US1487339A - Radio signaling system - Google Patents

Radio signaling system Download PDF

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Publication number
US1487339A
US1487339A US438544A US43854421A US1487339A US 1487339 A US1487339 A US 1487339A US 438544 A US438544 A US 438544A US 43854421 A US43854421 A US 43854421A US 1487339 A US1487339 A US 1487339A
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Prior art keywords
antenna
currents
receiving
conductors
series
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Expired - Lifetime
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US438544A
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English (en)
Inventor
Edward W Kellogg
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General Electric Co
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General Electric Co
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Priority to US438544A priority Critical patent/US1487339A/en
Priority to FR25944D priority patent/FR25944E/fr
Priority to NL14381D priority patent/NL14381C/xx
Application granted granted Critical
Publication of US1487339A publication Critical patent/US1487339A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q11/00—Electrically-long antennas having dimensions more than twice the shortest operating wavelength and consisting of conductive active radiating elements
    • H01Q11/02—Non-resonant antennas, e.g. travelling-wave antenna

Definitions

  • My present invention relates to radio receiving systems and more particularly to an improved arrangement of an antenna for receiving purposes.
  • One of the objects of my invention is to provide a receiving antenna which will be an efiicient means for receiving radio signals from a desired direction to the substantial exclusion of signals coming from' other directions.
  • a receiving antenna having marked unidirectional properties.
  • a long horizontal antenna is employed which extends preferably in the general direction of transmission of the signals to be received and which is preferably of a length of at least the order of magnitude of a half wave length of the signals to be received".
  • signals coming from a desired station will be found to be strongest at the end of the antenna which is farthest from the transmitting station While signals coming from the opposite direction will be very weak at that end.
  • a second object of my invention is to provide means whereby the receiving station may be located at any desired convenient point along the length of the antenna, and the necessity of locating the receiving station at the point. where the relation of the desired signaling currents received to other currents is most favorable will be eliminated.
  • a balanced two wire transmission line may be used. If it isdesired to transmit the currents from one point on the line of the antenna to another point also on the line of the antenna, the balanced transmission line would normally belocated 'closeto or under the antenna. This might be objectionable since the extra wires would be likely to have-a disturbing effect on the action of the antenna. Any disadvantage of such an arrange'mentmay be avoided as Ihave found that by using two wires in multiple as the antenna, the same pair of wires can be made to act as a transmission line.
  • vention therefore I provide suitable arrangewhich is arran ed in such a way that the re'-' undesired .currents produced 'by ing from directions more than 90 DCver will not aflected by currents set up in the antenna "by waves coming from the opposite direction to that of the signals to be received no matter how strong such currents may be at the receiving station.
  • Still another ob'eet of my invention is to provide means or eliminating the effect upon the receiving station of these small waves comfrom the direction of the transmitting station.
  • the surge impedance of the antenna may not be the best imf edance to employ in the ground connec- -tion of the antenna nearest the transmitting station and therefore in. order to attain this object of my invention I rovide an impedance which is preferably adiustable in order that the best operating conditions may readily be obtained.
  • This impedance i order to more nearly eliminate the objectionable efi'ects, may differ from the surge impedance of the antenna either in its resistance or reactive component or in both.
  • I provide a long horizontal antenna which is preferably made up of at least two parallel wires 1 and 2, the opposite endsof' which are grounded at 3 and 4.
  • This antenna is preferably so constructed or its constants so adjusted that the current wave therein will travel along its length at the same velocityv as that of the signaling wave in space so that the current wave will gradually grow in amplitude as it travels along the conductor. If it is desired to receive a signal which approaches the antenna from the end- 3, the amplitude of the currentiset up in the antenna at 3" by the desired wave will be extremely small, while at the end 4 the amplitude of the current will be a maximum. It may however be more convenient to locate the receiving station at end 3.
  • transformer system which may be made up of two similar transformers 5 and 6 as indicated, or the windings of these two transformers may be combined in one transformer if desired.
  • the primary windings 7, 7 of these two transformers are connected in series with the ground connection at 4 and each of the ground through the primary windings 7, 7 and are transferred back upon conductors 1 and 2 so as to flow in opposite directions through these two conductors.
  • the conductors 1 and 2 thu form the two sides of a transmission circuit which is closed at the receiving station through the primary windings 10, 10 of a similar pair of transformers 11, 12.
  • the secondary windings 13, 13 of these transformers are connected in series with the receiving apparatus.
  • the signaling currents transmitted from end 4. of the an tenna flow throu h the primary windings 10, 10 in series.
  • urrents received upon the antenna, howeyer, from waves traveling from end 4 toward-end 3 flow through the primary windings 10, 10 in parallel to ground and hence produce equal and opposite effects in the secondary windings 13, 13.
  • the receiving apparatus will be unaifect ed by such currents.
  • an impedance consisting of a variable resistance 14, variable inductance 15, and variable capacity 16.
  • this impedance should be made approximately equal to the surge impedance of the antenna.
  • phase of the component reflectedin this way may not be correct for producing the desired neutralization.
  • a capacity reactance or an inductive reactance of small amount may be introduced by off-tuning the series tuned circuit made up of inductance 15 and capacity 16, the reactance introduced in this way being suflicient to produce the desired phase in the reflected component.
  • Fig. 2 I have indicated an arrangement which may be employed in case it is desired to locate the receiving station at some intermediate point along the length of the antenna.
  • two transformers 17 and 18 are provided having their primary windings inserted in conductors 1 and 2, respectively, and having their secondary windings connected to the receiving apparatus in such 'a way that currents flowing in opposite directions through the two conduct'orswill add in the receiving apparatus while currentsflowing in the same direction will oppose each other.
  • a single't ransformer of suitable design. may be made to perform the function of the two transformers shown. In order that the introduction of a transformer or pair of transformers,- in a location antenna.
  • tionable reflections it. is generally dcsi "able 'that it introduce as little impedance as possible into the antenna.
  • Fig. 2 a pair of condensers 19 by which the inductive re'actance of the trans: former windings may be neutralized. If a single transformer is used with close coupling between the two primary windings the reactance to currents flowing in the same direction in the two wires will be low, and this fulfills the condition for avoiding reflections in the antenna.
  • Fig. 3 Ihave indicated an arrangement in which the antei ria is utilized as a transmission line as in Figs. 1 and 2, but in which the undesired currents referred to are eliminated in a different manner.
  • a transformer 20 provided in the ground connection at end 3hy means of which a current of the desired value and phase relation may be impressed upon the receiving apparatus to neutralize the effect of the undesired currents in the receiving apparatus.
  • the magnitude of this current may be adjusted by varying the coupling of transformer 20 and the phase relation may be.
  • F shows an arrangement of a transl former or transformers adapted to the case where the ratio of the desired signal current to currents produced by undesired influences is best at a point other than the end of the
  • the action of the transformer in this case would be the same in principle as the action of a similar transformer when located at the end of the antenna as ,indicated in Figs. 1 and 2.
  • Fig. 5 shows still another arrangement of transformers by which currents flowing over the two wires of the antenna in multiple may be made to induce currents which will flow through the two wires in series.
  • an in- .duced current will flow from right to left in making it possible to perform the transformation at the best point for the reception of a particular signal, while' for'another signal of different wave length the trans.- formation may be performed at a different point on theantenna.
  • One antenna which I have found suitable for carrying out my invention consists of a pair ofwires about 14,000 meters long' carried by poles approximately feet high. By the use of this antenna I have obtained very satisfactory results in the reception of signals varying-in wave length from about 10,000 meters to 23,000 meters and these results have been obtained with the receiving station located at the end of the antenna nearest the transmitting station as well as at intermediate points along the length of the antenna.
  • a receiving system for radio signals comprising a long horizontal receiving tenna comprising a pair of conductors, and means for utilizlng said pair of conductors as the two sides of a circuit for conveying signaling currents from a selected point in said antenna to a distant receiving station located along the length of said antenna.
  • a receiving system for radio signals comprising a long. horizontal receiving antenna and'means for utilizing said antenna as a transmission line for conveying signaling-currents from the end of said antenna wher'e signaling currents received on the antenna from a desired station are strongest to a distant receiving station located along-the length of said antenna.
  • a receiving system for radio signals comprising a long horizontal receiving antenna and means .for utilizing said antenna as a transmlssion l1ne for conveymg s1gnaling currents from the end of said antenna where signaling currents received on.
  • a receiving system for radio signals comprising a long horizontal receiving an-' tenna comprising a pair of conductors, and
  • receiving station 10- c-atedalong the length of said antenna.
  • a receiving system for radio signals comprising'a long-horizontal receiving antenna comprising a pair of conductors, and
  • a receiving system for radio signals comprising a long horizontal receiving antenna and means for utilizing said antenna as a transmission line for conveying signaling currents from a selected point in said antenna where signaling currents received on the antenna from a desired station are strongest to a distant receiving station located along the length of said antenna, and means for eliminating in the receiving apparatus the effect of currehtsproduced in said antenna at the selected point by waves. coming from a different direction from that of the desired signaling waves.
  • a receiving system for radio signals comprising a long horizontal receiving antenna comprising a pair of conductors
  • a receiving system for radio signals comprising a long horizontal receiving anconnection for both conductors of the antenna and the secondary windings being connected in series in a circuit which includes the two conductors of the pair in se-i ries, the common ground connection being made to an intermediate point m-the secondary windings.
  • a receiving system for radio signals comprising a long horizontal receiving antenna comprising a pair of conductors, ground connections for said antenna at both ends and a transformer system at the end'of said antenna'where signaling currents from a desiredstation are strongest,'the primary windings of said transformer system being emes connected in series in the common ground connected in series in a circuitwhich includes the two conductors of the pair in series, and a second transformer system at a point distant from the first pair having its prlmary windings connected in series in said circuit and its secondaries connected to a receiving apparatus in such a way that the receiving apparatus will be influenced by currents flowing in opposite directions along the length of the two conductors but will be unaffected by currents flowing in the same direction in the two conductors.
  • a receiving systemfor radio signals comprising a long horizontal receiving antenna comprising a pair of conductors, ground connections for said antenna at both ends and a transformer system at the end of said antenna where signaling currents from a desired station are strongest, the primary windings of said transformer system being connected in series in a circuit which includes the two conductors of the pair in series, the common ground connection being made to an intermediate point in the secondary windings, and a second transformer system at a point distant from the first pair having its primaryv windings connected in series in said circuit and its secondaries connected to a receiving apparatus in such a way that the receiving apparatus will be influenced by currents flowing in opposite directions along the length of the two conductors but will be unafiected by currents flowing in the same direction in the two conductors.
  • A- receiving system for radio signals comprising a long horizontal receiving antenna comprising a pair a of conductors, ground connections for said antenna at both ends and a transformer system at the end iii of said antenna where signaling currents from a desired station are strongest, the primary windings of said transformer system being connected in series in the common ground connection for both conductors of the antenna and the secondary windings being connected in series in a circuit which includes the two conductors of the pair in series, and a second transformer systemat the other end of said antenna having its primary windings connected in series in said circuit and its secondaries connected to a' receiving apparatus in such a Way that the receiving apparatus will be influenced by currents flowing in opposite directions along the length of the two conductors but will be unaffected by currents flowing in the same direction in the two conductors.
  • 13.-A receiving system for radio signals comprising a long horizontal receiving an tenna comprising a pair of conductors, ground connections for said antenna at both ends and a transformer system at the end of said antenna where slgnaling currents from a desired station are strongest, the primary windings of said transformer system being connected in series in the common ground connection for both conductors of the antenna and the secondary windings being connected in series in a circuit which includes the two conductors of the pair in series, the common ground connection being made to an intermediate point in the secondary windings.
  • a second transformer system at the other end of said antenna having its primaries connected in series in said circuit and its secondaries connected to a receiving apparatus in such a way that the receiving apparatus will be influenced by currents flowing in opposite directions along the length of the two conductors but will be unaffected by currents flowing in the same direction in the two'conductors.
  • a receiving system for radio signals comprising a long horizontal receiving antenna comprising a pair of conductors, ground connections for said antenna at both ends and a transformer system at the end of said antenna where signaling currents from a desired station are strongest, the primary windings of said transformer system being connected in series in the common ground connection for both conductors of the antenna and the secondary windings being connected in series in a circuit which includes the two conductors of the pair in series, and a second transformer system at the other end of said antenna having its primary windings connected in series in said circuit and its secondaries connected to a receiving apparatus, the ground connection at the receiving station being made to an intermediate point in the primary windings so that the receiving apparatus will be influenced by currents flowing in opposite directions along the length of the two conductors but will be unaflected by currents flowing in the same direction in the two conductors.
  • a receiving system for radio signals comprising a substantially, horizontal receiving antenna which has a ground connection atone end including a resistance substantially equal to the surge impedance of said antenna, and a series tuned circuit in series withsaid ground connection.
  • a receiving system-for radio signals comprising a substantially horizontal receiving antenna'which has a ground connection at one end including a resistance substantially equal to the surge impedance of said antenna, and a series tuned circuit connectio 17.
  • a receiving system vfor radio signals comprising a substantially horizontal receiving antenna which is grounded at both and means for producing a desired reflection.
  • a receiving system for radio signals comprising a long horizontal receiving antenna and means for utilizing saidantenna as a transmission line for conveying signaling currents from the end of said antenna where signaling currents received on the antenna froin a desired station are strongest to a receiving station located at the other end of said antenna, and means at said other end of said antenna for preventing any undesired reflect-ion of electric waves traveling along said antenna and for producing a desired reflection.
  • a receiving system for radio signals comprising a long horizontal receiving antenna and means for utilizing said antenna as a transmission line for conveying signaling currents from a selected point in said antenna to a distant receiving station located along the length of said antenna, and means for eliminating in the receiving apparatus the effect of currents produced in said antenna by waves coming from a different '1 direction from that of the desired comprising a long horizontal receiving antenna compr sing a pair of conductors,-
  • the primary windings of said transformer system being connected in series in the comlmo-n ground. connection for both conductors of the antenna, and the secondary windings being connected in series in a circuit which includes the two conductors of the pair in said antenna where signaling currents from a desired station are strongest, the primary windings of said transformer system being connected in series in the common ground connection for both conductors of the an tenna and the secondary windings being connected in series in 'a circuit which in cludes the two conductorsof the pair in series, and a second transformer system at the other end of.
  • said antenna having its primaries connected in series in said circuit and its secondaries connected to a receiving apparatus in such a way that the receiving apparatus will be influenced by currents flowing in opposite directions along the length of the two conductors but will be unaffected by currents flowing in the same direction in the two conductors, the ground connection at the receiving station including means for preventing any undesired reflection of electric waves traveling along said antenna and for producing a desired rcflection.
  • a receiving system for radio signals comprising a long horizontal receiving antenna comprising a pair of conductors,-
  • ground connections for said antenna at both ends a transformer system at'tlie end of said antenna where signaling currents from a desired stationare strongest, the primary windings of said transformer system being connected in series in the common ground connection for both conductors of the antenna and the secondary windings being connected in series in a circuit which includes the two conductors of the pair in series, and a second transformer system at the other end of said antenna having its primary windings connected in series in said circuit and its secondaries connected to a receiving apparatus, the ground connection at the receiving station being made to an intermediate point in the primary windings so that the receiving apparatus will be influenced by currents flowing in opposite directions along the length of the two conductors but will be unaffected by currents flowing in the same direction in the two conductors, and including means for preventing any undesired reflection of electric waves traveling along said antenna and producing a desired reflection.
  • a radio receiving system comprising a longhorizontal antenna which consists in utilizing the an tenna as a transmission line for carrying signaling currents received from a desired station from a selected point in said antenna where such currents have a desired relation to other currents in the antenna to receiving apparatus located at a desired point along the length of said antenna, and at the same time preventing any appreciable change in tlie'desired'relation of the currents between the selected point and vthe point to which the signaling conveyed.
  • The'niethod of operating ta'radio receiving system comprising a long horizontal antenna which consists in transmitting to the receiving apparatus signaling currents currents are DCving system comprising a long horizontal antenna which consists in utilizing the antenna as a transmission line for-carryingsignaling currents received from a desired station from a selected point in said antenna where such currents have a desired relation to other currents in the antenna to receiving apparatus located a desired point along the length of said antenna, at the same time preventing any appreciable change 1n the desired relation of the currents between the selected point and the point to which the signaling currents are conveyed, and elimi-.-
  • A- receiving system for radio signals comprising a long horizontal receiving antenna-and means for utilizing said antenna as a transmission line-for conveying signaling currents from a selected point in said antenna where signaling currents received on the antenna from a desired station have a desired relation to other currents in the antenna to a distant receiving station located along the length ,of said antenna.
  • a receiving system for radio signals comprising a long horizontal receiving antenna and means for utilizing said antenna as a transmission line for conveying signaling currents from a selected point in said antenna where signaling currents received on the antenna from a desired station have a desired relation to other currents in the antenna, to a distant receiving station located along the length of said antenna, and means for eliminating in the receiving apparatus the effect of currents produced in said antenna at the selected point by waves coming from a different direction from that of the desired signaling waves.
  • a receiving system for radio signals con'iprising a long horizontal antenna and means for utilizing said antenna as a trans mission line for conveying signaling currents from a selected point in said antenna where signaling currents received on the antenna from a deslred station have a desired relation to other currents in the antenna to a distant receiving station located along the length of said antenna, and means for eliminating in vthe receiving apparatus the effect of currents produced in said antenna by waves coming from a different di-' 'rection from that 'of the desired signaling waves, said means comprising an arrangement for preventing any undesired reflection of electric waves traveling along said antenna and for-producing a desired reflection.
  • a receiving system for radio signals comprising a long horizontal receiving antenna and means for utilizing said antenna as a transmission line for conveying signaling currents from a selected point in said antenna where signaling currents received on the antenna from a desired station have a desiredrelation' to other currents in the antenna to a distant receiving station located along the length of said antenna, and means for preventn'ig any appreciable change in the desired relation of the currents between the selected point and the point to which the signaling currents are conveyed.
  • a receiving system for radio signals comprising a long horizontal receiving antenna and means for utilizing said antenna as a transmission line for conveying signaling currents from a selected point in said antenna where signaling currents received on the antenna from adesired station have a desired relation to other currents in the an tenna, to a distant receiving station located along the length of said antenna, means for eliminating in the receiving apparatus theeffect of currents produced in said antenna at the selected point by waves coming from a different direction from that of the desired signaling waves, and means for preventing any appreciable change in the desired relation of the currents between the selected 'point and the point to which the signaling currents are conveyed,
  • receiving system for radio signals comprising a long horizontal receiving an tenna and means for utilizing said antenna as a transmission line for conveying signaling currents from a selected point in said an tenna where signaling Currents received on the antenna from a desired station have a desired relation to other currents in the antenna to a distant receiving station located along the length of said antenna, means for eliminating in the receiving apparatus the effect of currents produced in said antenna by waves coming from a different direction from that of the desired signaling waves said means comprising an arrangement for desired characteristics for use in a receiving apparatus to a distant receiving station located along the length of the antenna.
  • a receiving system for radio signals comprising a long horizontal receiving antenna comprising a pair of conductors, and means for utilizing said pair of conductors as the two sides of a circuit for conveying currents produced in said antenna from a selected pointin said antenna to a distant receiving station located along the length of said antenna.
  • a receiving system for radio signals comprising a long horizontal receiving antenna and means for utilizing said antenna as a transmission line for conveying currents produced in said antenna at one end where the currents transmitted have desired characteristics for use in a receiving apparatus to a distant receiving station located along the length of the antenna.
  • a receiving system for radio signals comprising a long horizontal receiving antenna and means for utilizing said antenna as a transmission line for conveying currents produced in said antenna at one end Where the currents transmitted have desired characteristics for use ina receiving apparatus to a distant receiving station located at the other end of said antenna.
  • a receiving system for radio signals comprising a long horizontal receiving antenna comprising a pairof conductors, and means for utilizing said pair of conductors as the two sides of a circuit for conveying currents produced in said antenna at one end where the currents, transmitted have desired characteristics for use in a receiving apparatus to a distant receiving station located along the length of the antenna.
  • a receiving system for radio signals comprising a long horizontal receiving antenna comprising a pair of conductors, and;
  • a receiving system for radio signals comprising a long horizontal receiving antenna comprising a pair of conductors, ground connections for said antenna at both ends and a transformer system at one end of said antenna, the primary windings of said transformer system being connected in series in the common ground connection for both conductors of the antenna and the secondary windings being connected in series in a. circuit which includes the conductors of the pair in series.
  • a receiving system for radio signals comprising a long horizontal receiving antenna comprising a pair of conductors, ground connections for said antenna at both ends and a transformer system at one end of said antenna, the primary windings of said transformer system being connected in series in the common ground connection for'both conductors of the antenna and the secondary windings being connected in series in a circuit which includes the two conductors of the pair in series, the common ground connection being made to an intermediate point in the secondary windings.
  • a receiving system for radio signals comprising a long horizontal receivi'ngantenna comprising a pair of conductors, ground connections for said antenna at both ends and a transformer system at one end of said antenna, the primary windings of said transformer system being connected in series in the common ground connection for both conductors of the antenna and the secondary windings being connected in series in a circuit which includes the conductors of the. pair in series, and a second transformer system at a point distant from the first transformer system having its primary windings connected in series in said circuit and its secondary windings connected to a receiving apparatus in such a way as to impress thereon currents flowing in .opposite directions along the length of the two conductors without impressing thereon currents flowing in the same direction in the two conductors.
  • a receiving system for radio signals comprising a, long horizontal receiving antenna comprising a pair of conductors, ground connections for said antenna at both ends and a transformer system at one end in said circuit-and its secondary windings of said antenna, the' primary windings of connected to a receiving apparatus in such a said transformer system being connected in way as to impress thereon currents flowing series in the common ground connection for in opposite directions along the length of 5 both conductors of the antenna and the secthe two conductors without impressing 1 ondary windings being connected in series in thereon currents flowing in the same direca circuit which includes the conductors of tion in the two conductors. the pair in series, and a second transformer In witness whereof, I have hereunto set system at the other end of said antenna havmy hand this 18th day of J any., 1921.

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  • Variable-Direction Aerials And Aerial Arrays (AREA)
US438544A 1921-01-20 1921-01-20 Radio signaling system Expired - Lifetime US1487339A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
US438544A US1487339A (en) 1921-01-20 1921-01-20 Radio signaling system
FR25944D FR25944E (fr) 1921-01-20 1922-01-18 Perfectionnements aux postes radio-récepteurs
NL14381D NL14381C (fr) 1921-01-20 1922-01-19

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US438544A US1487339A (en) 1921-01-20 1921-01-20 Radio signaling system

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US1487339A true US1487339A (en) 1924-03-18

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US438544A Expired - Lifetime US1487339A (en) 1921-01-20 1921-01-20 Radio signaling system

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US (1) US1487339A (fr)
FR (1) FR25944E (fr)
NL (1) NL14381C (fr)

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NL14381C (fr) 1925-09-15
FR25944E (fr) 1923-06-22

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