US2167774A - Multiple upsilon antenna suspension - Google Patents

Description

Aug. 1, 1939. H, PR TT 2,167,774

MUTIPLE V ANTENNA SUSPENSION Filed May 4, 1937 INVENTOR HARAFE V PEA T7 BY I ATTORN EY Patented Aug. 1 1939 MULTIPLE V ANTENNA SUSPENSION Haraden Pratt, Douglaston, N. Y., assignor to. Macka-y Radio & Telegraph Company, New York, N. Y., a corporation of Delaware Application May 4, 1937, Serial No. 140,582

'7 Claims.

The present invention relates to antenna arrays of the multiple V type, and particularly toport of a quadruple V array by means of only six poles or towers. Another feature is the support of such an array according to a simple arrangement which maybe readily laid out for various lengths and angles of antennae and which re--- quires only a short total length of inactive tension strands. The antenna array =supporting arrangement of the present invention has the further feature that the tension in the inactive supporting tension strands are maintained within reasonable limits and are for the most part not higher than the tension in the radiating con.-

ductors of the array itself, so that most of the lengths of connecting tension strands maybe constructed of the same material as the conducting wires of the antenna array itself, and so that insulators, coupling members, and poles of unusual strength will notbe required.

The arrangement of the present invention is especially intended for use with quadruple V antenna arrays in which the angle between the axis of the array and any of the arms of the component Vs is between five and thirty-five degrees, and particularly for arrays in which this angle is between fourteen and twenty-five degrees. In the description of the present invention it will be assumed that the various arms of the quadruple V are of equal length or of substantially equal length, since such an arrangement is usual in such multiple V arrangements. The present invention may best be understood by reference to the drawing which schematically represents a plan view of the essential conductors of the quadruple V array and the supporting arrangement for supporting such conductors in accordance with the present invention.

The points P, R, S, T, represent the vertices of the four individual V shaped antennae which 66 comprise the array. ThepointsA, B, C and D,

represent the ends of the arms of the corresponding Vs on one side while the points A, B, C and D, represent the corresponding ends of the arms on the other side. Assume that each of the four Vs of the array subtends the same central angle which is represented as 2W, the angle W representing the inclination of any one of the arms of the VS with respect to the principal axis of the array. Since all four conductors on one side of the array are parallel to one another the direction of any of the conductors may be called the conductor direction of that side of the V array. This conductor direction as well as the direction of the principal axis of the whole array will be used as reference direction for specifying the angular orientation of the various supporting strands later to be described.

According to the present invention the complete quadruple V array is supported from only six poles represented by the small circles I, 2, 3, 4, 5 and 6 adjacent points P, S, F, D, F and D. The vertex of the outermost V antenna I l-ZI is supported directly from pole l, similarly the second innermost antenna I 3-23 has its vertex supported directly from the pole 2. The vertices, R and T, of the other two antennae l2-22 and i424are supported from poles I and 2, respectively, by means of the transmission lines PR and ST which also serve to carry the power to or from the antennae I222 and |4-24. Although each of these transmission lines PR and S- T is represented by a single line it will be understood that they will ordinarily be twowire transmission lines and will preferably be constructed of'the same type of conductor as the radiating arms of the antennae themselves. In the preferred construction, in fact, these transmission lines are merely extensions of the antenna arms, and the two wires .are held closely adjacent to each other by insulators at the points R and T and at suitable intervals between these points and the poles l and 2. These transmission lines may be directly connected to antennae il-2l and l323 at the points P and S, or may be dropped down the poles alongside of similar transmission lines from the antennae l l-2'| and 5-23 so that the four transmission lines may be suitably interconnected below. Although as described, the transmission lines are preferably 0 from the vertices of the various antennae, or may be led down in any suitable manner.

The outer ends that is, the ends remote from the vertices of the VS of arms II, I2, I3 and I4, are supported as follows: The outer end of the conductor I4 is supported directly from pole 4. The outer end of conductor II is supported by tension strand I5 from pole 3. The outer end of conductors I2 and I3 are supported from junction points E and C of tension arcs I'I, I8 and I9, as shown, the end of conductor I3 being directly attached to this tension are at the point C, while the end of conductor I2 is supported from the point E of the tension are by means of tension strand I6. The tension arcI'I, I8, I9 is supported at points F and D from poles 3 and 4.

It is apparent that tension strands I5 and I6 are in line with the conductors II and I2,?or in other words these tension strands have a zero angle with respect to the conductor direction of the corresponding side of the V array. The angles which strands I'I, I8 and I9 make with this conductor direction are denoted by'X, Y and Z, respectively. Similarly it is apparent that the tensions fa and ch in strands I5 and I6 are equal to the tensions employed in the conductors- II and I2. Upon the assumption that the tensions in conductors II, I2, I3 and I4 are all equal and are represented by K, the tensions in strands I5 and IE will then be simply K. The tensions in strands IT, I8 and IQ of the tension arm will be denoted, respectively, by ed, cc and ef, respectively.

According to one feature of the present invention tensions (11, ch, cd, ce and ef are for the most part arranged to be not greater than K. Ac-. cording to the preferred arrangement all but one of these tensions are maintained equal to or less than K, the only tension which exceeds this value being tension cd in tension strand II. At the same time, however, the sum of the lengths of tension strands I5, IS, IT, I8 and I9 is kept at a minimum so as to minimize distortions of the radiation pattern or reception pattern, reduce parasitic losses and decrease the cost of the equipment, especially the cost of the insulators necessary for breaking up the tension strands into small non-oscillating lengths. In order to minimize the total footage of tension strands the location of poles 3 and 4 and the orientation I'I, I8 and I9 are so oriented that angle X will be substantially equal to angle W. I At the same time angle Z is arranged to be as large as it can practically be made without necessitating excessive tension in the tension strands I8 and II, this angle Z being in any case greater than twice angle X. In order to avoid too great tension in strands II and I8, the angle Z should not exceed the supplement of 3X and should preferably be somewhat lower.

In the preferred arrangement angle Z equals 90 minus X, the angle Y equals 2X and the tensions in strands I9, I8 and II are, respectively, .7 K, K and 1.9 K approximately. Such a value of Z enables the same type of wire to be used for tension strands I8 and I9 as for tension strands I5 and I6 when these strands I5 and I6 are just safely strong enough to support the tension K. With this arrangement it is preferred to make all the tension strands excepting II of the same type .of wire as the conductorsII, I2, I3 and I4. The

, making Z and Y equal, in which case each of these angles will have a tangent which is three times as great as the tangent of X. In this case the tension in strands I8 and I9 will be about three fourths of K-and the tension in strand I'I willonly be 1.6 K.

It will be noted that when X is equal to W as above described, strand I9 is exactly perpendicular to the principal axis of the array and strand I1 is parallel to this axis. This parallelism of strand H with respect to the axis is preferably maintained whatever valueis chosen for angle Z since this parallelism reduces the length of, inactive tension strands required, by eliminating tension strands between conductor I4 and pole 4, as well as eliminatingthe need of an extra tension strand between conductor I3 and point C of the tension arc. H

Not only does this reduce the total length of inactive tension strands employed, but also this parallelism of strand II simplifies the fittings and reduces the number of insulators required, as well as providing a very suitable and convenient layout.

The following numerical illustration of an antennaconstructed in accordance with my invention may beuseful' as a concrete illustration of how the above described rules are applied. The angle W is 20,the' total angle between the two conductor directions of the two arms of the V array being 40. The distance from P to R is 85 feet, from R to S '75 feet, and from S toT 85 feet. The conductors II, I2, I3, I4 are each somewhat more than 400 feet long, the conductors 2I, 22, 23 and24 being of this same length. Angle X is 20,,angle Y and angle Z are each 475. Each of the conductors II, I2, I3 and I4 is drawn up to a tension of 1000 pounds, the tension in strands I6 and I5 being, of'course, 1000 pounds also. The tensions in strands I8 and I9 are each equal to approximately 720 pounds; and the tension instrand I! is approximately 1600 pounds. The conductors II, I2, I3 and I4 are constructed of number fi copper coated, steel wire; and this same type of wire is employed for tension strands I5, I6, I8 and I9 Tension strand II which must withstand a somewhat higher tension is made of quarter-inch stranded wire rope. All these inactive tension strands I5, I 6, I1, I8 and I9 are.

broken up into short lengths by the insertion of strain insulators at suitable intervals, so as to prevent these strands from picking up appre polesdisposed along the axis of the array, two

other pairs of poles disposed symmetrically about said axis, each of said other pairs being in the vicinity of the arm ends of one side of said array, a tension are extending between the two poles of each such other pair, means for supporting the vertices of the four V antennae from said first pair of poles and means for supporting the arm ends of said four antennae from said other pairs of poles and the tension arc extending between them.

2. A supporting structure for an array of at least four V antennae comprising a first pair of poles disposed along the axis of the array, two other pairs of poles disposed symmetrically about said axis, each of said other pairs being in the vicinity of the arm ends of one side of said array, the direction of alignment of the two poles of each such other pair forming an acute angle with the axis of the array, a tension are extending between the two poles of each such other pair, means for supporting the vertices of the four V antennae from said first pair of poles and means for supporting the arm ends of said four antennae from said other pairs of poles and the tension arc extending between them.

3. A supporting structure for an array of at least four nested V antennae comprising a first pair of poles disposed along the axis of the array, means for supporting the vertices of the four antennae from said pair of poles, two other pairs of poles disposed symmetrically about said axis, each of said other pairs being in the vicinity of the arm ends of one side of said array, a tension arc extending between the two poles of each such other pair, and means attached at intermediate points of each of said tension arcs for supporting the outer ends of a plurality of the V antennae.

4. A supporting structure for an array of at least four nested V antennae, one being innermost, one outermost, and the other two intermediate the innermost and outermost, comprising a first pair of poles disposed along the axis of the array, two other pairs of poles disposed symmetrically about said axis, each of said other pairs being in the vicinity of the arm ends of one side of said V array with one pole of each pair closer the axis of the array than the other, a tension arc extending between the two poles of each such other pair, means for supporting the outer ends of the innermost and outermost V antennae from said other pairs of poles and meansattached at two intermediate points of each of said tension arcs for supporting the outer ends of the two intermediate V antennae, that section of each tension arc which lies between that pole of the associated pair which is closer to the axis of the array and that one of the intermediate points of the tension are which is nearest to said last mientioned pole being substantially parallel to the axis of the array,

5. A multiple array comprising at least four nested parallel V antennae, one being innermost, one outermost, and the other two intermediate the innermost and outermost, supporting means for the vertices of said antennae, supporting means on one side of the array comprising a pair of poles of which one is in line with the arm of the innermost V and the other is in line with the arm of the outermost V, supporting connections from each of said poles to the arm with which it is aligned, a tension arc extending between said pair of poles, supporting means from each intermediate antenna arm to an intermediate point on the tension are which is in line with said arms and on the other side of the axis of the array, a similar supporting arrangement for the ends of the antennae arms on said other side comprising a pair of poles, a tension arc and supporting means.

6. A multiple array comprising at least four nested parallel V antennae, one being innermost, one outermiost, and the other two intermediate the innermost and outermost, supporting means for the vertices of said antennae, supporting means on one side of the array comprising a pair of poles of which one is in line with the arm of the innermost V and the other is in line with the arm of the outermost V, supporting connections from each of said poles to the arm with which it is aligned, a tension are extending between said pair of poles, supporting means from each intermediate antenna arm to an intermediate point on the tension are which is in line with said arms, the angular direction of the successive segments of the tension arc being such that the tension in each of two segments of the tension arc is substantially equal to the tension in the antenna wires themselves, and on the other side of the axis of the array a similar supporting arrangement for the ends of the antennae arms on said other side comprising a pair of poles, a tension arc and supporting means.

7. A quadruple V array comprising a first, a second, a third and a fourth V of antenna wire parallelly disposed within one another in the order mentioned, a first and a second pole located adjacent the vertices of said first and third Vs respectively, supporting connections from said first pole to the vertices of said first and second Vs, supporting connections from said second pole to the vertices of said third and fourth Vs, a third pole located in line with but remote from one arm of said first V, a fourth pole located adjacent the end of the corresponding arm of said fourth V, a supporting connection from said third pole to the end of the corresponding arm of said first V, a connection from said fourth pole to the end of the corresponding arm of said fourth V, a tension arc connected between said third and fourth poles, a connection from an intermediate point of said are to the outer end of the corresponding arm of said third V, a connection from another intermediate point of said tension arc to the outer end of the corresponding arm of said second V, said last named connection comprising a tension strand, and another supporting arrangement for the other arms of said first, second, third and fourth Vs comprising two poles, a tension arc, and connecting means similar to the arrangement for supporting said first mentioned arms of said first, second, third and fourth Vs.

I-IARADEN PRATT.

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