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
  • H01Q9/44—Resonant antennas with a plurality of divergent straight elements, e.g. V-dipole, X-antenna; with a plurality of elements having mutually inclined substantially straight portions
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q1/00—Details of, or arrangements associated with, antennas
  • H01Q1/12—Supports; Mounting means
  • H01Q1/22—Supports; Mounting means by structural association with other equipment or articles
  • H01Q1/24—Supports; Mounting means by structural association with other equipment or articles with receiving set
  • H01Q1/241—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM
  • H01Q1/242—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM specially adapted for hand-held use
  • H01Q1/243—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM specially adapted for hand-held use with built-in antennas
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q5/00—Arrangements for simultaneous operation of antennas on two or more different wavebands, e.g. dual-band or multi-band arrangements
  • H01Q5/30—Arrangements for providing operation on different wavebands
  • H01Q5/307—Individual or coupled radiating elements, each element being fed in an unspecified way
  • H01Q5/342—Individual or coupled radiating elements, each element being fed in an unspecified way for different propagation modes
  • H01Q5/35—Individual or coupled radiating elements, each element being fed in an unspecified way for different propagation modes using two or more simultaneously fed points
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q5/00—Arrangements for simultaneous operation of antennas on two or more different wavebands, e.g. dual-band or multi-band arrangements
  • H01Q5/30—Arrangements for providing operation on different wavebands
  • H01Q5/307—Individual or coupled radiating elements, each element being fed in an unspecified way
  • H01Q5/342—Individual or coupled radiating elements, each element being fed in an unspecified way for different propagation modes
  • H01Q5/357—Individual or coupled radiating elements, each element being fed in an unspecified way for different propagation modes using a single feed point
  • H01Q5/364—Creating multiple current paths
  • H01Q5/371—Branching current paths
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q7/00—Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop
• • 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
  • H01Q9/0407—Substantially flat resonant element parallel to ground plane, e.g. patch antenna
  • H01Q9/0421—Substantially flat resonant element parallel to ground plane, e.g. patch antenna with a shorting wall or a shorting pin at one end of the element
• • 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
  • H01Q9/30—Resonant antennas with feed to end of elongated active element, e.g. unipole
  • H01Q9/42—Resonant antennas with feed to end of elongated active element, e.g. unipole with folded element, the folded parts being spaced apart a small fraction of the operating wavelength

Definitions

• the present invention relates generally to antenna devices and more particularly to an antenna device for a portable radio communication device operable in at least a first lower and a second higher frequency band.
• the invention also relates to a portable radio communication device comprising such an antenna device.
• Internal antennas have been used for some time in portable radio communication devices. There are a number of advantages connected with using internal antennas, of which can be mentioned that they are small and light, making them suitable for applications wherein size and weight are of importance, such as in mobile phones.
• the use of internal antennas in a mobile phone puts some constraints on the configuration of the radiating elements of the antenna.
• the space for an internal antenna is limited. These constraints may make it difficult to find a configuration of the antenna that enables the desired use. This is especially true for antennas intended for use with radio signals of relatively low frequencies as the desired physical length of such antennas are large compared to antennas operating with relatively high frequencies .
• One specific application operating in a relatively low frequency band is the FM radio application.
• the FM operating band is defined as frequencies between 88- 108 MHz in most of the world and frequencies between 76-90 MHz in Japan.
• Prior art conventional antenna configurations such as loop antennas or monopole antennas, fitted within the casing of a portable radio communication device will result in unsatisfactory operation in that the antenna either has too bad performance over a sufficiently wide frequency band or sufficient performance over a too narrow frequency band.
• a conventional FM antenna for portable radio communication devices is usually provided in the headset wire connected to the communication device.
• a portable radio communication device is today many times provided with frequency operational coverage for other frequency bands than FM, such as GSM900, GSM1800, Bluetooth, WLAN, WCDMA and GPS.
• a portable radio communication device has limited space and it is thus desirable to, if possible, add multiple functionality to an antenna. The antenna is then to resonate in more than one frequency band. This is hard to accomplish in a small portable radio communication device.
• a mobile phone may for instance be provided with a component area including a circuit board with components, a battery area, with a battery and with a basic communication antenna section, which includes antennas for basic communication for instance for GSM antennas.
• An object of the present invention is to provide a small-sized antenna device that provides improved multiband functionality. Another object is to provide an antenna device that can provide simultaneous multiband functionality.
• the invention is based on the realization that improved multiband functionality can be obtained in an antenna device by providing a first elongated radiating element for operation in a first lower frequency band and having a first and a second opposite end and a second elongated radiating element joined to the first end of the first radiating element.
• the second element stretches away from the first radiating element and is dimensioned for resonating in the second frequency band. In this way the first end of the first radiating element defines a first junction.
• the antenna device further includes a first feeding connection leading to the first junction, a first connection path between the first feeding connection and a first frequency band signal handling unit, a first tuning element connected to the first connection path and being arranged to tune the first radiating element for resonance in the first frequency band, a first signal passing and blocking arrangement arranged to allow signals in the first frequency band to pass through the first connection path and to block signals in the second frequency band from passing through the first connection path, a second connection path provided between the first junction and a second frequency band signal handling unit and a second signal passing and blocking arrangement arranged to allow signals in the second frequency band to pass through the second connection path and to block signals in the first frequency band from passing through the second connection path.
• a first aspect of the present invention there is provided an antenna device as defined in claim 1.
• the invention has a number of advantages.
• the radiating elements of the antenna device that provides multiband operation are very small. Multiband operation is furthermore obtained simultaneously. There is no switching between operations in different bands. This has the advantage of providing a more rapid signal processing as well as energy savings.
• the radiating elements of the antenna device are also simple to produce. These advantages are obtained while considering environmental limitations imposed by the portable radio communication device in which the antenna device is to be placed.
• Fig. 1 is a front view of a portable radio communication device comprising an antenna device according to the invention
• Fig. 2 schematically shows a view from above of the interior of the portable radio communication device
• Fig. 3 schematically shows a perspective view of an antenna device according to a first embodiment of the present invention
• Fig. 4 schematically shows perspective view of the antenna device in the first embodiment being provided above a circuit board with frequency band signal handling units;
• Fig. 5 schematically shows a perspective view of an antenna device according to a second embodiment of the present invention connected to frequency band signal handling units and being provided above a reference plane;
• Fig. 6 schematically shows a perspective view of an antenna device according to a third embodiment of the present invention connected to frequency band signal handling units and being provided above a reference plane;
• Fig. 7 schematically shows a perspective view of an antenna device according to a fourth embodiment of the present invention connected to frequency band signal handling units and being provided above a reference plane.
• Fig. 1 shows a front view of the exterior or casing of a portable radio communication device 2, in the form of a mobile phone.
• a mobile phone is just an example of one type of portable radio communication device.
• Other examples are lap top computers, palm top computers, electronic organizers and electronic gaming machines.
• Fig. 2 schematically shows a view from above of the interior of the portable radio communication device 2 from fig. 1.
• a circuit board section 4 There is here a circuit board section 4, a battery section 6 and a basic communication antenna section. These sections are provided side by side laterally in relation to each other.
• the circuit board section 4 provides a component area, where components such as radio circuits or frequency band signal handling units, i.e.
• the basic communication antenna section includes antennas for basic communication like various types of cellular communication and may thus for instance be GSM antennas.
• the basic communication antenna section 8 is connected with the circuit board 4 via a flex film 10 holding conductors being placed over the battery 6.
• the radiating elements of an antenna device of the invention are then connected to such frequency band signal handling units as well as to a ground plane.
• This ground plane is normally provided as a part of the circuit board.
• the radiating elements can be seen as forming an antenna 11.
• the radiating elements of the antenna 11 shown in fig. 2 are here the radiating elements provided according to a first embodiment of the invention. As can be seen part of the antenna 11 stretches over the battery section 6 and part over the circuit board section 4.
• the problem with the various sections mentioned above is that for antennas operating at high frequencies, such as Bluetooth, WCDMA_Rx, and GPS, the battery section 6 provides high losses, while the circuit board section 4 provides low losses.
• the battery section has a limited influence on the performance.
• the circuit board section 4 may have a high level of electromagnetic interference at low frequencies but not at high frequencies.
• the present invention is directed towards providing a multiband antenna device operating in at least a first lower and a second higher frequency band that considers such limitations imposed by an environment, such as the environment in a portable radio communication device with various sections. These bands may with advantage be separated from each other by more than 1 GHz.
• the first radiating element has a first end 18 as well as a second opposite end 20.
• the first radiating element 16 may typically have the first end 18 provided at or close to a first corner of the circuit board where a first and a second circuit board side meet.
• the first radiating element then stretches along the first side of the board 4 in the direction towards this first corner and then continues past this first corner in the same direction away from the circuit board and thus continues along a first side of the battery 6, which first side of the battery has the same orientation as the first side of the circuit board 4. This part of the first radiating element is here straight.
• the first radiating element 16 makes a ninety degree turn and runs to the second end 20.
• Fig. 5 shows a perspective view of an antenna device according to a second embodiment of the present invention being provided above a reference plane.
• This reference plane represents a combination of the circuit board and battery shown in fig. 4.
• a third elongated radiating element 38 This stretches away from the first radiating element and here inwards towards the circuit board.
• an additional radiating element 40 that also stretches away from the first radiating element. This element may stretch in parallel with the third element.
• the third radiating element is here provided in a plane parallel with and distanced from or spaced above the ground plane as is the further radiating element. They may furthermore be provided in the same plane as may the first and the second radiating elements.
• the third signal passing and blocking arrangement is configured to always allow signals in the third frequency band and in this embodiment also in the additional frequency band to pass through the third connection path and to always block signals in the first frequency band from passing through the third connection path P3.
• the third signal passing and blocking arrangement includes a third filter 42 connected between the second junction 20 and the diplexer 44.
• this third filter may be a high pass filter.
• this third filter is provided in the form of a capacitor 42 connected between the radiating elements 38 and 40 and the diplexer 44, which capacitor in these embodiments has, only as an example, a value of 1 pF.
• a high pass filter may be realized in other ways.
• the third filter is not limited to a high pass filter but may also be a band pass filter with the pass band set to cover the third frequency band and any other frequency bands of signals that are to pass the second connection path.
• the second, third and additional radiating elements here function as ILA antennas that each resonate and preferably with fundamental resonance.
• This third embodiment looks quite similar to the second embodiment. However here there is no second feeding connection. Instead there is a grounding connection GC, which connects the second junction 20 with ground via an inductor 50, which has an exemplifying value of 10 nH.
• the third path P3 is connected to the grounding connector, however without any third filter.
• the inductor 50 acts as a matching element for the third and additional radiating elements but as a short-circuit to ground for the first frequency band. Since the first radiating element is grounded for the first frequency band, there is no need for the third filter.
• the only difference at the first junction compared with the second embodiment is the first connection path and the first tuning element.
• the second, third and additional radiating elements are acting as ILA antennas as before.
• the grounding connection GC provides ground for the first radiating element. It also provides feed for the third and additional radiating element. Therefore the first radiating element 16 acts as a half loop antenna, which can be seen as half a magnetic dipole antenna.
• the first tuning element Tl ' can be provided as a capacitance connected to ground instead of an inductor connected to ground.
• the first tuning element Tl' is here as an example a capacitance of 30 pF.
• the first tuning element Tl' when provided in this way will also provide a path to ground for operations in the second frequency band.
• a further filter 49 is provided between the first tuning element Tl ' and the first radiating element 16.
• the first tuning element Tl' and the first filter 24 share the same connection to the first radiating element 16.
• the further filter may be considered as a part of the first signal passing and blocking arrangement. Because of this the further filter 49 is provided in the first path Pl and here between the first radiating element 16 and the first filter 24.
• the first tuning element Tl' is then connected between ground and the junction between the first filter 24 and the further filter 49.
• the further filter may here be a low pass filter in the form of an inductor having an exemplifying value of 20 nH.
• Fig. 7 shows a perspective view of an antenna device according to a fourth embodiment of the present invention being provided above a reference plane.
• This embodiment has the same radiating elements as in the third embodiment.
• the second and third connection paths are provided in the same way as in the third embodiment.
• the first connection path is in many ways similar to the connection path of the third embodiment. The only difference between these two paths is that the further filter is omitted. This is done since it is no longer needed.
• the first connection path is joined with the first junction 18 via the first feeding connection FCl and the third connection path is joined to the second junction 20 via the second feeding connection FC2 like in the second embodiment.
• the second connection path is here joined with the first junction 18 via a further feeding connection FC3 and the second junction 20 connected to ground via a grounding connection GC.
• Each end of the first radiating element is thus provided with two connections, where three of these are feeding connections and one is a grounding connection.
• the first radiating element is here a half-loop element.
• the second, third and additional radiating elements are IFA (Inverted F Antenna) elements.
• the first feeding connection FCl is a ground connection for the second radiating element, while the grounding connection GC acts as a grounding connection for both the first radiating element as well as the third and additional radiating elements.
• the reason for the first feeding connection FCl acting as a ground connection is that the first tuning element Tl ' acts as a short-circuit to ground in the second frequency band for the second radiating element.
• the fourth embodiment can also be varied in the same way as the previous embodiments regarding which feeding connections are to be branched and which are to receive further or additional radiating elements. It is actually possible that both ends of the first radiating element provides additional functionality for two different frequency bands with one or two radiating elements.
• the first radiating element can be combined with either ILA or IFA elements at one or both ends. This means that it is also possible with the radiating elements connected to one end of the first radiating element to act as IFA, while the other radiating elements connected to the other end of the first radiating element act as ILA.
• the feeding and grounding connections may typically be provided as conductors which can lead from the plane of the circuit board to the plane in which the radiating elements are provided.
• connection paths may be provided on the circuit board
• the radiating elements and feeding and grounding connections can also be seen as providing an antenna.
• This antenna is small in size while being adapted in shape to the environmental limitations imposed by a portable radio communication device.
• the second tuning element can be provided in all of the second paths.
• the different bands used may furthermore be varied.
• the second frequency band may thus be any frequency band in the group of WCMA_Rx, GPS or Bluetooth. This is also the case for the third, further and additional frequency bands.
• the first band may be a different band than FM, such as for instance a DVBH television band.
• the dimensioning of the circuit board section and battery section that was described earlier can of course also be varied.
• the circuit board and battery may have any shape this is desired for adapting to the design of the portable radio communication device.
• the placing of the first radiating element is not critical. However space is saved if it is provided closer to the battery section than the circuit board section. However it is advantageous if the other radiating elements are as much as possible spaced from the battery section.
• the different parts of the radiating elements were earlier being described as being straight or the whole elements as being straight. This is not necessary. They may have any desirable shape, such as curved or meandering.
• the signal handling units were here described as separate units. It should be realized that two or more of them may be combined into the same physical entity, such as in the same component. These signal handling units were here also described as excluded from the antenna device. It should be realized that they may as an alternative also be included in the antenna device. Preferred embodiments of an antenna device according to the invention have been described. However, it will be appreciated that these can be varied within the scope of the appended claims. Therefore the present invention is only to be limited by the following claims.

Landscapes

• Engineering & Computer Science (AREA)
• Computer Networks & Wireless Communication (AREA)
• Variable-Direction Aerials And Aerial Arrays (AREA)
• Support Of Aerials (AREA)
• Waveguide Aerials (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=41202456

Family Applications (1)

Country Status (2)

Families Citing this family (5)

Citations (8)

Family Cites Families (2)

• 2009
  • 2009-05-11 EP EP09159923A patent/EP2251930A1/de not_active Withdrawn
• 2010
  • 2010-05-04 WO PCT/EP2010/056050 patent/WO2010130603A1/en active Application Filing

Patent Citations (8)

Also Published As

Similar Documents

Legal Events