RU225816U1 - MULTI-BAND LOCOMOTIVE ANTENNA FOR OPERATION WITH RADIO EQUIPMENT SUPPORTING MIMO TECHNOLOGY - Google Patents

Abstract

The utility model relates to multi-band locomotive antennas for working with radio equipment that supports MIMO technology. The technical result is to improve the performance characteristics of a multi-band locomotive antenna. The antenna contains two emitters mounted on a common base (1), and each emitter contains a support post (3) mounted on the base (1), a dielectric insert (4) installed on the support post (3), a sleeve-type vibrator (5 ), mounted on a dielectric insert (4), fixed to a supporting post (3) and closed to it, a power bus (6) connected to the vibrator (5) at two symmetrical points located in the lower part of the vibrator (5), a dielectric substrate (7) under the power bus (6), a coaxial connector (8) connected to the power bus (6), and each vibrator (5) has vertical slots made on its outer surface and located at an equal distance from each other, and emitters located on a common base (1) are spaced apart from each other.

Description

Field of technology to which the utility model relates

The utility model relates to multi-band locomotive antennas and is intended for use in conjunction with radio equipment that supports MIMO (Multiple Input Multiple Output) technology as part of mobile radio communication systems in the frequency band 450-3400 MHz, as well as to ensure operation with GNSS standards GLONASS and BeiDou ).

State of the art

Antennas supporting MIMO technology, a method of spatial signal encoding that allows increasing channel capacity, in which data is transmitted using several emitters and received by several emitters, are well known in the art.

A multiport multi-band automotive antenna is known, including several emitters or antennas (see patent US 10263345 B2, class H01Q 21/28, H01Q 1/42, published 04/16/2019). The antenna comprises two or more LTE multiple-input multiple-output (MIMO) emitters, at least one emitter operating on one or more Internet frequencies, at least one emitter operating on one or more satellite navigation frequencies, a base node, and radio dome connected to the base node. In this case, these emitters are located on one base under one radio dome at a distance from each other. This invention solves the problem of integrating several emitters of a multi-band automotive antenna in one device by placing them on the same base under the same radio dome. The antenna is installed on the roof of the car.

A multifunctional automotive antenna with support for LTE MIMO is known (see patent US 9083414 B2, class H01Q 1/32, H01Q 21/00, published 07/14/2015). The antenna includes a primary multiple-input multiple-output (MIMO) antenna component having a plurality of antennas; a secondary MIMO antenna component having a plurality of antennas; and a global navigation satellite system GNSS antenna component, wherein the GNSS antenna component is located between the primary MIMO antenna component and the secondary MIMO antenna component and is proximal to the secondary MIMO antenna component.

The disadvantage of the above antennas is the inability to operate on locomotives as part of mobile radio communication systems in the frequency band 450-3400 MHz.

The closest analogue is a multi-band locomotive antenna containing a base covered by a radio-transparent casing, a supporting post, a dielectric insert located inside the casing, a sleeve-type vibrator closed to the post at the upper end, and a power bus, as well as a coaxial connector mounted on the outside of the base, a supporting post is made in the form of a disk with a central pin and is fixed to the base, and the dielectric insert on which the vibrator is mounted is equipped with a central hole and is put on the stand pin. Inside the casing at the base of the antenna there is a GNSS module equipped with a cable for connecting to navigation equipment, routed through the base of the antenna and soldered to an additional coaxial connector (see patent RU 126198, class H01Q 9/00, published 03/20/2013).

The disadvantage of this multi-band locomotive antenna is the inability to work with radios that support MIMO technology.

The technical problem is to ensure the ability of a multi-band locomotive antenna to work with radio equipment that has two antenna connectors and supports MIMO technology, instead of two antennas installed with spatial separation on moving objects.

Disclosure of the essence of the utility model

The technical problem solved by this utility model is to create a multi-band locomotive antenna that ensures the operation of radios that support MIMO technology.

The technical result achieved by this utility model is to improve the performance characteristics of a multi-band locomotive antenna by providing the ability to transmit data in an extended operating frequency band for radios that have at least two antenna connectors and support MIMO technology.

The above technical result is ensured due to the fact that the multi-band locomotive antenna contains an emitter mounted on a base, wherein the emitter contains a supporting post mounted on the base, a dielectric insert mounted on the post, a sleeve-type vibrator mounted on a dielectric insert mounted on the post and closed to it, a power bus connected to the vibrator at two symmetrical points located in the lower part of the vibrator, a dielectric substrate under the power bus, a coaxial connector connected to the power bus, while the vibrator has vertical slots made on its outer surface and located on equal distance from each other, the antenna additionally contains a second emitter, made similar to the first emitter, while the emitters are spaced apart from each other on the specified base.

Improving antenna performance is achieved by changing the antenna design.

The operating frequency band of the antenna can be 450-3400 MHz.

It is advisable to select the distance between the emitters in such a way that a signal attenuation between the emitters of at least 10 dB is ensured throughout the entire operating frequency band with the minimum possible dimensions of the base and height of the antenna in conditions of limited dimensions of the rolling stock.

It is optimal to make each vibrator from an aluminum or brass alloy with a number of vertical slots equal to four, and a depth of vertical slots equal to 60-80% of the vibrator wall thickness.

It is preferable to make each vibrator with an internal cavity from the base side, wherein the vibrator is closed to a stand by its upper surface or through a jumper in the internal cavity of the vibrator, depending on the operating frequency band of the antenna, while the diameter of the internal cavity, the ratio of the heights of the upper and lower parts of the internal cavity formed jumper, the thickness of the jumper corresponds to the operating frequency band of the antenna.

It is advisable to arrange the emitters on a common base symmetrically relative to the longitudinal and transverse axes of the antenna, and the same orientation of the vertical slots of the vibrators of the emitters in space.

It is advisable to make the power bus of each emitter with the possibility of deforming it to tune the antenna in the selected operating frequency band by changing the distance between the power bus and the base.

It is optimal to design the antenna with a radio-transparent casing installed in a groove along the periphery of the base.

It is preferable to make the coaxial connector of each emitter mounted on a cable brought out through the base of the antenna, and with the ability to connect to the body of the moving object.

In one embodiment, the antenna may contain a GNSS navigation module of GLONASS and BeiDou standards, mounted on the base between the first and second emitters, and an additional coaxial connector mounted on a cable brought out through the base of the antenna, and configured to connect the navigation module to navigation equipment.

Brief description of drawings

The utility model will be better understood from the non-limiting description given with reference to FIG. 1 of the attached drawing, which shows a general view of a multi-band locomotive antenna for working with radio equipment that supports MIMO technology.

Implementation of a utility model

The multi-band locomotive antenna is designed for transmitting speech and/or data in the operating frequency band 450-3400 MHz on rolling stock for radio equipment that has at least two antenna connectors and supports MIMO technology, as well as ensuring operation with GNSS standards GLONASS and BeiDou. .

The design of a multi-band locomotive antenna is designed as follows.

In FIG. Figure 1 shows a general view of a multi-band locomotive antenna for working with radio equipment that supports MIMO technology. The antenna structurally consists of a base (1), a radio-transparent casing (2), two emitters mounted on a common base (1). Each antenna emitter is a sleeve-type vibrator (5), mounted on a dielectric insert (4), mounted on a support post (3) and closed to it, while the support post (3) is fixed to the base (1). Each vibrator (5) is connected to a power bus (6). The power bus (6) is connected to the vibrator (5) at two symmetrical points located at the bottom of the vibrator (5). Under the power bus (6) there is a dielectric substrate (7). A coaxial connector (8) is connected to the power bus (6) of each vibrator (5). The power bus (6) of each vibrator (5) is, together with the dielectric substrate (7), a strip line used to adjust the antenna matching. The central cable core of each coaxial connector (8) is soldered to the power bus (6). Coaxial connectors (8), attached to cables brought out through the base (1) of the antenna, are configured to connect to the body of the moving object. In the upper part of the base (1) there is a groove that goes around the vibrators, in which the lower edge of the radio-transparent casing (2) is fixed.

The radiating elements of the antenna are sleeve-type vibrators (5) and vertical supporting posts (3). Each vibrator (5) has vertical slots made on its outer surface and located at an equal distance from each other. The conductive stand (3) of each vibrator (5) is fixed to the conductive base (1) using a threaded connection. The vibrator (5) is fixed to the stand (3) using an internal thread in the upper end of the vibrator (5).

The vibrators are located on a common base (1) with a spatial spacing symmetrically relative to the longitudinal and transverse axes of the antenna, and the vertical slots of the vibrators are oriented in the same way in space.

The distance between the vibrators is selected in such a way as to ensure a signal attenuation between the vibrators of at least 10 dB throughout the entire operating frequency band with the minimum possible dimensions of the base and height of the antenna in conditions of limited size of the rolling stock, and is approximately equal to a quarter of the wavelength of the lower frequency of the operating frequency band. This distance provides the necessary attenuation between the vibrators, which makes it possible to increase the signal-to-noise ratio in the receiving path of radio equipment and, accordingly, the data transfer rate.

Each vibrator receives a useful signal with different phases. The phases of the signals received by the two vibrators can be modified by the built-in MIMO transceivers to obtain the highest signal-to-noise ratio in the radio communication channel.

Each vibrator (5) has four vertical slots located on the outer surface of the vibrator with a 90° offset. Each vertical slot is a rectangular groove. The depth of the vertical slots is 2.0-5.0 mm, which is 60-80% of the vibrator wall thickness. Four vertical slots make it possible to increase the size of the outer surface of the vibrator and create conditions for the formation of a larger number of useful signal modes on it, satisfying the condition of placing an even number of segments of length waves and, among other things, ensure the creation of additional antenna resonance in the lower part of the operating frequency band (below 900 MHz), which increases the efficiency of the antenna. The design of a vibrator with four slots with a depth of 60-80% of the vibrator wall thickness, located on the outer surface of the vibrator at an equal distance from each other, was obtained as a result of numerical modeling and empirically verified by monitoring the SWR level at both antenna inputs at a minimum level. A particularly significant influence is exerted by the correct selection of the number and depth of slots to ensure antenna matching in the lower part of the operating frequency band (up to 900 MHz) and minimizing the depth of radiation pattern unevenness (signal fading) in the upper part of the operating frequency band (over 1700 MHz).

Each vibrator (5) is made with an internal cavity from the side of the base (1), closed to a stand (3) by its upper surface or through a jumper in the internal cavity of the vibrator, depending on the operating frequency band of the antenna, while the diameter of the internal cavity, the ratio of the heights of the upper and the lower parts of the internal cavity formed by the jumper, the thickness of the jumper depends on the operating frequency band of the antenna. The diameter of the internal cavity of the vibrator is selected in the range of 22-35 mm, the ratio of the heights of the upper and lower internal cavities of the vibrator is selected in the range from 0 to 0.5, and the thickness of the internal jumper between the cavities (if any) is selected in the range of 3.0-10 mm . Also, the height of the sleeve-type vibrators (5) can be changed by 2-3 mm depending on the operating frequency band of the antenna.

Each vibrator (5) is made of a conductive material (for example, an aluminum alloy or brass), and the power bus (6) and the dielectric substrate (7) form a strip line and represent a matching transformer that ensures antenna matching in the operating frequency band 450-3400 MHz by changing the distance between the power bus (6) and the base (1). In this case, the power bus (6) has a thickness that allows the antenna to be matched with a 50-ohm coaxial line through mechanical action (for example, the mechanical effect is bending of the power bus), leading to a change in the distance between the power bus (6) and the base (1 ) while maintaining the rigidity of the power bus structure (6). For example, when making a power bus from brass alloy LS-63, its thickness is 0.2-0.35 mm. The thickness of the dielectric substrate, which together with the power bus forms a strip line, is obtained by calculation and confirmed empirically by monitoring the SWR value in the process of matching the impedance of the antenna (emitter) at both inputs and the characteristic impedance of a 50-ohm coaxial line. For example, the thickness of the dielectric substrate under the power bus may be 1.8-2.2 mm.

The procedure for setting up both dipoles (emitters) of a MIMO antenna is the same, and the distance between the power bus and the base may differ for each dipole depending on the results of the setup in order to obtain a minimum SWR at both antenna inputs.

The specific dimensions and relative position of the antenna parts, as well as the choice of feed points, provide the necessary distribution of currents in the operating ranges of the radiating elements to obtain an antenna pattern with a low radiation angle in the vertical plane.

The antenna also contains a navigation module (9) of GNSS standards GLONASS and BeiDou, fixed on the base (1), and an additional coaxial connector (10), fixed on a cable brought out through the base (1) of the antenna and configured to connect the navigation module (9) to navigation equipment. The cable is laid in a groove on the inner surface of the base (1), routed through the base (1) and soldered to an additional coaxial connector (10). The GNSS module (9) is placed in a special recess in the base (1) and secured to the board using sealant. Fixing the GNSS module (9) on the board using sealant provides additional mechanical strength of the structure by damping mechanical vibrations in conditions of increased vibration on moving objects. Thus, the proposed design has increased resistance to vibrations when a moving object moves. Placing the GNSS navigation module (9) on a common base (1) between two vibrators makes it possible to further reduce the influence of the useful radiation of the antenna vibrators on the reception path of the GNSS module due to the interference of signals arriving at the inputs of the vibrators with a certain phase shift created by the transmitter.

The base (1) of the antenna is covered with a protective radio-transparent casing (2), for example made of fiberglass. Inside the casing (2) there are supporting posts (3), dielectric inserts (4), sleeve-type vibrators (5), power buses (6), dielectric substrates (7), and a GNSS module (9). A hole is made in the base (1) of the antenna to remove moisture from the internal volume. A protective radio-transparent casing (2) and a hole for removing moisture ensure the safety of the antenna and the connected transceiver device that supports MIMO technology in case of emergency contact with high voltage circuits and protection from the influence of external weather conditions.

In addition to the external protective casing, the electrical safety of the antenna is ensured by galvanic connection of the central output of each antenna coaxial connector (8) with the vehicle body through direct contact of the central core of the power cable with the vibrator (5) and then through the supporting stand (3) with the base of the antenna (1).

The utility model has been disclosed above with reference to a specific embodiment thereof. There are also other embodiments of the utility model that do not change its essence, as it is disclosed in the present description.

Claims (10)

1. Multi-band locomotive antenna containing a radiator mounted on a base (1), while the emitter contains a supporting post (3) fixed on the base (1), a dielectric insert (4) installed on the post (3), a sleeve-type vibrator ( 5), mounted on a dielectric insert (4), fixed and closed to a stand (3), a power bus (6), connected to the vibrator (5) at two symmetrical points located in the lower part of the vibrator (5), a dielectric substrate (7 ) under the power bus (6), a coaxial connector (8) connected to the power bus (6), while the vibrator (5) has vertical slots made on its outer surface and located at an equal distance from each other, characterized in that contains a second emitter, made similar to the first emitter, while the emitters are spaced apart from each other on the specified base (1). 2. The antenna according to claim 1, characterized in that the operating frequency band of the antenna is 450-3400 MHz. 3. The antenna according to claim 1, characterized in that the distance between the emitters is selected in such a way that a signal attenuation between the emitters of at least 10 dB is ensured throughout the entire operating frequency band with the minimum possible dimensions of the base and height of the antenna in conditions of limited size of the rolling stock. 4. The antenna according to claim 1, characterized in that each vibrator is made of an aluminum or brass alloy, and the number of vertical slots in the vibrator is four, and the depth of the vertical slots is 60-80% of the wall thickness of the vibrator. 5. The antenna according to claim 1, characterized in that each vibrator is made with an internal cavity from the side of the base (1), closed to a stand (3) with its upper surface or through a jumper in the internal cavity of the vibrator, depending on the operating frequency band of the antenna, with In this case, the diameter of the internal cavity, the ratio of the heights of the upper and lower parts of the internal cavity formed by the jumper, and the thickness of the jumper correspond to the operating frequency band of the antenna. 6. The antenna according to claim 1, characterized in that the emitters are located symmetrically relative to the longitudinal and transverse axes of the antenna, and the vertical slots of the vibrators of the emitters are oriented in space in the same way. 7. The antenna according to claim 1, characterized in that the power bus of each emitter is made with the possibility of its deformation to tune the antenna in the selected operating frequency band by changing the distance between the power bus (6) and the base (1). 8. The antenna according to claim 1, characterized in that it contains a radio-transparent casing (2) installed in a groove made along the periphery of the base (1). 9. The antenna according to claim 1, characterized in that the coaxial connector (8) of each emitter is fixed to a cable led out through the base (1) of the antenna and is designed to be connected to the body of the moving object. 10. The antenna according to claim 1, characterized in that it contains a navigation module (9) of GNSS standards GLONASS and BeiDou, fixed on the base (1) between the first and second emitters, and an additional coaxial connector (10) fixed on the cable , output through the base (1) of the antenna, and configured to connect the navigation module (9) to navigation equipment.