US2929063A - Antenna - Google Patents

Description

March 15, 1960 J. D. LYNN, JR 2,929,063

ANTENNA Filed Dec. 7, 1954 2 Sheets-Sheet 1 Fig.3

Xmission L ine James 0. Lynn, Jr.

INVENTOR BY fiveMM/l ATTORNEY March 15, 1960 J. D. LYNN, JR

ANTENNA 2 Sheets-Sheet 2 Filed Dec. 7, 1954 James 0. Lynn, Jr:

INVENTOR ATTORNEY United States Patent ANTENNA James D. Lynn, Jr., OakRidge, Tenn. Application December 7, 1954, Serial No. 473,576

7 Claims. (Cl. 343-731) This invention relates to improvements in antennas and is particularly directed to a novel high gain directive antenna for the reception of UHF television signals.

The primary object of this invention is to modify the receiving characteristic'of a long wire antenna to provide a more unidirectional pattern in the direction of the signal source (transmitting station) and to narrow the frontal directivity pattern of the antenna; This is accomplished without changing the position of the receiving long wire with respect to the signal source by adding to the long wire to produce a longer and narrowerforward lobe and increased directivity. I

It is an accepted fact that the UHF signals at a distance from the signal source tend to be in layers of energy and in small areas or spots. By installing small high gain antennas in these live spots or areas, decent signals from the source can be received. However, under changes in weather conditions, a shifting of such live areas or spots results and it is, therefore, obvious that a considerable number of antennas would have to be scattered around to complement the shifting of the live spots or areas. Such a practice is not economically feasible. I i

From the standpoint of cost and pickup efficiency, a long wire antenna or combination of long wire antennas, such as the V configuration, is extremely reliable. However, such long wire antennas also have objectionable features and reception defects. For example, it is desirable that an antenna should have a very sharp pattern toward the signal source so as to prevent the pickup of ghost signals a'r'rivingfrom various directions; but,

the long wire antenna does not meet this requirement. The normal long wire antenna must also be very lon in order to have a very great gain. Thus, the main problem is one of overcoming the shortcomings of the long wire antenna so that it can be used to optimum advantage and such problem involves the reducing of the size of the antenna and the increasing of its directivity.

The present invention answers the problem by adding a half-wave antenna section to a long wire antenna to modify the receiving characteristic of the long wire by (1) providing a more unidirectional pattern in the direction of the signal source and (2) increasing the-strength or" this forward lobe by the addition of the half wave section in the forward direction. The addition of the half-wave section to a long wire antenna produces a longer forward lobe and a narrower forward lobe for the desired unidirectional characteristic and for increased directivity and a doubling of the gain. In the latter respect, the addition of the half-wave sections doubles the normal gain of such a long wire as normally used.

Thus, a further object of this invention is to provide a dependable, inexpensive and high gain antenna that is light Weight and has low wind resistance.

A further object of this invention is to provide an antenna that is easy to install in low signal areas and m m of the antenna of Figs. 3 and 4, and

2,929,063 Patented Mar. 15, 1960 has sharp directivity for the elimination of ghost and Spurious signal responses. I

These and ancillary objects are attained by this' invention, the preferred forms of which are described in the following and illustrated in the accompanying drawings, wherein: 4

Figure 1 is a top plan view of a single long wire antenna constructed in accordance with the of this invention;

Figure 2 is a perspective view thereof;

Figure 3 is a top plan view of a long wire antenna or V configuration;

Figure 4 is a perspective view thereof;

Figure 5 is a perspective view of a stacking arrange- Figure 6 is a perspective view of a variable indoor antenna.

Referring now more particularly to' the drawings and initially'to Figs. land 2 for an understanding of'the basic concept, it will be noted that a wavelength long wire antenna iii is illustrated. Such a long "wire ha -a directional characteristic by itself but is given unidirectional pattern, as illustrated in Fig. 1, by the addition of a /2 wave length section 12 to the outer end thereof. The /2 wave section 12 is integral with the the'stub 11 makes the antenna more usable for UHF because its eifects causes the antenna to cover a wider frequency range and eliminates the losses encountered with common insualtors at such frequencies.

The addition of the half wave section 12 modifies the radiation characteristic of the 1 wave long wire-10 to provide a more unidirectional pattern in the direction of the signal source (direction; of the arrow in Fig. 1) and to narrow the frontal directivity pattern of the antenna.

In Figs. 3 and 4, the basic concept is carried over to a long wire antenna of a. V configuration. The antennaofFigs. 3 and 4 includes'two waye long wire sections 13 and M which are arranged on a A wave supporting stub 15., Each of the long wire sections is. terminated by a /2 wave section 16 and 17. This arrangement are vides a highly directive high gain antenna. " sections 13 and 16 combine to provide astreng for-- ward lobe as explained in the discussion of Figure 1. Sections 14 and 17 also combine to provide similar characteristics. in attaching the two combinations at points 18 and 19 of A wave stub 15 and in the configuration shown in Fig. 3 there is provided a receivingsystern of appreciable. gain. Half-wave section 16 added to the wave long wire section 13 and /2 wave section 17 added to wave long wire section 13 and /2 wave section 17 added to wave section 14 combine to serve a'two fold purpose, one to intercept the received signals and tapered transmission line feeding the /2 wave sections 16 and 17 and as wave long wire terminated antennas. These characteristics contribute appreciably to the increased directivity, antenna gain and system gain.

principles as shown in Fig. 3. However, the pattern shown in Fig.

3 is only the horizontal pattern which is a cross section of figures of revolution about the line x. The bottom antenna section formed by elements 24, 25, 26 and 27 will 7 also, when alone, have the same characteristic of the top section and of the antenna as shown in Fig. 3.

When the top and bottom antenna sections or assemblies are combined as shown in Fig. 5, the elements cause the vertical components to add and form a narrow direc tive beam similar to the horizontal beam. This counteraction of energy in one direction provides a gain.

I In Fig. 6, an indoor assembly is shown, which is compact and'small and has high gain and excellent directivity. The antenna of Fig. 6 may he used on top of a television set or in an attic installation and also may be used outdoors when properly mounted on a mast. The telescopic sections 28 and 29 serve the same purpose and will exhibit the same characteristic as the long wire wave sections on the other assemblies (Figs. 1-5) with the exception that the length of the sections 28 and 29 is made variable in order that operation for any frequency in the UHF band can be optimized. The sections 30 and 31 serve the same purpose as the /2 wave sections in the other assemblies except that they are pivotally attached to variable sections 28 and 29 for the purpose of varying the angle therebetween to achieve optimum operation over the UHF band. The M: wave stub 32 is supported by a stand 33 and carries a movable shorting bar 34. The M4 wave stub in conjunction with the movable shorting bar 34 provides facilities for matching the antenna impedance over the entire UHF frequency range. The position of the shorting bar on the A- wave stub 32 determines the impedance across feed points 36 and 37 and proper adjustment of the bar will provide a good impedance match at any specific frequency. Adjustment of the other elements, that is, pivotally swinging of the variable elements and the A wave sections and axial adjustment of the variable sections 28 and 29, will provide directivity and gain at any given frequency in the UHF band. The antenna assembly exhibits ideal property for indoor use.

as coming within the scope of the invention defined by the appended claims.

I claim:

1. In a high frequency antenna, a long conductor wire, a quarter wave stub connected to the inner end of said long wire and constituting a support, and a half wave length wire connected to the outer terminal of said long wire and extending at an angle thereto.

2. In a high frequency antenna, a U-shape quarter wave stub, a pair of long conductor wires connected at one end to the stub and extending therefrom in the form of a V and half wave length wires extending from the outer terminals of said long wires in a direction towards each other.

3. In a high frequency antenna, a U-shape quarter wave stub, a pair of long conductor wires connected at one end to the stub and extending therefrom in the form of a V and half wave length wires extending inwardly from the terminals of said long wires at an acute angle thereto.

4. Ina high frequency antenna, a quarter wave stub, pairs of long conductor wires connected at one end to said stub, each pair being arranged in the form of a V with one pair in superposed spaced relation to the other, and half wave length wires extending inwardly from the terminal ends of said pairs of long conductor wires.

5; In a' high frequency antenna, a quarter wave stub constituting a support, a pair of axially extensible conductor wires connected at one end to said stub, and half wave length wires connected to the terminal ends of said extensible conductor wires and extending inwardly in the direction towards each other.

and shown herein but that other forms may be realized I j 6. In a high frequency antenna, a quarter wave stub constituting a support, a pair of axially extensible conductor wires pivotally connected at one end to the terminals of said stub and extending therefrom in the form of a V, half wave length wires pivotally connected to the open ends of said extensible wires and a shorting bar movably carried by said stub.

'7. In ahigh frequency antenna, a quarter wave stub constituting a support, a long conductor wire connected at one end to said .stub and extending angularly therefrom in the direction of the signal source, and a half wave conductor wire connected to the open end of said long wire and extending'at an acute angle thereto.

References Cited in the file of this patent UNITED STATES PATENTS.

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