U.S. patent application number 11/445942 was filed with the patent office on 2007-02-15 for method for controlling antennas of mobile terminal device and such a mobile terminal device.
This patent application is currently assigned to Lenovo (Singapore) Pte. Ltd.. Invention is credited to Takeshi Asano, Kazuo Fujii, Masaharu Itoh, Kozo Matsunaga.
Application Number | 20070037619 11/445942 |
Document ID | / |
Family ID | 36694772 |
Filed Date | 2007-02-15 |
United States Patent
Application |
20070037619 |
Kind Code |
A1 |
Matsunaga; Kozo ; et
al. |
February 15, 2007 |
Method for controlling antennas of mobile terminal device and such
a mobile terminal device
Abstract
A method for controlling antennas of a mobile terminal device
such as a laptop PC and a handheld PC without degrading
communication speed or quality and a mobile terminal device having
such control means are provided. The method comprises determining
the usage of the mobile terminal device, determining an antenna to
be disabled among the plurality of antennas according to the usage
that is determined by the determining of usage, and disabling the
antenna disabling of which is determined by determining of an
antenna to be disabled, wherein the determining of usage determines
usage based on the display orientation of the display unit of the
mobile terminal device.
Inventors: |
Matsunaga; Kozo;
(Yokohama-shi, JP) ; Asano; Takeshi; (Atsugi-shi,
JP) ; Itoh; Masaharu; (Yamato-shi, JP) ;
Fujii; Kazuo; (Yokohama-shi, JP) |
Correspondence
Address: |
FERENCE & ASSOCIATES
409 BROAD STREET
PITTSBURGH
PA
15143
US
|
Assignee: |
Lenovo (Singapore) Pte.
Ltd.
|
Family ID: |
36694772 |
Appl. No.: |
11/445942 |
Filed: |
June 3, 2006 |
Current U.S.
Class: |
455/575.7 |
Current CPC
Class: |
H04B 1/3838 20130101;
H04B 7/0871 20130101; H01Q 3/24 20130101; H01Q 1/243 20130101; H04B
7/0689 20130101; H01Q 1/2291 20130101 |
Class at
Publication: |
455/575.7 |
International
Class: |
H04M 1/00 20060101
H04M001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 3, 2005 |
JP |
2005-164280 |
Claims
1. A method for controlling a plurality of antennas of a mobile
terminal device, comprising: determining a usage of said mobile
terminal device; determining an antenna to be disabled among said
plurality of antennas according to the usage that is determined by
said determining of usage; and disabling the antenna, disabling of
which is determined by said determination of an antenna to be
disabled, wherein said determining of usage determines usage based
on a display orientation of a display unit of said mobile terminal
device.
2. The method according to claim 1, wherein said determining of
usage determines usage based on installation status that is
detected by an installation status sensing unit of said mobile
terminal device.
3. The method according to claim 2, wherein said mobile terminal
device is a laptop PC or a handheld PC.
4. A method for controlling a plurality of antennas of a mobile
terminal device, comprising: determining a usage of said mobile
terminal device; determining an antenna to be disabled among said
plurality of antennas according to the usage that is determined by
said determining of usage; and disabling the antenna, disabling of
which is determined by said determining of an antenna to be
disabled, wherein said determining of usage determines usage based
on an orientation of holding said mobile terminal device that is
detected by a holding orientation sensing unit of said mobile
terminal device.
5. A mobile terminal device having a plurality of antennas,
comprising: usage determination means for determining a usage of
said mobile terminal device; disabling determination means for
determining an antenna to be disabled among said plurality of
antennas according to usage that is determined by said usage
determination means; and disabling means for disabling the antenna,
disabling of which is determined by said disabling determination
means, wherein said usage determination means determines usage
based on a display orientation of a display unit of said mobile
terminal device.
6. The mobile terminal device according to claim 5, wherein said
usage determination means determines usage based on installation
status that is detected by an installation status sensing unit of
said mobile terminal device.
7. The mobile terminal device according to claim 6, wherein said
mobile terminal device is a laptop PC or a handheld PC.
8. A mobile terminal device having a plurality of antennas,
comprising: usage determination means for determining a usage of
said mobile terminal device; disabling determination means for
determining an antenna to be disabled among said plurality of
antennas according to usage that is determined by said usage
determination means; and disabling means for disabling the antenna,
disabling of which is determined by said disabling determination
means, wherein said usage determination means determines usage
based on an orientation of holding said mobile terminal device that
is detected by a holding orientation sensing unit of said mobile
terminal device.
Description
CLAIM FOR PRIORITY
[0001] This application claims priority from Japanese Patent
Application No. 2005-164280, filed Jun. 3, 2005, and which is
hereby incorporated by reference as if fully set forth herein.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to a method for controlling
the antennas of a mobile terminal device that has a plurality of
antennas, for example. More particularly, the present invention
relates to a method for controlling antennas in accordance with the
usage of such a mobile terminal device and to such a mobile
terminal device.
[0003] In recent years, the effects of electromagnetic wave emitted
from mobile terminal devices on the human body has been a subject
of considerable interest, and technologies for reducing absorption
of electromagnetic wave into the human body have become an issue in
designing mobile terminal devices. For example, in the United
States, a standard has been established that prescribes the
acceptable value of Specific Absorption Rate (SAR), which is a
measure of electric energy of electromagnetic wave absorbed by the
human body, to be under 1.6 W/kg.
[0004] In such a circumstance, for a mobile terminal device that
has a plurality of antennas for wireless communication, a method
has been proposed for always selecting an antenna with better SAR
properties for use from the plurality of antenna on such a device.
For example, Japanese Unexamined Patent Publication No. 2003-283393
discloses a method for switching between "a first antenna that is
designed to obtain preferable SAR properties in all usages" and "a
second antenna that is not so designed" and using the selected one
in accordance with how a mobile terminal device (e.g., a mobile
phone) is being used for the purpose of reducing SAR associated
with a mobile terminal device.
[0005] Specifically, the method switches between the first antenna
and the second antenna according to the usage of the mobile
terminal device, such as whether the external data terminal is in
use or not, whether handsfree communication is being carried out or
not, whether or not the external audio communication terminal is in
use, whether the camera is in use or not, whether image
communication is being carried out, or whether packet communication
is being carried out. In addition, a technique that is based on a
method for determining the distance between the mobile terminal
device and the human body and a technique based on a method for
detecting opening/closing of the housing of the mobile terminal
device have been also disclosed. Thus, the method disclosed by
Japanese Unexamined Patent Publication No. 2003-283393 is intended
to improve SAR properties while avoiding degradation of
communication speed and quality of a mobile terminal device as much
as possible.
[0006] However, another issue arises when such a method is applied
to a laptop PC or handheld PC, for example.
[0007] More specifically, a mobile phone can have various usages,
that is, a mobile phone may be used as a data communication
terminal, audio communication terminal, camera, image communication
terminal, packet communication terminal and so on as mentioned
above. Thus, it is necessary to employ a complex control method
such as the one described above to select an antenna according to
such usages. In addition, such a device has to be small in size for
use as a mobile phone. For those reasons, even if a terminal has a
plurality of antennas, when the terminal is used in close contact
with the human body such as for voice call, it could be difficult
to reduce SAR unless, transmission output itself is reduced for any
antenna at any position selected. Thus, in such a case, with the
method disclosed by Japanese Unexamined Patent Publication No.
2003-283393, it is necessary to select an antenna that is designed
to limit transmission output in order to maintain preferable SAR
properties. In this case, degradation of communication speed and
quality of the mobile phone has to be accepted.
[0008] On the other hand, a laptop PC or handheld PC does not have
so many usages as a mobile phone. In addition, size of such mobile
terminal devices for use as a terminal is less restricted. With
these features, control could become too complex if the antenna
control method for a mobile phone terminal device described above
is applied to a laptop PC or a handheld PC without modification. To
realize such complex control, many devices such as sensors are
required for detecting how the terminal device is used. As a
result, the mechanism of a mobile terminal device itself becomes
complex and there would be more causes of trouble accordingly. In
addition, when an antenna with its output limited low is selected,
communication speed or quality of the mobile terminal device
degrades.
[0009] In view of such circumstances, it is desirable to provide a
method for controlling antennas without degrading communication
speed or quality of a mobile terminal device such as a laptop PC
and a handheld PC as well as a mobile terminal device having such
control means.
SUMMARY OF THE INVENTION
[0010] The present invention provides a method for controlling a
plurality of antennas of a mobile terminal device, comprising
determining the usage of the mobile terminal device, determining an
antenna to be disabled among the plurality of antennas according to
the usage that is determined by the determination of usage, and
disabling the antenna disabling of which is determined by
determination of an antenna to be disabled, wherein the determining
of usage determines usage based on the display orientation of the
display unit of the mobile terminal device.
[0011] Alternatively, the determining of usage determines usage
based on the orientation of holding the mobile terminal device that
is detected by a holding orientation sensing unit of the mobile
terminal device.
[0012] Alternatively, the determining of usage determines usage
based on installation status detected by an installation status
sensing unit of the mobile terminal device.
[0013] According to the invention, an antenna to be disabled is
determined as appropriate from among a plurality of antennas
provided in accordance with the usage of a mobile terminal device.
The usage of the mobile terminal device is determined based on
display orientation on the display unit, the orientation of holding
the device, and combination of them and installation status. The
output of the plurality of antennas provided need not be
necessarily reduced. The method according to the invention controls
antennas of a laptop PC or a handheld PC appropriately, for
example.
[0014] According to the method of the invention, antennas of a
mobile terminal device can be controlled so as to reduce SAR on the
human body without degrading communication speed or quality. For
example, the method can control SAR adequately on a laptop PC or a
handheld PC among others.
[0015] For a better understanding of the present invention,
together with other and further features and advantages thereof,
reference is made to the following description, taken in
conjunction with the accompanying drawings, and the scope of the
invention will be pointed out in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 generally illustrates a physical configuration of a
mobile terminal device 1 according to an example of a preferred
embodiment of the invention;
[0017] FIG. 2 illustrates movement of a housing of the mobile
terminal device 1 according to an example of the preferred
embodiment of the invention;
[0018] FIG. 3 illustrates movement of a housing of the mobile
terminal device 1 according to an example of the preferred
embodiment of the invention;
[0019] FIG. 4 illustrates movement of a housing of the mobile
terminal device 1 according to an example of the preferred
embodiment of the invention;
[0020] FIG. 5 illustrates the relation between the display
orientation of the display unit 11 and antenna control of the
mobile terminal device 1 according to an example of the preferred
embodiment of the invention;
[0021] FIG. 6 illustrates the relation between the display
orientation of the display unit 11 and antenna control of the
mobile terminal device 1 according to an example of the preferred
embodiment of the invention;
[0022] FIG. 7 illustrates the relation between the display
orientation of the display unit 11 and antenna control of the
mobile terminal device 1 according to an example of the preferred
embodiment of the invention;
[0023] FIG. 8 illustrates the relation between the display
orientation of the display unit 11 and antenna control of the
mobile terminal device 1 according to an example of the preferred
embodiment of the invention;
[0024] FIG. 9 shows a hardware configuration of the mobile terminal
device 1 according to an example of the preferred embodiment of the
invention;
[0025] FIG. 10 shows a functional configuration of the mobile
terminal device 1 according to an example of the preferred
embodiment of the invention;
[0026] FIG. 11 shows a functional configuration of the mobile
terminal device 1 according to another example of the preferred
embodiment of the invention;
[0027] FIG. 12 is a flow diagram illustrating the flow of antenna
control according to an example of the preferred embodiment of the
invention;
[0028] FIG. 13 is a flow diagram illustrating the flow of antenna
control according to an example of the preferred embodiment of the
invention; and
[0029] FIG. 14 is a flow diagram illustrating the flow of antenna
control according to an example of the preferred embodiment of the
invention.
DETAILED DESCRIPTION OF THE INVENTION
[0030] A preferred embodiment of the present invention will be
described with respect to drawings.
[0031] FIG. 1 generally illustrates a configuration of a mobile
terminal device 1 according to an example of a preferred embodiment
of the invention. The mobile terminal device 1 has two housings 14
and 15 that are approximately rectangular parallelpipeds. The
housing 14 has an input unit 10, and the housing 15 has a display
unit 11. Further, the housings 14 and 15 are connected by a joint
unit 13 at a point at the center of their edge, and can be moved in
the direction of opening/closing the housings. The housing 15 can
be rotated at least 180.degree. with the housing 15 perpendicular
to the housing 14. Thus, the mobile terminal device 1 may be used
as a usual laptop PC as shown in FIG. 1, or as a handheld PC that
has a touch panel input unit 16 and the like by rotating the
housing 15 at the joint unit 13 as shown in FIG. 2 and folding the
housing 15 with the display unit onto the housing 14 that has the
input unit 10 as illustrated in FIGS. 3 and 4.
[0032] Here, a laptop PC is not limited to such one shown in FIG.
1, but it may be a so-called portable personal computer that has
parts such as a CPU, memory, hard disk device, keyboard, display
panel and the like. Also, a handheld PC is not limited to such one
shown in FIG. 4, but it may be a so-called portable computer or an
information processing terminal that also has a CPU, memory, hard
disk device, touch panel, pen input panel or display panel as input
means. Further, devices falling within categories called electronic
organizer or PDA may be also included. Also, the terminal device
may include a keyboard as input means.
[0033] As shown in FIG. 5, the mobile terminal device 1 has a first
antenna 100 and a second antenna 110 on each of two sides of the
housing 15 that supports the display unit 11. These antennas are
connected to a wireless LAN card 120 and the antennas and the LAN
card operate in cooperation to realize communication means of the
mobile terminal device 1. The mobile terminal device 1 further
includes a display orientation rotation button 17 on the same
surface as the display unit 11 of the housing that supports the
display unit 11. By pressing the button 17, a user can change the
orientation of display on the display unit 11 by a predetermined
angle, e.g., 90.degree. and 180.degree.. The display orientation
rotation button 17 may be provided at any position on the housings
of the mobile terminal device 1 as long as it may be operated both
when the terminal device 1 is used as a laptop PC (FIG. 1, for
example) and as a handheld PC (FIG. 4, for example).
[0034] Further, the display orientation of the display unit 11 may
be automatically changed based on the difference in positional
relationship of the two housings for the case the terminal is used
as a laptop PC as shown in FIG. 1 and the case it is used as a
handheld PC as shown in FIG. 4.
[0035] FIG. 5 illustrates the display orientation of the mobile
terminal device 1 in a first portrait display mode. In an example
of the preferred embodiment of the invention, in this display mode,
it is determined that the second antenna 110 that is positioned
lower relative to the display orientation is closer to the user's
body, and the second antenna 110 is disabled in consideration of
the way the user holds the terminal device 1.
[0036] FIG. 6 illustrates the display orientation of the mobile
terminal device 1 in a second portrait display mode. The display
orientation in this mode is shifted 180.degree. from the first
portrait display mode shown in FIG. 5. The user of the mobile
terminal device 1 can switch between these display modes by
pressing the display orientation rotation button 17. In an example
of the preferred embodiment of the invention, in this display mode,
it is determined that both the first antenna 100 and second antenna
110 are away from the user's body and both the antennas are enabled
considering the way the user holds the terminal device 1. In this
case, an antenna with better use conditions is selected for use by
a known method conventionally employed.
[0037] Further, as illustrated in FIG. 7, in a first landscape
display mode of the mobile terminal device 1, the first antenna 100
positioned lower relative to the display orientation is considered
to be closer to the user's body considering how the user holds the
terminal device 1, and the first antenna 100 is disabled. When in a
second landscape display mode of the mobile terminal device 1 as
shown in FIG. 8, it is determined that both the first antenna 100
and second antenna 110 are away from the user's body considering
how the user holds the terminal device 1, and both the antennas are
enabled. In this case, an antenna with better use conditions is
selected for use by a known method conventionally employed.
[0038] Thus, according to the invention, an antenna positioned
lower relative to display orientation is considered to be closer to
the user's body and can be automatically disabled taking into
consideration how the user holds the terminal. Consequently, an
antenna closer to the hand or body of the user holding the mobile
terminal device I is disabled and only an antenna farther from the
user's hand or body is enabled, so that SAR on the human body can
be minimized while the user can use wireless communication all the
time.
[0039] Alternatively, an acceleration sensor may be included in the
housing of the mobile terminal device 1 and any of the four usages
shown in FIGS. 5-8 may be determined from the orientation of
holding the terminal that is detected by the acceleration sensor.
Specifically, if an antenna exists on a side that is determined to
be positioned downmost among the four sides of the housing, it is
determined that the antenna is closer to the user's body and is
disabled. In this case, the determination can be made without using
information on the display orientation on the display unit 11.
[0040] Further, the display orientation of the display unit may be
automatically changed according to the determination of the
vertical relationship of the housings. This allows the display
orientation of the display unit 11 to be changed and an antenna
more suitable for the display orientation to be selected without
the user pressing the display orientation rotation button 17
whenever the user changes the way of holding the mobile terminal
device 1.
[0041] Also, when the mobile terminal device 1 is connected to a
docking station (i.e., used as a laptop PC), the connection may be
detected by a sensor, and both the first and second antennas 100
and 110 may be enabled regardless of the display orientation by the
instruction for the terminal detected by an acceleration sensor. In
this case, an antenna with better use conditions would be selected
for use by a known method conventionally employed.
[0042] FIG. 9 illustrates a hardware configuration of the mobile
terminal device 1 of the invention. A control unit 140 controls the
entire mobile terminal device 1. The mobile terminal device 1 also
has a communication control unit 130 that includes an antenna
control unit 131 for controlling the first and second antennas 100
and 110. The antenna control unit 131 determines an antenna to be
disabled and stops the use of the antenna according to the
determination as described earlier.
[0043] The mobile terminal device 1 may include an acceleration
sensor 150. The mobile terminal device may also include a docking
sensor 160 for detecting whether the terminal device 1 is connected
to a docking station. Using detection result by these sensors, the
antenna control unit 131 controls the antennas in cooperation with
the control unit 140 as mentioned above. These pieces of hardware
are interconnected by a bus 180. Programs stored in a storage unit
170 are read out and executed as necessary by the control unit 140,
causing the pieces of hardware to cooperate to realize the various
means of the invention.
[0044] As can be readily appreciated by those skilled in the art,
the acceleration sensor 150 is available in various mechanisms,
such as one that is combination of piezoelectric ceramic device and
electrodes. When acceleration (gravitational acceleration in
resting state, for example) is externally applied to the
piezoelectric ceramic devices, the piezoelectric ceramic devices
distort to generate stress internally. The stress is converted to
electric signal (electric charge) with piezoelectric effect and the
direction and magnitude of the acceleration can be detected from
the electric signal. This allows the direction of the gravitational
acceleration to be detected in resting state, and the orientation
in which the mobile terminal device 1 is held can be calculated
from the direction.
[0045] FIG. 10 illustrates a functional configuration of the mobile
terminal device 1 according to an example of the preferred
embodiment of the invention. The control unit 140 controls the
entire mobile terminal device 1. The control unit 140 provides
various functions of the mobile terminal device 1 in conjunction
with the antenna control unit 131 for controlling the first and
second antennas 110 and 110, a built-in button controller 240 for
controlling built-in buttons such as the display orientation
rotation button 17, and a graphic controller 250 for controlling
the display unit 11. On an operating system (OS) 200, various user
applications such as a word processor can run. The OS 200 drives
various pieces of hardware via the control unit 140, antenna
control unit 131, built-in button controller 240, and graphic
controller 250 by way of kernel-level process groups that consist
of a built-in button driver 220, a graphic driver 230 and the
like.
[0046] In an example of the preferred embodiment of the invention,
when the user presses the display orientation rotation button 17 of
the mobile terminal device 1, the built-in button controller 240
senses the pressing. The built-in button controller 240 then
informs the OS 200 of the pressing via the built-in button driver
220. The OS 200 sends a command for rotating the screen by a
predetermined rotation angle (e.g., 90.degree.) to the graphic
controller 250 via the graphic driver 230. The graphic controller
250 receives the command and rotates the display orientation of the
display unit 11 (e.g., 90.degree.) accordingly. Further, upon
detecting the pressing of the display orientation rotation button
via the OS 200 and the like, the control unit 140 confirms the
display orientation of the display unit 11 to the OS 200. The OS
200 obtains information on display orientation from the graphic
controller 250 via the graphic driver 230. The control unit 140
obtains the information on display orientation from the OS 200,
determines whether to disable/enable the first and/or second
antennas based on the information on display orientation, and
executes the determination via the antenna control unit 131.
[0047] FIG. 11 illustrates a functional configuration of the mobile
terminal device 1 according to another example of the preferred
embodiment of the invention. As in FIG. 10, the control unit 140
controls the entire mobile terminal device 1. The control unit 140
provides various functions of the mobile terminal device 1 in
conjunction with the antenna control unit 131 for controlling the
first and second antennas 100 and 110, a device controller 270 for
controlling the acceleration sensor 150 and docking sensor 160, and
a graphic controller 250 for controlling the display unit 11. On
the operating system (OS) 200, various user applications such as a
word processor can run. The OS 200 drives various pieces of
hardware via the control unit 140, antenna control unit 131, device
controller 270, and graphic controller 250 or the like, by way of
kernel-level process groups that consist of the device driver 260
and graphic driver 230.
[0048] In another example of the preferred embodiment of the
invention, when the user changes the orientation of holding the
terminal, the acceleration sensor 150 detects the change. When the
change in holding orientation is detected, the change is informed
to the OS 200 via the device driver 260. The control unit 140 is
informed of the change by the OS 200, and based on the information
on the change, determines whether to disable/enable the first
and/or second antennas and executes the determination via the
antenna control unit 131.
[0049] Further, in yet another example of the preferred embodiment
of the invention, the docking sensor 160 senses the connection of
the mobile terminal device 1 to a docking station (not shown). In
this case, as with the acceleration sensor 150, the control unit
140 recognizes the connection and changes the display orientation
of the display unit 11 to the second landscape display mode shown
in FIG. 8 via the graphic controller 250. Further, the control unit
140 enables both the first and second antennas via the antenna
control unit 131. Here, an antenna with better use conditions is
selected for use by a known method conventionally employed.
[0050] FIG. 12 is a flow diagram illustrating the flow of antenna
control according to an example of the preferred embodiment of the
invention. First, the control unit 140 determines whether or not
the display orientation rotation button 17 has been pressed (step
S01). If it determines that the button has been pressed, the
control unit 140 queries the OS (operating system) running on the
mobile terminal device 1 about the display orientation of the
display unit 11 (step S02).
[0051] If the query returns the first portrait display mode shown
in FIG. 5 (step S03), the antenna control unit 131 disables the
second antenna 110 (step S04). On the other hand, the query returns
the second portrait display mode shown in FIG. 6 (step S05), the
antenna control unit 131 enables both the first and second antennas
100 and 110 (step S06). In the latter case, an antenna with better
use conditions is selected for use by a known method conventionally
employed.
[0052] If the query returns the first landscape display mode shown
in FIG. 7 (step S07), the antenna control unit 131 disables the
first antenna 100 (step S08). If the query returns the second
landscape display mode shown in FIG. 8 (step S09), the antenna
control unit 131 enables both the first and second antennas 100 and
110 (step S10). In the latter case, an antenna with better use
conditions is selected for use by a known method conventionally
employed.
[0053] In this manner, control starting from step S01 is repeated
until the use of the mobile terminal device ends (step S11).
[0054] FIG. 13 is a flow diagram illustrating the flow of antenna
control according to another example of the preferred embodiment of
the invention. First, the control unit 140 determines whether or
not the holding orientation of the mobile terminal device 1 has
changed (step S101). Then, if the control unit 140 determines that
the holding orientation has changed and that the second side shown
in FIG. 5 is at the bottom (step S103), the antenna control unit
131 disables the second antenna 110 (step S104). Meanwhile, if the
control unit 140 determines that the holding orientation has
changed and that the fourth side shown in FIG. 5 is at the bottom
(step S105), the antenna control unit 131 enables both the first
and second antennas 100 and 110 (step S106). In the latter case, an
antenna with better use conditions is selected for use by a known
method conventionally employed.
[0055] If the control unit 140 determines that the holding
orientation has changed and that the first side shown in FIG. 5 is
at the bottom (step S107), the antenna control unit 131 disables
the first antenna 100 (step S108). If the control unit 140
determines that the holding orientation has changed and that the
third side shown in FIG. 5 is at the bottom (step S109), the
antenna control unit 131 enables both the first and second antennas
100 and 110 (step S110). In the latter case, an antenna with better
use conditions is selected for use by a known method conventionally
used.
[0056] Control starting at step S101 is repeated in such a manner
until the use of the mobile terminal device ends (step S111).
[0057] FIG. 14 is a flow diagram illustrating the flow of antenna
control according to yet another example of the preferred
embodiment of the invention. Initially, the control unit 140
determines whether or not the mobile terminal device 1 has been
connected to a docking station (step S121). If the control unit 140
determines that the terminal is connected to the docking station,
the control unit 140 changes the display orientation of the display
unit 11 to the second landscape display mode of FIG. 8 (step S122),
and the antenna control unit 131 enables both the first and second
antennas 100 and 110 (step S123). Here, an antenna with better use
conditions is selected for use by a known method conventionally
employed.
[0058] Control starting at step S121 is repeated in such a manner
until use of the mobile terminal device ends (step S124).
[0059] Although the above embodiments describes a case where the
mobile terminal device 1 has two antennas, if the terminal device
has three or more antennas, any antenna that is positioned lower
relative to the display orientation of the display unit can be
disabled in the same way. Also, any antenna that is positioned
downmost as determined by an acceleration sensor can be disabled in
the same way as described above.
[0060] Also, although use of an antenna with its transmission
output reduced is not necessarily required in the preferred
embodiment of the invention, the invention is not intended to deny
the use of such an antenna. For example, it is also possible that
the terminal device has more antennas and transmission output of
some of the antennas is reduced.
[0061] If not otherwise stated herein, it is to be assumed that all
patents, patent applications, patent publications and other
publications mentioned and cited herein are hereby fully
incorporated by reference herein as if set forth in their entirety
herein.
[0062] While the embodiment of the present invention has been
described, the description only illustrates specific examples and
does not limit the invention particularly. Also, the operation
mentioned in the embodiment of the invention only illustrates
specific examples and the operation provided by the present
invention is not limited to that described in the embodiment of the
invention.
* * * * *