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Publication numberUS2192532 A
Publication typeGrant
Publication dateMar 5, 1940
Filing dateFeb 3, 1936
Priority dateFeb 3, 1936
Publication numberUS 2192532 A, US 2192532A, US-A-2192532, US2192532 A, US2192532A
InventorsMartin Katzin
Original AssigneeRca Corp
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Directive antenna
US 2192532 A
Abstract  available in
Images(1)
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Claims  available in
Description  (OCR text may contain errors)

Patented Mar. 5, 1940 DIRECTIVE ANTENNA Martin Katzin, Riverhead, N. Y., assig nor to Radio Corporation of America, a corporation of.Dela' ware Application February 3, 1936, Serial No- 62,014

11 Claims.

This invention relates to directive antennas and more particularly to directive receiving antennas of the so-called fishbone array.

The directive ffishbone receiving array now used in commercial radio reception consists of a number of parallel, equally spaced, similar size collector wires or doublets connected through small coupling capacitors to a common transmission line which conducts the signal to the radio receiver. The length of the collector wires and the size of the coupling condensers are chosen to give maximum received signal for a desired band of frequencies. Such an arrangement is described in U. S. Patent No. 1,821,402, granted September 1, 1931, to Harold 0. Peterson. It has been found, however, that this antenna array responds rather markedly to only a relatively small frequency band, so that it is necessary to use several arrays to effectively cover the commercial frequency spectrum.

The present invention provides an improved directive antenna in the form of a fishbone array which gives more uniform response over a wide frequency band and thus makes it possibleto efiiciently receive over a much wider frequency spectrum, so that for a given frequency range to be covered, a smaller number of antenna arrays will be required.

A better understanding of the present invention may be had by referring to the following detailed description which is accompanied by drawing wherein:

Fig. 1 illustrates a known type of antenna in the form of a so-called fishbone array;

Fig. 2 is a graph showing curves explanatory of the operation of Fig. l;

Figs. 3a, 3b, 3c and 3d illustrate four different embodiments of the present invention; and

Fig. 4 is a graph showing curves explanatory of the operation of the antennas of the invention.

Referring to Fig. 1, there is shown a directive antenna of known type comprising a two wire transmission line TL to which are coupled transverse doublets I. The wires of transmission line 5 TL are closely spaced in order to avoid their picking up received energy. One terminal of the transmission line is connected to suitable high frequency apparatus, herein indicated conventionally in box'form by thedesignation radio receiver. To make the antenna unilateral in directivity, the end of the line TL nearest the desired transmitting station and farthest removed from the radio receiver is closed by a suitable terminating resistance R. whose impedance is equal I to the surge impedance of the line as loaded by energy collecting doublets I. Resistance R absorbs energy approaching from. the direction of the radio receiver and thereby prevents its reflection back to'the receiver.

' The energy collecting doublets l are preferably .untuned and coupled externally to the feeder members through limiting impedances, herein shown preferably in the form of small series condensers l. United States Patent No. 1,908,536 describes a type of coupling condenser commonly used in this type of antenna. By loosely coupling the doublets to the transmission line TL in this manner, they have less effect upon the velocity of the wave in the-line, and their effect remains small in spite of appreciably large variations in the length of the received waves. Since this type of antenna is well-known in the art, no further description isherein. deemed necessary, except perhaps to refer to United States Patent No. 1,821,402, supra, which describes suchan arrangement'.

Fig. 2 shows various graphs illustrating frequency versus effective height characteristics of an antenna of the type shown in Fig. 1. Graph a is the frequency responsecurve for a fishbone antenna having one particular length of doublet 2 wire and value of coupling condenser. Graph 1) shows a similar frequency response curve for a shorter length of doublet, and graph 0 represents a frequency response curve for a still shorter length of doublet.

Referring to Fig. 3awhich illustrates one embodiment of the present invention, there are shown two sets of doublets It and II having different lengths,; all capacity coupled to the line 'I'Lin the same manner as shown in Fig. 1. The doublets l0 and H, it will be observed, are grouped together in two different lengths.

Fig. 3b shows another embodiment of the invention which is quite similar to the system of f Fig. 3a except that there are here'shown a fishso I bone array having groups of doublets of three' different lengths, namely I, t'and 9. In this embodiment doublets 9 contribute the greater por -tion of the energy at the lower frequencies, doublets 8 at intermediate frequencies and doublets l at the higher frequencies. Now, at the higher frequencies where doublets 1 are contributing the greater portion of the signal energy doublets 9 may load the transmission line TL quite heavily. Therefore, it is advantageous to place these doublets ahead'of doublet Tl so that the useful signal energy passing from 1 to the transmission line andthence to the'receiver is not absorbed by the loading of doublets 9.

Fig. 30 illustrates a still further embodiment of the invention wherein there is employed a tapered array comprising doublets which taper continuously in length from one end of the antenna to the other.

In Fig. 3d, which illustrates a further embodiment, the spacings between adjacent doublets along the transmission line TL are made greater for the longer doublets l2 than for the shorter ones l3. In this manner there is obtained roughly the same number of doublets per wavelength along the transmission line of the mean operating frequency for those doublets in each group.

Reverting for a moment tothe graphs of Fig. 2, it will be evident that each group of collector doublets of a particular length will respond most efiiciently to its corresponding band of frequencies, so that the combination of two or more of such groups, as represented by curves a, b and 0, will give the result of high response for a wider frequency band.

Figs-3d, 3b and 3c employ this principle and give the result of high response for a wider frequency band, as shown in the two curves a and b of Fig. 4, which represent respectively the arrangements of Figs. 3a and 3b. The use of a tapered array such as shown in Fig. 30 results in a more uniform response over the desired frequency spectrum.

The capacitors through which the doublets of Figs. 3a, 3b, 3c and 3d are coupled to line TL need not be all of equal capacitance but rather the capacitance should be properly proportioned for each length of doublet to give optimum transfer of voltage to the line TL without imposing adverse loading. The method of selecting the desired value of capacitance is well known in the art.

It is to be distinctly understood that the present invention is not limited to the precise arrangements shown and described since various modifications may be made without departing from the and scope of the invention. It should also be understood that although the invention has been described particularly with reference to a receiving system, it is not limited thereto since the antenna may equally Well he used for transmitting purposes. Although the doublets have been shown capacitively coupledto the transmission line TL, it should be understood that the fishbone type of array is not limited to such manner of coupling, since the doublets may, if desired, be alternatively connected either resistively or directly to the line TL in the same manner as described in United States Patent No. 1,841,402, supra, and the present invention is applicable toany of these or other types of fishbone antennae wherein any desired type of coupling is used between doublets and line.

What is claimed is:

l. A directive receiving antenna comprising a transmission line, high frequency apparatus coupled to said line, and a plurality of transverse relatively closely spaced aerial elements of different lengths loosely coupled to said line for enabling communication with waves over a relatively wide frequency band, said antenna being aperiodic for Waves of all frequencies in said band. V

2. A directive receiving antenna capable of receiving a wide band of frequencies comprising a straight two wire transmission line, a plurality of relatively closely spaced doublets of different lengths externally and loosely coupled to said line transversely, each doublet having two arms which are coupled to different wires of said line, and high frequency apparatus coupled to one end of said line, said antenna being aperiodic for waves of all frequencies in said band.

end at which said resistance is located toward said high frequency apparatus, said antenna being aperiodic for waves of all frequencies in said band.

4. A directive antenna comprising a transmis sion line, high frequency apparatus coupled to said line, and a plurality of transverse aerial elements of different lengths coupled to said line for enabling communication With waves over a relatively wide frequency band, each of said aerial elements comprising a pair of arms capacitively coupled externally to said line, there being a group of aerial elements for each different length, said antenna being aperiodic for waves of all frequencies in said band.

5. A directive antenna for communication over a band of frequencies comprising a transmission line, high frequency apparatus coupled to said line, and a plurality of relatively closely spaced aerial elements continuously decreasing in length towardsaid high frequency apparatus, said elements-being loosely coupled to said line, said antenna being aperiodic for waves of all frequencies in said band. I

6. A directive receiving antenna capable of re ceiving a wide band offrequencies comprising a relatively closely spaced straight two wire transmission line, a plurality of energy pick-up doublets coupled transversely and externally to said line, each doublet having two arms which are coupled capacitively to different wires of said line, high frequency apparatus coupled to one end of said line and a damping resistance coupled to the other end of said line, said doublets being divided into groups having different lengths of conductors, said antenna being aperiodic for waves of all frequencies in said band.

7. A directive receiving antenna comprising a transmission line, high frequency apparatus coupled to said line, and a plurality of aerial elements, all of different lengths, continuously tapering in length from one end of said antenna to the other and coupled capacitively to said line, the longest aerial element being located farthest from said high frequency apparatus, said antenna being aperiodic over a wide band of frequencies.

8. A directive antenna comprising a straight transmission line, high frequency apparatus coupled to said line, and a plurality of transverse relatively closely spaced aerial elements of different lengths loosely coupled to said line for enabling communication with waves over a relatively wide frequency band, said antenna being aperiodic for waves of all frequencies in said band.

9. A directive antenna comprising a transmis sion line, high frequency apparatus coupled to said line, and a plurality of relatively closely spaced aerial elements of different lengths coupled 75 to said line through limiting impedances for enabling communication with waves over a relatively wide frequency band, said antenna being aperiodic for Waves of all frequencies in said band.

10. A directive antenna comprising a transmission line, high frequency translating apparatus coupled to said line at one end, and three groups of transverse aerial elements of different lengths coupled to said line along the length thereof for enabling communication with waves over a relatively wide frequency band, the aerial elements in each group being of the same length, each of said aerial elements comprising a doublet having a pair of arms capacitively coupled externally to said line, said doublets increasing in size from the end of the line to which the translating apparatus is coupled, said antenna being aperiodic for waves of all frequencies in said band.

11. A directive antenna comprising a' transmission line, high frequency apparatus coupled to said line, and a plurality of groups of aerial elements of different lengths coupled to said line along the length thereof, the spacings between adjacent elements for the longer elements being greater than for the shorter elements, said antenna being aperiodic over a wide band of frequencies.

MAR'II KATZIN.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2580798 *May 22, 1947Jan 1, 1952Muriel KolsterBroad-band antenna system
US2644091 *Feb 26, 1953Jun 30, 1953Middlemark Marvin PHigh-frequency antenna
US2688732 *May 5, 1949Sep 7, 1954Bell Telephone Labor IncWave guide
US2904645 *Sep 17, 1956Sep 15, 1959George A SarlesHelmet radios including a transistor amplifier
US2985879 *Jul 9, 1958May 23, 1961Univ IllinoisFrequency independent antennas
US3011168 *Oct 20, 1958Nov 28, 1961Univ IllinoisFrequency independent unidirectional antenna
US3035266 *May 23, 1958May 15, 1962Albert Marshall ThomasBroad band active element for television arrays
US3056960 *Aug 31, 1959Oct 2, 1962Sylvania Electric ProdBroadband tapered-ladder type antenna
US3086206 *Oct 19, 1960Apr 16, 1963Channel Master CorpEnd fire planar dipole array with line transposition between dipoles and impedance increase towards feed
US3108280 *Sep 30, 1960Oct 22, 1963Univ IllinoisLog periodic backward wave antenna array
US3113316 *May 23, 1960Dec 3, 1963Collins Radio CoUni-directional circularly polarized log periodic antenna
US3134979 *Jan 27, 1961May 26, 1964Granger AssociatesTapered ladder log periodic antenna
US3155976 *Aug 31, 1959Nov 3, 1964Sylvania Electric ProdBroadband straight ladder antenna with twin wire balanced feed supplied via integralunbalanced line
US3163864 *Oct 30, 1962Dec 29, 1964Channel Master CorpEnd fire planar array of v-shaped multi-band dipoles
US3165748 *Mar 19, 1962Jan 12, 1965Marconi Co LtdSeries fed log periodic antenna with coplanar conductor pairs
US3167775 *Sep 29, 1960Jan 26, 1965Rudolf GuertlerMulti-band antenna formed of closely spaced folded dipoles of increasing length
US3182330 *Sep 21, 1960May 4, 1965Gen ElectricVariably spaced arrays of wave radiators and receivers
US3210767 *May 3, 1960Oct 5, 1965Univ IllinoisFrequency independent unidirectional antennas
US3212094 *May 31, 1961Oct 12, 1965Collins Radio CoVertically polarized unidirectional log periodic antenna over ground
US3214760 *Apr 28, 1960Oct 26, 1965Textron IncDirectional antenna with a two dimensional lens formed of flat resonant dipoles
US3221332 *Apr 29, 1960Nov 30, 1965Marconi Co LtdLog periodic antenna with plural crossed dipoles
US3396399 *Mar 24, 1965Aug 6, 1968Winegard CoUltra-high frequency fishbone type television antenna
US3471859 *Sep 30, 1965Oct 7, 1969Simons SylvanIncreased gain broad-band television antenna
US3503074 *Dec 5, 1968Mar 24, 1970Carter Duncan LLog-periodic antenna array having closely spaced linear elements
US4378558 *Aug 1, 1980Mar 29, 1983The Boeing CompanyEndfire antenna arrays excited by proximity coupling to single wire transmission line
US4743916 *Dec 24, 1985May 10, 1988The Boeing CompanyMethod and apparatus for proportional RF radiation from surface wave transmission line
DE1616745B1 *Jun 3, 1960Feb 1, 1973Marconi Co LtdAntennenanordnung mit wenigstens einer gruppe einander paralleler dipolstrahler
Classifications
U.S. Classification343/811, 343/853, 343/792
International ClassificationH01Q11/00, H01Q11/10
Cooperative ClassificationH01Q11/10
European ClassificationH01Q11/10