Published patent 10-1185681
`
` (19) Korean Intellectual Property Office (KR)
`(12) Publication of Registered Patent (B1)
`
`(45) Publication Date
`(11) Registration No.
`(24) Registration Date
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`September 24, 2012
`10-1185681
`September 18, 2012
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`(51)
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`(21)
`(22)
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`(56)
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`International Patent Classification (Int. Cl.)
`H01Q 7/00 (Jan. 2006) H01Q 1/24 (Jan. 2006)
`H02J 17/00 (Jan. 2006)
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`Application No.
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`Application date
`Examination request date
`Prior art search documents
`KR1020110035196 A
`KR1020050019926 A
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`10-2011-0055073
`June 8, 2011
`June 8, 2011
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`(73)
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`(72)
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`(74)
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`Patentee
`CIDT Co., Ltd.
`#1107 (Partners Tower 1, Gasan-dong), 83, Gasan-digital 1-
`ro, Geumcheon-gu, Seoul
`Inventor
`KIM, Seon-Seob
`#117-601 (Ujangsan Hillstate Apt., Naebalsan-dong), 348,
`Gangseo-ro, Gangseo-gu, Seoul
`Agent
`JANG, Han-Jong
`
`Total number of claims: Total of 5 claims
`Examiner: BYUN, Jong-Gil
`(54) Title of Invention ANTENNA FOR BOTH NON-CONTACT CHARGING AND NEAR FIELD WIRELESS
`COMMUNICATION IN MOBILE COMMUNICATION TERMINAL
`(57) Abstract
`
`An antenna for both non-contact charging and near field wireless communication in a mobile communication terminal
`according to the present invention comprises a coil unit (11) wired in a spiral shape, a first terminal (12) formed at one end of
`the coil unit (11), a second terminal (13) formed on the other end of the coil unit (11), and a third terminal (14) drawn out from
`the coil unit (11) between the first terminal (12) and the second terminal (13), wherein the coil unit (11) between the first
`terminal (12) and the second terminal (13) generates an induced electromotive force of a frequency for non-contact charging,
`and the coil unit (11) between the first terminal (12) and the third terminal (14) has a characteristic of generating an induced
`electromotive force of a frequency for NFC, and comprises an antenna unit (10) installed in the battery cover (3) of a mobile
`communication terminal (2); a non-contact charging circuit (20) connected to the first terminal (12) and the second terminal
`(13) to realize the non-contact charging through the antenna unit (10) and installed in the main body (4) of the mobile
`communication terminal (2); and an NFC circuit (30) connected to the first terminal (12) and the third terminal (14) to realize
`the NFC through the antenna unit (10) and installed in the main body (4) of the mobile communication terminal (2).
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`Representative figure - Fig. 2
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`Page 1 of 23
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`SAMSUNG EXHIBIT 1007
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`

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`Published patent 10-1185681
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`Scope of claims
`
`Claim 1
`
`An antenna for both non-contact charging and near field wireless communication in a mobile communication terminal comprising
`
`a coil unit (11) wired in a spiral shape, a first terminal (12) formed at one end of the coil unit (11), a second terminal (13) formed on
`the other end of the coil unit (11), and a third terminal (14) drawn out from the coil unit (11) between the first terminal (12) and the
`second terminal (13), wherein the coil unit (11) between the first terminal (12) and the second terminal (13) generates an induced
`electromotive force of a frequency for non-contact charging, and the coil unit (11) between the first terminal (12) and the third terminal
`(14) has a characteristic of generating an induced electromotive force of a frequency for NFC, and comprising an antenna unit (10)
`installed in the battery cover (3) of a mobile communication terminal (2);
`
`a non-contact charging circuit (20) connected to the first terminal (12) and the second terminal (13) to realize the non-contact charging
`through the antenna unit (10) and installed in the main body (4) of the mobile communication terminal (2); and
`
`an NFC circuit (30) connected to the first terminal (12) and the third terminal (14) to realize the NFC through the antenna unit (10)
`and installed in the main body (4) of the mobile communication terminal (2).
`
`Claim 2
`
`The antenna for both non-contact charging and near field wireless communication in a mobile communication terminal of claim 1
`further comprising
`
`a switch unit (40) for activating or deactivating the non-contact charging by selectively connecting the first terminal (12) to the non-
`contact charging circuit (20) and for activating or deactivating the NFC by selectively connecting the first terminal (12) to the NFC
`circuit (30);
`
`a detection unit (50) for detecting the approach to a non-contact charger by using a coupling circuit (51) to recognize a frequency
`generated when the mobile communication terminal (2) approaches the non-contact charger; and
`
`a control unit (60) in which the switch unit (40) connects the first terminal (12) to the non-contact charging circuit (20) to activate the
`non-contact charging when the detection unit (50) recognizes the frequency for non-contact charging and, otherwise, the switch unit
`(40) connects the first terminal (12) to the NFC circuit (30) to activate the NFC.
`
`Claim 3
`
`The antenna for both non-contact charging and near field wireless communication in a mobile communication terminal of claim 2,
`
`wherein the antenna unit (10) gets connected to the non-contact charging circuit (20) when the power of the mobile communication
`terminal (2) is off;
`
`the antenna unit (10) gets connected to the non-contact charging circuit (20) when the power of the mobile communication terminal
`(2) is on, and the NFC is in non-use mode; and
`
`the antenna unit (10) gets connected to the NFC circuit (30) when the power of the mobile communication terminal (2) is on, and the
`NFC is in use mode.
`
`Claim 4
`
`The antenna for both non-contact charging and near field wireless communication in a mobile communication terminal of claim 1
`further comprising
`
`a low pass filter (70) installed between the first terminal (12) and the second terminal (13) and the non-contact charging circuit (20)
`to transmit only a frequency below a certain level including the frequency for the non-contact charging to the non-contact charging
`circuit (20); and
`
`a band pass filter (80) installed between the first terminal (12) and the third terminal (14) and the NFC circuit (30) to transmit a
`frequency band of a certain range including the frequency for the NFC to the NFC circuit (30).
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`Published patent 10-1185681
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`Claim 5
`
`An antenna for both non-contact charging and near field wireless communication in a mobile communication terminal comprising
`
`an antenna unit (10) comprising a coil unit (11) wired in a spiral shape, a first terminal (12) formed at one end of the coil unit (11),
`and a second terminal (13) formed on the other end of the coil unit (11), having a characteristic of generating an induced electromotive
`force of a frequency for non-contact charging and an induced electromotive force of a frequency for NFC, and installed in the battery
`cover (3) of a mobile communication terminal (2);
`
`a non-contact charging circuit (20) connected to the first terminal (12) and the second terminal (13) to realize the non-contact charging
`through the antenna unit (10) and installed in the main body (4) of the mobile communication terminal (2);
`
`an NFC circuit (30) connected to the first terminal (12) and the second terminal (13) to realize the NFC through the antenna unit (10)
`and installed in the main body (4) of the mobile communication terminal (2);
`
`a low pass filter (70) installed between the first terminal (12) and the second terminal (13) and the non-contact charging circuit (20)
`to transmit only a frequency below a certain level including the frequency for the non-contact charging to the non-contact charging
`circuit (20); and
`
`a band pass filter (80) installed between the first terminal (12) and the second terminal (13) and the NFC circuit (30) to transmit a
`frequency band of a certain range including the frequency for the NFC to the NFC circuit (30).
`
`Specification
`Technical field
`[0001] The present invention relates to an antenna for non-contact charging and near field wireless communication equipped on a
`mobile communication terminal.
`
`Background art
`
`[0002] A power supply is required to operate various mobile communication terminals represented by a mobile phone and for this
`purpose, a battery needs to be installed, and a multi-use rechargeable battery is widely used instead of a single-use battery as the
`battery for mobile communication terminals.
`
`[0003] Traditionally, the wired charging method has been widely used for charging batteries for mobile communication terminals, but
`wired charging not only limits mobility, which is the greatest advantage of a mobile communication terminal, but also has a problem
`in that the charging performance deteriorates due to aging of the charging terminal caused by repeated detachment.
`
`[0004] Due to this background, a non-contact (wireless) charging method has been introduced for charging a mobile phone, which is
`the representative mobile communication terminal.
`
`[0005] The principle of the most common non-contact charging is induced current, and according to this principle, when a mobile
`phone with a built-in secondary coil is placed on top of the primary coil installed in the non-contact charger, an induced electromotive
`force is generated in a frequency band of several hundred kHz (e.g., 300 kHz or less) between the primary and secondary coils,
`charging the battery of the mobile phone.
`
`[0006] Such non-contact charging had a problem in that it was not compatible with each other because various communication
`methods were used for each developer company but recently, international standardization has been achieved through the WPC
`(Wireless Power Consortium).
`
`[0007] As such, to apply the non-contact charging to the mobile communication terminal, a coil capable of generating an induced
`electromotive force, that is, a loop antenna in the form of a spiral coil (hereinafter referred to as an antenna) is required.
`
`[0008] In general, an antenna for non-contact charging is installed on the battery cover of a mobile phone and recently, as the charging
`circuit to which the antenna is connected became miniaturized and incorporated into the body of the mobile phone, only the antenna
`(unit) remains on the battery cover.
`
`[0009] Meanwhile, separate from the environment of non-contact charging, the wireless environment of RFID (Radio Frequency
`Identification: wireless identification) is widely used in mobile communication terminals and for example, when an NFC chip that
`realizes Near Field Communication (NFC) is installed in a mobile phone, equipped with a non-contact smart card such as a USIM
`card, and brought nearby an external RF reader, the information of the USIM card of the mobile phone is read by the RF reader by
`near field communication and the necessary information is recorded, which realizes the equipped function (e.g. electronic money
`function) such as an electronic money function.
`
`[0010] In this case, the information exchange between the NFC chip and the RF reader is accomplished by supplying power for
`operating the USIM card by induced electromotive force at 13.56 MHz between the primary coil (antenna) installed in the RF reader
`and the coil of the NFC chip installed in the mobile phone.
`
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`Published patent 10-1185681
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`[0011] Furthermore, the NFC chip installed in mobile phones has been developed to function as an RFID reader as well to read the
`information recorded on an external RFID tag. When the NFC chip operates as an RF reader, the antenna (coil) connected to the NFC
`chip acts as a primary coil to transmit power, and an induced electromotive force is generated from the coil (antenna) installed on an
`external RFID tag, allowing wireless communication to be realized.
`
`[0012] In other words, to apply the RFID system (NFC) to a mobile communication terminal, a loop antenna in the form of a spiral
`coil capable of generating an induced electromotive force is required. An antenna for NFC is also installed on the battery cover or
`battery.
`
`[0013] As a result, to equip both a non-contact charging function and a near field wireless communication function in a mobile
`communication terminal represented by a mobile phone, two antennas (coils) for inducing an electromotive force to each are required,
`and therefore, two antennas are equipped on the battery cover.
`
`[0014] Fig. 5 is a schematic diagram of the antenna connection for non-contact charging and near field wireless communication
`applied to a mobile phone.
`
`[0015] As illustrated, an antenna for non-contact charging (120) and an antenna for NFC chip (130) are installed in the cover (110) of
`the battery, and to connect both ends of these two antennas to a charging circuit (220) and an NFC circuit (230) installed on the main
`board (210) of the mobile phone, the main board (210) requires a total of four terminals, two antenna terminals (WC+, WC-) for
`WPC-based non-contact charging, and two antenna terminals (NFC+, NFC-) for NFC. Reference numeral 101 indicates a non-contact
`charger.
`
`Disclosure of invention
`
`Problem to be solved
`
`[0016] The object of the present invention is to, in relation to a mobile communication terminal equipped with both non-contact
`charging (WPC) and near field wireless communication (NFC), unify the antennas required for non-contact charging and near field
`wireless communication from two to one, and also, make it possible to use the antenna by selectively activating it for non-contact
`charging or for near field wireless communication depending on the use mode of non-contact charging and near field wireless
`communication, thereby reducing the burden of antenna installation for non-contact charging and near field wireless communication
`in a mobile communication terminal.
`
`Means to solve the problem
`
`[0017] According to the present invention, an antenna for both non-contact charging and near field wireless communication in a
`mobile communication terminal is provided.
`
`[0018] The antenna for combined use according to the first embodiment of the present invention comprises an antenna unit, a contact
`charging circuit, and an NFC circuit.
`
`[0019] The antenna unit comprises a coil unit wired in a spiral shape, a first terminal formed at one end of the coil unit, a second
`terminal formed on the other end of the coil unit, and a third terminal drawn out from the coil unit between the first terminal and the
`second terminal. The coil unit between the first terminal and the second terminal generates an induced electromotive force of a
`frequency for non-contact charging, and the coil unit between the first terminal and the third terminal has a characteristic of generating
`an induced electromotive force of a frequency for NFC. The antenna unit is installed in the battery cover of a mobile communication
`terminal.
`
`[0020] The non-contact charging circuit is connected to the first terminal and the second terminal to realize the non-contact charging
`through the antenna unit and installed in the main body of the mobile communication terminal.
`
`[0021] The NFC circuit is connected to the first terminal and the third terminal to realize the NFC through the antenna unit and
`installed in the main body of the mobile communication terminal.
`
`[0022] Preferably, the antenna for combined use of the first embodiment according to the present invention further comprises a switch
`unit, a detection unit, and a control unit.
`
`[0023] The switch unit activates or deactivates the non-contact charging by selectively connecting the first terminal to the non-contact
`charging circuit and activates or deactivates the NFC by selectively connecting the first terminal to the NFC circuit.
`
`[0024] A detection unit detects the approach to a non-contact charger by using a coupling circuit to recognize a frequency generated
`when the mobile communication terminal approaches the non-contact charger.
`
`[0025] In the control unit, the switch unit connects the first terminal to the non-contact charging circuit to activate the non-contact
`charging when the detection unit recognizes the frequency for non-contact charging and, otherwise, the switch unit connects the first
`terminal to the NFC circuit to activate the NFC.
`
`[0026] Preferably, in the antenna for combined use of the first embodiment, the antenna unit gets connected to the non-contact charging
`circuit when the power of the mobile communication terminal is off.
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`Published patent 10-1185681
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`[0027] Preferably, in the antenna for combined use of the first embodiment, the antenna unit gets connected to the non-contact charging
`circuit when the power of the mobile communication terminal is on, and the NFC is in non-use mode.
`
`[0028] Preferably, in the antenna for combined use of the first embodiment, the antenna unit gets connected to the NFC circuit when
`the power of the mobile communication terminal is on, and the NFC is in use mode.
`
`[0029] Preferably, the antenna for combined use of the first embodiment according to the present invention further comprises a low
`pass filter and a band pass filter.
`
`[0030] The low pass filter is installed between the first terminal) and the second terminal and the non-contact charging circuit to
`transmit only a frequency below a certain level including the frequency for the non-contact charging to the non-contact charging
`circuit.
`
`[0031] The band pass filter is installed between the first terminal and the third terminal and the NFC circuit to transmit a frequency
`band of a certain range including the frequency for the NFC to the NFC circuit.
`
`[0032] The antenna for combined use according to the second embodiment of the present invention comprises an antenna unit, a non-
`contact charging unit, an NFC circuit, a low pass filter, and a band pass filter.
`
`[0033] The antenna unit comprises a coil unit wired in a spiral shape, a first terminal formed at one end of the coil unit, and a second
`terminal formed on the other end of the coil unit, has a characteristic of generating an induced electromotive force of a frequency for
`non-contact charging and an induced electromotive force of a frequency for NFC, and is installed in the battery cover of a mobile
`communication terminal.
`
`[0034] The non-contact charging circuit is connected to the first terminal and the second terminal to realize the non-contact charging
`through the antenna unit and is installed in the main body of the mobile communication terminal.
`
`[0035] The NFC circuit is connected to the first terminal and the second terminal to realize the NFC through the antenna unit and is
`installed in the main body of the mobile communication terminal.
`
`[0036] The low pass filter is installed between the first terminal and the second terminal and the non-contact charging circuit to
`transmit only a frequency below a certain level including the frequency for the non-contact charging to the non-contact charging
`circuit (20).
`
`[0037] The band pass filter is installed between the first terminal and the second terminal and the NFC circuit to transmit a frequency
`band of a certain range including the frequency for the NFC to the NFC circuit.
`
`Effect of invention
`
`[0038] According to the antenna for combined use according to the present invention, in a mobile communication terminal equipped
`with both non-contact charging and near field wireless communication, it is possible to unify the antennas required for non-contact
`charging and near field wireless communication from two to one to use it for combined use, and use the antenna for combined use
`selectively for non-contact charging and for near field wireless communication according to the encountered situation, and thus, it is
`possible to reduce the burden of antenna installation for non-contact charging and near field wireless communication in a mobile
`communication terminal.
`
`Brief description of figures
`
`[0039] Fig. 1 is a schematic diagram of an exemplary three-terminal antenna unit applied to the present invention,
`
`Fig. 2 is a schematic diagram of an exemplary antenna for combined use according to the first embodiment of the present invention,
`
`Fig. 3 is a schematic diagram of another exemplary antenna for combined use according to the first embodiment of the present
`invention,
`
`Fig. 4 is a schematic diagram of an exemplary antenna for combined use according to the second embodiment of the present invention,
`and
`
`Fig. 5 is a schematic diagram of the antenna connection for non-contact charging and near field wireless communication applied to a
`mobile phone.
`
`Description of embodiments
`[0040] Hereinafter, the antenna for both non-contact charging and near field wireless communication in a mobile communication
`terminal according to the present invention will be described in detail with reference to the accompanying figures. The following
`embodiments are only for illustratively describing the antenna for combined use according to the present invention and are not
`intended to limit the scope of the present invention.
`[0041] First embodiment
`
`[0042] As illustrated in Figs. 1 to 3, the antenna for combined use (1) of the first embodiment according to the present invention
`comprises an antenna unit (10), a non-contact charging circuit (20), and an NFC circuit (30).
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`Published patent 10-1185681
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`[0043] As illustrated in Figs. 2 and 3, the antenna unit (10) is installed in the battery cover (3) of a mobile communication terminal
`(2), and the non-contact charging circuit (20) and the NFC circuit (30) are installed in the main body of the mobile communication
`terminal (2).
`
`[0044] The antenna unit (10), as illustrated in Fig. 1, as in the prior art in the related technical field, comprises a coil unit (11) in which
`a conductor, such as copper foil, is etched in the form of a spiral coil (loop form), a first terminal (12) formed at one end of the coil
`unit (11), and a second terminal (12) formed on the other end of the coil unit (11), but according to the characteristics of the present
`invention, further comprises a third terminal (14) drawn out from the coil unit (11) between the first terminal (12) and the second
`terminal (13).
`
`[0045] In other words, the antenna unit (10) applied to the present invention is a three-terminal antenna unit in which a third terminal
`(14) is additionally formed by tab-branching the coil unit (11) at an appropriate position between the first terminal (12) and the second
`terminal (13) at both ends.
`
`[0046] In this case, the coil unit (11) between the first terminal (12) and the second terminal (13) is formed to have a characteristic of
`generating an induced electromotive force of a frequency (300 kHz) for relatively long non-contact charging, and the branching
`position of the third terminal (14) is set to ensure that the coil unit (11) between the first terminal (12) and the third terminal (14)
`generates an induced electromotive force of a relatively short frequency (13.56 MHz) for NFC.
`
`[0047] As such, by additionally forming a third terminal between both terminals of the coil unit (11), it becomes possible to generate
`an induced electromotive force for non-contact charging and an induced electromotive force for NFC to a single antenna unit.
`
`[0048] The non-contact charging circuit (20) is a circuit designed to meet the WPC (Wireless Power Consortium) standards, and a
`circuit widely applied to non-contact charging can be applied to fit the present invention, and since the non-contact charging circuit
`itself is not directly related to the characteristics of the present invention, a detailed description thereof will be omitted.
`
`[0049] The first terminal (12) and the second terminal (13) are connected to the two terminals (21, 22) of the non-contact charging
`circuit (20) drawn out from the main body (4) of the mobile communication terminal (2) toward the battery cover (3), and the non-
`contact charging circuit (20) realizes non-contact charging through the antenna unit (10) between the first terminal and the second
`terminal.
`
`[0050] In other words, in the state in which non-contact charging is activated in the mobile communication terminal (2), the two
`terminals (21, 22) of the non-contact charging circuit (20) are connected to the first terminal (12) and the second terminal (13) of the
`antenna unit (10) to charge the battery by receiving power through an induced electromotive force with a frequency of 300 kHz
`between the antenna (not shown) built into a non-contact charger.
`
`[0051] The NFC circuit (30) is a circuit (chip) designed to conform to the standardized NFC and a circuit widely applied to NFC can
`be applied to fit the present invention, and since the NFC circuit (30) itself is not directly related to the characteristics of the present
`invention, a detailed description thereof will be omitted.
`
`[0052] The two terminals (31, 32) of the NFC circuit (30) drawn out from the main body (4) of the mobile communication (2) toward
`the battery cover (3) are connected to the first terminal (12) and the third terminal (14), and the NFC circuit (30) performs near field
`wireless communication in an RFID environment through the antenna unit (10) between the first terminal and the third terminal.
`
`[0053] In other words, in the state in which NFC is activated in the mobile communication terminal (2), the two terminals (31, 32) of
`the NFC circuit (30) are connected to the first terminal (12) and the third terminal (14) of the antenna unit (10) to execute near field
`wireless communication by receiving power through an induced electromotive force with a frequency of 13.56 MHz between the
`antenna (not shown) built into an electronic money reader, or the like.
`
`[0054] The antenna for combined use (1) according to the present invention is an antenna used for both non-contact charging and
`NFC, and since the non-contact charging and NFC in a mobile communication terminal are separate functions that do not have a
`correlation with each other, separate control for selecting whether to use the antenna unit (10) for the non-contact circuit (20) or to
`use it for the NFC circuit (30) cannot be performed.
`
`[0055] In other words, NFC can control ON/OFF to increase the charge-use time of the battery when it is not needed due to the
`characteristics of the function, but non-contact charging has a characteristic in that it should always be able to operate regardless of
`the ON/OFF of the power of the mobile communication terminal as long as the battery is equipped to the mobile communication
`terminal. However, since contact (wired) charging takes precedence over non-contact charging for the charging of the battery, the start
`and end of non-contact charging is determined by checking the presence or absence of contact charging and the remaining battery
`level.
`
`[0056] According to such characteristics of non-contact charging and NFC in a mobile communication terminal, the antenna for
`combined use of the present invention may require a selection means of the antenna unit for selecting whether to use the antenna unit
`(10) for non-contact charging or for NFC.
`
`[0057] Such selection of the antenna unit can be realized by the switch unit (40), the detection unit (50), and the control unit (60) as
`illustrated in Fig. 2.
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`Published patent 10-1185681
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`[0058] The switch unit (40) is a switch for activating or deactivating non-contact charging by selectively connecting the first terminal
`(12) to the non-contact charging circuit (20) or activating or deactivating NFC by selectively connecting the first terminal (12) to the
`NFC circuit (30).
`
`[0059] In the embodiment illustrated in Fig. 2, when the switching unit (40) is connected to the W terminal, the first terminal (12) gets
`connected to the non-contact charging circuit (20) and the second terminal (13) is always connected to the non-contact charging circuit
`(20), therefore non-contact charging gets activated, entering the state of being able to charge, and NFC gets deactivated.
`
`[0060] Conversely, when the switching unit (40) is connected to the N terminal, the first terminal (12) gets connected to the NFC
`circuit (30) and the third terminal (14) is always connected to the NFC circuit (30), therefore NFC gets activated, entering the state in
`which it can be used, and non-contact charging gets deactivated.
`
`[0061] The detection unit (50) serves to detect the approach of the mobile communication terminal to the non-contact charger by using
`the coupling circuit (51) to recognize the frequency generated when the mobile communication terminal (2) approaches the non-
`contact charger. In other words, when the user brings the mobile communication terminal (2) into the range (several hundred kHz) of
`the induced electromotive force of the non-contact charger for non-contact charging, the detection unit (50) detects the approach
`through the coupling circuit (51), allowing the charging intent of the user to be identified.
`
`[0062] The control unit (60) causes the switch unit (40) to connect the first terminal (12) to the non-contact charging circuit (20) to
`activate the non-contact charging when the detection unit (50) recognizes the frequency for non-contact charging, and in a different
`state, it causes the switch unit (40) to connect the first terminal (12) to the NFC circuit (30) to activate NFC.
`
`[0063] Ultimately, according to the antenna for combined use illustrated in Fig. 2, in normal times when non-contact charging is not
`performed, the antenna unit (10) is connected to the NFC circuit (30) to ensure that the NFC function can be used, and when a mobile
`communication terminal is brought close to a charger for charging, the antenna unit (10) gets connected to the non-contact charging
`circuit (20) to allow charging to be performed.
`
`[0064] In addition, when charging is completed or the mobile communication terminal is removed from the charger, the detection unit
`(50) detects this and the switching unit (40) gets connected to the N terminal under the control of the control unit (60), activating the
`NFC function again.
`
`[0065] In controlling the antenna for combined use of the present invention by the mobile communication terminal (2) to which the
`antenna for combined use according to the present embodiment described above is applied, NFC becomes unavailable when the power
`of the mobile communication terminal (2) is OFF, therefore it is preferable to control the antenna unit (10) to be connected to the non-
`contact charging circuit (20).
`
`[0066] In addition, when the power of the mobile communication terminal (2) is ON and the NFC is in use non-use mode, it is in a
`state of not using NFC, therefore it is preferable to control the antenna unit (10) to be connected to the non-contact charging circuit
`(20).
`
`[0067] Furthermore, when the power of the mobile communication terminal (2) is ON and NFC is in use mode, it is preferable to
`control the antenna unit (10) to be connected to the NFC circuit (30).
`
`[0068] As another example of the selection means of the antenna unit, as illustrated in Fig. 3, a low pass filter (70) and a band pass
`filter (80) may be comprised.
`
`[0069] The low pass filter (70), as illustrated in Fig. 3, is installed between the first terminal (12) and the second terminal (13) and the
`non-contact charging circuit (20), and filters only a frequency below a certain level (e.g., 500 kHz or lower) including the frequency
`for non-contact charging (300 kHz) and transmits it to the non-contact charging circuit (20).
`
`[0070] The band pass filter (80) is installed between the first terminal (12) and the third terminal (14) and the NFC circuit (30), and
`filters a frequency band of a certain range including the frequency for NFC (13.56 MHz) and transmits it to the NFC circuit (30).
`
`[0071] According to the embodiment of Fig. 3, it becomes possible to use non-contact charging and NFC at the same time without a
`switching circuit while using a single antenna unit (10) for combined use.
`
`[0072] Second embodiment
`
`[0073] As illustrated in Fig. 4, the antenna for combined use (1) of the second embodiment according to the present invention
`comprises an antenna unit (10), a non-contact charging circuit (20), an NFC circuit (30), a low pass filter (70), and a band pass filter
`(80).
`
`[0074] In the antenna for combined use of the present embodiment, the antenna unit (10) is also installed in the battery cover (3) of
`the mobile communication terminal (20) and the non-contact charging circuit (20), the NFC circuit