US2147807A - Transmission line - Google Patents

Transmission line Download PDF

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US2147807A
US2147807A US109658A US10965836A US2147807A US 2147807 A US2147807 A US 2147807A US 109658 A US109658 A US 109658A US 10965836 A US10965836 A US 10965836A US 2147807 A US2147807 A US 2147807A
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Prior art keywords
line
waves
sections
impedances
frequency
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US109658A
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Alford Andrew
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Mackay Radio & Telegraph Co
MACKAY RADIO AND TELEGRAPH Co
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Mackay Radio & Telegraph Co
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Priority to NL84932D priority Critical patent/NL84932B/xx
Application filed by Mackay Radio & Telegraph Co filed Critical Mackay Radio & Telegraph Co
Priority to US109658A priority patent/US2147807A/en
Priority to DEI3278D priority patent/DE894576C/de
Priority to FR829274D priority patent/FR829274A/fr
Priority to GB30638/37A priority patent/GB493235A/en
Priority to NL84932A priority patent/NL51387C/xx
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P1/00—Auxiliary devices
    • H01P1/20—Frequency-selective devices, e.g. filters
    • H01P1/213—Frequency-selective devices, e.g. filters combining or separating two or more different frequencies
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B11/00—Communication cables or conductors
    • H01B11/18—Coaxial cables; Analogous cables having more than one inner conductor within a common outer conductor
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q5/00—Arrangements for simultaneous operation of antennas on two or more different wavebands, e.g. dual-band or multi-band arrangements

Definitions

  • This invention relates to a transmission adjuster device used with transmission lines to serve somewhat the same purposes ordinarily served by transformers, lters and the like.
  • the object of the present invention is to provide a structure which may be readily applied to a transmission line for altering the transmission of waves thereon in certain respects without producing any alteration in other respects. More specifically it is an object to provide a circuit arrangement of impedances applied to a transmission line in such a way that no change arrangement to be applied to a transmission line which is subjected to two different frequencies so as to sharply alter the transmission characteristics for the Waves of one frequency f without altering in any important particular the transmission of waves of the other frequency F.
  • the method and means for accomplishing these objects may be useful in many different fields and it is the purpose of the present invention to provide arrangements foraccomplishing these objects in all the diierent types of systems in which such a selective inuence on transmission may be desirable.
  • the structure of the present invention presents the great advantages that the transmission line itself is employed as part of the network so that the additional portions which must be af- 'ilxed thereto may be of much smaller dimensions than with other types of phase shifting or building-ou arrangements.
  • the present arrangement is adapted to be applied to a trans- (Cl. P18-44) mission line without cutting the transmission line and is arranged so that it may be readily adjusted along the transmission line.
  • the present structure also presents marked advantages from the standpoint of resonant potentials. As will be understood from the description and analysis of the system given below, the present arrangement can readily be designed to avoid the occurrence of unduly high standing wave potentials which might result in corona losses or even flash-over.
  • two impedances are connected to a transmission line each of the impedances being applied in shunt across the line.
  • the impedance values and the spacing between these two impedances are so adjusted that for one -particular frequency the transmission of waves along the line will take place just as if the impedances were not connected thereto, except that the phase of said waves will sometimes generally be altered.
  • the distribution will, it is true, be considerably altered but with respect to those portions of the line outside the impedances substantially no reflections or attenuations will be produced, but only in some cases a change of phase.
  • Two impedances connected and proportioned in this manner ar ⁇ hereinafter referred to as conjugate with respect to the frequency for which the attenuations and reflections are unaffected.
  • this above described structure or-combination of two impedances with a transmission line is made use of for adjusting the relative phases of the waves in two antennae fed from the same source and employed as an array for directive transmission.
  • this same structure is employed in a transmission line used for feeding a single antenna at two different frequencies, the function of the conjugate impedances in this case being to match the impedance of the antenna to the characteristic impedance of the line at one frequency in such a way that the matching ormismatching which would exist at the other frequency in the absence of these impedances remains u'ndisturbed. This will be true whether the two frequencies are applied separately or together.
  • this same type of structure is employed for blocking or completely preventing the passage of an undesired frequency f along a certain portion of transmission line while permitting the transmission vof another desired frequency F this same portion of line.
  • the transmission of the 'desired frequency F is not only notblocked but is completely unaffected bythe presence of the impedances which serve to block the frequency l.
  • this same type of 'structure is employed for grounding a transmission line as a protection against lightning. stray potentials, or
  • Fig. 1 represents a transmitting system comprising a transmission line subjected to two different frequencies, F and f, and shows the nature of the disturbances whichmay exist along such a line before the impedance matching means of the present invention are applied.
  • Fig. 2 illustrates the-same transmitting system after the application of thepresent invention and shows how the standing wave disturb- 1 ances which existed in Fig. 1 are modified by means of the present invention.
  • Figs. 3, 4, and 5 illustrate alternative forms of 'the present invention which are slightly different in construction from that shown in Fig. 2 but are substantially equivalent in effect.
  • Fig. 1 represents a transmitting system comprising a transmission line subjected to two different frequencies, F and f, and shows the nature of the disturbances whichmay exist along such a line before the impedance matching means of the present invention are applied.
  • Fig. 2 illustrates the-same transmitting system after the application of thepresent invention and shows how the standing wave disturb- 1 ances which existed in Fig. 1 are
  • FIG. 6 represents a set-up for empirical measurements which may be employed for determining the proportions and dimensions of the structures shown in Figs. 2, 3, 4 and 5.
  • This ligure (Fig. 6) also includes a representation of the standing waves which occur in .diiIerent portions of the transmission line and is dimensioned so as to aid in understanding the formulae for proportioning the different parts.
  • Fig. 7 represents a transmitting system ln which two an ⁇ - tennae are fed from a single source. In this hgure, a pair of conjugate impedances according to the present invention are employed for ad' justing the phase of one of these antennae relative to the'phase of the other antenna.
  • Fig. 6 represents a set-up for empirical measurements which may be employed for determining the proportions and dimensions of the structures shown in Figs. 2, 3, 4 and 5.
  • This ligure (Fig. 6) also includes a representation of the standing waves which occur in .diiIerent portions of the transmission line
  • FIG. 8 illustrates a portion of a transmitting system in which two separate frequencies are fed from two separate sources over two separate feeder lines to one transmission line.
  • two pairs of conjugate impedances in accordance with the present invention are employed, each of which serves to block one of the transmission feeder lines with respect to the frequency transmitted over the other feeder line.
  • Fig. 9 represents a pair of conjugate impedances in accordance with the present invention applied to a transmission line and connected so as to serve for draining this line to ground.
  • Fig. l0 illustrates the use of a plurality of pairs of impedances in accordance with the present invention applied to a line which is subjected to three different frequencies.
  • 'Ihese pairs of impedances are arranged to cause no important change in transmission characteristics with respect to two of the frequencies while causing a desired change with respect to the third frequency.
  • Figs. 11, 12 and 13 illustrate the application to a transmission line of other possible forms of impedances which are not preferred but may be used for any of the purposes of the present invention.
  • represents a transmitter station from which waves for frequency F as well as waves of frequency f are transmitted over transmission line
  • I I0 which may be a transformer or a conventional building-out section
  • 02 has been matched to the characteristic-impedance of the antenna
  • frequency f it is assumed that the antenna and line are not matched.
  • a disturbance upon the feeding of waves of this frequency from the transmitter station, a disturbance will be set up as shown in the lower curveof Fig. 1 just above the transmission line.
  • Sucha standing wave condition is undesirable both from' the standpoint of losses along the transmission' line and from the standpoint of maximum efficiency in delivering the energy from the transmitter station to the line.
  • a pair of impedances are to be connected to the transmission line at the locations indicated in Fig. 1 by dot and dash lines. 'Ihe positions at which these impedances -must be connected are related to the position qt the standing wave pattern which is to be eliminated. Dimension -s" in Fig. 1 represents.
  • 0, and the radiating antenna 203 correspond exactly tothe parts
  • are shown connected to the transmission line at the locations indicated by the dot-dash lines.
  • each of the impedances consists of a section of transmission line (having the same characteristics as transmission line 202) connected at one end to the transmission line and short-circuited at the other end.
  • are determined in accordance with an experimental procedure or a set of mathematical formulae as fully explained below.
  • are conjugate. In all those portions of the transmission line which lie outside of these sections no change in the transmission characteristics of the line is produced for waves of frequency F-excepting a change of phase which is often of no importance. As illustrated by the upper curve of Fig. 2, standing waves are produced at frequency F in that part ofthe transmission line 202 which lies between the sections 22
  • not only create a new form of standing waves in that portion of the transmission line which lies between them but also cause a desired modification of the standing wave pattern between the rear section 220 and the transmitter station 20
  • the standing wave pattern for frequency l (due to the mismatch at frequency f of antenna. 203 together with matching device 2
  • the previously existing standing waves are completely neutralized or eliminated, so that with respect to transmitter station and the rear portions of transmission line 202 the transmission line is perfectly matched to the antenna. It is assumed that the major part of the transmission line' 202 lies behind the rear section 220 so that most of this transmission line is free from standing waves.
  • Fig. 3 illustrates a pair of sections of a dierent form which may be used for the same purposes as 220 and 22
  • consist of sections of transmission line (having the same characteristics as the main transmission line 302) connected at one end to this main transmission line and open-circuited or insulated at their free ends.
  • will be somewhat longer than the lengths of the corresponding sections 220 and 22
  • FIG. 4 represents a pair of sections of which the rear one 420 is of the closed type while the front one 42
  • a simple empirical measuring procedure may be employed.
  • a trial source 606 is connected to a test transmission line 602 which is terminated at its far end in a reilectionless terminating resistor 608.
  • the trial source 606 is arranged so that either frequency F or frequency f may be generated.
  • the resistor 608 should be adjustable so that it may simulate the surge impedance of the transmission line 602 for either of these frequenciesunless the surge irnpedances at the two frequencies are so closely the same that a single fixed resistor may be used. Any convenient form of current meter may be employed to indicate the absence of standing waves so as to be sure that the resistor is actingas a proper termination.
  • the transmission lineA 602 should be exactly equivalent to the transmission line with which the conjugate sections are actually to be used.
  • are now slidably connected tothe trial transmission line 60
  • This pair of sections may be of any form, such as the forms illustrated in Figs. 2, 3, 4 and 5.
  • shouldalso be readily adjustable. In the case of a closed section, this adjustability may be attained .simply by providing a slidable shortcircuiting wire for short-circuiting the section at an adjustable point.
  • telescopic wire may be used. For this type, however, the adjustment may be most easily performed by employing a section which is known to be too long, and then gradually shortening it by cutting until the desired adjustment is reached. In the case of such open sec.- tions, moreover, minor adjustments of length may be made by bending over the ends of the wire.
  • the trial source is now arranged to generate frequency F and the lengths of the sections as well as the distance between them are adjusted until conjugacy is reached, i. e. until there are no standing waves along the transmission line except between the sections 620 and 62
  • conjugacy is reached, i. e. until there are no standing waves along the transmission line except between the sections 620 and 62
  • only two types of conjugacy will be found, each of which, however, includes an infinite number of adjustments of rear section length with corresponding adjustments of the front section length and the spacing distance between sections.
  • the rst such type of conjugacy, symmetrical conjugacy requires a spacing between sections which is in general not equal to an integral number of half wave-lengths and must be determined by measurement (or from a formula as explained hereinafter).
  • should always be identical.
  • the lengths of the front and rear sections will differ by one-quarter wave-length or by an odd number of quarter wave-lengths. 'Ihis rule will greatly simplify the number of adjustments which need to be made in attaining conjugacy of the symmetrical type.
  • the second type of conjugacy requires that the spacing distance between sections should always be an integral number of half wave-lengths.
  • the lengths of the two sections will in general be different.
  • the sum of the lengths of the front and rear sections will always be an integral number of half wave-lengths.
  • the sum of the front section length plus the rear section length will always be an odd number of quarter wave-lengths.
  • the trial source B06 and the resistor 608 should be altered so that frequency f is transmitted over the line 602 and absorbed without reflection at the termination 608.
  • a standing wave pattern will be set up between the trial source 606 and the front section 62
  • should be noted as well as the intensity factor 1'.
  • the value of 1' may conveniently be chosen as a tabulating index against which the other quantities, such as the location dimensions, the rear section length a or p, the front section length b or q, andthe spacing distance d may be listed.
  • a complete tabulation of this type covering a sufficient number of values of 1' and the corresponding other quantities to determine quite accurately all practicable proportions for a given pair of frequencies may be readily carried out in a short time.
  • a or a length of rear section in degrees for g sections of short-circllited type).
  • B or b length of front section in degrees (for sections of short-circuited type).
  • D or d distance between sections in degrees (any types of sections). :frequency for which sections are conjugate.
  • H pnase delay (in degrees) caused by conjugate pair of sections (a negative value of H indicates a phase advance).
  • r ratio of current minima to current' maxima for those standing waves (of frequency f) which are to be kept out of the rear portions of the transmission line by the pairof sections.
  • s distance forward from front section to next current peak of those standing waves which are to be kept out of the rear portions of the transmission line by the pair of sections.
  • N any positive or negative integer. N as used in one formula is not necessarily equal to N as used in another formula.
  • the known factors will usually be the frequencies f and F and the intensity factor 1. In such a case, it is most convenient to solve the problem graphically.
  • a length of the rear section (A or P) may be arbitrarily assumed.
  • the length of the front section (B or Q) and the spacing distance between the sections (D) may be readily found from the simple conjugacy relations. Any number of such quantities may theoretically be found which will satify the conjugacy conditions, but only a small number of these lengths and spacing distances are of practical size.
  • the corresponding values a or p, b or q, d may be found.
  • Ihese latter quantities represent the same distances as the former quantities but are expressed in terms of the wave-length of the non-conjugate wave instead of the Wave-length of the conjugate wave. From these latter values, the quantities r and s may be readily computed and all these quantities are then plotted or tabulated against 1. If the computations are intended for use -with only one specific problem, it will be suiiicient to compute widely separated points until the approximate desired value of r is approached and then to compute the points closer together in well known manner. Finally, the set of quantitles corresponding to the desired r are selected either from the graphical curves or the tabulations.
  • a pair of sections having these tabulated dimensicns are then constructed and connected to the tranmission line with a spacing distance d as also shown by the tabulations.
  • the location of this Whole pair of impedances relative to the standing wave which is to be neutralized or blocked is determined by the tabulated value s as illustrated in Figs. 1 and 2.
  • a final trimming adjustment may be made by slightly varying merely the length of one of the sections or, if greater accuracy is desired, by alternately varying the lengths of the sections and the spacing distance d.
  • Fig. 7 illustrates the use of a pair of conjugate sections for shifting the phase of a wave of frequency F without altering any other characteristics of its transmission.
  • is a transmitting station over which waves of frequency F are transmitted over lines 102, 101 and 151 to the radiating antennae 103 and 4153.
  • 0 and 160 the impedances of the antennae are matched to the surge impedance of the transmission line and that the surge impedance of the main portion of single transmission line 102 is matched by means of device 1
  • 'I'his object may be achieved by the use of a pair of conjugate impedances 120 and 12
  • This pair of impedances is shown as applied to the longer branch line 151 but might equally Well be applied to the shorter branch line 101.
  • This pair of impedances also has been shown as consisting of two closed sections of the type illustrated in Figure 2, but any of the types shown in Figs. 3, 4 and 5 might equally well be used. The lengths of the sections 120 and 12
  • the proportions of the conjugate pair are now varied (as for example by altering the length of the rear section 120 and then correspondingly altering the length of the front section 12
  • FIG 8 shows the'application ⁇ of conjugate pairs to branch feeder lines for the purpose of blocking these feeder lines with respect to certain undesired frequencies.
  • is adapted to supply waves of frequency f (whose wave-length is w) over feeder ble to permit waves of frequency F to back up over feeder transmission line 800 into transmitter station 80
  • the surge impedance of feeder transmission line 809 is exactly matched to the surge impedance of the main transmission line 802 and similarly with regard to feeder transmission line 859 and main transmission line 802.
  • Fig. 8 A pair of impedances 810 and 81
  • will be-so far as frequency f is concerned-exactly the same as a short-circuit located at the position of impedance 81
  • the location of the pair of impedances along the feeder line 859 should now be adjusted so xthat the distance k between section 81
  • the distance 1c is understood to be measured with respect to the wave-length w of the waves of frequency f.
  • feeder line 859 is not only blocked with respect to waves of frequency f but is virtually' caused to be non-existent for these waves. since this feeder line with its pair of sections 810 and 81
  • On feeder line 809 a pair of conjugateimpedances 820 and 82
  • the main transmission line 802 may now transmit the waves of both frequencies to, any suitable type of antenna; or if desired these waves may be separated from each other and diverted respectively into two separate feeder lines by an arrangement exactly Asimilar to that just described for'brlnging these waves together.
  • Fig. 9 illustrates a pair of conjugate 'sections 828 and 92
  • a special pair of sections may, if desired, be provided on a transmission line merely for the purpose of grounding it. Any of the types of pairs shown in Figs. 2, 4. or may be used. The type shown in Figs. 4 and 5 will only provide one grounding point along the line.
  • Fig. 10 illustrates the use of two pairs of conjugate sections
  • This construction may be derived as folllows:
  • the first pair comprising sections
  • is also constantly kept conjugate at this same frequency.
  • any 'one vdimension of either one of these pairs is arbitrarily fixed (thus determining all the dimensions of that pair) while one dimension of the other pair is progressively altered (with corresponding alterations of the remaining dimensions of this other pair) until the total effect of both pairs with respect to frequency f is zero; i. e. until the pair of pairs is conjugate at frequency f.
  • the resulting intensity factor r' of the standing current waves produced by the pair of pairs at the third frequency f' is now noted and tabulated with all the corresponding data.
  • Figs. l1, 12 and 13 illustrate the use of other forms of impedancev which may be desirable in certain cases.
  • the preferred form oi' impedance is comprised of sections of transmission line, these sections being either open-circuited or shortcircuited at the free end. These sections of transmission line have been assumed to be of the same characteristics as the transmission line to which the sections are attached. Although such a construction lias many advantages and is particularly simple from the standpoint of computation and design, it may be desirable in some cases to use impedances of other forms.
  • Fig. 11 illustrates, for example, the use of two impedances H and
  • Fig. 12 shows the use of two capacitances
  • Fig. 13 illustrates the use of two special impedances
  • any of the impedances shown in Figs. 11, 12 or 13 may be combined with anyother type of impedance to form a conjugate pair since it is not' essential that both impedances of a pair be of the same construction.
  • the impedances used will preferably be practically pure reactances so that the resistive component may be neglected.
  • the impedances to be used would be of this type.
  • the formulae given above can still be employed by merely considering that C and G are complex numbers such that fC and :iG represent the impedances of the rear and front elements respectively. For most purposes, however, such involved calculations are wholly unnecessary.
  • the transmitter stations should be understood to be wave sources of any type (such as collecting antennae, wave carrying lines bearing incoming energy, wave generators etc.).
  • the radiating antennae should be understood to be wave receiving devices of any type (such as detectors, receiving stations, wave carrying lines bearing outgoing energy, eta).
  • the radiating antennae may be used as collecting antennae the transmitter stations being merely replaced byl "receiving stations and the transmission arrangements in l between being unchanged.
  • the wave sources may be replaced by wave receiving devices of the same impedance and the wave receiving devices by wave sources of the same impedance.
  • Fig. 7 and its appertaining description if conversely interpreted discloses a structure for adjusting the relative phases of two wave sources connected to one transmission line.
  • Fig. 8 and its description can be taken as explaining a structure for separating two waves which arrive over one transmission line and areto be diverted onto two separate branch lines.
  • a transmission system comprising a translating device; a translating apparatus, a line connected between said device and said apparatus the surge impedance of said line differing from the impedance of the device, said line serving to carry waves of at least two predetermined frequencies between said device and said apparatus, a pair of sections of transmission line having the same characteristics as said line, one end of each of said sections being connected to said line, the length of each of said sections and the distance between their points of connection to said line being so related that for waves of one of said frequencies the standing wave pattern along'.
  • the line outside of said points of connection is the same as if said sections were not connected, whereas for waves of the other of said frequencies all standing waves between said apparatus and the section nearest thereto are substantially suppressed.
  • a transmission system comprising a translating device, a translating apparatus, a line connected between said device and said apparatus the surge impedance of said line differing from the impedance of the device, said line serving to carry waves of at least two predetermined frequencies between said device and said apparatus, a pair of sections of transmission line having the same character as said line one end of each of said sections being connected to said line, the length of each of said sections and the distance between their points of connection to said line being so related that for waves of one of said frequencies the combined impedance of said device, said pair of sections and those portions of the line interconnecting said device and sections is for one of said frequencies equal to the surge im-- pedance of said line, whereas for the other of said frequencies the corresponding combined impedance is the same as if said sections were not connected.
  • a transmission system comprising a source of waves of at least two predetermined frequencies, an apparatus to which said waves are to be transmitted, a transmission line interconnecting said source and said apparatus, the surge impedance of said line diering from the input impedance of said apparatus, a pair of impedance elements connected to said line at two separate points between said source and said apparatus, the impedances of said elements and the distance between said points being so related that waves of one of said frequencies are transmitted from said source to said apparatus in essentially the same manner as i1' said impedances were not connected, whereas the transmission of waves ofthe other of said frequencies is altered by the presence of said impedances whereby waves of said other frequency are transmitted from that section of the line between the source and the nearest impedance element into that amano? section of the line to which the impedance elements and the apparatus are connected without reflection.
  • a transmission system comprising a source of waves of at least two predetermined frequencies, an apparatus to which said waves are to be transmitted, a transmission line interconnecting said source and said apparatus, the surge impedance of said line being diierent from the impedance of said apparatus, a plurality of impedances connected to said line at separate points between said source and said apparatus, the values of said impedances and the spacing between thembeingisuch that the waves of one of said frequencies are transmitted along said line with the same attenuations and reflections at all points outside of said impedances as if said impedances were not present, whereas the transmission of waves of another of said frequencies is altered by reections at said impedances so that the resulting total reflection of the waves of said other frequency toward said source is zero.
  • a transmission system comprising a source of waves of at least two predetermined frequencies, an apparatus for receiving said waves, a transmission line interconnecting said source and said apparatus, the surge impedance of said line being different from the impedance of said source, a plurality of impedances connected at separate points along said line between said source and said apparatus, the values of said impedances and the spacing between them being so related that the total apparent impedance of said source, together with said impedances and those portions of the line interconnecting said source and said impedances is equivalent for one of said frequencies to the surge impedance of said line, whereas for the other of said frequencies the corresponding total apparent impedance Vis equivalent simply to the impedance of the source as viewed through that portion of the transmission line which interconnects the source and the impedances.
  • a transmission system comprising a transmission line adapted to carry waves of a predetermined frequency, a plurality of impedance elements connected across said line at separate positions. the impedances of said elements andv their spacing along said line being so inter-related that thecombined reflections caused by said elements at every point along the line outside of all of them is zero for waves of said frequency, and a connection from a point of one of said elements to ground.
  • a transmission system comprising a transmission line adapted to carry waves of a predetermined frequency, a plurality of impedance elcments connected across said line at separate positions, the impedances of said elements and their spacing along said line being so interrelated that the combined reilections caused by said elements at every point along the line outside of all of them is vzero for waves of said frequency, and a connection from the mid-point of one of said elements to ground.
  • a transmission adjusting arrangement for transmission lines and the like over which at least three frequencies are transmitted comprising at least three impedance elements connected to the line at points separate from one another, the impedances of each of said elements and the separation between their points of connection to the line being so related that waves of at least two of said frequencies are transmitted with the ⁇ same reections and attenuations at every point along the line outside of said elements as if said elements were not connected to said line, whereas the total reflection undergone by waves of another of saidfrequencies is altered by the presence of said elements.
  • a transmission system comprising a transmission line adapted to carry waves of at least two predetermined frequencies, two branch lines connected to said rst named line and each adapted to carry waves of one of said frequencies,
  • the spacing between the ⁇ junction of the branch lines and the impedance element nearest thereto on one of the branch l lines being an integral number of quarter Wave lengths with respect to the frequency adapted to be carried by the other branch line and the relation between the spacing and impedance values of the elements on said first named branch line being such that these elements produce no essential alteration in the waves transmitted along said first named branch line, while simultaneously being such that these elements act like a short circuit for waves of the frequency carried by said other branch line.
  • a transmission adjusting arrangement for transmission lines and the like carrying a plurality of frequencies comprising a set of impedance elements connected to the line at spaced points, the spacing between said elements. being proportioned vwith respect to the impedances of said elements so that with respect to waves of at least one of said frequencies the backwardly ltraveling waves produced by partial reiiection of said waves at the i'lrst of said impedances encountered by said waves are equal in' amplitude and opposite in phase to the backwardly traveling waves produced by reflection at the second 40 of said impedances of that part of said waves passing through said rst impedance, whereby at said one of said frequencies the standing-wave pattern on the line outside said elements is the same as if said elements were not connected.
  • A,transmission adjusting arrangement for transmission lines and the like carrying a -plu- 5 rality of frequencies comprising a set of im- -pedance elements connected to the line at spaced points, the spacing between vsaid elements being proportioned with respect to the impedances of each of said elements so that with respect to 10 waves of atleast one of said frequencies the backwardly traveling waves produced by partial reflection of said waves at the first ofl said impedances encountered by said waves are equal in amplitude and opposite in phase to the back- 15 wardly traveling waves yproduced by reflection at the second of said impedances of that part of said waves passing through said first impedance whereby at said one of saidplfrequencies the total refiection produced by said set of ele- 20 ments is zero.
  • a transmission adjusting arrangement for transmission lines/and the like over which at least one predetermined frequency is transmitted comprising a set of impedance elements cong5 nected to the line at spaced points, the spacing between said elements being proportioned with respect to the impedance of each 'of said elements so that with respect to waves of said frequency, the backwardly traveling waves produced by par- ⁇ 30 tial reection of said waves at the first of said impedances encountered by said waves are equal in amplitude and opposite in phase to the backwardly traveling waves produced by reflection at the second of said impedances of that part u of said waves passing through said flrst impedance, whereby at said one of said frequencies the standing-wave pattern on the line outside said elements is the same as if said elements were not connected.
US109658A 1936-11-07 1936-11-07 Transmission line Expired - Lifetime US2147807A (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
NL84932D NL84932B (xx) 1936-11-07
US109658A US2147807A (en) 1936-11-07 1936-11-07 Transmission line
DEI3278D DE894576C (de) 1936-11-07 1937-11-06 Anordnung zur UEbertragung von zwei oder mehr Wellenzuegen ueber Leitungen
FR829274D FR829274A (fr) 1936-11-07 1937-11-06 Lignes de transmission d'ondes électriques
GB30638/37A GB493235A (en) 1936-11-07 1937-11-08 Improvements in or relating to electrical high frequency transmission lines
NL84932A NL51387C (xx) 1936-11-07 1937-11-08

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US109658A US2147807A (en) 1936-11-07 1936-11-07 Transmission line

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US2147807A true US2147807A (en) 1939-02-21

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Application Number Title Priority Date Filing Date
US109658A Expired - Lifetime US2147807A (en) 1936-11-07 1936-11-07 Transmission line

Country Status (5)

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US (1) US2147807A (xx)
DE (1) DE894576C (xx)
FR (1) FR829274A (xx)
GB (1) GB493235A (xx)
NL (2) NL51387C (xx)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2439235A (en) * 1945-02-14 1948-04-06 Rca Corp Reactance compensation system
US2457123A (en) * 1943-08-26 1948-12-28 Standard Telephones Cables Ltd Coupling arrangement
US2467292A (en) * 1944-02-29 1949-04-12 Bell Telephone Labor Inc Support for conductors of signal transmission lines
US2537341A (en) * 1944-05-22 1951-01-09 Bell Telephone Labor Inc Tuning arrangement
US2593474A (en) * 1944-10-03 1952-04-22 Us Sec War Antenna matching section
DE972852C (de) * 1943-02-07 1959-10-08 Pintsch Bamag Ag Ultrahochfrequenzbandfilter fuer UEbertragungsleitungen elektromagnetischer Schwingungen
US2956247A (en) * 1956-01-26 1960-10-11 Sperry Rand Corp Broad band microwave phase shifter
US3384841A (en) * 1966-03-10 1968-05-21 Bell Telephone Labor Inc Ferrite phase shifter having longitudinal and circular magnetic fields applied to the ferrite
EP0435752A1 (fr) * 1989-12-29 1991-07-03 Thomson-Csf Diplexeur à large bande, en particulier pour ondes décamétriques
CN114137276A (zh) * 2021-11-05 2022-03-04 中国电力工程顾问集团西南电力设计院有限公司 一种不等间距分段高压电缆感应电压的计算方法

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE949409C (de) * 1939-11-26 1956-09-20 Dr Otmar Stuetzer Veraenderbarer Transformator fuer Hohlleiter
DE3027714A1 (de) * 1980-07-19 1982-02-11 Licentia Patent-Verwaltungs-Gmbh, 6000 Frankfurt Transformationsanordnung zur anpassung eines verbrauchers an eine speiseleitung bei hohen frequenzen

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE972852C (de) * 1943-02-07 1959-10-08 Pintsch Bamag Ag Ultrahochfrequenzbandfilter fuer UEbertragungsleitungen elektromagnetischer Schwingungen
US2457123A (en) * 1943-08-26 1948-12-28 Standard Telephones Cables Ltd Coupling arrangement
US2467292A (en) * 1944-02-29 1949-04-12 Bell Telephone Labor Inc Support for conductors of signal transmission lines
US2537341A (en) * 1944-05-22 1951-01-09 Bell Telephone Labor Inc Tuning arrangement
US2593474A (en) * 1944-10-03 1952-04-22 Us Sec War Antenna matching section
US2439235A (en) * 1945-02-14 1948-04-06 Rca Corp Reactance compensation system
US2956247A (en) * 1956-01-26 1960-10-11 Sperry Rand Corp Broad band microwave phase shifter
US3384841A (en) * 1966-03-10 1968-05-21 Bell Telephone Labor Inc Ferrite phase shifter having longitudinal and circular magnetic fields applied to the ferrite
EP0435752A1 (fr) * 1989-12-29 1991-07-03 Thomson-Csf Diplexeur à large bande, en particulier pour ondes décamétriques
FR2656741A1 (fr) * 1989-12-29 1991-07-05 Thomson Csf Diplexeur a large bande, en particulier pour ondes decametriques.
CN114137276A (zh) * 2021-11-05 2022-03-04 中国电力工程顾问集团西南电力设计院有限公司 一种不等间距分段高压电缆感应电压的计算方法
CN114137276B (zh) * 2021-11-05 2023-08-18 中国电力工程顾问集团西南电力设计院有限公司 一种不等间距分段高压电缆感应电压的计算方法

Also Published As

Publication number Publication date
NL84932B (xx) 1900-01-01
DE894576C (de) 1953-10-26
FR829274A (fr) 1938-06-17
GB493235A (en) 1938-10-05
NL51387C (xx) 1941-11-15

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