US2411518A - Electromagnetic wave transmission system - Google Patents

Electromagnetic wave transmission system Download PDF

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US2411518A
US2411518A US482677A US48267743A US2411518A US 2411518 A US2411518 A US 2411518A US 482677 A US482677 A US 482677A US 48267743 A US48267743 A US 48267743A US 2411518 A US2411518 A US 2411518A
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antenna
frequency
wave
antennas
array
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Henri G Busignies
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International Standard Electric Corp
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International Standard Electric Corp
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S1/00—Beacons or beacon systems transmitting signals having a characteristic or characteristics capable of being detected by non-directional receivers and defining directions, positions, or position lines fixed relatively to the beacon transmitters; Receivers co-operating therewith
    • G01S1/02—Beacons or beacon systems transmitting signals having a characteristic or characteristics capable of being detected by non-directional receivers and defining directions, positions, or position lines fixed relatively to the beacon transmitters; Receivers co-operating therewith using radio waves
    • G01S1/08—Systems for determining direction or position line
    • G01S1/38—Systems for determining direction or position line using comparison of [1] the phase of the envelope of the change of frequency, due to Doppler effect, of the signal transmitted by an antenna moving, or appearing to move, in a cyclic path with [2] the phase of a reference signal, the frequency of this reference signal being synchronised with that of the cyclic movement, or apparent cyclic movement, of the antenna
    • G01S1/40—Systems for determining direction or position line using comparison of [1] the phase of the envelope of the change of frequency, due to Doppler effect, of the signal transmitted by an antenna moving, or appearing to move, in a cyclic path with [2] the phase of a reference signal, the frequency of this reference signal being synchronised with that of the cyclic movement, or apparent cyclic movement, of the antenna the apparent movement of the antenna being produced by cyclic sequential energisation of fixed antennas
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/10—Polarisation diversity; Directional diversity

Definitions

  • the present invention relates to electromagnetic wave transmission systems, and in particular to systems such as transmitter systems wherein a transmitted wave is characterized by having a spectrum of frequencies, the frequencies varying with different directions of propagation, and/or receiver systems wherein the frequency of a received wave may be translated to other frequencies depending upon the direction of wave propagation with respect to a receiving system.
  • the wave transmission systems provided for in the present invention are characterized by the fact that they not only permit the radiation of waves having frequencies dierent from the frequency of the oscillations which produce the waves, but also permit in the case of reception, a frequency translation of received waves whereby the frequencies of currents in the receiver circuits are different from those f observable in the vicinity ef the receiving equipment,'and to which the receiving antennas are tuned.
  • the transmission systems provided for in the present invention also comprise means for making the frequency of a transmitted wave dependent upon the angle of radiation from a transmitter on the one hand, and for making the frequency of a received wave on the other hand dependent upon the angle of incidence which the wave makes with a receiving system.
  • the processes for establishing wave transmission systems such as those defined above are such that the frequencies of the radiated or the received waves are different from those frequencies which are created in the circuits of the transmitting or receiving apparatus as the case may be, and vary in a manner dependent upon the direction of the propagated wave with respect to a predetermined axis of either a transmitting or receiving antenna array.
  • means may be provided at a transmitter for modifying the radiation from a group of transmitting aerials in such a way that the radiation successively has as a center, a different aerial of the group.
  • means may be provided at a receiver for successively intercepting energy from a different aerial of a group of receiving aerials.
  • the angular variation of phase, and consequently the variation in frequency, as well as the directivity of the aerial systems depends on the rapidity at which the aerials of a group of aerials successively perform their radiating or receiving function.
  • the transmission and reception features of my invention may best'be explained by rst considering the Doppler-Fizeau principle.
  • a radiating antenna moving through space at high velocity.
  • the result would be thatl a spectrum of waves-varying in frequency would exist in space.
  • the wave of maximum frequency would be in the direction toward which the antenna was moving and the wave of minimum frequency in the opposite direction.
  • the rate of angular frequency variation in azimuth would be dependent on the velocity of the moving antenna. If a receiver were suiciently selective, it could detect small frequency variations and therefore small angular variations.
  • nl the Wave frequency appearing at a receiving antenna will have been increased by n periods during the unit ⁇ of time. If the transmitting antenna had moved in the opposite dii rection or directly away from the receiving antenna, the wave frequency at the receiving antenna would have been decreased by n periods.
  • the equivalent of a rapidly moving antenna provides means for producing several novel communication systems, direction finding systems, beacons, etc.
  • direction finding systems wherein direction determination is effected by direction finders which select radio waves of one constant frequency as the result of the orientation of a directive aerial system
  • the equivalent of a. rapidly moving antenna Provides a means for determining direction by a selection of frequency.
  • transmission systems embodying an ⁇ an.. tenna having the above described characteristics several transmissions that are made on the same frequency but which come from different directions, or portions of a single transmission that arrive over different spacial paths, will appear to the receiver as if they had different frequencies, thus permitting the picking up and the selecting of these various transmissions according to their directions of propagation.
  • Fig. 1 is a schematic representation of a wave transmission system for illustrating a principle of my invention
  • Fig. 3 is a schematic circuit diagram illustrating the operation and energization of a transmitting antenna array inaccordancevvvth .my invention
  • Fig. 4 is a schematic circuit diagram of a portion of Fig. 3 modified for illustrating how the antenna system of my invention may be employed for the reception of radio waves;
  • Fig. 5 illustrates a series of electrical voltage waves for controlling and regulating the radiation from, orv in general the conditioning of, the various individual antennas of my antenna array;
  • Fig. 6 illustrates schematically a radio beacon system in accordance with my invention
  • Fig. 7 illustrates schematically a direction finding system comprising the wave transmission system in accordance with my invention
  • Fig. 8 is a block diagram illustrating a two course beacon comprising crossed antenna arrays:
  • Fig. 9rk is a block diagram illustrating a communication system for reducing the effects of fading in accordance with my invention.
  • Fig. l() is a block diagram illustrating a second type of communication system for reducing the effects of fading in accordance with my invention.
  • the transmitter 'I' and the receiver R represent a communication system.
  • the transmitter may be of any type and radiates a carrier wave represented by the reference character W.
  • 'Ihe receiver R may be of any type suitable for receiving the type of wave W and is assumed to be capable of moving at high velocity in the direction of the arrow which is at an angle 0 with the direction joining the transmitter and the receiver. If the angle 0 were zero and the receiving aerial were moved directly toward the transmitter, in a unit of time it would have travelled a distance nk and the received frequency would have been increased by n periods per second. On the other hand', if the receiving aerial had moved directly away from the transmitter, the frequency would have been diminished by n periods in a unit of time.
  • the received frequency would have been varied in a unit of time by the value 11T cos 0 Where T is the period of one oscillation. If the cosine of 0 were positive the frequency would have been increased and if the cosine of 0 were negative the frequency would have been increased.
  • the numerals l, 2, 3, l and 5. represent individual fixed aerials of a five aerial array.
  • a receivingy aerial 9 is located at a distance from the aerial array..
  • the separation of the aerials thereof. have been given predetermined valuesand for simplicity of discus-r sion the separation has been chosen as a quarter wavelength at the operating frequency. All of the aerials are conditioned so that they will radiate in phase for a predetermined time period 5 which will be further explained hereafter. Let us further assume that the magnitude of the radiated wave as radiated from a single antenna varies in accordance with the positive half of a sine wave and that no more than two adjacent aerials are radiating simultaneously.
  • antenna I is radiating a, wave of maximum amplitude and is represented by the vector V1.
  • V1 At the remote receiving aerial 9 the Vector of the received Voltage is represented by V2.
  • the phase relationship between V1 and V2 may be of any value whatsoever but I have illustrated them both as being in the same direction or phase which would correspond to the condition in which there were an even number of wavelength between the transmitting and receiving antennas.
  • the vector f the received voltage would be a maximum at the same time that the transmitter was radiating at maximum amplitude at some subsequent period, this period being equal to the time required by the radiated wave to travel between the transmitter and the receiver.
  • the radiation from antennas 2, 3, 4 and 5 is zero.
  • the radiation from each antenna is modulated in accordance with the positive half of a sine wave, the modulating waves for each antenna being displaced in phase by 90 for adjacent antennas.
  • the radiated wave from one antenna is a maximum
  • the radiated wave from an adjacent antenna is zero.
  • vectors Va and V4 represent the values of the radiated waves from antenna l and 2, respectively, as they would exist at a time equal to one-eighth of a cycle of the modulating wave following the time zero. This is equivalent to a 45 phase displacement of the modulating voltage.
  • the vector V1 would have decreased to a value of 0.707 of its original value.
  • Vector V4 would have increased from zero to a value of 0.707 of its maximum value.
  • FIG. 3 wherein I have illustrated my invention as embodied in a transmitter consisting of eight antennas in a lineal array together with control apparatus for their energization.
  • the antennas l, 2, 3, 4, 5, 6, l, and 8 are separated one from the other, a distance equal to one-quarter wave length of the frequency at which they are designed to radiate.
  • the complete array therefore covers a distance of one and three-quarters wave lengths. This spacing is by way of example only and other spacings may be employed as explained more fully hereinafter.
  • control device l0 Connected to antenna l is control device l0, which I have illustrated as a vacuum tube having a cathode, an anode, and three grid electrodes. Similar control devices Il to l1 are connected to antennas 2 to 8 respectively. Anode potential for the devices is derived from a source I8 illustrated as a battery. Choke coils 20 to 26 are connected between the antennas as illustrated in order to isolate the antennas for radio frequency currents. High impedance circuits could be employed in place of choke coils if desired. Choke coil 21 isolates the power supply from the antenna 8. A high frequency source is illustrated by the block 29. This source may be of any type suitable for delivering high frequency energy to the grids 30 to 31 of control devices i0 to I l respectively.
  • the voltages applied to grids 30 to 37 are in-phase one with the other and this condition may be o-btained, for example, by making the 'lengths of the transmission lines 40 to 41 all equal. If transmission lines are not employed for connecting the high frequency source to the grids of the control devices, other known forms of obtaining in-phase voltages may be employed. In .accordance with my invention as illustrated in Fig. 3, the antennas l to 8 are caused to radiate lsuccessively in the following manner.
  • a plurality of modulating sweep voltages operate on other grids associated with the control devices I0 to l'i in such a manner that the initiation of radiation in an antenna follows the initiation of radiation in an adjacent antenna by a time period equal to one-quarter cycle of the modulating sweep voltage.
  • Fig. 3 it is assumed that the initiation of radiation from antenna 2 follows the initiation of radiation from antenna l and that the initiation of energy in antenna 3 follows the initiation of energy in antenna 2 and so forth throughout the complete array.
  • modulating sweep voltages is used since these voltages determine the rapidity with which the antennas are energized in sequence.
  • the control circuits for controlling the initiation of radiation in the antennas are such that radiation takes place only during the positive halves of the modulating sweep voltage waves as will be more fully explained hereinafter.
  • not more than two antennas should radiate at the same time.
  • further blocking or conditioning control voltages are applied to an additional set of grids in control devices l to il.
  • rlhe conditioning voltages are applied to grids 50 to 51, and the modulating sweep voltages are applied to the grids 110 to 41 of the control devices I0 to l1 respectively.
  • Fig. I have illustrated the modulating sweep voltages by curves A, B, C, and D and the conditioning voltages by curves M, N, S, and T.
  • the lower portion of Fig. 3 illustrates in block diagram the manner in which all of the various modulating sweep voltages and the conditioning voltages are obtained. This portion of the diagram and the voltage curves of Fig. 5 are to be considered together.
  • a blocking voltage M of 25 kilocycles is generated in any convenient manner.
  • the oscillator 6i! represents the generator of this voltage.
  • a second blocking voltage N is obtained by passing the voltage M through phase shifter El wherein theY latter is retarded 90.
  • a third blocking voltage S isolo- ⁇ tained by shifting the phase of the voltage M by 180. This phase shift is accomplished by means of the phase shifter 62.
  • a fourth blocking voltage time sequence is obtained by passing the voltage M through phase shifter El wherein theY latter is retarded 90.
  • T is obtained by shifting the phase of voltage N 180 by the phase shifter 63.
  • phase Shifters are well known in the art and require no detailed explanation as to their operation.
  • the output of the oscillator is also passed through a frequency doubler B4 to form the modulating sweep voltage A.
  • the latter voltage is passed through a phase shifter 65 in which it is retarded to produce the voltage B and the voltage D is obtained by shifting the phase of B by the phase shifter 65.
  • Voltage C is obtained from voltage A by shifting the phase of the latter 180 by phase shifter El. It will be noticed in passing that the voltages resulting from the 90 phase Shifters are retarded rather than advanced.
  • Rectiers lll, l5, '16, and 'Il have been included in the connections leading to various grids of the control devices.
  • these rectiers are not absolutely necessary a1- though they introduce no harmful results. They, however, are desirable in certain instances as will be explained hereinafter.
  • the characteristics of the control devices of Fig. 3 are such that when the devices are conditioned for operation, the potential on the grids 40 to 4l are in effect biasingV the devices to cut-off, that is, current will flow in the various antennas only when the positive half cycles of the modulating voltages are applied.
  • the grids and cathodes are in eiect functioning as rectiiiers and therefore the additional rectiers l-ll merely constitute other rectiers in series.
  • control devices other than those illustrated in Fig. 3 which could be employed, for example, devices operating on the principle of balanced modulators. In control devices of this latter type the use of rectifiers in the position shown in Fig. 3 would usually be essential.
  • the negative halves of curves A, B, C and D have been shown in dotted lines to illustrate that these voltages are rectified.
  • , 92, 93 are placed between the blocking voltage sources M, N, S, and T and the grids 50-5 l 52-53, 541-55, and 55l respectively of control devices. These limiters limit the output voltage of the blocking voltages M, N, S and T to a value L illustrated by the dotted lines K in Fig. 5.
  • the purpose of the blocking voltages is to so condition the control devices that the latter will be free to operate and permit wave energy to radiate from the antennas at certain times, and to prevent radiation from the antennas at other times, all in accordance. with a predetermined
  • the control devices have characteristics such that the limited blocking or conditioning voltages in themselves contribute substantially nothing to the radiated wave energy.
  • the envelope of the modulated radiated wave is controlled substantially entirely by the modulating sweep voltages A, B, C, and D.
  • the limiters are employed to reduce the large voltage peaks of the blocking voltages which otherwise might produce deleterious radiation.
  • conditioning voltages could also be employed.
  • a substantially square voltage wave having the shape of the curve U as 9 shown in Fig. would be equally as eiective as the voltage M, N, S or T.
  • Voltage M is applied to grid 50 and voltage A is applied to grid 40.
  • the voltage M unblocks or conditions the device IIJ and the voltage A modulates the antenna current, the frequency of which is controlled by the high frequency voltage applied to the grid 30.
  • modulating voltage A is also applied to the grid 44 of device I4 which is associated with antenna 5 one wavelength away from antenna I, and in the absence of preventive means undesired radiation from antenna 5 would take place.
  • the blocking voltage S is applied to the grid 54 of the device Ill.
  • antenna 2 begins tc radiate since it is at this time that the modulating voltage B is rst applied to the grid 4I. At this time, an antenna I is radiating at maximum amplitude and antenna 2 is just beginning to radiate. None of the other antennas can radiate at this time since their associated control devices either blocked or the modulating waves have not as yet been applied to the grids of the control devices associated with these antennas.
  • Another one-quarter cycle later antenna 3 just begins to radiate due to the fact that modulating voltage C is just becoming positive and the control device l2 has been unblocked by voltage N which is also becoming positive. At this moment antenna 2 is radiating alone at maximum output antenna l having discontinued to radiate.
  • Another one-quarter cycle later antenna 4 begins to radiate and at this time antenna 3 is radiating at maximum output.
  • a source of voltage represented -by the block 80 for modulating the radiated current at, for example, a voice frequency.
  • This modulating voltage is impressed on the anodes of the control devices through the transformer 8l.
  • a frequency measuring device located at a distance to the right and in line with the antenna array of Figure 3 would respond not to the frequency ofthe high frequency source 29, but that frequency as modied by the frequency of the modulating sweep voltages.
  • the frequency of the source 29 would be increased by 50 kilocycles per second.
  • a receiver located at this distant point could therefore be made selective to this increased frequency and of course, with suitable detecting apparatus, would reproduce the modulation originally placed on the carrier wave by the source 80.
  • the required modulating sweep voltages are four in number and differ in phase by 90.
  • Other antenna spacing could also be employed.
  • the antenna spacing were made equal to one-third of a wave length, three modulating sweep voltages would be employed diiering in phase by 120.
  • the number of sweep circuit voltages required in any system is equal to the wave length of the high frequency source divided by'the spacing between the antennas as measured in wave length.
  • Fig. 4 I have illustrated a portion of a receiving antenna array similar in character to the transmitting array shown in Fig. 3. I have illustrated only two antennas and their associated apparatus in Fig. 4 in order to avoid unnecessarily complicating the gure.
  • antenna Ia is connected to ground through an impedance
  • the grids 30a and 3Ia of the two conditioning devices IIla and IIa are connected across the impedances I50 and I5I respectively. Modulating sweep voltages are applied to grids 40a and IIa and blocking voltages are applied to grids 50a and 5Ia. These voltages may be of the same type as illustrated by the curves of Fig.
  • the modulating sweep voltage A is applied to grid 40a
  • the modulating voltage B is applied to grid llla
  • the blocking voltage M is applied to grids 50a and 5Ia.
  • a system of this type is useful in providing the elect of a receiving antenna moving rapidly through space such as will be described later in connection with Fig. 10.
  • Fig. 6 I have illustrated a radio beacon formed by combining a wave propagation system such as shown in Fig. 3 with a non-directional antenna to form a composite radiating system.
  • the wave propagating system comprises an antenna array composed of eight separate antennas, a conditioning or control device connected to each antenna, a modulating sweep voltage generator and a blocking voltage generator such as are illustrated in Fig. 3.
  • the antennas and other associated conditioning and control means are illustrated in Fig.
  • the carrier wave is not of constant frequency for all directions from the array but varies from a maximum to a minimum value, the maximum value being in the direction in which the separate antennas are successively excited and the minimum value in the opposite direction.
  • a separate antenna is positioned near the antenna array and is separately excited at a frequency preferable between the maximum and l l minimumr frequencies of the carrier waves radi ated by the antenna array.
  • this separate antenna is shown as the block
  • the carrier wave from the array and from the separate antenna combine or interfere to form beats.
  • the frequency of a space wave from the array is F-i-f and in the direction shown by the arrow
  • the beat frequency in the direction of the arrow ll is and in the opposite direction it is 11/21.
  • the resulting beat frequencies at right angles to the array is in both directions.
  • is F+f cos 60 or lug
  • 04, would combine with the frequency the frequency of the wave radiated by the separate antenna
  • a direction along which the beat frequency is zero could be employed as a course of a radio beacon.
  • a direction along which the beat frequency is zero could be employed as a course of a radio beacon.
  • an airplane ying this course and having a receiver capable of receiving a band of frequencies F-i-f to F-f would indicate a zero beat while on the course, but a finite beat while off the course. Should the plane be off course, the pilot need only y in the direction of lower beat frequency to arrive on the course.
  • any beacon may easily be changed in accordance with my invention. All that is required is to vary the frequency the wave radiated by the yseparate antenna
  • the receiving antenna array is preferably mounted in a manner such that it may be rotated through 360 and is, therefore, capable of being orientated in any direction.
  • a signal wave is arriving. It may be arriving from any direction as illustrated in Fig. 7 by the several arrows marked F. Actually the received signal is arriving from only one direction and by rotating the receiving antenna array, this particular direction may be determined in the following manner.
  • a voltage from a modulating sweep voltage source is employed to sweep across the antenna conditioning means associated with the antenna array. Let the frequency of the sweep voltage source be f.
  • the apparent frequency in the circuits of the receiver associated with the antenna array is F-l-f. This presupposes, of course, that the direction in which the antennas of the array are successively conditioned to receive is toward the origin of the signal wave.
  • the frequency developed in the circuits of the array receiver will be F--f cos 0, 0 being the angle between the direction of the incoming signal and the direction of the antenna array.
  • the non-directional receiver H0 also receives the wave having the frequency F.
  • this frequency F is also modulated by the frequency f of the sweep voltage source with the result that a side band frequency F-i-f appears in the receiver output.
  • the carrier frequency F and the other side band F-f are suppressed.
  • the two frequencies F-i-f cos 0 from the array and F-l-J from the separate receiving antenna are combined and detected in a detector
  • This frequency may be employed to operate an indicator H3. It will be seen that when the direction of the incoming signal and the direction of the array coincide, the cosine of 0 is equal to one and the frequency for operating the indicator is equal to zero. Many forms of indication capable of indicating this condition of zero beat are known in the art.
  • a radio beacon system comprising two antenna arrays and their associated equipment positioned at right angles to each other.
  • the antennas of each array are excited in phase at the frequency F and are conditioned to radiate by modulating sweep voltage f.
  • An analysis, in accordance with methods dis- Y cussed in connection with Figs. 6 and 7, of the beat frequencies occuring at a distance from the antenna arrays will showthat there will be two directions,v 180 apart-in which the beati frequency will be zero.
  • the Wave propagating system illustrated in Fig. 8 would therefore be suitable for a two course beacon. Changing the modulating sweep voltage frequency of one of the arrays with respect to the modulating sweep voltage frequency of the other, will provide a means for changing the direction in which zero beat will occur and therefore a means for changing the direction of the courses.
  • Fig. 9 I have illustrated a communication system in accordance with my invention which provides a means for reducing the effects of fading at a receiver.
  • the variation in carrier wave frequency radiated at various angles to the antenna array occurred in the horizontal plane.
  • a wave of any given carrier frequency defines a cone of revolution with the axis of the cone coinciding with the direction of the array.
  • the frequency radiated from the antenna array of my invention varies in a vertical plane in the same manner that it does in a horizontal plane.
  • the direction in which the antennas of the array are successively energized is in the direction H.
  • Carrier waves having different frequencies will be radiated in the vertical plane. If the frequency at which each antenna of the array is excited is F, and the frequency of the modulating sweep voltage is .'f, as in the other illustrations herein given, the frequencies of the various waves in the vertical plane will be F-l-f cos where 6 is the angle between the horizontal and the direction in the vertical plane in which the carrier wave is propagated.
  • the antenna is connected to a broad band receiver 3
  • a plurality of frequency selectors are connected to the wide band receiver for selecting those carrier frequencies which preferably contain the most energy. In the gure, I have illustrated two selectors only namely 3I2 and 3
  • a detector shown as blocks 314 and SI5.
  • the detected outputs are combined directly and may be amplified in the amplifier illustrated as block Slt.
  • the output of SES represents the desired signal.
  • Fig. 10 I have illustrated a second type of communication system employing the principle of an antenna moving rapidly through space.
  • the antenna array in Fig. 10 is employed at the receiver.
  • a transmitting antenna 400 is assumed to be transmitting a voice modulated carrier wave to the receiving system All).
  • the carrier wave may take a plurality of paths, the wave along each path being reflected in the upper atmosphere, and arriving at the receiving system at various vertical angles.
  • the carrier waves are all of the same frequency in distinction to their having different frequencies as described in connection with Fig. 9.
  • the conditioning devices and control circuits therefore are illustrated by the block 4i l. All of the frequencies developed are passed to a wide band amplifier illustrated by the block 412. Fromthe wide band amplifier connections are made to a plurality of frequency selectors illustrated by the blocks M3, lllll, M5, and M6.
  • each selector is connected a separate detector illustrated by the blocks 523, 624, 425, and Q25.
  • the outputs from the detectors are directly combined in a combining device G21.
  • the output from the combining device represents the signal.
  • the selecting devices 443 to M6 select those frequencies which contain the most energy and this may be accomplished by connecting to the wide band amplifier a scanning frequency receiver illustrated by block 428.
  • the output of the scanning frequency receiver is connected to a cathode ray oscillograph 429 which will show all of the frequencies developed from the carrier wave by the receiving antenna,
  • This method of overcoming fading is distinctly different from methods employed in the prior art which make use of either a plurality of antennas geographically spaced or of very sharp directive receiving systems.
  • any transmitter employing the principles of my invention radiates waves the source of which is very difficult to locate by triangulation methods.
  • a direction finding system located at a distance from the source of waves will respond only to a particular frequency depending on the angle between the direction of propaga'- tion of the waves and the direction of the antenna array producing the waves.
  • the direction finder can only determine the line of propagation of the received waves.
  • another direction finder must also determine the direction of wave propagation of the received waves with respect to its position.
  • the two direction finders although taking bearings on the same wave source, are actually receiving waves of different frequencies and unless some characteristic modulation is present in the waves, it will be difficult for said direction finders to be sure that they are triangulating on the same wave source.
  • An antenna Vsystem comprising a plurality of antennas arranged in a predetermined array, each of said antennas having substantially the same radiation pattern, and antenna conditioning means connected to said antennas to condition the same for successive wave translation in a manner simulating the effect of a single antenna together with its radiation pattern moving through space.
  • a wave translating system comprising a plurality of antennas arranged in a predetermined array, each of said antennas having substantially the same radiation pattern, antenna conditioning means connected to each antenna for conditioning said antennas to operate successively for wave translating purposes, and control means for timing the operation of said conditioning means to initiate the conditioning of one of said antennas while discontinuing the conditioning of another of said antennas.
  • a directional wave propagating system for a predetermined wavelength comprising a .plurality of antennas arranged in a predetermined array, a high frequency power source, said antennas being spaced apart a distance equal to a predetermined fraction of the wavelength corresponding to the frequency of said source, wave generating means including a power supply means connected to each of said antennas for energizing same at predetermined time intervals, means connecting said source to said generating means for conditioning said generating means to generate in-phase energy at said yfrequency, and control means connected to said generating means for timing the radiation of said in-phase energy whereby each antenna radiates successively at said predetermined time intervals to produce a wave in space having a length equal to said predetermined wavelength.
  • control means comprises a second Wave generating means having a frequency equal to the difference in frequency between the frequency corresponding to said predetermined wavelength and the frequency of said power source.
  • a directional wave propagating system for a predetermined wavelength comprising a high frequency power source, a plurality of subordinate antenna arrays, each subordinate array comprising a plurality of antennas, the spacing Vof antennas in each subordinate array being the same, said subordinate arrays being arranged -in overlapping spaced relation -to form Aa lineal main antenna array, the antennas of the main array being spaced apart a distance equal to a predetermined fraction of the wavelength corresponding to the frequency of said Source, wave generating means connected to each of said antennas for energizing same at predetermined time intervals, means connecting said source to all of lsaid generating means for conditioning saidgenerating means to generate in-phase energy at said frequency, control means vconnected to said -generating means for timing the initiation of the radiation of said iii-phase energy and for determining said time interval, -said control means comprising a second wave generating means for generating a plurality -of out-of-phase voltages equal in number to the number of said sub
  • control means also comprises a wave blocking means, said blocking means comprising generating means for generating a second plurality of out-of-phase voltages, the phase relation between the firstnamed plurality of out-of-phase voltages and said second plurality of out-of-phase voltages being such that no more than a given number of said antennas are radiating simultaneously.
  • a wave propagating system comprising a plurality of antennas arranged in lineal array in a fixed direction and means for energizing said antennas successively whereby the frequency of a space wave varies directly as the cosine of the angle between the direction of said array and the direction of propagation of said space wave.
  • a wave propagating system comprising a plurality of antennas arranged in lineal array, and means for energizing said antennas in phase with a voice modulated high frequency wave successively one after the other, said means comprising a modulating sweep voltage generator and a blocking voltage generator, the phasing of said sweep voltage and said blocking voltage being such that the time-phase at which any two adjacent antennas are energized is substantially equal to the total variation in space-phase of a wave radiated oy any one of said antennas over a distance equal to the spacing between said adjacent antennas whereby a plurality of space waves of different carrier frequencies but having the same modulation are radiated in a vertical plane passing through said array.
  • a radio direction finding system comprising a rotatable group of antennas arranged in a predetermined array, antenna conditioning means connected to said antennas to condition said antennas for successive wave translation, a non-directional wave translating means, control means for timing the operation of said conditioning means and for modulating said non-directional wave translating means, combining means for combining the output of the first-named wave translating means and of said non-directional wave translating means, and an indicator connected to said combining means for indicating the direction of a received signal.
  • a radio beacon comprising a plurality of antennas arranged in a predetermined array, antenna conditioning means connected to said antennas to condition said antennas for successive wave radiation, control means for timing the operation of said conditioning means whereby a plurality of waves lof different frequencies are radiated from said array, the frequencies of said radiated waves varying as a function of the angle between the direction of said Yarray and the directions of propagation of said radiated waves, a separate antenna, means for energizing said separate antenna at a frequency such that the resulting radiated wave therefrom is equal to the frequency of one of the waves radiated from said antenna array.
  • a radio beacon comprising a rst wave transmitting system comprising a plurality of lantennas in lineal array, antenna conditioning means connected to said antennas to condition said antennas for successive wave radiation, control means connected to said conditioning means for timing the operation of said conditioning means to initiate the conditioning of one of the antennas while discontinuing the conditioning of another of the antennas, a second wave transmitting system comprising a plurality of antennas in a second lineal array, a second conditioning means connected to said antennas of said second array to condition the antennas of said second array for successive wave radiation, a second control means connected to said second conditioning means for timing the operation of said second conditioning means to initiate the conditioning of one of the antennas of said second array while discontinuing the conditioning of another of the antenna thereof, and a high frequency power source connected to both of said conditioning means for producing radiation from the antennas thus conditioned to produce interference patterns in space, said patterns having at least one direction in which the resultant radiated energy is substantially zero.
  • a wave communication system comprising a plurality of antennas arranged in lineal array, means for energizing said antennas in phase with a voice modulated high frequency wave successively one after the other, said means comprising a modulating sweep voltage generator and a blocking voltage generator, the phasing of said sweep voltage and said blocking voltage being such that the time-phase at which any two adjacent antennas are energized is substantially equal to the total variation in space-phase of a wave radiated by any one of said antennas over a distance equal to the spacing between said adjacent antennas whereby a plurality of space waves of different carrier frequencies but having the same modulation are radiated in a vertical plane passing through said array, a receiving system located at a distance from said antenna array, said receiving system comprising a receiving antenna and a receiver, said receiver having a plurality of frequency selecting means, each of said selecting means being tuned to select a different one of said space waves of different carrier frequency, separate detecting means connected to each selecting means for detecting said voice modulation and means to combine the output of said
  • a wave communication system comprising a transmitting antenna for transmitting a modulated wave having a single carrier frequency, a receiving system, said receiving system comprising a plurality of spaced antennas arranged in a predetermined array, antenna conditioning means connected to each antenna of said array for conditioning same to operate successively for wave translating purposes, control means for timing the operation of said conditioning means to initiate the conditioning of one of said antennas while discontinuing the conditioning of another of said antennas whereby said carrier Wave of single frequency is translated into a wave having a frequency spectrum, an amplifier connected to said antenna array for amplifying the energy in said frequency spectrum, a plurality of selector means connected to said amplifier for selecting from said wave having a frequency spectrum a plurality of Waves of different frequency, and detecting and combining means connected to each of said selector means for reproducing said modulation.
  • a Wave communication system in accordance with claim 14 further comprising a scanning frequency receiver and an oscillograph connected to said amplifier for determining the Waves having the maximum energy.
  • the method of reducing the effects of fading comprising transmitting wave energy in the form of a modulated carrier wave, said carrier Wave having a frequency which varies with the direction of wave transmission, making an energy collection of at least a portion of said Wave energy, selecting a portion of said collected energy, said selected portion having a plurality of predetermined frequen.. cies, and detecting and combining said selected portions to reproduce said modulation.
  • the method of reducing the effects of fading comprising transmitting wave energy in the form of a modulated carrier wave of single frequency, making an energy collection of at least a portion of said wave energy While simultaneously translating the single frequency of said wave portion to a frequency spectrum, selecting from said spectrum energy portions each having a predetermined frequency and detecting and combining said selected energy portions to reproduce said modulation.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Variable-Direction Aerials And Aerial Arrays (AREA)
US482677A 1942-05-27 1943-04-12 Electromagnetic wave transmission system Expired - Lifetime US2411518A (en)

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Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2481509A (en) * 1945-09-05 1949-09-13 Paul G Hansel Directional system
US2490050A (en) * 1945-11-07 1949-12-06 Paul G Hansel Navigation system
US2502131A (en) * 1947-03-20 1950-03-28 Int Standard Electric Corp Radio direction finder
US2521702A (en) * 1944-08-04 1950-09-12 Int Standard Electric Corp Radio navigational system
US2533229A (en) * 1947-06-25 1950-12-12 Jr Edward N Dingley Omnidirectional radio beacon
US2541125A (en) * 1946-10-02 1951-02-13 Int Standard Electric Corp Radio navigation system
US2547066A (en) * 1945-10-16 1951-04-03 Herbert M Wagner Beacon guide
US2648003A (en) * 1946-01-07 1953-08-04 Us Navy Vernier scanner
US2861264A (en) * 1955-04-12 1958-11-18 Itt Direction finder system
US3054105A (en) * 1956-06-02 1962-09-11 Int Standard Electric Corp Radio direction finding system
US3094697A (en) * 1960-04-27 1963-06-18 Int Standard Electric Corp Frequency modulated approach beacon
US3113286A (en) * 1961-03-06 1963-12-03 Norman B Miller Acoustical wave direction determining device
US3144649A (en) * 1958-07-16 1964-08-11 Int Standard Electric Corp Direction finder or omnirange beacon with wide-aperture antenna system
US3230501A (en) * 1962-10-31 1966-01-18 John J Yagelowich Scanned output line transducer
US3286262A (en) * 1963-03-13 1966-11-15 Int Standard Electric Corp Amplitude modulation radio beacon
US3316530A (en) * 1963-04-10 1967-04-25 Smith & Sons Ltd S Echo-sounding apparatus with stabilized narrow beam
US3412405A (en) * 1964-09-14 1968-11-19 Motorola Inc Side lobe response reducing system
DE1168982B (xx) * 1961-03-16 1973-10-04
US3845487A (en) * 1972-09-26 1974-10-29 U Lammers Radio direction finding system
US4106023A (en) * 1975-02-24 1978-08-08 Baghdady Elie J Navigation aid system
US20050043039A1 (en) * 2003-08-21 2005-02-24 Yoshiji Ohta Position detecting system, and transmitting and receiving apparatuses for the position detecting system

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1085929B (de) * 1956-05-19 1960-07-28 Standard Elektrik Lorenz Ag Verfahren zur Anschaltung eines Antennensystems an einen Peilempfaenger oder einen Funkfeuersender
DE1166298B (de) * 1960-04-27 1964-03-26 Standard Elektrik Lorenz Ag Leitstrahlfunkfeuer
DE1249362B (xx) * 1960-09-24
DE3027451A1 (de) * 1980-07-19 1982-02-11 Standard Elektrik Lorenz Ag, 7000 Stuttgart Antennenanordnung mit mehreren antennen

Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2521702A (en) * 1944-08-04 1950-09-12 Int Standard Electric Corp Radio navigational system
US2481509A (en) * 1945-09-05 1949-09-13 Paul G Hansel Directional system
US2547066A (en) * 1945-10-16 1951-04-03 Herbert M Wagner Beacon guide
US2490050A (en) * 1945-11-07 1949-12-06 Paul G Hansel Navigation system
US2648003A (en) * 1946-01-07 1953-08-04 Us Navy Vernier scanner
US2541125A (en) * 1946-10-02 1951-02-13 Int Standard Electric Corp Radio navigation system
US2502131A (en) * 1947-03-20 1950-03-28 Int Standard Electric Corp Radio direction finder
US2533229A (en) * 1947-06-25 1950-12-12 Jr Edward N Dingley Omnidirectional radio beacon
US2861264A (en) * 1955-04-12 1958-11-18 Itt Direction finder system
US3054105A (en) * 1956-06-02 1962-09-11 Int Standard Electric Corp Radio direction finding system
US3144649A (en) * 1958-07-16 1964-08-11 Int Standard Electric Corp Direction finder or omnirange beacon with wide-aperture antenna system
US3181159A (en) * 1958-07-16 1965-04-27 Int Standard Electric Corp Omnidirectional bearing system
US3094697A (en) * 1960-04-27 1963-06-18 Int Standard Electric Corp Frequency modulated approach beacon
US3113286A (en) * 1961-03-06 1963-12-03 Norman B Miller Acoustical wave direction determining device
DE1168982C2 (de) * 1961-03-16 1973-10-04 Abtastverfahren fuer funkpeiler
DE1168982B (xx) * 1961-03-16 1973-10-04
US3230501A (en) * 1962-10-31 1966-01-18 John J Yagelowich Scanned output line transducer
US3286262A (en) * 1963-03-13 1966-11-15 Int Standard Electric Corp Amplitude modulation radio beacon
US3316530A (en) * 1963-04-10 1967-04-25 Smith & Sons Ltd S Echo-sounding apparatus with stabilized narrow beam
US3412405A (en) * 1964-09-14 1968-11-19 Motorola Inc Side lobe response reducing system
US3845487A (en) * 1972-09-26 1974-10-29 U Lammers Radio direction finding system
US4106023A (en) * 1975-02-24 1978-08-08 Baghdady Elie J Navigation aid system
US20050043039A1 (en) * 2003-08-21 2005-02-24 Yoshiji Ohta Position detecting system, and transmitting and receiving apparatuses for the position detecting system
US7474256B2 (en) * 2003-08-21 2009-01-06 Sharp Kabushiki Kaisha Position detecting system, and transmitting and receiving apparatuses for the position detecting system

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Publication number Publication date
CH268059A (de) 1950-04-30
NL135042C (xx)

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