RU188638U1 - ANTENNA GRID OF TURNICET TYPE KV RANGE - Google Patents

Abstract

The utility model relates to antenna technology. The turnstile antenna array of the HF range contains two flat inter-orthogonal log-periodic antennas whose planes have a 45 ° inclination to the earth's surface. The suspension system of the antenna vibrators and the common distribution line is made by using a suspension system consisting of upper and lower railings, the ends of which are mounted on collapsible masts, the heights of which provide a grating angle of 12 ° to the horizontal plane. The technical result is to simplify the design of the antenna array, increasing mobility and reducing deployment time. 2 hp f-ly, 5 ill.

Description

The utility model relates to antenna technology and can be used as a transceiver broadband phased antenna array of the decameter range with control of the polarization of the radiated field and the location of the maximum of the main lobe of the radiation pattern used in stationary and mobile communication objects.

Known antennas and antenna arrays with controlled polarization of the radiated electromagnetic field (patents RU 128789 U1, No. 2189676 IPC: H01Q 11/10, A.S. USSR No. 248010 MPK: H01Q 9/24).

A common property of these patented solutions is their work in the centimeter, meter, decimeter ranges.

The closest in technical essence and execution is a broadband antenna according to the patent of the Russian Federation No. 62740 for a utility model (IPC: H01Q 11/10), which assumes operation in the KB range with the provision of polarization control of the radiated field.

The antenna described in patent number 62740 contains two log-periodic structures whose planes are mutually orthogonal and inclined at an angle of 45 ° relative to the surface of the earth. Each log-periodic structure is connected to a symmetrical two-wire power line. The vibrators are suspended from the edges of the metal structure in the form of a truncated equilateral pyramid, and the faces and the support are separated by dielectric inserts into segments whose lengths are selected with variable pitch from 0.1 λmin to 0.1 λmax, where λmin and λmax are the limits of the working frequency range. Parallel to the ground, an axis of the pyramid is installed, along which two two-wire power lines from two power amplifiers are fastened in parallel on the front and rear supports.

The patented design can be used in antenna transceiver location devices.

The disadvantages of this antenna are:

- the connection of radio transmitting devices with an unbalanced output to the balanced inputs of the antenna, as indicated in the description, cannot provide an acceptable level of matching in a wide frequency band;

- the design in the form of a metal truss, separated by insulators, is expensive, complicated and cumbersome even for use on stationary objects and does not provide mobility, rapid deployment and transportability of the antenna;

- does not provide electronic control of the location of the main lobe of the radiation pattern.

The claimed utility model is aimed at solving the following tasks:

- ensuring the increase of the level of effective isotropic radiated power, obtained by improving the level of coordination between the asymmetrical output of the radio transmitting device and the balanced input of a log-periodic antenna;

- simplified design, which will reduce deployment time;

- providing control of the main lobe of the radiation pattern for each of the four (linear - horizontal, vertical and elliptical - circular right and left rotations) types of polarization of the electromagnetic field emitted by the antenna array at each frequency of the working range.

The task of increasing the level of coordination between the outputs of radio transmitters and power points of the log-periodic elements from the antenna array is solved by including in the high-frequency path a broadband balancing and matching device (CSS) having its own VSWR of no less than 1.3 in the entire KB range and made on the basis of flat spiral conductors, providing a transition from an unbalanced coaxial cable with a characteristic impedance of 75 Ohms to a balanced 300-ohm output and the presence of a four-wire A 300-ohm feed line connecting the OSS output and antenna power point. The use of the OSS with its own VSWR of not less than 1.3 allows to achieve the VSWR of the antennas and the antenna-feeder path with respect to 75 Ohms not worse than 3 in the range of operating frequencies.

Simplification of the antenna array design, mobility and reduction of deployment time is achieved through the use of a fundamentally new suspension system at the required height of mutually orthogonal log-periodic antennas whose planes have a 45 ° inclination to the earth's surface. The suspension system of each antenna on the masts consists of upper and lower rails. The emitters are attached to the rails with the help of leads. Leer and leashes are made of synthetic and steel ropes, sectioned with insulators through 2.5 m. The system of suspension of antenna array drawers consists of six collapsible sectional masts. The masts are located along the canvases of antennas, taking into account their inclination: the front have a height of 22 m, average 26 m, rear 30 m. The masts are made of steel ropes, sectioned with rigging insulators after 2.5 m.

FIG. 1 and FIG. 2 shows the construction of the turnstile type antenna array; in fig. 3 - electrodynamic model of two orthogonal log-periodic antennas with a distribution line and a 1: 1 scale model deployed on the ground; in fig. 4 - electrical circuit of the high-frequency path: pathogen, two power amplifiers, two devices for balancing and matching, two four-wire feeder lines, two log-periodic structures with a circuit for connecting vibrators to a distribution line; in fig. 5 - results of measurements of the standing-wave ratio of the layout voltage (1: 1 scale) of log-periodic antennas from the turnstile grid.

Two flat log-periodic antennas with vibrators 10, ground loop 6, two four-wire feeder lines 2, distribution line 11 are suspended on six masts 7, 8, 9, the heights of which are 30, 26 and 22 meters, respectively, provide the required inclination of the antenna array to the horizontal planes at 12 °. The top 4 and bottom 5 rails are attached to the masts, the vibrators 10 are connected to the rails using leads 3. Two four-wire symmetrical lines 2, which are connected to the ground balancing and alignment devices 1, fit the power points of the log-periodic antennas.

The RF signals generated in the exciter (modulator) are transmitted via two channels (channel 1, channel 2) to the inputs of radio transmitters, where they are amplified to the required level. Further, signals from unbalanced outputs of radio transmitting devices (RPDU) are transmitted through coaxial 75-ohm cables to the inputs of balancing and matching devices, where the resistance is transformed to 300 Ohms and the transition to symmetric four-wire lines, which in turn are switched to distribution lines of periodic antenna.

The electronic switching of the polarization type of the electromagnetic field emitted by the antenna array is carried out by forming two signals in the exciter (modulator) with a certain ratio of phase shifts between the channels of the exciter Ψ ₁ (channel 1) and Ψ ₂ (channel 2):

- Ψ ₁ -Ψ ₂ = 0 ° - linear vertical polarization;

- Ψ ₁ -Ψ ₂ = 180 ° - linear horizontal polarization;

- Ψ ₁ -Ψ ₂ = 45 ° - elliptic (right rotation) polarization;

- Ψ ₁ -Ψ ₂ = -45 ° - elliptical (left rotation) polarization;

The control of the lobe of the radiation pattern at each frequency of the working range in the vertical plane is achieved by switching the type of polarization — elliptical, vertical, horizontal. For each type of polarization, the maximum of the radiation pattern is located under the following values of the elevation angle (Δ °) depending on the operating frequency of the range - horizontal (15≤Δ ° ≤25), vertical (35≤Δ ° ≤60), elliptical (25≤Δ ° ≤40).

In the horizontal plane, maximum control is achieved by changing the phase shifts.

The implementation of the achievement of the claimed distinctive features is confirmed:

1. computer simulation results in the 4NEC2X software package;

2. the results of field experiments of an antenna array model of 4-25 MHz range, manufactured on a 1: 1 scale and deployed on the ground, within which the working frequency range was checked, as well as a test of the controllability of the DN in two planes with carrying out route tests on various correspondents.

Claims (3)

1. Antenna array of the turnstile type HF range, containing two flat mutually orthogonal log periodic antennas, the planes of which have a 45 ° inclination to the earth's surface, characterized in that the suspension system of antenna vibrators and the common distribution line are made using an antenna suspension system consisting of upper and lower railings, the ends of which are mounted on collapsible masts, the heights of which provide the angle of inclination of the lattice to the horizontal plane of 12 °. 2. Antenna array of the turnstile type HF range according to claim 1, characterized in that the high-frequency paths between the asymmetrical output of the radio transmitting devices and the antenna power point include broadband balancing devices and matching with the own standing wave voltage coefficient of not more than 1.3, ensuring the level coordination of CWSN оп 3 log-periodic antennas and antenna-feeder paths with respect to 75 Ohms. 3. Antenna array of the turnstile type HF range according to claim 1, characterized in that the electronic control of the location of the main lobe of the radiation pattern and the switching of the polarization of the radiated field is achieved by setting different phase shifts generated in the channels of the pathogen - for linear (vertical) ₁ - ₂ = 0 ° (35≤Δ ° ≤60); for linear (horizontal) Ψ ₁ -Ψ ₂ = 180 ° (15≤Δ ° ≤25); for elliptic (right rotation) ₁ -Ψ ₂ = 45 ° (25≤Δ ° ≤40); for elliptical (left rotation) Ψ ₁ -Ψ ₂ = -45 ° (25≤Δ ° ≤40), where Ψ ₁ -Ψ ₂ is the difference between the oscillation phases formed in the two HF outputs of the pathogen (modulator), Δ ° is the angle the location within which the main lobe of the radiation pattern is located with this kind of polarization.

Images