US2578961A - Radio-guiding system - Google Patents

Description

Dec. 18, 1951 c, ARIBERT 2,578,961

RADIO GUIDING SYSTEM Filed Jan. 12, 1949 osm PHASE REVERSER SCI LLATOR OSCILLATOR INVENTOR' PHASE RE CHARLES ARIBERT I, T

CILLATOR BY ATTORNEY Patented Dec. 18, 1951 RADIO-GUIDING SYSTEM Charles Aribert, Paris, France, assignor to Societe francaise Sadir-Carpentier, Paris, France, a corporation of France Application January 12, 1949, Serial No. 70,481 In France January 15, 1948 3 Claims. 1 r My invention relates to a radio-aligning system providing four alignment axes.

It is known that radio fields varying in percentage modulation have with reference to radio fields varying in field strength, general advantages that are derived from the fact that the carrier waves have an amplitude that is substantially independent of azimuth, whereby certain objectionable efiects that are produced through the operation of the anti-fading system of the receiver system, are removed.

The arrangement according to my invention is characterized by the use of four aerials, for instance four vertical dipoles or doublet antennas located at the apices of a square. The antennas located at the ends of each diagonal line of said square are fed by current of the same frequency, phase and amplitude and are similarly modulated. Furthermore only the side bands are transmitted. Each of these pairs of aerials is fed in phase opposition with reference to the other pair. Lastly a central aerial transmits a partly modulated wave having the same high frequency as the preceding aerials. This partly modulated wave is substantially in phase with that transmitted by one of the diagonal pair of aerials, the phase of the partial modulation being reversed as in the case of conventional radioaligning means at a predetermined rhythm, for instance dot-dash rhythm or the complementary rhythm, generally known as the an rhythm.

In accompanying drawings illustrating my invention by way of example in an entirely diagrammatic manner:

Fig. 1 shows the location of the aerials,

Fig. 2 illustrates the means for feeding the aerials.

Fig. 3 illustrates a modification in the arrangement of the aerials.

As shown in Fig. 1 the aerials l, 2, 3 and 4 are located at the apices of a polygon. As disclosed hereinabove, the aerials l and 3 are fed with currents of identical phases and the value of which is I1=I sin wt sin pt The high frequency wave transmitted has a frequency w and the modulation has a frequency p. It is apparent that only the side bands are transmitted. Similarly the aerials 2 and 4 are fed with identical currents having the value I2=I sin wt sin pt. It is apparent that the currents I1-I2 are identical and diifer only through their sign.

Lastly the central aerial 5 is fed with a current 2 [3:] sin wt (liK sin pt) the signs and being substituted for one another at the desired rhythm, say a dot and dash rhythm.

It is apparent that the current in the central aerial has the same frequency and phase as concerns its high frequency component and also, except for its sign, as concerns its modulating component as the current fed to the aerials at the four apices of the square.

Calculation shows readily that the component field of the aerials |'23--4- in a direction forming an angle 0 with the diagonal line l-3 is approximately equal except for a multiplying factor depending on distance, conditions of propagation, etc. to

Hs=sin wt sin pt cos 20 H=sin wt [1+sin ptUc; cos 20 k3)] (1) This leads to a value of the percentage of modulation that is equal to =7cz cos 20:!ca 2) It is thus apparent that the percentage of modulation of the field received along the direction 0 does not vary or more accurately it merely changes in sign without changing in absolute.

value when cos 20:0 which means It is thus apparent that the four half axes assume directions that are parallel with the sides of the aerial square l -23-4.

It is well known that the reception of such a field may be performed through a conventional receiver, say a receiver of the type used for broadcasting if the modulation is at audio frequency or else any other receiver that is well known per se, such receivers obviously not forming part of the present invention that covers only the production of the radio aligning means.

According to a modification, the reversal in phase, instead of affecting the modulated portion of the waves transmitted by the central aerial is performed on the feed of the two diagonal pairs of aerials. It is-immediately apparent that in this modification the coefficient 7a; of the relationship (1) retains the same sign while the coefiicient Icz of the same equation changes sign at each reversal: the Equation 2 is modified by way of consequence while the results obtained remain the same.

Fig. 2 illustrates a manner of feeding aerials assumed to be in the present case dipole antennas, to wit the dipoles |2-3-4 arranged at the apices of the square and a central dipole antenna 5. directly in parallel through the feeders IS and I9 starting from a central feeder 6. On the other hand the dipole antennas 2 and 6 are fed similarly by the feeders 26-2! fed in their turn by the same primary feeder 5 but with acrossin of the wires forming the feeders "2t and 2E which provides the desired phase opposition; the different feeders are adjusted so as to produce currents of equal amplitude in the four dipole antennas. As to the central aerial 5, it is fed through a separate feeder l.

An oscillator 8, the frequency of which is w, feeds high frequency current to both transmitters 9 and Ii! that are fed on the other hand by the oscillator I I with the modulating voltage having afrequency p.

As'disclosed hereinabove'the transmitter 9 produces a single sideband with suppression of the carrier wave whereas the transmitter l produces a wave that is partly modulated. The transmitter [0 includes furthermore means 22 for reversing the phase of the modulation at the desired rhythm.

In the modification disclosed hereinabove, said phase reversing means are incorporated to the transmitter 9. I I

Fig. 3 illustrates a further embodiment of the aerials; the transmitters 9 and i0 and oscillators 8 and H perform the same functions in this embodiment as hereinabove and provide the same currents. The aerial is fed in the same manner through the feeder 1 starting from thetransmitter [0; only the manner of feeding the aerials I2--3-'-4 is changed. The feeder 6 is subdivided and forms two feeders I2I3- that are fed in parallel. Each of these secondary feeders l2--l3 forms again two branches as shown, comprising the terminal feeders I4 and I5 on one hand and I6 and I! on the other. The leads of the feeders l1 and are crossed with reference to those of the feeders l4 and 16.. Furthermore, the leads of feeder I3 are crossed with reference to those of feeder l2. Obviously this arrange ment provides the same result, to wit, a feed in parallel of the dipole antennas l--3 and of the dipole antennas 2-4, the system of antennas I-3 being fed in phase opposition with reference to the system of antennas 24.

Obviously many details may be modified in the arrangement disclosed without widening unduly thereby the scope of the invention as defined in accompanying claims.

WhatI claim is: r l

1. Radio transmitting apparatus comprising four aerials positioned at the apices of a four sided polygon, radio apparatus for feeding the pair of aerials positioned at the ends of one di- The dipole antennas !-3 are fed agonal of said polygon with high frequency oscillations of predetermined amplitude, the wave length of said oscillations being on the order of the length of the longer diagonal of said polygon, apparatus for feeding high frequency oscillations of the same amplitude and same high frequency as said first mentioned oscillations to the other pair of aerials located at the ends of the other diagonal of said polygon, said oscillations fed to said last mentioned pair of aerials being of opposite phase from that of said oscillations fed to said first mentioned pair of aerials, an additional aerial located substantially at the center of said polygon, modulating apparatus for modulating the oscillations supplied to said four aerials at the same frequency, phase and amplitude, apparatus for feeding high frequency oscillations of the same frequency and phase of said first mentioned oscillations to said additional aerial, modulating apparatus for modulating the oscillations fed to said additional aerial, apparatus for periodically reversing the relative phase of said last mentioned modulating apparatus with reference to the phase of the modulations applied to the oscillations fed to said first mentioned pair of aerials to provide alternately phase coincidence and phase concordance between the phases of these last two modulations.

2. Radio transmitting apparatus comprising four aerials positioned at the apices of a four sided polygon, radio apparatus for feeding the pair of aerials positioned at the ends of one diagonal of said polygon with high frequency oscillations of predetermined amplitude, the Wave length of said oscillations being on the order of the length of the longer diagonal of said polygon, apparatus for feeding high frequency oscillations of the same amplitude and same high frequency as said first mentioned oscillations to the other pair of aerials located at the ends of the other diagonal of said polygon, said oscillations fed to said last mentioned pair of aerials being of opposite phase from that of said oscillations fed to said first mentioned pair of aerials, an additional aerial located substantiallyat the center of said polygon, modulating apparatus for modulating the oscillations supplied to said four aerials at the same frequency, phase and amplitude, apparatus for feeding high frequency oscillations of the same frequency and phase of said first mentioned oscillations to said additional aerial, modulating apparatus for partially modulating the oscillations fed to said additional aerial, and apparatus for reversing the phase of the currents fed to said additional antenna in accordance with a predetermined pattern.

3. Radio transmitting apparatus comprising four aerials positioned at the apices of a four sided polygon, radio apparatus for feeding the pair of aerials positioned at the ends of one diagonal of said polygon with high frequency oscillations of predetermined amplitude, the wave length of said oscillations being of the order of the length of the longer diagonal of said polygon, apparatus for feeding high frequency oscillations of the same amplitude and same high frequency as said first mentioned oscillations to the other pair of aerials located at the ends of the other diagonal of said polygon, said oscillations fed to said last mentioned pair of aerials being of opposite phase from that of said oscillations fed to said first mentioned pair of aerials, an additional aerial located substantially at the center of said polygon, modulating apparatus for modulating the 5 6 oscillations supplied to said four aerials at the REFERENCES CITED same frequency Phase and amplitude apparatus The following references are of record in the for feeding high frequency oscillations of the m of thi at same frequency and phase of said first mentioned e s p ent oscillations to said additional aerial, modulating 5 UNITED STATES PATENTS apparatus for modulating the oscillations fed to Number Name Date said additional aerial, and apparatus for period- 2,248,752 Goldman et a1. July 8, 1941 ically reversing the phase of the currents fed to 2,293,694 Alford Aug. 25, 1942 said first mentioned antennas in accordance with 2,414,431 Alford et al. Jan. 21, 1947 a predetermined pattern. 10 FOREIGN PATENTS CHARLES ARIBERT. Number Country Date 108,080 Australia July 21. 1939

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