Communications: radio wave antennas – Antennas – With radio cabinet
Reexamination Certificate
1997-12-22
2001-10-16
Wong, Don (Department: 2821)
Communications: radio wave antennas
Antennas
With radio cabinet
C343S7000MS, C343S873000, C343S845000
Reexamination Certificate
active
06304222
ABSTRACT:
FIELD OF THE INVENTION
The invention generally relates to radio communications handsets, and in particular to internal antenna arrangements.
PRIOR ART
Recent advances in mobile communications have been coupled with increasing demand for miniaturisation of mobile communications handsets. A significant limitation on such miniaturisation is the internal antenna size which cannot easily be reduced.
Existing antennas used in radio communications handsets include extendible monopoles, microstrip patch antennas, inverted L and F antennas, and helix antennas.
Half or quarter wavelength monopoles extend a significant length from the handset and have a number of disadvantages including the inconvenience of such a long protuberance which is easily broken and can be hazardous to users eyes for example.
The microstrip patch, while having a low profile, small size and light weight, has low efficiency or a narrow bandwidth.
The inverted L antenna requires a significant physical length (quarter wavelength) for efficient operation, this is generally not possible within a handset so that a shortened L is generally inefficient. This can be improved by using a tuning element in the form of a stub to the ground plane giving the antenna an inverted F configuration, however this still suffers from inefficiency and limited bandwidth in the physical size constraints applicable to a handset.
The helix antenna, while conveniently short, still requires a significant cylindrical volume which may be extended outside the main body of the handset forming a short protuberance. While this facilitates to some extent miniaturisation of the main handset, the protuberance is inconvenient in practical use. The helix also suffers from a narrow bandwidth.
Various meandering antenna arrangements are also known. U.S. Pat. No. 4021810 discloses a 3D array of meander structure conductors above a ground plane which is complex to produce and is susceptible to the vagaries of manufacturing tolerances. WO96/38882 discloses a printed meandering monopole antenna extending from a mobile handset. While the meandering monopole is shorter than a standard monopole, it still represents an inconvenient protuberance outside the handset. WO93/12559 discloses a planar metallic sheet inverted F antenna having dependant elements angled with respect to the planar structure. As such it is delicate and complicated to manufacture.
In addition to the above mentioned antenna size and volume constraints on the miniaturisation of handsets, there is now an increasing need for a handset to be used in different communications systems such as mobile and cordless telephony or mobiles in different countries, which requires the handset to be operable over more than one frequency band. While a single antenna and a multiple band matching circuit may be employed, this can prove overly complex and costly so that in practice each handset may require a separate antenna for each frequency band together with sufficient spacing between adjacent antennas to minimise coupling effects there between.
OBJECT OF THE INVENTION
It is an object of the present invention to facilitate handset miniaturisation by providing improved or alternative internal antenna arrangements for such handsets.
SUMMARY OF THE INVENTION
In accordance with a first aspect of the present invention, there is provided a radio communications handset comprising:
a speaker having an adjacent volume of free space for acoustic enhancement;
and an antenna arrangement which incorporates said volume within the antenna arrangement.
Preferably the antenna arrangement comprises a ground plane and a radiating element, said volume being located between said ground plane and said radiating element. Preferably the radiating element is spaced a non-uniform distance from said ground plane.
Preferably the antenna arrangement comprises
a ground plane;
a meandering radiating element extending in a series of opposing bends from a radio-frequency feed point and spaced a non-uniform distance from said ground plane;
and wherein said volume is located between said ground plane and said radiating element.
The opposing bends may be effected in more than one plane.
Preferably the antenna arrangement further comprises a planar element connected to the free end of said monopole and extending back along and substantially parallel with said monopole.
The introduction of the planar element allows the second harmonic frequency of the antenna arrangement to be varied; effectively introducing a second controllable resonant frequency band within the single antenna structure.
Preferably the handset further comprises:
an extendible external antenna;
radio frequency transceiver means; and
antenna switching means which is arranged to switch between said transceiver means and said external antenna or said antenna arrangement upon manual extension or retraction of said external antenna.
In accordance with a further aspect of the invention, there is provided a radio communications handset comprising an internal antenna arrangement adapted to accommodate one or more handset components, said antenna arrangement comprising:
a ground plane;
a meandering radiating element extending in a series of opposing bends from a radio-frequency feed point and spaced a non-uniform distance from said ground plane;
wherein said handset component is located between said radiating element and said ground plane.
Preferably the handset component is an acoustic enhancing volume of free space located adjacent a loudspeaker. Alternatively or in addition the component may be another handset part such as an RF filter element located on the periphery of the volume.
In accordance with a further aspect of the invention, there is provided a radio communications handset internal antenna arrangement comprising:
a ground plane;
a meandering monopole extending in a series of opposing bends from a radio-frequency feed point and spaced a non-uniform distance from said ground plane.
The ground plane may be formed on the PCB, or an additional metallic plane may be formed perpendicular to the plane of the PCB which extends to a width corresponding to that containing the opposing bends of the meandering monopole.
Preferably the antenna arrangement further comprises a planar element connected to the free end of said monopole and extending back along and substantially parallel with said monopole.
The bends may be effected in more than one plane.
REFERENCES:
patent: 4021810 (1977-05-01), Urpo et al.
patent: 4679233 (1987-07-01), Richardson et al.
patent: 4860020 (1989-08-01), Wong et al.
patent: 4958382 (1990-09-01), Imanishi
patent: 5696517 (1997-12-01), Kawahata et al.
patent: 5710987 (1998-01-01), Paulick
patent: 5943019 (1999-08-01), Kawahata et al.
patent: 0777293A1 (1997-06-01), None
patent: WO 93/12559 (1993-06-01), None
patent: WO 96/27219 (1996-09-01), None
patent: WO 96/38882 (1996-12-01), None
Amos Sonya
Dalby Anthony
Gwynn Peter
Llewellyn Ian Paul
Robson Julius George
Chen Shih-Chao
Lee, Mann, Smith, McWilliam Sweeney & Ohlson
Nortel Networks Limited
Wong Don
LandOfFree
Radio communications handset antenna arrangements does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Radio communications handset antenna arrangements, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Radio communications handset antenna arrangements will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2617747