WO2013150434A1

WO2013150434A1 - Coupling device for coupling a parabolic antenna to an equatorial mount of an apparatus adapted for receiving radio waves, particularly a radio telescope, and apparatus for receiving radio waves provided with such device

Info

Publication number: WO2013150434A1
Application number: PCT/IB2013/052552
Authority: WO
Inventors: Filippo BRADASCHIA
Original assignee: Bradaschia Filippo
Priority date: 2012-04-02
Filing date: 2013-03-29
Publication date: 2013-10-10
Also published as: ITPN20120017A1

Abstract

The present invention refers to a device for coupling a parabolic antenna (2) to an equatorial mount (3) comprising a first counterweight (8) arranged to balance the parabolic antenna (2) about a first axis (X); the coupling device (4) comprising a plate (10) to which is slidably associable a second counterweight (12) selectively adjustable and fixable along the plate (10) for balancing said parabolic antenna (2) about a second axis (Y) perpendicular to said first axis (X). The invention also refers to an apparatus for receiving radio waves, particularly a radio telescope, provided with said coupling device.

Description

"COUPLING DEVICE FOR COUPLING A PARABOLIC ANTENNA TO AN EQUATORIAL MOUNT OF AN APPARATUS ADAPTED FOR RECEIVING RADIO WAVES, PARTICULARLY A RADIO TELESCOPE, AND APPARATUS FOR RECEIVING RADIO WAVES PROVIDED WITH SUCH DEVICE- DESCRIPTION

TECHNICAL FIELD OF INVENTION

The present invention refers to a device for coupling a parabolic antenna to an equatorial mount of an apparatus for receiving radio waves, in particular for application to a radio telescope. The invention also concerns an apparatus for receiving radio waves provided with said device.

BACKGROUND OF THE INVENTION

As is well-known, a radio telescope is an instrument that makes it possible to pick up radio waves emitted by objects present in the universe.

The amplitude of the range of radio waves makes it possible to observe and study objects that are very different from each other, but requires at the same time different instruments in order for it to be analyzed altogether.

Radio telescopes are essentially made up of three parts: the antenna, generally of parabolic type, the receiver and the mount. The antenna is a device that converts electromagnetic radiation into an electrical current that is then sent to the receiver. The mount, in addition to connecting the antenna to the ground support structure, must be capable of providing the antenna with the functions of pointing and tracking the object to be observed.

The state of the art in radio astronomy is represented by the large professional telescopes located in well-defined places and provided with antennas having a diameter larger than several tens of metres to guarantee a good resolution and capacity to collect radio waves.

One drawback of the large radio telescopes lies in their high construction and installation costs, which can only be borne by government research bodies or large scientific organizations; for this reason, there are only few such units anywhere in the world.

On the other hand, there are solutions that foresee the use of systems derived from TV SAT converted into a system for the reception of radio waves from outer space. Examples of these proposals can be found in web sites such as: www.iaraqroup.org, www.radioastrolab.it, www.elexp.com.

Although they have a moderate cost, the use of such instruments is extremely limited to the observation of very few objects, such as the Sun and the Moon.

Another, more important limit of such solutions lies in the fact that the pointing and tracking of the object to observe must be made in a completely manual mode, with the consequent lesser precision; in fact, the antenna is generally fixedly supported on a tripod or a trestle.

A further drawback lies in the scarce firmness of the ground support structure, of the tripod or trestle type, which causes the instability of the antenna due to the small vibrations coming from the ground or from atmospheric agents; this instability further reduces the already limited precision in pointing the object to be observed and consequently of the radio signals received.

One still further drawback lies in the poor balancing of the antenna on the tripod or trestle support which allows only a fixed position of the antenna and precludes it from performing any tracking movement.

SUMMARY OF THE INVENTION

The main objective of the present invention is thus to design a device for coupling a parabolic antenna to an equatorial mount for a radio receiving apparatus, in particular a radio telescope, and an instrument for the reception of radio waves provided with said device, capable of overcoming the drawbacks of the prior art.

In the scope of the above objective, one purpose of the present invention is to design a coupling device that makes it possible to couple a parabolic antenna to a mount of equatorial type, normally used for optical telescopes, capable of providing a high rigidity and stability, as well as balancing the overall unit.

Another purpose of the present invention is to develop a simple and economic coupling device that is also simple and easy to use, in particular for pointing and balancing the antenna.

A further purpose is to devise a coupling device that makes it possible to realize a radio waves receiving apparatus, in particular a radio telescope, of contained dimensions and costs to enable it to be commercially accessible, guaranteeing at the same time performance levels of good quality.

Another further purpose of the present invention is to develop an apparatus for receiving radio waves built with components that can be easily assembled and disassembled to be transportable. One not least important purpose is to devise a device for coupling a parabolic antenna to an equatorial mount for an apparatus for receiving radio waves, in particular a radio telescope, and an apparatus for receiving radio waves provided with said device, that achieve the above-mentioned objective and purposes at competitive costs and that can be manufactured with the usual and well-known machinery, systems and equipment.

The above objective and purposes, and others that will become more evident later in this description, are achieved by a device for coupling a parabolic antenna to an equatorial mount of an apparatus for receiving radio waves, in particular a radio telescope, as defined in claim 1 , and by an apparatus for the reception of radio waves provided with such a device as defined in claim 7.

BRIEF DESCRIPTION OF THE FIGURES

Further characteristics and advantages of the present invention will be more evident from the following description of a particular, but not exclusive, embodiment illustrated purely by way of non-limiting example with reference to the enclosed figures, wherein:

- figure 1 is an assembly drawing of an apparatus for the reception of radio waves, such as a radio telescope, comprising a device for coupling the antenna to an equatorial mount according to the present invention;

- figure 2 is an exploded view of the apparatus of figure 1 ;

- figure 3 illustrates the antenna and the device coupling device of the preceding figures;

- figure 4 illustrates the coupling device according to the present invention;

- figure 5 illustrates a detail of the antenna of the apparatus of figures 1 and 2;

- figure 6 is an assembly drawing of the apparatus of figure 1 seen from a different angle;

- figure 7 is a detail of the apparatus illustrated in the previous figure.

DETAILED DESCRIPTION OF THE INVENTION

With reference to the previously mentioned figures, number 1 indicates an apparatus for the reception of radio waves, such as a radio telescope. In the following description, reference will be made to an astronomical radio telescope, although the apparatus can also be destined for other uses, such as to determine the chemo-physical characteristics of the atmosphere or to survey a specific geographical area for fire prevention purposes, by suitably varying the operating frequency of the receiver.

The radio telescope 1 comprises a parabolic antenna 2, a mount 3 of equatorial type a device 4 for coupling the antenna 2 to the mount 3 and a ground support structure 5, preferably of column type.

The antenna 2 of the radio telescope 1 must be pointed to the precise area, or region, of the sky in which the source of the radio waves to be studied is located. For the present application, the use of a mount 3 of equatorial type, commonly used in normal optical astronomy, is particularly advantageous, as it makes it possible to track for a long period and with a high level of accuracy, the radio source under observation, thanks to an axis of rotation of the mount itself, which corresponds to the celestial axis. Mounts of this type can be internally equipped with a computerized electronic system that makes their remote computer control possible.

For a correct operation, the equatorial mount 3 must however be balanced on its two operating axes and the use of an optical alignment telescope is preferably required for the initial procedure of calibration of the equatorial mount 3 on the sky, as will be explained in greater detail later.

The parabola of the antenna 2 can be of the solid type or have a perforated structure of the "mesh" type; for the present invention, it is preferable to have this second type of structure in order to limit weight; in fact, although they have a slightly lower gain than is the case with parabolas of solid type, the parabolas of mesh type have the advantage of being considerably lighter, and thus they are particularly suitable to be installed on equatorial mounts with automatic pointing and tracking functions. In fact, if with a solid-body parabola it would be impossible to have a diameter larger than 1 .2-1 .3 m with a mount capable of supporting a weight of 20-25 kg, with parabolas of mesh type it is possible to use parabolas larger than 2 m in diameter. There is also the possibility of installing in the focus of the parabola an antenna feed 6 with an amplifying unit 7 of LNB ("Low Noise Block Converter") type suitable for the specific operating frequencies of the mesh parabola and of the receiver.

The equatorial mount 3 is turnably associable to the support structure 5 so as to enable it to carry out the automatic functions of pointing and tracking the radio source; for this purpose, the mount 3 is power-driven and its movement is controlled through a push-button panel or a specific software for tracking an astronomical object. As mentioned earlier, in order to operate correctly, equatorial mounts require a balancing on two axes, defined as right ascension axis and declination axis, that are perpendicular to each other. The mount 3 is thus provided with a first counterweight 8 that is adjustable by sliding along a rod 9 projecting from the mount itself 3 and arranged substantially perpendicularly to the axis of the antenna parabola 2; the function of the first counterweight 8 is to allow the balancing of the parabola about a first axis X, which defines the right ascension axis. In the normal use of such supports for optical telescopes, consisting essentially of an elongate cylinder along a longitudinal axis, the balancing about a single axis, indicated with Y and defining the declination axis, is achieved by shifting the telescope along the first axis X.

The installation of a parabolic antenna 2 on an equatorial mount 3 of the above type causes, however, an unbalancing of the whole assembly as, because of the weight of the parabola due to the relatively large diameter necessary to guarantee the capacity to receive weak radio-astronomical signals, the centre of gravity of the assembly along the declination axis Y is moved forward toward the parabola. It is thus necessary to provide a balancing of the parabola on both the right ascension axis, or first axis X, performed by the first counterweight 8, and on the declination axis, or second axis Y, oriented perpendicularly to the first axis X; the balancing of the declination axis Y is achieved through a coupling device 4 capable of providing a high degree of rigidity and a perfect balancing of the parabolic antenna 2 on the mount 3 to obtain the correct automatic pointing and tracking of the radio source with the possibility of generating radio images of said radio sources.

The coupling device 4 according to the present invention comprises a plate 10 provided, at an end portion 10a, with suitable guide means 1 1 , advantageously made in the shape of slots, extending in a longitudinal direction of the plate 10.

A second counterweight 12 is slidingly associable longitudinally to the plate 10 in proximity of the guide means 1 1 so as to be selectively adjusted and fixed thereto through known removable fastening means such as screws, in a specific position along the end portion 10a of the plate 10. The second counterweight 12, arranged along the axis of the antenna parabola 2, performs in this manner the function of balancing the declination axis Y, also guaranteeing the requirements of stability and rigidity necessary to an apparatus for the reception of radio waves, such as a radio telescope.

At the other end portion 10b of the plate 10, opposite to portion 10a, is fastened a flange 13 to which can be connected the antenna parabola 2 through known fastening means.

For the purpose of further increasing the stability and rigidity of the assembly, two or more braces 14 extend advantageously from the plate 10; said braces are connected at one end, to the plate 10 and, at the opposite end, to the support elements 15 of the antenna parabola 2.

Advantageously, the equatorial mount 3 can include a finderscope device 16 that makes it possible to manually collimate the antenna 2 on the object to observe in order to initialize the observation and the subsequent automatic tracking of the object. The finderscope device 16, consisting of a telescope with a small magnification provided with specific support and tracking adjusting screws for the necessary collimation with the axis of the parabola, is associable to the rod 9, preferably protruding beyond the first counterweight 8, and is oriented along an axis parallel to the axis of the parabola of the antenna 2. The positioning of the finderscope device 16 on the end part of the rod 9 is particularly advantageous, as it makes it possible to place the device 16 in the vicinity of the periphery of the parabola, where the field of vision is better as it is not obstructed by the structural parts of the antenna 2. Moreover, the positioning of the rod 9 makes it possible for the finderscope device 16 to cooperate in balancing the parabola about a first axis X together with the first counterweight 8.

The coupling device 4 is mountable on the equatorial mount 3 by means of a clamp 17 associated to the mount 3 and is capable of slidably retaining the plate 10 through suitable fastening means such as tightening means 18.

From the above description, it is evident how the present invention achieves the initially foreseen purposes and advantages: effectively, a coupling device has been designed to make it possible to obtain an apparatus for receiving radio waves, in particular a radio telescope, through the combination of a parabolic antenna and an equatorial mount on which it is installed, normally used in the field of optical astronomy.

In particular, the coupling of an equatorial mount to a parabolic antenna obtained through the coupling device according to the present invention, possibly combined with a specific software for automatically pointing and tracking a radio source, makes it possible to obtain an apparatus for receiving radio waves that is extremely reliable and provided with the essential requirements of high rigidity, stability and excellent balance required for use not only for amateur and teaching purposes but also in the semi-professional or professional scientific field.

Further, the coupling device according to the present invention is extremely simple and of relatively compact dimensions, beside being simple and easy to use, in particular to adjust the pointing and balancing of the antenna.

A further advantage of the present invention is the possibility of providing an apparatus for receiving radio waves, in particular a radio telescope, having limited dimensions and cost to make it commercially available, guaranteeing at the same time an apparatus with a performance level of good quality.

One still further advantage of the apparatus realized according to the present invention lies in the easy assembly and disassembly of the basic components - antenna, mount, ground support - that allows, together with its compact dimensions, the transportability of the apparatus.

Naturally, the present invention is susceptible of numerous applications, modifications or variants without thereby departing from the scope of patent protection as defined in the independent claims 1 and 7.

Further, the materials and equipment used to realize the present invention, as well as the shapes and dimensions of the individual components, may be the most suitable for the specific requirements.

Claims

1. Coupling device for coupling a parabolic antenna (2) to an equatorial mount (3) comprising a first counterweight (8) adapted to balance said parabolic antenna (2) about a first axis (X), characterized in that said coupling device comprises a plate (10) onto which a second counterweight (12) is slidingly associable, said second counterweight (12) being selectively adjustable and fixable along said plate (10) for balancing said parabolic antenna (2) about a second axis (Y) perpendicular to said first axis (X).

2. Coupling device as in claim 1 , wherein said first axis (X) is arranged, in use, substantially parallel to the axis of the parabola of said antenna (2), and said second axis (Y) is substantially perpendicular, in use, to the axis of the parabola of said antenna (2).

3. Device as in clam 1 , wherein said second counterweight (12) is slidingly associable to said plate (10) at guide means (1 1 ) provided on an end portion (10a) of said plate (10), said guide means (1 1 ) extending along a longitudinal direction of said plate (10).

4. Device as in claim 3, wherein a flange (13) is provided at the other end portion (10b) of said plate (10) opposite said end portion (10a), said antenna (2) being attachable to said flange (13).

5. Device as in claim 1 , wherein said plate (10) is mountable to said equatorial mount (3) by means of a clamp (17) associated to said equatorial mount (3) and adapted to slidingly retain said plate (10).

6. Use of a coupling device (4) as defined in claim 1 for coupling a parabolic antenna (2) to an equatorial mount (3) to obtain an apparatus (1 ) adapted for receiving radio waves, particularly a radio telescope.

7. Apparatus adapted for receiving radio waves, particularly a radio telescope, characterized in that it comprises, in combination:

- a parabolic antenna (2) adapted for receiving radio waves;

- an equatorial mount (3) comprising a first counterweight (8) adapted to balance said parabolic antenna (2) about a first axis (X) arranged substantially parallel to the axis of the parabola of said antenna (2);

- a coupling device (4) for coupling said parabolic antenna (2) to said equatorial mount (3), said coupling device (4) comprising a plate (10) onto which a second counterweight (12) is slidingly associable, said second counterweight (12) being selectively adjustable and fixable along said plate (10) for balancing said parabolic antenna (2) about a second axis (Y) perpendicular to said first axis (X) and perpendicular to the axis of the parabola of said antenna (2).

8. Apparatus as in claim 7, wherein said parabolic antenna (2) has a perforated structure of the "mesh" type.

9. Apparatus as in claim 7, wherein said equatorial mount (3) is provided with a rod (9) protruding from said equatorial mount (3) and aligned with said second axis (Y), said first counterweight (8) being slidingly and selectively adjustable along said rod (9), said equatorial mount (3) further including a finderscope device (16) associable to said rod (9) and oriented along an axis parallel to said second axis (Y).

10. Use of an apparatus adapted for receiving radio waves, particularly a radio telescope, as defined in claim 7.