RU215111U1 - ROLL TV ANTENNA - Google Patents

Abstract

The utility model relates to the field of radio engineering and can be used as a compact wide-range antenna, mainly a room window antenna, in television systems for receiving on-air digital television broadcasting signals in residential premises and structures, including summer cottages and on the windows of vehicles in parking lots. The technical result of the proposed utility model is to improve matching in an extended frequency band.

The roll television antenna includes a conductive receiving excitation element fixed or made on the surface of a substrate made of a thin dielectric material, the excitation points of which are connected through a matching device to connect the receiving equipment. The excitation receiving element is made of mainly conductive adhesive tape combined, in the form of a loop-vibrator with a dipole-vibrator located in parallel and connected via a symmetrical two-wire line, with a shunt connection through a delay device, with vibrator lengths commensurate with 0.5λ _cf. The dielectric substrate is made of a transparent rolled material, on which, along the axis of symmetry of the antenna in the zone of zero potential, there is a matching balancing device in the form of a coaxial power cable parallel to a two-wire line, which is connected by a central core and a braid to the excitation points, and the insulated surface of which starts from the position excitation points, covered with an additional braid, comparable in length to 0.25λ _cf. and connected by its end to the braid of the power cable and the central point of the dipole. 4 ill.

Description

The utility model relates to the field of radio engineering and can be used as a compact wide-range antenna, mainly a room window antenna, in television systems for receiving on-air digital television broadcasting signals in residential premises and structures, including summer cottages and on the windows of vehicles in parking lots.

The quality of the work of television receivers largely depends on the functional combination of television receivers and antenna devices, their purpose and location. On the one hand, the antenna must be adapted to the conditions of the electromagnetic environment at the installation site, and on the other hand, the comfort of its use should not be “limited” by its location.

For compact antennas, much should be minimized, but it is taken into account that the signal level depends on the distance to the TV tower and the direction of arrival of radio waves, the thickness of the walls and the height of the surrounding buildings, as well as the location of the premises and the environment with conductive elements that affect the reliability of television reception. As an alternative to the smaller classic room antennas used, window antennas are increasingly being used as internal antennas, which organically fit into any interior, in many cases when the TV towers are located on the exit side of the windows. In turn, in order to minimize the impact on the main function of the windows, so as not to reduce the luminous flux, such antennas are often made in the form of flat skeletal structures, with conductors placed on transparent substrates, and for temporary deployments they should be convenient for transportation.

The relevance and demand for such antennas is confirmed by a wide range of created window antenna devices from various manufacturers: Super Thin Indoor HDTV Antenna and HD Antena TV Fox Surf (https://www.joom.com/ru/products/6006b6ee3cl 8ee01068f7d43), REMO indoor active antenna " BAS-5326-5V" and REMO TV antenna "BAS-5322-USB DRAGONFLY" (https://remo-zavod.ru/antenny-televizionnye/).

Known antennas are almost identical and structurally have a combined receiving vibrator for the average frequency of the used radio wave lengths or a connection of several vibrators to separate frequency sections to expand the operating range and a balancing transformer to match the antenna amplifier.

The disadvantage of the known antenna devices is uneven in range and overestimated, with outrageous from standard, emissions of standing wave ratio (SWR) and low gain (KU), due to which the antennas are equipped with external power supply, antenna amplifiers, without which their performance is as broadband antenna devices is problematic.

The closest, the prototype, is the technical solution of the television antenna device (patent RU No. 76504 dated 20.09.2008, IPC H01Q 9/28. Bull. 26). The antenna includes at least one receiving excitation element fixed or made on the surface of a thin dielectric substrate, the excitation points of which are connected through a matching device through a connector with a power cable for connecting the receiving equipment.

The disadvantages of the prototype, despite the extreme simplicity of manufacturing flat dipole elements and low cost, is the need for an external matching device outside the main antenna structure and cable switching to it, the connector and further to the television receiver, as well as low KU and operation in a limited section of the radio wavelength range, not covering the frequency range of digital television broadcasting. In addition to this, to protect against external influences, the design of the antenna, in order to maintain electrical parameters, should mainly be placed in a dielectric housing made of a transparent material.

The objective (technical result) of the proposed utility model is to develop a technical solution for an antenna device with improved matching in an extended frequency band.

The solution of the problem is provided by the fact that in the antenna, which includes fixed or made on the surface of the substrate, implemented from a thin dielectric material, the conductive receiving excitation element is made combined from conductive adhesive tape. The excitation receiving element consists of a loop-vibrator with a dipole-vibrator located in parallel and connected, with vibrator lengths commensurate with 0.5λ _{cf. .} The vibrators are connected via a symmetrical two-wire line, shunted through a delay device. The excitation points of the conductive receiving element are connected by a power cable through a matching device to connect the receiving equipment. Moreover, the dielectric substrate is made of a transparent rolled material, on which a matching balancing device is located along the antenna symmetry axis in the zone of zero potential. The balancing device is made on the basis of a coaxial power cable parallel to a two-wire line, which is connected by a central conductor and a braid to the excitation points, and the insulated surface of the cable is covered with an additional braid. The braid originates from the position of the excitation points, commensurate in length with 0.25λ _cf. and is connected by the end to the braid of the power cable and the central point of the dipole, forming a balancing glass.

The delay device is made in the form of a lumped broken extension of the conductors of a symmetrical two-wire line, which can have from one to several bends.

The novelty of the proposed technical solution of the antenna in terms of the device is seen in the fact that the receiving excitation element is made combined, from dissimilar antenna elements, in the form of a loop vibrator and a classical dipole vibrator connected in parallel, with conductors located in the same plane.

The novelty of the device is seen in the fact that heterogeneous antenna elements in the form of a stub vibrator with a classical dipole are connected in parallel via a symmetrical two-wire line, with a shunt switching on of the dipole used to match the input impedance of the antenna with the characteristic impedance of the cable.

The novelty in terms of the device is seen in the fact that for phasing the delay device is made in the form of a lumped broken extension of the conductors of a symmetrical two-wire line, with its direct typical and shunt connection of different vibrators.

The novelty in terms of the device is seen in the fact that the matching balancing device of the receiving excitation element is made in the form of a coaxial cable, and on the length of the coaxial cable, commensurate with 0.25λ _cf ., the outer insulation is covered with an additional conductive braid, realizing the balancing cup.

The novelty in terms of the device is seen in the fact that the matching balancing device of the receiving excitation element is located along the axis of the antenna, in the zone of zero potential, and along the axis of symmetry of the conductors of a symmetrical two-wire line, within the height between the vibrators, with minimization of the antenna dimensions and the effect on electrical characteristics antenna device.

The industrial applicability of the proposed technical solution is seen in the relative ease of manufacture, improved electrical characteristics, the possibility of using in small-scale production and for wide distribution on an industrial basis at a high competitive level. In comparison with the known analogues and the prototype, the proposed antenna compares favorably with increased functionality, technical, operational and economic characteristics.

The proposed universal balanced television antenna is illustrated by drawings, including the results of computer simulation in the MMANA-GAL program.

In FIG. 1 shows a schematic sketch of a rolled television antenna with two delay knees.

In FIG. 2 shows a computer model of a rolled television antenna with one delay leg.

In FIG. 3 shows the radiation patterns with KU at fixed frequencies.

In FIG. 4 shows a graph of changes in SWR in the operating frequency range.

The roll television antenna contains a receiving excitation element with excitation points (a, b), made mainly of conductive adhesive tape combined in the form of a loop-vibrator 1 with a dipole-vibrator 4 connected in parallel, with vibrator lengths commensurate with 0.5λ _cf , by connecting symmetrical two-wire line 2, with shunt connection through delay device 3 to points (c, d). The excitation receiving element is located on the surface of a substrate made of a thin dielectric transparent rolled material. Along the axis of symmetry (o, ol) of the antenna in the zone of zero potential there is a matching balancing device in the form of a coaxial power cable 6, parallel to the two-wire line 2. The cable is connected by a central core and a braid to the excitation points (a, b), and the insulated surface from the position of the excitation points (a, b), covered with an additional braid 5, comparable in length to 0.25? i _cp ., and connected by its end to the braid of the power cable and the central point (ol) of the dipole 4.

Works roll television antenna, depicted in a schematic sketch (Fig. 1) on a computer model (Fig. 2) as follows.

The maximum level of signal amplitudes from the side of the arrival of radio waves, in the proposed antenna in the form of a loop-vibrator 1 with a dipole connected in parallel 4, located in the same plane, will be obtained when their location plane is parallel to the front of the arrival of radio waves, that is, perpendicular to the direction to the television center . This is provided that, in order to ensure the maximum level of the amplitudes of the received signals at the excitation points (a, b), the induced electromotive force (EMF) in the conductors from the received signals from the loop vibrator 1 and the dipole 4 will come in the same phase, that is, summed up. In addition to this, to reduce the SWR, the maximum transmission of the received signals to the receiver, it is required that the antenna impedance at the points (a, b) of its connection to the coaxial power cable 6 correspond to the characteristic impedance of the coaxial cable used. It is well known that the resistance of the loop vibrator is about 240-280 Ohm, and the resistance of the dipole - the split vibrator is 72-73 Ohm, then their parallel connection will reduce the total resistance and will not ensure coordination with the 75 Ohm television coaxial cable. Therefore, in order to match the antenna resistance at points (a, b) when connected to a coaxial power cable 6, an increase in the dipole 4 connected in parallel via a symmetrical two-wire line 2, the connection resistance is increased by shunting at points (c, d). In addition, such a connection, with the distance of the switching points from the center, relative to the classical inclusion of a split vibrator, introduces a phase shift. In turn, to ensure the addition of signals from the loop vibrator 1 and dipole 4 in phase, at points (a, b), taking into account the phase shift, when the dipole is shunted at points (c, d) and the length of the symmetrical two-wire line 2 , for the required total phase shift, a delay device 3 is included in the two-wire line. Balancing at the transition from the excitation points (a, b) to the coaxial power cable 6 is carried out using a balancing device, in the form of a balancing cup, using cable insulation wrapped with an additional braid 5 , comparable in length to 0.25λ _cf. . For comparison, in this technical solution, undoubtedly, an in-phase grating is implemented, combined from vibrators of various types, which should entail an increased KU, which largely depends on the absorption surface. In turn, in order to reduce the size of the antenna, if it is necessary to minimize the spacing of the vibrators to the length of the balancing device, the absorption regions of the used vibrators overlap, which leads to a limited increase in the gain, but the skew is reduced, which advantageously expands the operating frequency range, as can be seen in the KU table (Fig. 3) and on the SWR change graph (Fig. 4).

In a universal balanced television antenna oriented towards the television center, an EMF is induced in the loop-vibrator 1 and dipole 4 and, with shunt switching, to adjust the resistances, to the points (c, d) of the dipole 4, through the delay device 3, using a symmetrical two-wire line 2, when connected in parallel at points (a, b), the currents are summed in phase. An unbalanced line of the coaxial power cable 6 is connected to the balanced output of the antenna matched in terms of resistance to the wave impedance of the coaxial cable at points (a, b). ,25λ _sr. . The quality of the universal balanced television antenna is clearly illustrated by the graphs of changes in SWR and KU (Fig. 3 and 4).

From the analysis of the above graphs it follows that the proposed antenna is operable in the entire television range of radio wavelengths. Practically with a constant radiation pattern in the entire frequency band allocated for digital television, the SWR changes smoothly and is less than 1.75, and with increasing frequencies and less than 1.25 with an increase in the gain, which is necessary when using antennas in a wide frequency range and provides autonomous operation without an amplifier. In turn, connecting a television receiver through an external antenna amplifier included in the power cable circuit in the complex will improve performance to the level of multi-element antennas of complex designs and significantly increased cost. The arguments on the operation of the antenna according to the proposed technical solution are confirmed by the results of computer simulation and the work of the prototype. The SWR curve in Fig. 4 clearly demonstrates the improved matching in the extended operating bandwidth while maintaining the directivity of the diagrams in FIG. 3, indicates a complete solution of the task and favorably distinguishes the proposed technical solution from analogues. The ease of fabrication of the device from available materials and the versatility of its application open up prospects for its wide use.

Claims (1)

A roll television antenna, including a conductive excitation receiving element fixed or made on the surface of a substrate made of a thin dielectric material, the excitation points of which are connected through a matching device to connect the receiving equipment, characterized in that the excitation receiving element is made of mainly conductive adhesive tape combined , in the form of a loop-vibrator with a parallel position and connected by means of a symmetrical two-wire line, with shunt connection through a dipole-vibrator delay device, with vibrator lengths commensurate with 0.5λ _cf ., moreover, the dielectric substrate is made of a transparent roll material, on which along axis of symmetry of the antenna in the zone of zero potential there is a matching balancing device in the form of a coaxial power cable parallel to a two-wire line, which is connected by a central core and braid to the excitation points, and an insulated surface the spine of which, starting from the position of the excitation points, is covered with an additional braid, comparable in length to 0.25λ _cf. and connected by its end to the braid of the power cable and the central point of the dipole.

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