WO2001039327A1 - Antennensystem - Google Patents
Antennensystem Download PDFInfo
- Publication number
- WO2001039327A1 WO2001039327A1 PCT/DE2000/004037 DE0004037W WO0139327A1 WO 2001039327 A1 WO2001039327 A1 WO 2001039327A1 DE 0004037 W DE0004037 W DE 0004037W WO 0139327 A1 WO0139327 A1 WO 0139327A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- antenna system
- antenna
- antennas
- control unit
- module
- Prior art date
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q9/00—Electrically-short antennas having dimensions not more than twice the operating wavelength and consisting of conductive active radiating elements
- H01Q9/04—Resonant antennas
- H01Q9/16—Resonant antennas with feed intermediate between the extremities of the antenna, e.g. centre-fed dipole
- H01Q9/28—Conical, cylindrical, cage, strip, gauze, or like elements having an extended radiating surface; Elements comprising two conical surfaces having collinear axes and adjacent apices and fed by two-conductor transmission lines
- H01Q9/285—Planar dipole
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q1/00—Details of, or arrangements associated with, antennas
- H01Q1/27—Adaptation for use in or on movable bodies
- H01Q1/28—Adaptation for use in or on aircraft, missiles, satellites, or balloons
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q1/00—Details of, or arrangements associated with, antennas
- H01Q1/27—Adaptation for use in or on movable bodies
- H01Q1/28—Adaptation for use in or on aircraft, missiles, satellites, or balloons
- H01Q1/285—Aircraft wire antennas
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q1/00—Details of, or arrangements associated with, antennas
- H01Q1/27—Adaptation for use in or on movable bodies
- H01Q1/32—Adaptation for use in or on road or rail vehicles
- H01Q1/325—Adaptation for use in or on road or rail vehicles characterised by the location of the antenna on the vehicle
- H01Q1/3275—Adaptation for use in or on road or rail vehicles characterised by the location of the antenna on the vehicle mounted on a horizontal surface of the vehicle, e.g. on roof, hood, trunk
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q9/00—Electrically-short antennas having dimensions not more than twice the operating wavelength and consisting of conductive active radiating elements
- H01Q9/04—Resonant antennas
- H01Q9/16—Resonant antennas with feed intermediate between the extremities of the antenna, e.g. centre-fed dipole
Definitions
- the invention relates to an antenna system for transmitting and receiving electromagnetic waves, in particular in the short-wave range.
- the invention further relates to a vehicle with such an antenna system, which is suitable for mobile use
- dipole antennas When using antennas in mountainous terrain or when transmitting electromagnetic waves, especially in the shortwave range, the most possible vertical or steep radiation of the energy is required.
- dipole antennas are known as ideal antennas with an as vertical as possible radiation angle (called dipole for short), the length of which corresponds to half the wavelength and which is generally referred to as the lambda half dipole (also called ⁇ / 2 dipole).
- the transmission behavior and vice versa the reception behavior of a lambda half dipole is largely due to a Omnidirectional characteristic and a relatively large vertical radiation angle characterized.
- a disadvantage of the half-wave dipole is that for a particularly broadband use in the shortwave range, for example from 2 to 30 MHz, the antenna length fluctuates between 75 and 5 m.
- the frame antenna is a so-called short-circuit antenna, which in the
- the dipole antenna Compared to the dipole antenna, it has a largely good frequency response in a wide frequency range, whereby the radiation characteristic is limited with regard to a steep radiation angle.As a result of the very high currents of the loop antenna, which are unavoidable during operation of the antenna system, this includes very complex motors and electrical components that are permanently installed of
- an antenna system for frequencies, in particular in the shortwave range comprising two antennas which have one
- Control unit are interconnected and together form a dipole antenna.
- the two antennas are such by means of the control unit electrically connected to each other so that they form a dipole antenna with respect to the directional beam characteristic. This allows a simple construction of the antenna system while utilizing the particularly good steep beam characteristic of a dipole antenna.
- a rod antenna designed as a monopole is expediently provided as the antenna.
- the largely good steep beam characteristic on which the dipole antenna is based is used in the shortwave range.
- rod or monopole antennas due to the low use of rod or monopole antennas
- Input impedance allows a largely simple adaptation of the impedance range, which in turn ensures a particularly simple structure of the control unit.
- the control unit and the two antennas are preferably arranged on a support element.
- the support element is preferably provided for mounting on a vehicle.
- a frame or a roof rack, for example, is used as the support element.
- the antenna system or the antenna system is thus particularly simple to assemble or disassemble.
- the antenna system can be installed on different vehicles without changing the antenna system regardless of the vehicle type by means of the support element and is therefore suitable for universal use on mobile vehicles.
- the two antennas are advantageously connected to the control unit in order to emit a respective associated frequency in such a way that the two associated frequencies are 180 ° out of phase with one another. In other words, the two antennas are excited or fed in opposite phases.
- the interconnection of the two antennas to form a common dipole with such an antiphase relationship of the two frequencies ensures largely good frequency behavior with the greatest possible radiation energy.
- the control unit has a modular structure.
- the control unit expediently comprises at least one adaptation module and one power divider module.
- the matching module serves to match the output of the control unit to the respective input impedance of the two antennas. Each antenna is fed symmetrically by means of the power divider module.
- a signal originating from a transmitter with a predeterminable power is separated by means of the power divider module.
- Such a modular structure of the control unit enables a particularly high degree of availability and independence of the antenna system.
- due to the modular structure of the antenna system it can be converted particularly simply from a dipole arrangement to a simple monopole antenna.
- one of the two antennas is deactivated by the control unit or simply separated from the control unit.
- the adaptation module preferably comprises a measuring unit and a controller. The input impedance associated with the predetermined frequency is determined by means of the measuring unit.
- Control has the effect that, based on the impedance values determined for the two antennas, at least one L / C element and / or the number of so-called network elements required for adaptation, such as L elements, C elements, is activated.
- the tuning or adaptation process preferably runs iteratively for each antenna, ie in an iterative process the measured values determined by the measuring unit are fed to the control system for determining the number of L / C elements required for the adaptation.
- the measurement values and / or the number of L / C elements for both antennas are determined in each iteration cycle, the interdependency of the two antennas being taken into account by their electrical coupling.
- the L / C element or the L / C elements are preferably connected synchronously to ensure that the two antennas are excited in opposite phases.
- the adaptation module expediently has a memory module in which the size and number of L / C elements to be switched, ie corresponding network settings, are stored for different frequencies.
- the deposit is preferably made after a completed adjustment process. For example, for a frequency range from 2 to 30 MHz at intervals of 5 MHz, the associated impedance values and, as a result, the corresponding number, type and / or size of L / C elements are stored. Instead of a current measurement of the input impedance, the corresponding combination and / or number of L / C elements is then automatically activated for a predetermined frequency by means of the control unit.
- a matching module is provided for each antenna. If the two antennas are identical, the associated matching module is constructed identically, as a result of which manufacturing costs are minimized.
- the two adaptation modules are expediently connected to one another via a control cable. After an initialization phase, the two adaptation modules are preferably connected to one another in such a way that one adaptation module works as a master and the other as a slave. The synchronization of the two adaptation modules takes place via the control cable in such a way that the adaptation module working as a master has the required number and values of
- the adaptation module working as a slave receives corresponding synchronized measurement and / or control commands from the master by means of the control cable.
- a transformer is preferably provided as the power divider module to distribute the power of the radiation energy to be output to the two antennas.
- the transformer is particularly robust and simple in construction and separates the signal coming from a transmitter with a total power into two signals, each with half and thus the same power.
- the antenna system is preferably arranged on a vehicle, at least one means being provided which predominantly in the two antennas holds horizontally and diametrically to each other.
- the free ends of the respective antenna are arranged essentially horizontally, the two free ends pointing away from one another at an angle of 180 °.
- the antenna system can comprise at least one antenna (2), which in turn is itself designed as an antenna system with two antennas that are connected to one another via a control unit. This provides an antenna system which is of high quality and has particularly good RF properties.
- the advantages achieved by the invention are, in particular, that the arrangement of two antennas, each designed as a monopole, to form a dipole antenna ensures the particularly good directional beam characteristics which characterize the dipole antenna, while at the same time having a simple structure for the antenna system.
- the largely simple adaptation of the two antennas enables a modular structure of the control unit, as a result of which there is largely good flexibility and mobility of the entire antenna system and interchangeability of individual components.
- 1 shows an antenna system with two antennas connected via a control unit
- FIG. 2 shows an antenna system with a control unit, comprising a matching module and a power divider module,
- FIG. 3 shows an antenna system with a control unit, comprising two adaptation modules and a power divider module, and
- the antenna system 1 comprises two antennas 2, which are connected to one another via a control unit 4.
- the two antennas 2 are connected to one another via a control unit 4.
- Antennas 2 together form a dipole antenna.
- the two antennas 2 are electrically coupled to one another via the control unit 4.
- the two antennas 2 are preferably each designed as a monopoly.
- a monopoly refers to a single rod antenna.
- the two antennas 2 are connected to one another by means of the control unit 4 in such a way that they have the radiation characteristic of a dipole during operation. By interconnecting two monopoles to form a dipole, a beam angle of 70 ° to 90 ° is possible.
- the antennas 2 are connected to the control unit 4 via contacts which are not shown in more detail, for example via simple plug-in or screw connections.
- the control unit 4 is connected by means of a plug unit 6 to a transmitting and / or receiving unit (not shown in more detail).
- the plug unit 6 is designed such that the control unit 4 can be assembled or disassembled particularly easily.
- all components - the antennas 2 and the control unit 4 - are connected to one another in such a way that they can be exchanged as desired or supplemented by further components due to the simple connections.
- the two antennas 2 are fed symmetrically by means of the control unit 4. This means that the two antennas 2 are fed with half the radiation power.
- the frequencies fed to the antennas 2 are preferably 180 ° out of phase with one another. Due to the use of the antenna system 1 for different frequencies in the shortwave range, in particular in a range from 2 to 30 MHz, the control unit 4 also serves to tune the two antennas 2, in particular to adapt them to the input impedance.
- FIG 2 shows the antenna system 1 with an alternative control unit 4, which is modular.
- the control unit 4 comprises an adapter module 8 and a power divider module 10.
- the two modules - adapter module 8 and power divider module 10 - are connected to one another via two control lines 11.
- the power divider module 10 serves to divide the transmission power supplied by an amplifier (not shown), which is fed in half by means of the control lines 11 via the matching module 8 to the respective antenna 2.
- an amplifier power of 400 W each antenna 2 is supplied with 200 W.
- a transformer is preferably provided as the power divider module 10.
- the adaptation module 8 is used to adapt or tune the respective antenna 2.
- the adaptation module 8 has a number of L / C elements (not shown in more detail).
- FIG 3 shows a further alternative embodiment of the control unit 4 with two Anpassmodulen 8 and the "power divider module 10.
- each matching module 8 is connected to an associated antenna. 2
- the two matching modules 8 are connected together via a control cable 16th
- Each of the matching modules 8 is connected via an associated control line 11 is connected to the power divider module 10.
- the respective adaptation module 8 has a measuring unit 12 for determining measured values, in particular for determining input impedances, and a controller 14, which activates a number of L / C elements, in particular the C, required to match the respective input impedance Links, serves.
- the tuning process takes place in an initialization process in which one of the two adaptation modules 8 is defined as master and the other as slave, in such a way that the number of L / C elements required to adapt the two in the master is determined on the basis of the measured values determined by measuring unit 12 Antennas 2 is determined.
- the master supplies the slave by means of the control cable 16 with appropriate measuring and / or setting commands for tuning the associated antenna 2.
- the data exchange is synchronized. In particular, the master ensures that the control commands for
- the described adjustment or The tuning process is an iterative process, with both the measured values and the control commands for controlling the tuning process being determined for each antenna 2 in each iteration cycle
- the antenna system 1 can be reduced to a simple monopole antenna by deactivating one of the two antennas 2, for example by switching it off by means of the controller 14 or by disconnecting it from the matching module 8.
- the respective adaptation module 8 can additionally or alternatively comprise a memory module 18.
- the memory module 18 preferably contains different frequencies in the frequency range from 2 to 30 MHz, e.g. at 5 MHz intervals, the associated impedance values and the resulting required L / C elements (number and size) are stored. Thus, regardless of the current measurement of the input impedance of the respective antenna 2, the tuning of the antenna 2 is automatically made possible for a predetermined frequency.
- FIG. 4 shows a vehicle 18 with an antenna system 1 of the type described above.
- the antenna system 1 is arranged on a support element 20 which is fastened on the roof of the vehicle 18.
- the respective modules are arranged individually or together, for example surrounded by a housing, on the carrier element 20.
- the respective adaptation module 8 for the associated antenna 2 is fastened on the carrier element 20.
- the two antennas 2 are arranged in the center of the two matching modules 8 and are connected to one another via connecting elements (not shown).
- the power divider module 10 is arranged at the base of the two antennas 2.
- the vehicle 18 is therefore not subject to any special requirements that the carrier element 20 with the antenna system 1 can be mounted on different types of vehicles 18 regardless of the vehicle type. Due to its modular structure, the antenna system 1 can easily be arranged on the support element 20. The Individual elements of the antenna system 1 can be exchanged or replaced or supplemented as desired, this can always be done independently of the vehicle 18. A largely good flexibility and mobility of the antenna system 1 is thus ensured.
- the free ends of the two antennas 2 are arranged diametrically to one another.
- the free ends are attached to the associated end of the vehicle 18 in such a way that they are held horizontally and diametrically to one another.
- Such a horizontal arrangement of the two antennas 2 has a positive influence on the radiation characteristic, in particular a radiation angle that is as vertical or steep as possible is achieved, so that when used in the shortwave range, distances of 0 to 300 km and further, depending on the transmission power, the time of day and the radiation direction are possible.
- a rod antenna with a preferred length of approximately 4 m is used as antenna 2, for example for mobile use.
- Rod antennas with a length also have other antennas 2 with a largely good antenna gain and thus with a clear gain in availability with the best possible radiation properties - the best possible steep beam characteristics from 70 ° to 90 ° - and the broadest possible usable frequency range from 2 to 30 MHz of up to 7 m. Due to the particularly simple and compact structure of the
- Antenna system 1 complies with the regulations of the current road traffic regulations, a vehicle with a length of 456 cm and a height of approximately 195 cm preferably being used as the vehicle 18.
Landscapes
- Engineering & Computer Science (AREA)
- Remote Sensing (AREA)
- Aviation & Aerospace Engineering (AREA)
- Physics & Mathematics (AREA)
- Astronomy & Astrophysics (AREA)
- General Physics & Mathematics (AREA)
- Variable-Direction Aerials And Aerial Arrays (AREA)
- Details Of Aerials (AREA)
- Aerials With Secondary Devices (AREA)
Abstract
Description
Claims
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/130,352 US6693602B1 (en) | 1999-11-19 | 2000-11-17 | Antenna system |
SI200030644T SI1232537T1 (en) | 1999-11-19 | 2000-11-17 | Antenna system |
DE50009241T DE50009241D1 (de) | 1999-11-19 | 2000-11-17 | Antennensystem |
EP00988620A EP1232537B1 (de) | 1999-11-19 | 2000-11-17 | Antennensystem |
NO20022354A NO325819B1 (no) | 1999-11-19 | 2002-05-16 | Antennesystem |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE19955950.3 | 1999-11-19 | ||
DE19955950A DE19955950A1 (de) | 1999-11-19 | 1999-11-19 | Antennensystem |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2001039327A1 true WO2001039327A1 (de) | 2001-05-31 |
Family
ID=7929791
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/DE2000/004037 WO2001039327A1 (de) | 1999-11-19 | 2000-11-17 | Antennensystem |
Country Status (5)
Country | Link |
---|---|
US (1) | US6693602B1 (de) |
EP (1) | EP1232537B1 (de) |
DE (2) | DE19955950A1 (de) |
NO (1) | NO325819B1 (de) |
WO (1) | WO2001039327A1 (de) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE10135765A1 (de) * | 2001-07-23 | 2003-02-13 | Bayerische Motoren Werke Ag | Kraftfahrzeug mit einer Antenne |
FR2829622B1 (fr) | 2001-09-11 | 2004-04-09 | Thales Sa | Systeme antennaire a rendement elevee et a forte puissance |
US20090284431A1 (en) * | 2008-05-19 | 2009-11-19 | Bae Systems Information And Electronic Systems Intergration Inc. | Integrated electronics matching circuit at an antenna feed point for establishing wide bandwidth, low vswr operation, and method of design |
DE102014103669A1 (de) * | 2014-03-18 | 2015-09-24 | Thyssenkrupp Ag | Vorrichtung zum Senden- und/oder Empfangen von elektromagnetischen Wellen |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DD120977A1 (de) * | 1975-08-25 | 1976-07-05 | ||
EP0428229A1 (de) * | 1989-11-14 | 1991-05-22 | Hollandse Signaalapparaten B.V. | Abstimmbare Hochfrequenz-Antenne |
EP0809321A1 (de) * | 1996-05-21 | 1997-11-26 | Daimler-Benz Aerospace Aktiengesellschaft | Symmetrierendes Antennenanpassgerät |
GB2316233A (en) * | 1990-12-14 | 1998-02-18 | Dassault Electronique | Wide band radiating device capable of several polarizations |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE120977C (de) | ||||
SE361110B (de) * | 1972-03-29 | 1973-10-15 | Allgon Ab | |
US4201990A (en) * | 1975-04-21 | 1980-05-06 | Hustler, Inc. | Tunable dipole antenna |
US4038662A (en) * | 1975-10-07 | 1977-07-26 | Ball Brothers Research Corporation | Dielectric sheet mounted dipole antenna with reactive loading |
US4319249A (en) * | 1980-01-30 | 1982-03-09 | Westinghouse Electric Corp. | Method and antenna for improved sidelobe performance in dipole arrays |
US4479130A (en) * | 1981-06-05 | 1984-10-23 | Snyder Richard D | Broadband antennae employing coaxial transmission line sections |
NZ235010A (en) * | 1990-08-22 | 1993-12-23 | Deltec New Zealand | Dipole panel antenna with electrically tiltable beam. |
US5517206A (en) * | 1991-07-30 | 1996-05-14 | Ball Corporation | Broad band antenna structure |
US5528252A (en) * | 1994-10-26 | 1996-06-18 | Ntl Technologies Inc. | Dipole television antenna |
-
1999
- 1999-11-19 DE DE19955950A patent/DE19955950A1/de not_active Withdrawn
-
2000
- 2000-11-17 WO PCT/DE2000/004037 patent/WO2001039327A1/de active IP Right Grant
- 2000-11-17 DE DE50009241T patent/DE50009241D1/de not_active Expired - Lifetime
- 2000-11-17 EP EP00988620A patent/EP1232537B1/de not_active Expired - Lifetime
- 2000-11-17 US US10/130,352 patent/US6693602B1/en not_active Expired - Fee Related
-
2002
- 2002-05-16 NO NO20022354A patent/NO325819B1/no not_active IP Right Cessation
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DD120977A1 (de) * | 1975-08-25 | 1976-07-05 | ||
EP0428229A1 (de) * | 1989-11-14 | 1991-05-22 | Hollandse Signaalapparaten B.V. | Abstimmbare Hochfrequenz-Antenne |
GB2316233A (en) * | 1990-12-14 | 1998-02-18 | Dassault Electronique | Wide band radiating device capable of several polarizations |
EP0809321A1 (de) * | 1996-05-21 | 1997-11-26 | Daimler-Benz Aerospace Aktiengesellschaft | Symmetrierendes Antennenanpassgerät |
Also Published As
Publication number | Publication date |
---|---|
DE50009241D1 (de) | 2005-02-17 |
NO20022354L (no) | 2002-05-16 |
EP1232537B1 (de) | 2005-01-12 |
EP1232537A1 (de) | 2002-08-21 |
NO325819B1 (no) | 2008-07-21 |
NO20022354D0 (no) | 2002-05-16 |
DE19955950A1 (de) | 2001-06-13 |
US6693602B1 (en) | 2004-02-17 |
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