Tuneable antenna for a wireless communication device

Abstract

The present invention relates to a tuneable antenna for a wireless communication device comprising at least one antenna element and at least one adaption element. The adaption element has an electric and/or magnetic susceptible material and is moveable relative to the antenna element. The position of the adaption element relative to the antenna element is adjustable by at least one actuator as a function of at least one of the antenna characteristics.

Claims

1. A tuneable antenna for a wireless communication device, comprising: at least one antenna element; at least one adaption element, wherein the adaption element has an electric and/or magnetic susceptible material and is movable relative to the antenna element, wherein the position of the adaption element relative to the antenna element is adjustable by at least one actuator as a function of at least one antenna characteristic associated with the at least one antenna element; control means for controlling the at least one actuator for adjusting the position of the adaption element relative to the antenna element and/or for determining the at least one of the antenna characteristic; and at least one tuneable matching circuit for adjusting the impedance of the antenna, and wherein the tuneable matching circuit interacts with the control means for adjusting the impedance of the antenna and the control means are adapted for adjusting the position of the adaption element relative to the antenna element as a function of the at least one antenna characteristic.

2. The antenna according to claim 1, wherein the at least one antenna characteristic is the radiation pattern of the antenna.

3. The antenna according to claim 1, wherein the at least one antenna characteristic is at least one resonant frequency of the antenna.

4. The antenna according to claim 1, wherein the function of the antenna characteristic is dependent on the conditions of transmitted and/or received antenna power of the antenna.

5. The antenna according to claim 1, wherein the at least one antenna characteristic is electrically and/or magnetically influenceable from the extent of overlapping of the body of the adaption element and the body of the antenna element.

6. The antenna according to claim 1, wherein the antenna further comprises a magnet, wherein the magnet and the adaption element are moveable relative to each other.

7. The antenna according to claim 1, wherein the adaption element and/or the electric susceptible material of the adaption element is shaped to adjust the at least one antenna characteristic.

8. The antenna according to claim 1, wherein the electric susceptible material of the adaption element has a very high relative permittivity or dielectric constant.

9. The antenna according to claim 8, wherein the electric susceptible material is one of Aluminum oxide, Titanium oxide, Strontium Titanate, low-loss ferrites or a combination thereof.

10. The antenna according to 1, wherein the magnetic susceptible material of the adaption element has a high relative permeability or magnet constant.

11. The antenna according to 10, wherein the magnetic susceptible material is a low-loss ferrite.

12. The antenna according to claim 1, wherein the adaption element and/or the magnetic susceptible material of the adaption element is magnetically influenceable from the extent of overlapping of the body of the adaption element and the body of the magnet.

13. The antenna according to claim 1, wherein the adaption element is rotatable and/or pivotable relative to the antenna element.

14. The antenna according to claim 1, wherein the adaption element is mounted on the actuator.

15. The antenna according to claim 1, wherein the actuator is an electric motor.

16. The antenna according to claim 15, wherein the actuator is a motor causing vibrational movement.

17. The antenna according to claim 1, wherein the antenna comprises: a first antenna element operable in a first frequency band; and a second antenna element operable in a second frequency band, wherein the resonant frequency of the first frequency band is separately adjustable from the resonant frequency at the second frequency band by at least one actuator.

18. A tuneable antenna for a wireless communication device, comprising: at least one antenna element; at least one adaption element, wherein the adaption element has an electric and/or magnetic susceptible material and is movable relative to the antenna element, wherein the position of the adaption element relative to the antenna element is adjustable by at least one actuator as a function of at least one antenna characteristic associated with the at least one antenna element; a controller for controlling the at least one actuator for adjusting the position of the adaption element relative to the antenna element and/or for determining the at least one antenna characteristic; and at least one tuneable matching circuit for adjusting the impedance of the antenna, and wherein the tuneable matching circuit interacts with the controller for adjusting the impedance of the antenna and the controller are adapted for adjusting the position of the adaption element relative to the antenna element as a function of the at least one antenna characteristic.

19. The antenna according to claim 18, wherein the controller is implemented as an open-loop controller or a closed-loop controller.

20. The antenna according to claim 18, wherein the at least one antenna characteristic is at least one resonant frequency of the antenna.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows a principal exemplary embodiment of an antenna according to the present invention;

(2) FIG. 2 shows a principal exemplary embodiment of a further antenna according to the present invention;

(3) FIG. 3 shows a principal exemplary embodiment of a further antenna according to the present invention;

(4) FIG. 4 shows a principal exemplary embodiment of a further antenna according to the present invention;

(5) FIG. 5A shows in a detailed view a principal exemplary embodiment of an arrangement of an electric motor and an adaption element of an antenna according to the present invention;

(6) FIG. 5B shows a sectional view along axis AA according to FIG. 5A;

(7) FIG. 6 shows in a detailed view a principal exemplary embodiment of an overlapping of an adaption element and an antenna element of an antenna according to the present invention;

(8) FIG. 7 shows a principal exemplary embodiment of a further antenna according to the present invention; and

(9) FIG. 8 shows in a detailed view a principal exemplary embodiment of an overlapping of an adaption element and a magnet of an antenna according to the present invention.

DETAILED DESCRIPTION

(10) FIG. 1 shows a principal exemplary embodiment of an antenna 1 according to the present invention. The antenna 1 as an electrical device converts electrical power into radio waves and vice versa.

(11) The antenna 1 is arranged on a circuit board 10 and consists of an arrangement of metallic conductors as antenna elements 11 and 12, which are electrically connected from a feedpoint 19 via a connection 60 to other electrical components, in the present case especially control means 40 for controlling and/or tuning the antenna characteristic. With that the antenna 1 comprises an antenna volume associated with the antenna 1 for sending and/or receiving electromagnetic signals. The antenna 1 and/or the antenna elements 11 and 12 are suitable for transmitting and/or receiving electromagnetic signals in a certain frequency or frequency band, especially frequencies according to GSM, UMTS and/or LTE. The antenna 1 may also include additional elements or surfaces, such as parasitic elements (not shown in FIG. 1).

(12) The antenna 1 further comprises an electric motor 30, especially a vibra, which is located or arranged close to the antenna 1, especially within the antenna volume. The vibra 30 is at hand used as an actuator on which an adaption element 20 is mounted. The adaption element 20 consists of or comprises an electric susceptible material, presently a dielectric material, which has a high-dielectric constant with a minimal loss. The dielectric material or dielectric of the adaption element 20 acts like an electrical insulator and effects the electric field of the antenna 1 when placed therein. The dielectric is a material with a high polarizability, which is expressed by a constant or number called the relative permittivity also known as dielectric constant . The relative permittivity is frequency-dependent. The dielectric material of the adaption element 20 at hand is preferably Aluminum oxide, Titanium oxide, and/or Strontium titanate or low-loss ferrites, such as YIG film (YIG: Yttrium Iron Garnet).

(13) The electric motor respectively vibra 30 serving as actuator of the adaption element 20 is electrically connected to the control means 40 via connections 50 and is at hand horizontally arranged on the circuit board 10. The rotational axis of the electric motor 30 is orientated vertical to the area or surface of the circuit board 10. A rotation about the rotational axis of the electric motor 30 is designed to adjust the position of the adaption element 20 relative to the antenna elements 11 and 12. The area or the longitudinal axis of the adaption element 20 is also orientated vertical to the area of the circuit board 10. The adaption element 20 is clockwise and/or counter-clockwise rotatable around the rotational axis of the electric motor 30, especially in a range between a first angle and a second angle relative to the rotational axis of the actuator or in a range of an angularity relative to the rotational axis of the actuator. The range between the first and second angle or the range of angularity is preferably between 0 to 360 or between 0 to 180. The adaption element 20 at hand is non-rotationally-symmetric arranged on the electric motor 30 with respect to the rotational axis of the electric motor 30.

(14) In a further embodiment of the present invention (not shown) the adaption element 20 respectively dielectric material of the adaption element 20 is rotationally symmetric with respect to the rotational axis of the electric motor 30. In the latter case the dielectric material of the adaption element 20 has to have a non-rotationally symmetric shape with respect to the rotational axis of the electric motor 30. The adaption element 20 and/or the electric motor 30 can be arranged in such a way that the adaption element 20 respectively the dielectric material of the adaption element 20 is moved or rotated on a level with a distance to the antenna elements 11 and 12. This can be between the antenna elements 11 and 12 respectively the body of the antenna elements 11 and 12 below the circuit board 10 (compare for example FIG. 1, FIG. 2, FIG. 3) and/or above the circuit board 10 (compare for example FIG. 4).

(15) The dielectric material of the adaption element 20 has a shape that is designed to adjust a factor of inhomogeneity of the antenna characteristics, for example as a function of the position of the dielectric material of the adaption element 20 relative to the antenna elements 11 and 12. The shape of the dielectric material of the adaption element 20 is preferably a semicircle, a sector and/or of a rectangular form. The factor of inhomogeneity is dependent on a position or angular of the dielectric material of the adaption element 20 relative to the rotational axis of the electric motor 30.

(16) In a further embodiment of the present invention (not shown) it is proposed that the electric motor 30 and the dielectric material of the adaption element 20 are arranged separately from each other, for example especially on the circuit board 10, whereby the dielectric material of the adaption element 20 is movableespecially by the electric motor 30relative to the antenna 1 or the antenna elements 11 and 12.

(17) The electric motor 30 isas mentioned abovedesigned to move or rotate the adaption element 20 respectively the dielectric material of the adaption element 20 relative to the antenna 1 respectively antenna elements 11 and 12. For this the electric motor 30 at hand has a direct-current source which enables the electric motor 30 to rotate or move the dielectric material of the adaption element 20 mounted thereon clockwise or counter-clockwise about the motor's rotational axis in a full revolution or alternatively in a range of angles respectively angular ranges, especially between an angle of 0 to 180. The angle is advantageously monitored and/or controlled by the control means 40, which preferably control the electric motor 30 to adjust the position of the adaption element 20 respectively the dielectric material of the adaption 20 relative to the antenna elements 11 and 12.

(18) The control means 40 advantageously comprise a chip set which has a tuning interface to tune the electric motor 30. The tuning is preferably done by controlling the steering voltage of the electric motor 30 and the angle position of the motor driven actuator or the dielectric material respectively adaption element 20. The characteristic curve of the combination of antenna 1, motor 30 and dielectric material of the adaption element 20 is captured or recorded as at least one of the antenna characteristics, especially to be able to adjust the position of the dielectric material of the adaption element 20 relative to the antenna elements 11 and 12. The values of this characteristic curve are preferably also stored within the chip set 40.

(19) The chip set of the control means 40 further advantageously comprises software for controlling the process of adjusting the position of the dielectric material of the adaption element 20 relative to the antenna elements 11 and 12 as a function of the antenna characteristics. The software contains respectively comprises algorithms for optimizing the characteristic of the antenna 1 or the antenna performance. The control means 40 are preferably be operated as an open-loop controller or a closed-loop controller.

(20) The control means 40 advantageously further interacts with sensor means or detector means (not shown) for determining or measuring at least one of the antenna characteristics. The sensor means can for example be integrated within the chipset of the control means 40 or arranged separately within the wireless communications device, for example on the circuit board 10. The type of sensor can be a passive or an active sensor. The sensor is adapted to determine or measure at least one of the antenna characteristics.

(21) FIG. 2 shows a principal exemplary embodiment of a further antenna 201 according to the present invention. The functions of the elements and/or parts of the antenna 201 according to FIG. 2 are similar or correspondent to the one of the antenna 1 according to FIG. 1.

(22) The antenna 201 comprises a first antenna element 211 and a second antenna element 212. The first antenna element 211 is designed to operate in a first frequency band, for example a high frequency band or a low frequency band. The second antenna element 212 is designed to operate in second frequency band, for example in a low frequency band or a high frequency band.

(23) The antenna 201 comprises a first electric motor 230 with a first adaption element 220 respectively dielectric material 220 and a second motor 231 with a second adaption element 221 respectively second dielectric material 221. This configuration enables a selective frequency band optimization for the antenna 201. Each of the electric motors 230 and 231 is electrically connected via separate connections 250 and 251 with control means 240. The control means 240 preferably comprise a chip set for the antenna 201 which is designed to control the electric motors 230 and/or 231.

(24) The position or location of the electric motors 230 and 231 is preferably arranged relative to each of the antenna elements 211 and 212 for a selective adaption of the frequency band of the antenna elements 211 and 212. This also advantageously allows a separate frequency band adaption or adjustment of the resonant frequency of each of the two frequency bands. This further advantageously allows a band selective adjusting of the antenna 201. Advantageously it is proposed that the resonance frequency of the Low Band, for example between 700 MHz to 900 MHz, can be adjusted without significantly and adversely affecting the resonance frequency of the High Band, for example between 1800 MHz to 2600 MHz.

(25) In a further embodiment of the present invention (not shown) the antenna 201 comprises two adaption elements 220 and 221 which are driven by one electric motor. Thereby the electric motor is adapted to control or adjust the position of each of the two adaption elements 220 and 221 separate from each other relative to the antenna elements 211 and 212.

(26) In a further embodiment of the present invention (not shown) the antenna 201 comprises two adaption elements 220 and 221. The antenna 201 further comprises a magnet 270 which is arranged close to the adaption element 221. The adaption element 221 has a magnetic susceptible material. The adaption element 220 has a dielectric material. This combination of adaption elements 220, 221 advantageously effects the antenna characteristics of the antenna 201, such as at least one of the resonant frequencies of the antenna element 211, 212.

(27) FIG. 3 shows a principal exemplary embodiment of a further antenna 301 according to the present invention. The functions of the elements and/or parts of the antenna 301 according to FIG. 3 are similar or correspondent to the one of the antenna 1 according to FIG. 1.

(28) The antenna 301 according to FIG. 3 differs from the antenna according to FIG. 1 in that a tuneable matching circuit 370also called TMC 370is provided for the antenna 301. The TMC 370 is connected with the feedpoint 319 of the antenna 301 and with the control means 340 via connection 360.

(29) The TMC 370 for the antenna 301 is advantageously for impedance matching of the antenna impedance. The TMC 370 is preferably designed for optimizing the antenna impedance of the antenna 301 by changing an applied voltage of the TMC 370 of the antenna 301. The antenna 301 or the antenna elements 311 and 312 itself, especially the effective electrical length of the antenna 301, are advantageously not affected by this measure of impedance matching.

(30) The antenna 301 is advantageously operated with the movable adaption element 320 and the electric motor 330 in combination with the TMC 370. This advantageously results in a variety of useable measures for adjusting the characteristic of the antenna 301. In sum a higher tuning effect for the antenna 301 is achieved, especially for tuning the resonance frequency of the antenna elements 311 and 312. Furthermore advantageously a higher or bigger effect of shifting the resonance frequency, for example from one frequency band at for example about 700 MHz to another frequency band at for example about 800 MHz is achieved by the inventive combination of movable adaption element 320 and electric motor 330 in combination with the TMC 370. Advantageously the TMC 370 can be used for fine tuning the resonance frequency of the antenna 301, especially by tuning in a smaller range compared to the effect of an adjustable adaption element 320 adjusted by a motor 330 alone. Advantageously both measures can be used in combination in such a way that the TMC 370 effects the antenna 301 and the adaption element 320 with the motor 330 especially effects the capacitance and with that the effective electrical length of the antenna 301 and consequently the resonance frequency of the antenna 301.

(31) FIG. 4 shows a principal exemplary embodiment of a further antenna 401 according to the present invention. The functions of the elements and/or parts of the antenna 401 according to FIG. 4 are similar or correspondent to the one of the antenna 1 according to FIG. 1.

(32) The antenna 401 according to FIG. 4 is a so called Inverted F-Antenna also referred to as IFA. The antenna 401 can be applied with lots of different antenna technologies, forms, types or concepts like for example a Planar Inverted Antenna also referred to as PIFA, an Inverted F-Antenna (IFA), a Planar Inverted L-antenna also referred to as PILA or an antenna printed on a circuit boardwhich also includes a slot antenna type, a film antenna with plastic carrier, an antenna containing stamped bent parts or a dipole antenna.

(33) FIG. 5A and FIG. 5B show in a detailed view a principal exemplary embodiment of an arrangement of an electric motor 530 and an adaption element 520 respectively the dielectric material of said adaption element 520 of an antenna according to the present invention. The dielectric material of the adaption element 520 is mounted non-symmetrically relative to a rotational axis 535 of the electric motor or vibra 530. This type of mounting effects advantageously a bigger change of the capacitance of the antenna when moving the dielectric material of the adaption element 520 relative to the antenna element of the antenna.

(34) FIG. 6 shows in a detailed view a principal exemplary embodiment of an overlapping of an adaption element 620, 620 and an antenna element 611 of an antenna according to the present invention.

(35) In a first position I of the adaption element 620 there is no overlapping of the body of the adaption element 620 and the body of the antenna element 611. In the first position I the antenna element 611 is operable with a frequency according to the tuning effect of this first position I.

(36) In a second position II of the adaption element 620, in FIG. 6 than referred to as 620, an extent of overlapping of the body of the adaption element 620 and the body of the antenna element 611, in FIG. 6 marked and referred to as an overlapping area 680, is given. In the second position II the antenna element 611 is operable with a frequency according to the tuning effect of this second position II.

(37) The arrow A in FIG. 6 shows the direction of the rotation or moving of the adaption element 620 from the first position I to the second position II.

(38) FIG. 7 shows a principal exemplary embodiment of a further antenna 701 according to the present invention.

(39) The functions of the elements and/or parts of the antenna 701 according to FIG. 7 are similar or correspond to the antenna 1 according to FIG. 1.

(40) The antenna 701 according to FIG. 7 differs from the antenna according to FIG. 1 in that the adaption element 720 has a magnetic susceptible material preferably a low-loss ferrite such as an Yttrium Iron Garnet film (YIG-film). The antenna 701 further comprises a magnet 770, preferably a permanent magnet. The magnet is stationary located close to the antenna 701 or close to at least one of the antenna elements 711, 712.

(41) The adaption element 720 and the magnet, 770 are movable relative to each other, preferably the adaption element 720, in FIG. 7 is movable relative to the magnet 770.

(42) The magnet 770 is advantageously a permanent magnet preferably formed in one piece of magnetic material such as an alloy of iron, cobalt, nickel or ferrites. The magnet 770 applies a magnetic field, preferably a static magnetic field which is advantageously usable in combination with the magnetic susceptible material of the adaption element 720. By moving the magnetic susceptible material 720 in the applied magnetic field from the magnet 770 the magnetic permeability constant .sub.r is changeable in such a way that advantageously the antenna characteristics of the antenna 701 or influenced especially the resonant frequency or transmitted power.

(43) Alternatively or optionally it is possible to arrange the magnetic susceptible material (720) in a stationary manner close to the antenna 701 and to arrange the magnet 770 moveable to the magnetic susceptible material 720.

(44) FIG. 8 shows in a detailed view a principal exemplary embodiment of an overlapping of an adaption element and a magnet of an antenna according to the present invention.

(45) When moving the magnetic susceptible material or adaption element 820 relative to the magnet 870 into a first position I as depicted in FIG. 8 there is no overlapping of the body of the adaption element 820 and the body of the magnet 870. In this position the antenna element 811 is advantageously operable with a frequency according to tuning effect of this first position I.

(46) In a second position II of the adaption element 820, in FIG. 8 than referred to as 820, an extent of overlapping of the body of the adaption element 820 and the body of the magnet 870, in FIG. 8 marked and referred to as an overlapping area 880, is given. In the second position II the antenna element 811 is operable with a frequency according to the tuning effect of this second position.

(47) The arrow A in FIG. 8 shows a direction of the rotation or moving of the adaption element 820 from the first position I to the second position II.

(48) The exemplary embodiments of the invention shown in the figures of the drawing and explained in connection with the description merely serve to explain the invention and are in no way restrictive.

(49) While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive. The invention is not limited to the disclosed embodiments. Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims.

(50) In the claims, the word comprising does not exclude other elements or steps, and the indefinite article a or an does not exclude a plurality. A single processor or other unit may fulfill the functions of several items recited in the claims. Any reference signs in the claims should not be construed as limiting the scope.

LIST OF REFERENCES

(51) 1 antenna 10 circuit board 11 antenna element 12 second antenna element 18 ground point 19 antenna feed point 20 adaption element 30 motor/electric motor/vibra/actuator 40 control means/chip set 50 connections between actuator and control means 60 connection between antenna feed point and control means 201 antenna 210 circuit board 211 antenna element 212 second antenna element 218 ground point 219 feed point 220 adaption element 221 second adaption element 230 motor/electric motor/vibra/actuator 231 second motor/second electric motor/second vibra/second actuator 240 control means/chip set 250 connections between actuator and control means 251 connections between second actuator and control means 260 connection between antenna feed point and control means 301 antenna 310 circuit board 311 antenna element 312 second antenna element 318 ground point 319 feed point 320 adaption element 330 motor/electric motor/vibra/actuator 340 control means/chip set 350 connections between actuator and control means 360 connection between antenna feed point and control means 370 tuneable matching circuit (TMC) 401 antenna 410 circuit board 411 antenna element 412 second antenna element 418 ground point 419 feed point 420 adaption element 430 motor/electric motor/vibra/actuator 440 control means/chip set 450 connections between actuator and control means 460 connection between antenna feed point and control means 470 magnet 480 overlapping area of adaption element and magnet 520 adaption element 530 motor/electric motor/vibra/actuator 611 antenna element 620 adaption element in position I 620 adaption element in position II 630 motor/electric motor/vibra/actuator 680 overlapping area of adaption element and antenna element 701 antenna 710 circuit board 711 antenna element 712 second antenna element 718 ground point 719 feed point 720 adaption element 730 motor/electric motor/vibra/actuator 740 control means/chip set 750 connections between actuator and control means 760 connection between antenna feed point and control means 770 magnet 811 antenna element 820 adaption element in position I 820 adaption element in position II 830 motor/electric motor/vibra/actuator 870 magnet 880 overlapping area of adaption element and magnet A rotation/movement from position I to position II