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Mobile Phone Patent Abstract
A mobile phone includes a main body, a cover member and an antenna
assembly having a radiating metal strip and a matching circuit.
The radiating metal strip has a feeding leg and a short-circuit
leg coupled electrically to the matching circuit in such a manner
that the latter provides impedance matching for the antenna assembly.
A switching unit couples the cover member pivotally on the main
body, and determines whether the mobile phone is in a first operating
mode or a second operating mode. Either in the first or second operating
mode, the antenna assembly in the mobile phone has similar characteristic
by virtue of the impedance matching provided by the matching circuit.
Mobile Phone Patent Claims
We claim:
1. An antenna assembly for use in a mobile phone for transmitting
and receiving wireless signals, the mobile phone including at least
one first base board and a switching unit for determining whether
the mobile phone is in a first operating mode or a second operating
mode, the antenna assembly comprising: a radiating metal strip fabricated
on the first base board, and having a feeding leg and a short-circuit
leg; a matching circuit fabricated on the first base board and coupled
electrically to the short-circuit leg in order to provide an impedance
matching for the antenna assembly; wherein, when the mobile phone
is disposed in the first operating mode, the switching unit causes
disengagement of the short-circuit leg with respect to the ground,
thereby turning the antenna assembly to a monopole type antenna,
and when the mobile phone is disposed in the second operating mode,
the switching unit causes engagement of the short-circuit leg with
respect to the ground, thereby turning the antenna assembly to an
inverted F-type antenna such that either in the first operating
mode or the second operating mode, the antenna assembly has similar
characteristic by virtue of the impedance matching provided by the
matching circuit.
2. The antenna assembly according to claim 1, wherein the antenna
assembly is allotted to a predetermined transmission frequency,
the radiating metal layer having a length equivalent to a quarter
of the predetermined transmission frequency.
3. The antenna assembly according to claim 1, wherein the matching
circuit has a .pi.-shaped configuration or T-shaped configuration.
4. The antenna assembly according to claim 1, wherein the mobile
phone is a foldable type.
5. The antenna assembly according to claim 4, wherein the foldable
mobile phone includes a lower member and an upper member coupled
pivotally to the lower member, the upper member having a display
panel.
6. The antenna assembly according to claim 5, wherein when the
mobile phone is disposed in the first operating mode, the upper
member is spaced apart from the lower member and when the mobile
phone is disposed in the second operating mode, the upper member
abuts against the lower member.
7. A mobile phone comprising: a lower member having a first base
board; an upper member disposed above the lower member, and having
a second base board; a switching unit for determining whether the
mobile phone is in a first operating mode or a second operating
mode; an antenna assembly fabricated on the first base board for
transmitting and receiving wireless signals, the antenna assembly
including a radiating metal strip fabricated on the first base board,
and having a feeding leg and a short-circuit leg; a matching circuit
fabricated on the first base board and coupled electrically to the
short-circuit leg in order to provide an impedance matching for
the antenna assembly, a signal-processing module for processing
outgoing and incoming wireless signals; wherein, when the mobile
phone is disposed in the first operating mode, the switching unit
causes disengagement of the short-circuit leg with respect to the
ground, thereby turning the antenna assembly to a monopole type
antenna, and when the mobile phone is disposed in the second operating
mode, the switching unit causes engagement of the short-circuit
leg with respect to the ground, thereby turning the antenna assembly
to an inverted F-type antenna such that either in the first operating
mode or the second operating mode, the antenna assembly has similar
characteristic by virtue of said impedance matching provided by
said matching circuit.
8. The mobile phone according to claim 7, wherein the antenna assembly
is allotted to a predetermined transmission frequency, the radiating
metal layer having a length equivalent to a quarter of the predetermined
transmission frequency.
9. The mobile phone according to claim 7, wherein the matching
circuit has a .pi.-shaped configuration or T-shaped configuration.
10. The mobile phone according to claim 7, wherein the mobile phone
is a foldable type.
11. An antenna assembly for use in a mobile phone for transmitting
and receiving wireless signals, the mobile phone including a lower
member, an upper member coupled pivotally to the lower member, and
a switching unit for determining whether the mobile phone is in
a first operating mode or a second operating mode, the antenna assembly
comprising: a radiating metal strip fabricated on the first base
board, and having a feeding leg and a short-circuit leg; and a matching
circuit fabricated on the first base board and coupled electrically
to the short-circuit leg in order to provide an impedance matching
for the antenna assembly; wherein, when the mobile phone is disposed
in the first operating mode, the upper member is spaced apart from
the lower member such that the switching unit causes disengagement
of the short-circuit leg with respect to the ground, thereby turning
the antenna assembly to a monopole type antenna, and when the mobile
phone is disposed in the second operating mode, the upper member
abuts against the lower member such that the switching unit causes
engagement of the short-circuit leg with respect to the ground,
thereby turning the antenna assembly to an inverted F-type antenna
such that either in the first operating mode or the second operating
mode, the antenna assembly has similar characteristic by virtue
of said impedance matching provided by said matching circuit.
12. The antenna assembly according to claim 11, wherein the antenna
assembly is allotted to a predetermined transmission frequency,
the radiating metal layer having a length equivalent to a quarter
of the predetermined transmission frequency.
13. The antenna assembly according to claim 11, wherein the matching
circuit has a .pi.-shaped configuration or T-shaped configuration.
14. The antenna assembly according to claim 11, wherein the mobile
phone is a foldable type.
Mobile Phone Patent Description
FIELD OF THE INVENTION
The present invention relates to an antenna assembly, more particularly
to a built-in antenna assembly for use in a foldable mobile phone
(generally known as flip cell phone).
BACKGROUND OF THE INVENTION
Due to rapid innovation in the electronic communication technology,
a mobile phone becomes an inevitable instrument in our daily life.
Without it, he or she feels loss in touch with his friends and relatives.
In order to achieve high reliability in the transmitting and receiving
signals, the quality and functionality of the antenna assembly play
a major role in the mobile phone. There are generally two types
of antenna assembly used in the mobile phone, i.e. built-in antenna
assembly (which is generally contained within the casing of the
mobile phone) or an exposed type (i.e. the antenna assembly projects
outwardly from the casing of the mobile phone). A mobile phone with
a built-in antenna assembly is preferred to when compared to ones
having an exposed antenna assembly, since the latter may accidentally
collides with an object, thereby rendering the ruin of the mobile
phone. In addition, the built-in antenna assembly provides more
attractive appearance. For aesthetic and portability reasons, the
mobile phone is generally constructed in compact size. It is therefore
the prime object of the manufacture to improve the functionality
of the quality of the antenna assembly in the mobile phone.
When a monopole antenna is used as the built-in antenna assembly
in the foldable mobile phone, the antenna assembly provides fine
transmitting ability. However, a clear area of the mobile phone
may affect the transmitting ability by of the antenna assembly (i.e.
The clear area is located under the antenna assembly of the mobile
phone without any metal material). When the mobile is in the folded
position, the clear area changes, thereby deviating the resonance
frequency and causing degradation of the signal transmission bandwidth.
Under this condition, the vertical direction of the transmission
characteristic of the antenna assembly gets worse.
Referring to FIG. 1A, an unfolded position of a conventional mobile
phone 10 is shown to include a lower printed circuit board 14, an
upper printed circuit board 16 and an antenna unit 12. The antenna
unit 12 is mounted on the lower printed circuit board 14, and includes
an insulated plate 122 and a radiating metal strip 120 that is responsible
for providing the resonance frequency of the antenna unit 12. A
flexible printed cable 18 interconnects and transmits signals between
the lower and upper printed circuit boards 14, 16.
FIG. 1B is a perspective view of the conventional mobile phone
10 in a folded position (shown in upside down configuration for
illustration), wherein the lower printed circuit board 14 is disposed
above the upper printed circuit board 16. Under this condition,
the volume of the vacuum chamber is altered by virtue of shielding
of the upper printed circuit board 16, thereby deviating the resonance
frequency and causing remarkable degradation of the signal transmission
bandwidth.
SUMMARY OF THE INVENTION
The object of the present invention is to provide a built-in antenna
assembly for use in a foldable mobile phone, the antenna assembly
has a unique structure to provide the similar characteristic when
the mobile phone is the first and second operating modes, i.e. whether
the mobile phone is in an unfolded or folded position.
Another object of the present invention is to provide a foldable
mobile phone having an antenna assembly which provides the similar
characteristic regardless of its positions, i.e. whether the mobile
phone is in an unfolded or folded position.
In one aspect of the present invention, an antenna assembly is
provided for use in a foldable mobile phone. The mobile phone includes
at least one first base board and a switching unit for determining
whether the mobile phone is in a first operating mode or a second
operating mode. The antenna assembly accordingly includes: a radiating
metal strip fabricated on the first base board and having a feeding
leg and a short-circuit leg; and a matching circuit fabricated on
the first base board and coupled electrically to the short-circuit
leg in order to provide impedance matching for the antenna assembly.
When the mobile phone is disposed in the first operating mode, the
switching unit causes disengagement of the short-circuit leg with
respect to the ground, thereby turning the antenna assembly to a
monopole type antenna, and when the mobile phone is disposed in
the second operating mode, the switching unit causes engagement
of the short-circuit leg with respect to the ground, thereby turning
the antenna assembly to an inverted F-type antenna such that either
in the first operating mode or the second operating mode, the antenna
assembly has similar characteristic by virtue of the impedance matching
provided by the matching circuit.
In another aspect of the present invention, a mobile phone is provided
to include: a lower member having a first base board; an upper member
disposed above the lower member, and having a second base board;
a switching unit for determining whether the mobile phone is in
a first operating mode or a second operating mode; and an antenna
assembly fabricated on the first base board for transmitting and
receiving wireless signals. The antenna assembly includes: a radiating
metal strip fabricated on the first base board, and having a feeding
leg and a short-circuit leg; a matching circuit fabricated on the
first base board and coupled electrically to the short-circuit leg
in order to provide impedance matching for the antenna assembly,
and a signal-processing module for processing outgoing and incoming
wireless signals. When the mobile phone is disposed in the first
operating mode, the switching unit causes disengagement of the short-circuit
leg with respect to the ground, thereby turning the antenna assembly
to a monopole type antenna. When the mobile phone is disposed in
the second operating mode, the switching unit causes engagement
of the short-circuit leg with respect to the ground, thereby turning
the antenna assembly to an inverted F-type antenna such that either
in the first operating mode or the second operating mode, the antenna
assembly has similar characteristic by virtue of the impedance matching
provided by the matching circuit.
In still another object of the present invention, an antenna assembly
is provided for use in a mobile phone in order to transmit and receive
wireless signals. The mobile phone includes a lower member, an upper
member coupled pivotally to the lower member, and a switching unit
for determining whether the mobile phone is in a first operating
mode or a second operating mode. The antenna assembly includes:
a radiating metal strip fabricated on the first base board, and
having a feeding leg and a short-circuit leg; and a matching circuit
fabricated on the first base board and coupled electrically to the
short-circuit leg in order to provide impedance matching for the
antenna assembly. When the mobile phone is disposed in the first
operating mode, the upper member is spaced apart from the lower
member such that the switching unit causes disengagement of the
short-circuit leg with respect to the ground, thereby turning the
antenna assembly to a monopole type antenna. When the mobile phone
is disposed in the second operating mode, the upper member abuts
against the lower member such that the switching unit causes engagement
of the short-circuit leg with respect to the ground, thereby turning
the antenna assembly to an inverted F-type antenna such that either
in the first operating mode or the second operating mode, the antenna
assembly has similar characteristic by virtue of the impedance matching
provided by the matching circuit.
BRIEF DESCRIPTION OF THE DRAWINGS
Other features and advantages of this invention will become more
apparent in the following detailed description of the preferred
embodiments of this invention, with reference to the accompanying
drawings, in which:
FIG. 1A is an unfolded view of a conventional mobile phone, illustrating
how an antenna assembly is mounted therein;
FIG. 1B is a perspective overturned view, illustrating how the
antenna assembly is mounted in the conventional mobile phone;
FIG. 2 is a perspective unfolded view of a foldable mobile phone
according to the present invention;
FIG. 3 is a perspective folded view of the mobile phone according
to the present invention;
FIGS. 4A and 4B respectively show a matching circuit of the mobile
phone of the present invention, the circuit having a .pi.-shaped
configuration or T-shaped configuration; and
FIGS. 5A, 5B, 5C and 5D respectively show four embodiments of the
antenna assembly employed in the mobile phone of the present invention.
DETAILED DESCRIPTIONS OF THE PREFERRED EMBODIMENTS
Referring to FIG. 2, a perspective unfolded view of the preferred
embodiment of a foldable mobile phone 20 (generally known as flip
cell phone) according to the present invention is shown to include
a lower member 22 (hereinafter the main body), an upper member 24
(hereinafter the cover member), a switching unit 26, and an antenna
assembly 30 (see FIG. 3).
FIG. 3 shows a folded position of the mobile phone 20 of the present
invention. As illustrated, the main body 22 has a first base board
220 generally made from dielectric material. The cover member 24
is disposed on and is coupled pivotally to the main body 22 via
the switching unit 26 in such a manner that the switching unit 26
can determine whether the mobile phone 20 is in a first operating
mode (i.e. the unfolded position, wherein the cover member 24 is
spaced apart from the main body 22 as shown in FIG. 2) or a second
operating mode (the folded position, wherein the cover member 24
abuts against the main body 22 as shown in FIG. 3). The cover member
24 has a second base board 240 and a display panel 28. A plurality
of electronic components (not visible) are mounted on the first
and second base boards 220, 240 in order to provide specific functions
of the mobile phone. A flexible printed cable (not visible) is used
for interconnecting the electronic components on the boards, and
since the structure of function of the same are not relevant feature
of the present invention, a detailed description thereof is omitted
herein for the sake of brevity.
In this embodiment, the first base board 220 has a dimension of
40.times.80 mm.sup.2 while the second base board 240 has a dimension
slightly smaller than the first base board 220. The switching unit
26 includes a projection 260 projecting outwardly from the cover
member 24 and a retention recess 262 formed in the main body 22
such that extension and not extension of the projection 260 with
respect to the retention recess 262 can determine the modes (i.e.
folded or unfolded position) of the mobile phone of the present
invention.
The antenna assembly 30 is fabricated on the first base board 220
for transmitting and receiving wireless signals. The antenna assembly
30 includes a radiating metal strip 32, a matching circuit 34, and
a signal-processing module 36. The radiating metal strip 32 is fabricated
on an insulated plate 31 by screen-printing technology. The insulated
plate 31 has a dimension of 9.times.13.times.30 mm.sup.3, and is
mounted on the first base board 220. Tiny brass strip can serve
as the radiating metal strip 32. The radiating metal strip 32 has
a feeding leg 320 and a short-circuit leg 322. The feeding leg 320
is used for coupling electrically the signal-processing module 36
in such a manner that the signal-processing module 36 can process
the outgoing and incoming radio signals by utilizing the embedded
electrical circuits (such as wave-filtering circuit, amplifier circuit).
The short-circuit leg 322 has one end coupled to the radiating metal
strip 32 and the other end coupled to the matching circuit 34 so
that the latter provides an impedance matching for the antenna assembly
30.
The antenna assembly 30 is preferably allotted to a predetermined
transmission frequency. The radiating metal strip 32 is constructed
in such a manner to have a length equivalent to a quarter of the
predetermined transmission frequency. In one embodiment of the present
invention, the matching circuit 34 has a .pi.-shaped configuration
or T-shaped configuration. As illustrated in FIGS. 4A and 4B, the
.pi.-shaped matching circuit 34 includes some passivated components
P1-P3 (such as resistor, capacitor or inductor and a combination
of two or three elements). The aforesaid elements are used for adjusting
the impedance matching of the antenna assembly 30. The person known
in the art can various modifications can be used to achieve the
same effect, it is hope that the scope of the present invention
should not be limited only to the passivated element.
When the mobile phone 20 of the present invention is disposed in
the first operating mode (i.e. unfolded position), the switching
unit 26 causes disengagement of the short-circuit leg with respect
to the ground, thereby turning the antenna assembly 30 to a monopole
type antenna, and when the mobile phone is disposed in the second
operating mode (i.e. folded position), the switching unit 26 causes
engagement of the short-circuit leg with respect to the ground,
thereby turning the antenna assembly 30 to an inverted F-type antenna.
Under this condition, whether the mobile phone 20 of the present
invention is in the first operating mode or the second operating
mode, the antenna assembly has similar characteristic (such as resonance
frequency, bandwidth, the impedance matching of 50 ohms) by virtue
of the impedance matching provided by the matching circuit 34.
An important aspect to note is that though the foldable mobile
phone is illustrated in the present invention, but the antenna assembly
30 can be employed to several other types of mobile phones. It is
therefore hope that scope and spirit of the present invention should
encompass other modifications as well.
FIGS. 5A, 5B, 5C and 5D respectively show different mounting designs
in the mobile phones, wherein in FIGS. 5A and 5B, the antenna assembly
30 is mounted on the insulated plate of the first base board 220
in the main body at the upper and lower portions thereof. In FIGS.
5C and 5D, the antenna assembly 30 is mounted on the insulated plate
of the second base board 240 in the cover member at the upper and
lower portions thereof.
In summary, by virtue of presence of the antenna assembly 30 in
the mobile phone 20 of the present invention, the latter possesses
the similar characteristic in the folded and unfolded positions,
thereby eliminating the occurrence of accidental collision of the
exposed antenna assembly with an object as encountered during use
of the conventional mobile phone.
While the invention has been described in connection with what
is considered the most practical and preferred embodiments, it is
understood that this invention is not limited to the disclosed embodiments
but is intended to cover various arrangements included within the
spirit and scope of the broadest interpretation so as to encompass
all such modifications and equivalent arrangements.
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