maximum directivity in a direction where the energy related to all radiator elements is added in phase.
  • the directivity pattern in the vicinity of this direction is what is commonly referred to as a lobe.
  • the direction p of the nose of the lobe measured from the array broadside is given by x ,t S111 where A is the employed free-space wavelength.
  • At least two radiator arrays are employed, each being given a different value of d/7 ⁇ , so that each array has a multi-lobe directivity of different angular spacing of lo es.
  • Each of said arrays is provided with one or a plurality of circuit means for introducing predetermined phase differences between said elements.
  • Means is provided for combining said arrays through said circuit means whereby a rpreselected lobe of the directivity pattern of one array as produced by the corresponding circuit means coincides in one angular direction with a preselected lobe of each of the directivity pattern(s) of the other array(s) as produced by the corresponding other circuit means, to constitute what will be hereinafter called a main beam.
  • FIG. 1 is a circuit diagram in schematic form of an antenna system in accordance with the present invention, comprising two arrays, each consisting of two parallel-fed radiators;
  • FIG. 2 is a circuit diagram in schematic form of an antenna system in accordance with the present invention, comprising two arrays, each consisting of four series-fed radiators;
  • FIG. 3 is a circuit diagram in schematic form of an antenna system in accordance with the present invention, comprising two arrays, each consisting of two parallelfed radiators, but one radiator thereof is used in common with both arrays;
  • FIG. 4 is a circuit diagram in schematic form of an antenna system equivalent to that of FIG. 3, except that it is used in passive form less transmitter in direction finder application;
  • FIG. 5 is a circuit diagram in schematic form of an antenna system equivalent to that of FIG. 3, except that it utilizes only one radiator in transmission;
  • FIG. 6 is a circuit diagram in schematic form of an antenna system equivalent to that of FIG. 5, except that it is equipped with variable phase shifting means to perform electronic beam steering;
  • FIG. 7 is a circuit diagram in schematic form of an antenna system equivalent to that of FIG. 3, except that it is equipped with means to perform beam shaping;
  • FIG. 8 is a circuit diagram in schematic form of an antenna system equivalent to that of FIG. 3, except that it is equipped with alternate means to perform beam shaping;
  • FIG. 9 is a portion of directivity pattern diagram of an antenna array illustrating the principle of beam shaping in accordance with the present invention.
  • FIG. 10 is a circuit diagram in schematic form of an antenna system equivalent to that of FIG. 5, except that it is equipped with alternate means of multi-beaming.
  • FIG. l there are shown at 10 and 20 two parallel-fed antenna arrays each consisting of two radiators 11 and 12, spaced a distance d1 apart, and 21 and 22, spaced a distance d2 apart, respectively. These distances are not identical in proportion to the employed wavelength, and both are larger in magnitude than one-half thereof.
  • Circuit means a, 30b, 30C and 30d are provided in parallel for the former array 10, each independently to introduce phase shifts in amounts of rpm, 3011 ,blc and wld respectively, between radiators 11 and 12 by means of phase shifting means 31a, 31b, 31C and 31d.
  • circuit means a, 40b, 40C and 40d are provided in parallel for the latter array 20, each independently to introduce phase shifts in amounts of i/fza, 1,0%, #12s, and
  • Each multi-beaming circuit is equipped further with hydrid circuits 50a, 50b, 50c, 50d, 60a, 6017, 60C and 60d respectively, to divide the transmitted energy to and/ or to sum up the received energy from the aforementioned radiators.
  • the energy to be transmitted through these circuits and radiators are supplied by transmitters a, 90b, 90e and 90d, through duplexers 70a, 70b, 70e, 70d, 80a, 8017, 80C and 80d which regulate the proper flow of transmitted and received energies, as indicated by the pointers in the drawing.
  • Each apparatus herefore described should be readily recognizable by those skilled in the art as conventional components of such searching and detecting devices as radars.
  • coincidence gates 10011, b, 100e and 100d the function of which is to close the circuit and yield as its output either one or the other or the sum of both of the two inputs only when both thereof are present
  • power differential gates a, 110b, 110C and 110d the function of which is to close the circuit and yield as its output either one or the other or the sum of both of the two inputs only when both thereof are of the identical power level.
  • the outputs of these gate means rare supplied into switching circuits a, 12017, 120C and 12061', the function of which is to close the circuit and yield to output terminal means a, b, c .and d the inputs from the coincidence gate only when the inputs from the power differential gates are present.
  • Equation 1 the array directivity pattern of the system ⁇ comprising array 10 -and multi-beaming circuit 30a (hereinafter to be referred to as f-pattern at circuit 30a) and that of the system comprising array 20 and multi-beaming circuit 40a are so directed that, of all the lobes therein, only one each, namely the one that corresponds to the 111:0 case of Equation l, has identical bearing while others have not, with the result that any incoming signal covered by this lobe appears at output terminal means a while those covered by other lobes do not.
  • a main beam is generated, constituted by two particular lobes in patterns at circuits 30a and 40a; and it can be readily shown from Equation 1 that this beam (which will hereinafter be referred to as main beam at terminal a) is directed to array broadside.
  • the second main beam at terminal b is generated by patterns at circuits 301: and 40b, except that it is directed to the following angle to the array broadside:
  • Equations 2, 3, 4 and 5 are expressed in one representative form only, it can readily be shown that, if we recall that the phase recurs every 211" radians, they are not so limited, but can be written in a more generalized form, as follows:
  • KM-mimi d1 d2 where m13, mlb, are positive or negative integers.
  • the device illustrated in FIG. l is equipped with apparatus to avoid the above mentioned erroneous operation, the apparatus being coincidence gates ltla, 100b, 100C and 10001; power differential gates lltla, llltlb, 110C and llcz'; and switching circuits 120a, 120b, 120C and 120:1. If two incoming signals are present and are so located as to cause the aforementioned erroneous operation, and if their sources are at different distances from the device, those signals will not pass through the coincidence gates, their time of arrival at the gates being non-coincidental; their appearance at the output terminal means is thereby avoided.
  • the device illustrated in FIG. l thus, is capable of detecting adequately incoming signal bearings virtually in every foreseeable occasion.
  • FIG. 2 One such possible modification is illustrated in FIG. 2, referring to which, there are shown at 10 and 20 two series-fed antenna arrays each consisting of four radiators 11, 12, 13 and 14, spaced a distance d1 apart from each other, and 21, 22, 23 and 24, spaced a distance d2 apart from each other, respectively.
  • hybrid circuits 51 through 54, SSab through 58ab, 55cd thro-ugh 58cd; 461 through 64, 65ab through 68ab and 65ml through 68nd are used to connect arrays to multi-beaming circuits 30a, 30b, 30e, 30d; 40a, 40h, 40e and 40d, and that certain components corresponding to those of FIG. l, namely duplexers, transmitters, coincidence gates, power differential gates and switching circuits are represented as single blocks 130g, 130b, 130e ⁇ and 130d.
  • FIGS. 3 through 6 Several other forms of possible modifications are illustrated in FIGS. 3 through 6, each of which will be briefly described.
  • FIG. 3 illustrates a modification of FIG. 1, in which radiators 11 and 21 are incorporated into single element 11 which is used in common with both arrays 10 and 20, and which is advantageous in that the number of required radiator elements are reduced from four to three Without seriously affecting the system performance.
  • FIG. 4 illustrates a modification of FIG. 3, in which duplexers 70a, 70b, 80a, 80b, and transmitters a, 90b, are eliminated, and which is still capable of detecting incoming signal bearing, and which is suitable for passive direction finding application.
  • FIG. 5 illustrates a modification of FIG. 3, in which duplexers 70a, 70b, 80a, 8012, and transmitters 90a, 90b, are eliminated, instead of which a single duplexer 70 and a transmitter 90 are installed directly behind the radiator element 11; this arrangement is advantageous in that the multi-beaming circuits 30a, 30b, 40a, 40h, and components thereof are not required to withstand the high-power transmission energy.
  • FIG. 6 illustrates a modification of FIG. 5, in which phase differences between the radiator elements are variable through the use of variable phase shifting means 34 and 44, by sweeping the phase shift of which the cluster of main beams can be electronically steered en masse, with the advantage of increased system flexibility.
  • FIG. 7 illustrates a device largely similar to that of FIG. 3 but is equipped with beam shaping means which utilize the above phenomenon.
  • a comparable beam shaping effect can be achieved by utilizing beam ⁇ shaping circuits of slightly different function, namely ysuch circuits as to yield on their output terminal means G a signal proportional to the ratio E/F of two inputs E and F only when the said quotient exceeds a preselected threshold level.
  • phase shifting means 31a, 31b, and 4ta, 411 While it has been assumed that required amounts of phase shifts for multi-beaming and beam steering are introduced by phase shifting means 31a, 31b, and 4ta, 411;, in FIGS. l through 8 and 34 and 44 in FIGURE 6, it is not necessarily the most desirable procedure to introduce such phase shifts directly to the signal from each of the radiator elements, in view of the possible insertion Joss and ⁇ structural clum-siness of such means as ferrite phase Shifters. An alternate means of introducing such phase shifts without the above disadvantages will now be described.
  • FIG. 10 illustrates a device largely similar to that of FIG. 5 except that the phase ⁇ shifting means 31a, 31b,
  • a llocal oscillator 190 feeds into each of said mixers a set of waves that retain among them phase relationship identical to those required to multi-beaming lpreviously specified in relation to Equations 2 through 5, for example.
  • the fu-rther elaboration on the -theory of operation of the device of FIG. 10 will now be superfluous, as it is quite ⁇ similar to that described in connection with FIGS. l through 6.
  • An antenna system comprising two or more radiator arrays disposed in parallel with a single plane and each having inter-element ⁇ spacings much larger than one-half of the employed wavelength and multi-lobe array directivity of different angular spacing of lobes; means independently -to displace angularly the directivity of each of said arrays by introducing suitable amounts of inter-element phase differences in a manner that one and only one lobe from each of said arrays coincides with e-ach other in direction; ⁇ and means to combine the received signal outputs from each of said arrays in a manner that only -such signal as is received from all of said arrays is yielded as its output.
  • An antenna system comprising two or more radiator arrays each consisting of an even number of radiator elements spaced at inter-element spacings of larger than onehalf of the employed wavelength and having multi-l0be array directivity of different angular spacing of lobes; means independently to displace angularly the directivity of each of said arrays by introducing suitable amounts of inter-element phase differences in a manner that one and only one lobe from each of said arrays coincides each other in direction; means connected to each of said arrays to yield as output of the corresponding array a signal that attains its maximum magnitude when either the difference of the received signal from one half of the radiator ele- -rnents of said array and that from another half of the radiator elements thereof is below a preselected threshold level, or the ratio of the sum of the received signal from each radiator element of said array to the difference of the received signa-l from one half of the radiator elements thereof and that from another half of the radiator elements thereof exceeds a preselected threshold level, provided either the sum of the received signal from each radiator
  • An antenna system comprising two or more radiator arrays each having inter-element spacings of :larger than one-half of the employed wavelength and multi-lobe array directivity of ditferent angular spacing of lobes; the means independently to displace angularly the dire-ctivity of each of said arrays by introducing -suitable amounts of interelement phase differences in a manner that one and only one lobe from each of said arrays coincides each other in direction; and the means to combine the received signal outputs of each of said arrays in a manner that only such signal as received from all of said arrays simultaneously and at approximately identical power level is yielded as its output.
  • An antenna system comprising two or more radiator arrays each consisting of an even number of radiator elements spaced at inter-element spacings of larger than onehalf of the employed wavelength and having multi-lobe array directivity of different angular spacing of lobes; means independently to displace angularly the directivity of each of said arrays by introd-ucing suitable amounts of inter-element phase differences in a manner that one and only one lobe from each of said arrays coincides each other in direction; means connected to each of said arrays to yield as output of the corresponding array a signal that attains its maximum magnitude when either the difference of received signal of one half of the radiator elements of said array and that of another half of the radiator elements thereof is below a preselected threshold level, or the ratio f the sum of the received signal of each radiator element of said array to the difference of the received signal of one half of the radiator elements thereof and that of another half of the radiator elements thereof exceeds a preselected threshold level, provided either the sum of the received signal of each radiator element of said array or received signal from
  • An antenna system comprising two or more radiator arrays each having inter-element spacings of larger than one-half of the employed wavelength and multi-lobe array directivity of different angular spacing of lobes; a plurality of circuits connected in parallel to each of said arrays, each of said circuits having the means independently to displace angularly the directivity of each of said arrays by introducing suitable amounts of inter-element phase differences; and means to combine the received signal outputs from said arrays through said circuits so that one circuit output per array is combined in a manner that one and only one lobe from each of said arrays coincides each other in direction, the circuits being so provided and the combinations so chosen that the directions of said directionally coinciding lobes 4be unique and unduplicated for each combination of said circuits, so that each of said combinat-ions yields as its output only such signal as received from all of said arrays.
  • An antenna system comprising two or more radiator arrays each consisting of an even number of radiator elements spaced at inter-element spacings of larger than onehalf of the employed wavelength and having multi-lobe array directivity of different angular spacing of lobes; a plurality of circuits connected in parallel to each of said arrays, each of said circuits having the means independently to displace angularly the directivity of each of said arrays by introducing suitable amounts of inter-element phase differences; means connected to each of said circuits to yield as output of the corresponding circuit a signal that attains its maximum magnitude when either the difference of the received signal from one half of the radiator elements of corresponding array and that from another half of the radiator elements thereof is below a preselected threshold level, or the ratio of the sum of the received signal from each radiator element of said array to the difference of the received signal from one half of the radiator elements thereof and that from another half of the radiator elements thereof exceeds a preselected threshold level, provided either the sum of the received signal from each radiator element of said array or received signal from any one of
  • circuits being so provided and the combinations so chosen that the directions of said directionally coinciding lobes be unique and unduplicated for each combination of said circuits, so that each of said combinations yields as its output only such signal as received from all of said arrays.
  • An antenna system comprising two or more radiator arrays each having inter-element spacings ⁇ of larger than one-half of the employed wavelength and multi-lobe array directivity of different angular spacing of lobes; a plurality of circuits connected in parallel to each of said arrays, each of said circuits having the means independently to displace angularly the directivity of each of said arrays by introducing suitable amounts of inter-element phase differences; and means to combine the received signal outputs from said arrays through said circuits so that one circuit output per array is combined in a manner that one and only one lobe from each of said arrays coincides each other in direction, the circuits being so provided and the combinations so chosen that the directions of said directionally coinciding lobes be unique and unduplicated for each combination of said circuits, so that each of said combinations yields as its output only such signal as received from all of said arrays simultaneously and at approximately identical power level.
  • An antenna system comprising two or more radiator arrays each consisting of an even number of radiator elements spaced at inter-element spacings of larger than onehalf of the employed wavelength and having multi-lobe array directivity of different angular spacing of lobes; a plurality of circuits connected in parallel to each of said arrays, each of said circuits having the means independently to displace angularly the directivity of each of said arrays by introducing suitable amounts of inter-element phase differences; means connected to each of said circuits to yield as output of the corresponding circuit a signal that attains its maximum magnitude when either the difference of the received signal from one half of the radiator elements of corresponding array and that from another half of the radiator elements thereof is below a preselected threshold level, or the ratio of the sunt of the received signal from each radiator element of said array to the difference of the received signal from one half of the radiator elements thereof and that from another half of the radiator elements thereof exceeds a preselected threshold level, provided either the sum of the received signal from each radiator element of said array or received signal from any one of

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Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3422438A (en) * 1965-11-30 1969-01-14 Arthur E Marston Conjugate pair feed system for antenna array
US3434139A (en) * 1965-07-15 1969-03-18 North American Rockwell Frequency-controlled scanning monopulse antenna
US3510871A (en) * 1967-07-12 1970-05-05 Mitsubishi Electric Corp Radio detection apparatus
US3518695A (en) * 1967-09-07 1970-06-30 Collins Radio Co Antenna array multifrequency and beam steering control multiplex feed
US4544925A (en) * 1981-08-07 1985-10-01 Thomson-Csf Assembly of main and auxiliary electronic scanning antennas and radar incorporating such an assembly
US4721960A (en) * 1986-07-15 1988-01-26 Canadian Marconi Company Beam forming antenna system
US4724441A (en) * 1986-05-23 1988-02-09 Ball Corporation Transmit/receive module for phased array antenna system
US5745084A (en) * 1994-06-17 1998-04-28 Lusignan; Bruce B. Very small aperture terminal & antenna for use therein
US5797082A (en) * 1994-06-17 1998-08-18 Terrastar, Inc. Communication receiver for receiving satellite broadcasts
WO2023245274A1 (en) * 2022-06-22 2023-12-28 Huawei Technologies Canada Co., Ltd. Tightly-coupled antenna array and method thereof

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2727980A1 (de) * 1977-06-22 1979-01-18 Licentia Gmbh Antennensystem mit gruppenweise zusammengeschalteten einzelantennen

Citations (2)

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Publication number Priority date Publication date Assignee Title
US2245660A (en) * 1938-10-12 1941-06-17 Bell Telephone Labor Inc Radio system
US3255450A (en) * 1960-06-15 1966-06-07 Sanders Associates Inc Multiple beam antenna system employing multiple directional couplers in the leadin

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2245660A (en) * 1938-10-12 1941-06-17 Bell Telephone Labor Inc Radio system
US3255450A (en) * 1960-06-15 1966-06-07 Sanders Associates Inc Multiple beam antenna system employing multiple directional couplers in the leadin

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3434139A (en) * 1965-07-15 1969-03-18 North American Rockwell Frequency-controlled scanning monopulse antenna
US3422438A (en) * 1965-11-30 1969-01-14 Arthur E Marston Conjugate pair feed system for antenna array
US3510871A (en) * 1967-07-12 1970-05-05 Mitsubishi Electric Corp Radio detection apparatus
US3518695A (en) * 1967-09-07 1970-06-30 Collins Radio Co Antenna array multifrequency and beam steering control multiplex feed
US4544925A (en) * 1981-08-07 1985-10-01 Thomson-Csf Assembly of main and auxiliary electronic scanning antennas and radar incorporating such an assembly
US4724441A (en) * 1986-05-23 1988-02-09 Ball Corporation Transmit/receive module for phased array antenna system
US4721960A (en) * 1986-07-15 1988-01-26 Canadian Marconi Company Beam forming antenna system
US5745084A (en) * 1994-06-17 1998-04-28 Lusignan; Bruce B. Very small aperture terminal & antenna for use therein
US5797082A (en) * 1994-06-17 1998-08-18 Terrastar, Inc. Communication receiver for receiving satellite broadcasts
US5913151A (en) * 1994-06-17 1999-06-15 Terrastar, Inc. Small antenna for receiving signals from constellation of satellites in close geosynchronous orbit
US5930680A (en) * 1994-06-17 1999-07-27 Terrastar, Inc. Method and system for transceiving signals using a constellation of satellites in close geosynchronous orbit
US6075969A (en) * 1994-06-17 2000-06-13 Terrastar, Inc. Method for receiving signals from a constellation of satellites in close geosynchronous orbit
WO2023245274A1 (en) * 2022-06-22 2023-12-28 Huawei Technologies Canada Co., Ltd. Tightly-coupled antenna array and method thereof

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DE1791252B2 (de) 1973-08-16
DE1791252C3 (de) 1974-03-14
GB1051038A (xx)
DE1441757A1 (de) 1968-10-31
DE1791252A1 (de) 1972-04-20

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