Патент USA US2113136код для вставки
April 5, 1938. y c. w. HANSÈLI. ET AL ` 2,113,136 ANTENNA y 4 Filed Feb. 3. 1936 F191 F192 TRANS. L/NE HIGH FREQUENCY AFPA KAN/S INVENTOR. NlLS E. LINDENBLAD E' ’ LARENCE W,HANSELL ATTORNEY. Patented Apr. 5, 1938 l 2,113,136 UNITED STATES PATENT OFFICE 2,113,131; ANTENNA Clarence W. Hansell, Port Jeñerson, and Nils E. Lindenblad, Rocky Point, N. Y., assignors to Radio Corporation oi' America, a corporation of Delaware Application FebruaryÍ s,- isss, sei-n1 No. 62,0111l5 Claims. This invention relates to antennas. A primary object is to enable thé transmission of short radio waves with considerable vertical directivity and with uniform and maximum 5 radiation in the horizontal plane. -vA further object is to provide an antenna suit able for use on ultra high frequencies which has a broad frequency response curve whereby it will radiate the modulation sidebands of television, facsimile and other program services. Another object is to provide a mechanically simple antenna structure of pleasing appearance suitable for use on the tops of high buildings and towers. 15 20 ' A further object is to provide a simple me chanical antenna arrangement for use with ultra high frequencies which gives the equivalent of a series of dipoles energized in the same phase with respect to one another. These and other objects of the invention which may appear from a reading of the speciilcation are achieved by providing an antenna in the form of a tube having alternately arranged radiating ‘ sections each a half wave long at the operating 25 frequency and energized such that the currents flowing therein are in the same direction, where by cophasal energization is eiïected. The radia tion from an intermediate section is suppressed by means of a sleeve also a half wave length 30 long surrounding the intermediate section. The sleeve may be either insulatingly positioned with respect to or fastened metallically at its mid point to the antenna tube and is connected to ground by means of a lead a multiple of a halt 35 wave long extending within the tube from ground to the end of the sleeve nearest the high fre quency apparatus. The diameter of the antenna tube is selected to give a desired Width of frequency response 4 curve and is based upon an appreciation of the fact that the width of the curve is increased simultaneously with an increase in diameter of the tube. 4Ol 5O A . ature of the invention is the adjustable sleeve at the extreme end of the antenna tube for obtaining proper adjustment of the length of the antenna. Advantages of the invention are that the an tenna (1) possesses moderately great vertical directivity but no horizontal directivity`when erected vertically; (2) is simple to construct; (3) is rigid in. construction; and (4) is easily adapted for use on the top of a high building. 55 In the accompanying drawing, Figs. 1 and 2 illustrate the invention as applied to two diil‘erent lengths of antennas mounted vertically on the top of a~ building. It will be appreciated, of course, that the antenna may also be positioned horizontally or at any desired angle for obtain (Cl. 250-33) ing directivity in planes other than the vertical l plane. The antenna of Fig. 1 comprises, essentially, a single rod l equal to seven-quarters the length of the communication wave, set one-quarter of a wavelength more or less into the top of a build ing. The portion of the antenna above the roof top consists of two half wavelength radiating portions 2, 2 separated by an eñective non-ra diating portion 3 from which radiation is sup 10 pressed by a surrounding sleeve 4 also equal to a half wave-length. Sleeve 4 is grounded to the roof top by a half wavelength connection I4 which connects with the sleeve at its lower end ` and extends inside the tubular antenna, as 15 shown. Connection I4 may connect to the inside or outside of sleeve 4. The lowest quarter wave length section is prevented from radiating by having it sunk into the roof of the building. The antenna is energized by high -frequency appa 20 ratus, shown conventionally in box form, through transmission line TL which connects with an tenna l at a tapping point which is adjustable to match the impedance of the line TL. In this manner standing waves are set up along the antenna, and the voltage which is eilîective in producing radiation is asìindicated in dotted lines on the sections 2, 2. Sleeve 4 may be insulatingly positioned, or can be fastened metallically at its mid-point to the 30 antenna tube 2. If desired, `sleeve 4 may be grounded at its upper end, in which case con nection I4 should be an even multiple of half the length of the operating wave. An adjustable sleeve 5 aids in adjusting the length of antenna l. In order to broaden the frequency response curve of the antenna so that it may radiate the modulation sidebands, its diameter is made quite large, herein shown as one-fifteenth the wavelength. 40 The system of Fig. 2 is similar to that of Fig. 1 except that the antenna is of greater length. In Fig. 2 there are shown three radiating sections, each one-half wave-length separated from one another by half wavelength non~radiating sec 45 tions in the same manner as shown in Fig. 1. In this case the uppermost lsleeve 4' is grounded to the roof top by a conductor equal to three half wavelengths. Instead of such a grounding ar rangement for sleeve 4', the lower end of the upper sleeve 4' can be connected to the upper end of the lower sleeve 4. It will thus be ap parent that if the antenna is lengthened, each sleeve may be connected to ground over a con nection equal to an odd multiple of a half wave length. Fig. 2 also diiîers from Fig. 1 by show ing another way of coupling the transmission line to the antenna; instead of the direct coupling of Fig. 1, inductive coupling is used, both types of coupling being, of course, interchangeable. 60 2 2,113,136 It will be understood, of course, that the in portion o! the antenna above said roof top being ' vention is not limited to the precise arrange a multiple of a half wave, said roof being ot high conductivity and maintained at `zero radio ment shown in the figures, since various modi fications may be made without departing from the spirit and scope thereof. For example, the frequency potential. 9. An antenna in accordance with claim 6, "il characterized in this that said antenna is mount ed on the top of a building, the lcwermost por tion of said antenna being set below the roof top antennas of Figs. 1 and 2 may be extended sym metrically from a center so as to form a struc ture equivalent to two antennas end to end, for approximately one-quarter wavelength, said somewhat like an extended dipole antenna. Al » portion of the antenna above said roof top being 10 10 so, various arrays of antennas may be used to ob tain additional directivity, It should also be a multiple-of a half wave, said high frequency understood that the expression “sleeve” is not apparatus being coupled to said antenna at the necessarily limited to a continuous, solid ele- - portion below said roof top, said roof top being of ment but also includes a plurality oi?> closely high conductivity and grounded. 10. An antenna comprising two lhalf wave 15 15 spaced, interconnected wires in the form oi' a screen and having the general configuration of length radiating sections separated by another a cylinder. half wavelength section, a sleeve one-half wave length long surrounding said last section and in sulated therefrom for preventing radiation there from, and a connection grounding said sleeve. 20 11. An lantenna for obtaining moderately great What is claimed is: 1. An antenna comprising -two half wave 20 length radiating sections separated by another half wavelength section, and a sleeve one-half wavelength long surrounding said last section for preventing radiation therefrom, the ends of vertical directivity and little or no horizontal directivity, comprising a vertical rod, high fre quency apparatus connected to the lower end of said rod, a sleeve surrounding each alternate half 25 wavelength section of said rod, the portions of ~ said sleeve on both sides of the center being in sulated from the rod, and a connection a multiple of a half wave long connecting each' of said sleeves to ground for preventing radiation from 30 said sleeve on both sides of its center being in 25 sulated from said last section, and a connection grounding said sleeve. 2. An antenna comprising a straight rod hav ing high frequency apparatus connected to one end thereof, alternate half wave sections of 30 which, as measured from the free end, radiate, the surrounding sections. 12. An antennal comprising a substantially straight hollow rod, alternate half wave sections of which radiate, means for preventing radia means for preventing radiation from each half wave section located between radiating sections comprising a sleeve surrounding said section, the ends of said sleeve being insulatingly posi tion from each half wave section located be 35 tioned from said antenna, and a connection for grounding said sleeve. . 35 tween radiating sections comprising a sleeve sur 3. An antenna in accordance with claim 2,4 rounding said section, and a connection inside characterized in this that said antenna is a tube said rod groundìngsaid sleeve. 13. An antenna comprising a substantially and said connection grounding said sleeve runs straight hollow rod, alternate half wave sections 40 40 inside said tube. 4. An antenna in accordance lwith claim .2, of which radiate, means for preventing radia characterized in this that said antenna is a tube tion from each half .wave section located between and said connection grounding said sleeve runs radiating sections comprising a sleeve surround inside said tube, and is an odd multiple of half ing said section, and aconnection inside said rod Y and insulatingly positioned wth respect thereto 45 45 the length of the operating wave. 5. An antenna comprising two half wave`- for grounding said sleeve, said connection ex length radiating sections separated 'by another tending to said sleeve through an aperture in said half wavelength section, and asleeve one-half . rod. e, - . , `14. An- ,antenna> comprising a substantially wavelength long surrounding said last section 50 and supported therefrom only at its mid-point» ~ straight., hollow rod~,‘~¿,alternate lhalf wave sec >'_ Ítionscf which radiate„means for preventing ra for preventing radiation therefrom, and a con 50 nection an odd multiple of a half- wavelengthV diation-from each half 'wave >section located be long grounding said sleeve. ’ I f tween radiating sectionseomprising a sleeve sur , 6. An antenna for obtaining moderately great Árorundingsaid` section, and fa' connection inside 55 vertical directivity and little or no'horizontal-f directivity, comprising a vertical rod, -high >fre saidl rod-grounding- said' `slee've,`.j-.said connection . beingra, multiple o'ft'half «the length of the' operat.` quency apparatus connected to the lower end ing-Wave. u „ „ ~` 55 ,f >15.*_An ' antenna vcomprising a substantially of said rod, an adjustable sleeve, at the >ex- , treme top end of said rod for adjusting the length vvertical hollowrod, alternate vhalf wave sections of which radiate,‘saidyrodubeingmounted on a 60 ` wavelength section _of saidv rod and> insulated _grounded'support 'andbein'g " ¿below the upper distance approxi d ` therefrom, and a_.connection an odd multiple of ’ Isurface of said supportvffor 60 thereof, a sleeve surrounding each alternate half » a halfy wave longïconneoting each of said last - " mately, one-quarterathejflength' of the operating y wave, said'portionhaboveisaid support being a multiple 'of half :the operating wave, ’means for 7. An antenna in> _accordance with claim 16, >preventing radiationi'rom' e‘ach half wave sec characterized in A`this that said rod _is altube whose t tion of saidfrod located ¿ between radiating >sec outer diameter is anvappreciable fraction of- a tions ,c'omprising' a‘shieldsurro'unding said sec half wave long, and' said 'connections'.extend tion, av connection inside said rod grounding said sleeves and ground ¿for preventing radiation from 65 the 'surrounded"fsecfftionvs_. ' ' 70 within said tube from said sleeves togroundi -` wsliieldr' and high frequency apparatus coupled 8.» An antennal ‘in accordance with 'claim` 6,'v .tosaid rod atfthe -portion below the upper sur characterized in this. that-said antenna'is mount- . face of> said' support.: e ed on the topfoii> a- building,_the lcwermost por- _ Y tion of said antenna beingy set -below the roof top 75 for approximately o'rie-ciui'trtery wavelength, said ì CLARENCE _W._ HANSELL.