WO2008035893A1 - Booster circuit - Google Patents

Booster circuit Download PDF

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Publication number
WO2008035893A1
WO2008035893A1 PCT/KR2007/004497 KR2007004497W WO2008035893A1 WO 2008035893 A1 WO2008035893 A1 WO 2008035893A1 KR 2007004497 W KR2007004497 W KR 2007004497W WO 2008035893 A1 WO2008035893 A1 WO 2008035893A1
Authority
WO
WIPO (PCT)
Prior art keywords
signal
rejection filter
frequency band
booster circuit
mobile communication
Prior art date
Application number
PCT/KR2007/004497
Other languages
French (fr)
Inventor
Seok Dong Choi
Original Assignee
Lg Innotek Co., Ltd.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Lg Innotek Co., Ltd. filed Critical Lg Innotek Co., Ltd.
Priority to EP07808287A priority Critical patent/EP2052537A4/en
Publication of WO2008035893A1 publication Critical patent/WO2008035893A1/en

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N5/00—Details of television systems
    • H04N5/44—Receiver circuitry for the reception of television signals according to analogue transmission standards
    • H04N5/50—Tuning indicators; Automatic tuning control
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F3/00—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
    • H03F3/189—High-frequency amplifiers, e.g. radio frequency amplifiers
    • H03F3/19—High-frequency amplifiers, e.g. radio frequency amplifiers with semiconductor devices only
    • H03F3/191—Tuned amplifiers
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H5/00—One-port networks comprising only passive electrical elements as network components
    • H03H5/02—One-port networks comprising only passive electrical elements as network components without voltage- or current-dependent elements
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/06—Receivers
    • H04B1/10—Means associated with receiver for limiting or suppressing noise or interference
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/06—Receivers
    • H04B1/16—Circuits
    • H04B1/18—Input circuits, e.g. for coupling to an antenna or a transmission line
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F2200/00—Indexing scheme relating to amplifiers
    • H03F2200/114—Indexing scheme relating to amplifiers the amplifier comprising means for electro-magnetic interference [EMI] protection
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F2200/00—Indexing scheme relating to amplifiers
    • H03F2200/165—A filter circuit coupled to the input of an amplifier
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F2200/00—Indexing scheme relating to amplifiers
    • H03F2200/216—A coil being added in the input circuit, e.g. base, gate, of an amplifier stage
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F2200/00—Indexing scheme relating to amplifiers
    • H03F2200/225—Indexing scheme relating to amplifiers the input circuit of an amplifying stage comprising an LC-network
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F2200/00—Indexing scheme relating to amplifiers
    • H03F2200/237—A parallel resonance being added in series in the input circuit, e.g. base, gate, of an amplifier stage
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F2200/00—Indexing scheme relating to amplifiers
    • H03F2200/391—Indexing scheme relating to amplifiers the output circuit of an amplifying stage comprising an LC-network
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F2200/00—Indexing scheme relating to amplifiers
    • H03F2200/451—Indexing scheme relating to amplifiers the amplifier being a radio frequency amplifier
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F2200/00—Indexing scheme relating to amplifiers
    • H03F2200/75—Indexing scheme relating to amplifiers the amplifier stage being a common source configuration MOSFET

Definitions

  • the embodiment relates to a booster circuit.
  • a mobile communication terminal has employed a function of receiving ground wave broadcasting, and an orthogonal frequency division multiplexing (OFDM) scheme, which is a European scheme, has been employed as one of ground wave broadcasting schemes.
  • OFDM orthogonal frequency division multiplexing
  • This phenomenon may occur when the intensity of a GSM signal input through an antenna and a citizen band filter is greater than the intensity of an oscillating frequency of an oscillator of the ground wave tuner.
  • the oscillation of the ground wave tuner may be affected by the input GSM signal, so that an OSC killing phenomenon, in which the oscillator is not oscillated, occurs.
  • the intensity of a GSM signal (OdBm to +1OdBm) is much greater than the intensity of a broadcasting channel signal (-8OdBm to -25dBm). If a signal having a strong intensity like the GSM signal is input to a booster, the signal is coupled with the broadcasting signal in the booster to make another interference signal.
  • the booster amplifies the strong GSM signal, so that a stronger GSM signal causes an OSC killing phenomenon of killing an oscillator of a tuner, and a mutual interference exerts a fatal influence on a reception performance.
  • the embodiment provides a booster circuit capable of reducing frequency in- terference by weakening the intensity of an unnecessary signal input to an OFDM tuner. [9] The embodiment provides a booster circuit capable of preventing an OSC killing phenomenon of a tuner by excluding an unnecessary broadcasting channel signal when a broadcasting channel signal is received.
  • a booster circuit comprises a rejection filter for filtering a signal, which has a frequency band higher than a preset frequency band, among input signals, and a booster for receiving and amplifying a signal output from the rejection filter.
  • a mobile communication terminal comprises a booster circuit, which comprises a rejection filter filtering a signal, which has a frequency band higher than a frequency band of a broadcasting channel signal, among input signals, and a booster amplifying a signal output from the rejection filter, and a tuner which receives a signal output from the booster circuit.
  • OFDM tuner is weakened, thereby preventing frequency interference.
  • an unnecessary broadcasting signal is excluded when a broadcasting channel signal is received, thereby preventing an OSC killing phenomenon of a tuner.
  • FIG. 1 is a block diagram showing a booster circuit according to the embodiment
  • FIG. 2 is a circuit diagram showing a booster circuit according to the embodiment.
  • FIG. 3 is a graph showing the characteristic of a booster circuit according to the embodiment.
  • FIG. 1 is a block diagram showing a booster circuit according to the embodiment.
  • the booster circuit comprises a citizen band filter 11, a rejection filter 12, and a booster 13.
  • the citizen band filter 11 removes a citizen band signal from an input signal.
  • the input signal may be a broadcasting channel signal input through an antenna.
  • the rejection filter 12 attenuates a signal, which is out of a desired frequency band, in signals having passed through the citizen band filter 11.
  • the rejection filter 12 may be realized to attenuate a signal, which has a frequency band excluding a frequency band for a broadcasting signal, in broadcasting channel signals in which a citizen band signal is removed.
  • the attenuated signal may have a frequency band greater than the frequency band of the broadcasting channel signal.
  • the booster 13 amplifies a signal input thereto from the rejection filter 12.
  • the booster 13 may receive a broadcasting channel signal output from the rejection filter 12 to amplify the broadcasting channel signal.
  • a signal having an unnecessary frequency band is attenuated in the rejection filter 12, thereby inputting only a signal having a desired frequency band to the booster 13. Accordingly, a received broadcasting channel signal may be prevented from being affected by an external signal.
  • Such a booster circuit may be variously realized. For instance, a circuit shown in
  • FIG. 2 can be used as the booster circuit.
  • FIG. 2 is a circuit diagram showing the booster circuit according to the embodiment
  • FIG. 3 is a graph showing a characteristic of the booster circuit according to the embodiment.
  • the booster circuit comprises a citizen band filter 21, a rejection filter 22, and a booster 23.
  • the citizen band filter 21 comprises a capacitor C3 and an inductor L2.
  • the citizen band filter 21 removes a signal having a citizen band in the range of 26MHz to 30MHz, which is not used, from broadcasting channel signals input from an antenna ANT.
  • the rejection filter 22 comprises an inductor L3 and a capacitor C4.
  • the rejection filter 22 may be realized to attenuate a signal except for the broadcasting channel signal input from the citizen band filter 21.
  • the rejection filter 22 may be realized to attenuate a signal having a frequency band exceeding 900MHz, which is greater than a frequency band of the broadcasting channel signal.
  • the frequency band of the attenuated signal may be set by adjusting the capacity of the inductor L3 and the capacitor C4.
  • the rejection filter 22 can attenuate a GSM signal (948MHz) having the intensity within the range of OdBm to +1OdBm and employing a frequency band exceeding 900MHz as a central frequency.
  • FIG. 2 shows a case in which the rejection filter 22 comprises the inductor L3 and the capacitor C4.
  • the rejection filter 22 may be variously constructed if necessary.
  • the rejection filter 22 may comprise a single step filter as shown in FIG. 2 or a multi-step filter.
  • the rejection filter 22 may have a structure in which a plurality of filters including an inductor and a capacitor are serially connected to each other.
  • the booster 23 comprises a transistor Ql and passive elements.
  • the booster 23 amplifies and outputs the broadcasting channel signal input from the rejection filter 22 such that the broadcasting channel signal can be tuned in a superior reception state.
  • the broadcasting channel signal is input through an antenna ANT, and then input to the citizen band filter 21 through a loop through 20.
  • the citizen band filter 21 removes a signal having a frequency band in the range of 26MHz to 30MHz.
  • the broadcasting channel signal is input to the booster 23 through the rejection filter 22.
  • the booster 23 amplifies the input broadcasting channel signal and outputs the amplified broadcasting channel signal to the tuner.
  • the rejection filer 22 attenuates a signal input through the antenna if the signal has a frequency band outside a broadcasting channel band. For example, if a GSM signal (948MHz), which has the intensity in the range of OdBm to +1OdBm, and employs a frequency band exceeding 900MHz as a central frequency, is received, the intensity of the GSM signal is attenuated to down as much as 3OdB to 4OdB through the rejection filter 22. As described above, the rejection filter 22 previously filters a signal having a great intensity except for a broadcasting channel signal. Accordingly, a signal excluding a broadcasting channel signal is not input to the booster 23, thereby preventing the broadcasting channel signal from being affected by an external signal.
  • the above booster circuit is adaptable for a mobile communication terminal.
  • the mobile communication terminal comprises a tuner (e.g., a ground wave tuner) for selecting a broadcasting channel signal.
  • a tuner e.g., a ground wave tuner
  • the ground wave tuner may be realized through an OFDM scheme
  • the mobile communication terminal may be realized through a GSM scheme.
  • example embodiment means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention.
  • the appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with any embodiment, it is submitted that it is within the purview of one skilled in the art to effect such feature, structure, or characteristic in connection with other ones of the embodiments.
  • the intensity of an undesired signal input in an OFDM tuner is weakened, thereby preventing frequency interference from occurring.
  • an undesired signal is excluded when a broadcast channel signal is received, thereby preventing an OSC killing phenomenon of a tuner.

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Power Engineering (AREA)
  • Multimedia (AREA)
  • Input Circuits Of Receivers And Coupling Of Receivers And Audio Equipment (AREA)

Abstract

A booster circuit comprises a rejection filter for filtering a signal, which has a frequency band higher than a preset frequency band, among input signals, and a booster for receiving and amplifying a signal output from the rejection filter.

Description

Description
BOOSTER CIRCUIT
Technical Field
[1] The embodiment relates to a booster circuit.
Background Art
[2] A mobile communication terminal has employed a function of receiving ground wave broadcasting, and an orthogonal frequency division multiplexing (OFDM) scheme, which is a European scheme, has been employed as one of ground wave broadcasting schemes.
[3] When a mobile communication terminal employing a global system for mobile communication (GSM) receives a broadcast by using an OFDM ground wave tuner, frequency interference may occur. For example, when a use frequency band of the GSM mobile communication terminal is close to a frequency band of the OFDM ground wave tuner, which is receiving the broadcast, frequency interference may occur.
[4] This phenomenon may occur when the intensity of a GSM signal input through an antenna and a citizen band filter is greater than the intensity of an oscillating frequency of an oscillator of the ground wave tuner. In other words, the oscillation of the ground wave tuner may be affected by the input GSM signal, so that an OSC killing phenomenon, in which the oscillator is not oscillated, occurs.
[5] For example, if a GSM signal (948MHz) employing a central frequency of 900MHz is input while a desired broadcasting channel signal having a frequency of 474 MHz is being received in an OFDM ground wave broadcasting band within the range of 50MHz to 858MHz, interference occurs between two signals.
[6] In addition, the intensity of a GSM signal (OdBm to +1OdBm) is much greater than the intensity of a broadcasting channel signal (-8OdBm to -25dBm). If a signal having a strong intensity like the GSM signal is input to a booster, the signal is coupled with the broadcasting signal in the booster to make another interference signal.
[7] Accordingly, the booster amplifies the strong GSM signal, so that a stronger GSM signal causes an OSC killing phenomenon of killing an oscillator of a tuner, and a mutual interference exerts a fatal influence on a reception performance. Disclosure of Invention Technical Problem
[8] The embodiment provides a booster circuit capable of reducing frequency in- terference by weakening the intensity of an unnecessary signal input to an OFDM tuner. [9] The embodiment provides a booster circuit capable of preventing an OSC killing phenomenon of a tuner by excluding an unnecessary broadcasting channel signal when a broadcasting channel signal is received.
Technical Solution [10] According to the embodiment, a booster circuit comprises a rejection filter for filtering a signal, which has a frequency band higher than a preset frequency band, among input signals, and a booster for receiving and amplifying a signal output from the rejection filter. [11] According to the embodiment, a mobile communication terminal comprises a booster circuit, which comprises a rejection filter filtering a signal, which has a frequency band higher than a frequency band of a broadcasting channel signal, among input signals, and a booster amplifying a signal output from the rejection filter, and a tuner which receives a signal output from the booster circuit.
Advantageous Effects
[12] According to the embodiment, the intensity of an unnecessary signal input to an
OFDM tuner is weakened, thereby preventing frequency interference. [13] According to the embodiment, an unnecessary broadcasting signal is excluded when a broadcasting channel signal is received, thereby preventing an OSC killing phenomenon of a tuner.
Brief Description of the Drawings
[14] FIG. 1 is a block diagram showing a booster circuit according to the embodiment;
[15] FIG. 2 is a circuit diagram showing a booster circuit according to the embodiment; and [16] FIG. 3 is a graph showing the characteristic of a booster circuit according to the embodiment.
Mode for the Invention [17] Hereinafter, the embodiment will be described with reference to accompanying drawings.
[18] FIG. 1 is a block diagram showing a booster circuit according to the embodiment.
[19] As shown in FIG. 1, the booster circuit comprises a citizen band filter 11, a rejection filter 12, and a booster 13. [20] The citizen band filter 11 removes a citizen band signal from an input signal. The input signal may be a broadcasting channel signal input through an antenna.
[21] The rejection filter 12 attenuates a signal, which is out of a desired frequency band, in signals having passed through the citizen band filter 11. For example, the rejection filter 12 may be realized to attenuate a signal, which has a frequency band excluding a frequency band for a broadcasting signal, in broadcasting channel signals in which a citizen band signal is removed. The attenuated signal may have a frequency band greater than the frequency band of the broadcasting channel signal.
[22] The booster 13 amplifies a signal input thereto from the rejection filter 12. For example, the booster 13 may receive a broadcasting channel signal output from the rejection filter 12 to amplify the broadcasting channel signal.
[23] In the booster circuit according to the embodiment, a signal having an unnecessary frequency band is attenuated in the rejection filter 12, thereby inputting only a signal having a desired frequency band to the booster 13. Accordingly, a received broadcasting channel signal may be prevented from being affected by an external signal.
[24] Such a booster circuit may be variously realized. For instance, a circuit shown in
FIG. 2 can be used as the booster circuit. FIG. 2 is a circuit diagram showing the booster circuit according to the embodiment, and FIG. 3 is a graph showing a characteristic of the booster circuit according to the embodiment.
[25] As shown in FIG. 2, the booster circuit according to the embodiment comprises a citizen band filter 21, a rejection filter 22, and a booster 23.
[26] The citizen band filter 21 comprises a capacitor C3 and an inductor L2. The citizen band filter 21 removes a signal having a citizen band in the range of 26MHz to 30MHz, which is not used, from broadcasting channel signals input from an antenna ANT.
[27] The rejection filter 22 comprises an inductor L3 and a capacitor C4. The rejection filter 22 may be realized to attenuate a signal except for the broadcasting channel signal input from the citizen band filter 21. For example, the rejection filter 22 may be realized to attenuate a signal having a frequency band exceeding 900MHz, which is greater than a frequency band of the broadcasting channel signal. The frequency band of the attenuated signal may be set by adjusting the capacity of the inductor L3 and the capacitor C4. For example, the rejection filter 22 can attenuate a GSM signal (948MHz) having the intensity within the range of OdBm to +1OdBm and employing a frequency band exceeding 900MHz as a central frequency.
[28] Meanwhile, FIG. 2 shows a case in which the rejection filter 22 comprises the inductor L3 and the capacitor C4. However, the rejection filter 22 may be variously constructed if necessary. The rejection filter 22 may comprise a single step filter as shown in FIG. 2 or a multi-step filter. In addition, the rejection filter 22 may have a structure in which a plurality of filters including an inductor and a capacitor are serially connected to each other.
[29] The booster 23 comprises a transistor Ql and passive elements. The booster 23 amplifies and outputs the broadcasting channel signal input from the rejection filter 22 such that the broadcasting channel signal can be tuned in a superior reception state.
[30] According to the embodiment, the broadcasting channel signal is input through an antenna ANT, and then input to the citizen band filter 21 through a loop through 20. The citizen band filter 21 removes a signal having a frequency band in the range of 26MHz to 30MHz. The broadcasting channel signal is input to the booster 23 through the rejection filter 22. The booster 23 amplifies the input broadcasting channel signal and outputs the amplified broadcasting channel signal to the tuner.
[31] In this case, the rejection filer 22 attenuates a signal input through the antenna if the signal has a frequency band outside a broadcasting channel band. For example, if a GSM signal (948MHz), which has the intensity in the range of OdBm to +1OdBm, and employs a frequency band exceeding 900MHz as a central frequency, is received, the intensity of the GSM signal is attenuated to down as much as 3OdB to 4OdB through the rejection filter 22. As described above, the rejection filter 22 previously filters a signal having a great intensity except for a broadcasting channel signal. Accordingly, a signal excluding a broadcasting channel signal is not input to the booster 23, thereby preventing the broadcasting channel signal from being affected by an external signal.
[32] As described above, according to the embodiment, if an undesired signal having a great intensity except to a broadcasting channel signal is input through an antenna in a ground wave tuner, the intensity of the signal is attenuated or excluded by the rejection filter before the signal is input to the booster. Accordingly, it is possible to prevent the undesired signal from interfering the broadcasting channel signal due to the amplification of the undesired signal or prevent an OSC killing phenomenon in which an oscillator of a tuner is not oscillated.
[33] The above booster circuit is adaptable for a mobile communication terminal. The mobile communication terminal comprises a tuner (e.g., a ground wave tuner) for selecting a broadcasting channel signal. For example, the ground wave tuner may be realized through an OFDM scheme, and the mobile communication terminal may be realized through a GSM scheme. [34] Any reference in this specification to "one embodiment", "an embodiment",
"example embodiment" etc., means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with any embodiment, it is submitted that it is within the purview of one skilled in the art to effect such feature, structure, or characteristic in connection with other ones of the embodiments.
[35] Although embodiments have been described with reference to a number of illustrative embodiments thereof, it should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the spirit and scope of the principles of this disclosure. More particularly, various variations and modifications are possible in the component parts and/or arrangements of the subject combination arrangement within the scope of the disclosure, the drawings and the appended claims. In addition to variations and modifications in the component parts and/or arrangements, alternative uses will also be apparent to those skilled in the art. Industrial Applicability
[36] According to the embodiment, the intensity of an undesired signal input in an OFDM tuner is weakened, thereby preventing frequency interference from occurring.
[37] According to the embodiment, an undesired signal is excluded when a broadcast channel signal is received, thereby preventing an OSC killing phenomenon of a tuner.

Claims

Claims
[ 1 ] A booster circuit comprising : a rejection filter for filtering a signal, which has a frequency band higher than a preset frequency band, among input signals; and a booster for receiving and amplifying a signal output from the rejection filter.
[2] The booster circuit as claimed in claim 1, wherein the rejection filter attenuates and outputs an intensity of an input signal if the input signal has a frequency band higher than the preset frequency band.
[3] The booster circuit as claimed in claim 1, wherein the rejection filter is provided at a front end portion of the booster.
[4] The booster circuit as claimed in claim 1, wherein the rejection filter comprises an inductor and a capacitor.
[5] The booster circuit as claimed in claim 4, wherein the inductor is connected to the capacitor in parallel.
[6] The booster circuit as claimed in claim 1, wherein the rejection filter comprises a structure in which a plurality of filters comprising an inductor and a capacitor are serially connected to each other.
[7] The booster circuit as claimed in claim 1, wherein the preset frequency band is a frequency band of a broadcasting channel signal.
[8] The booster circuit as claimed in claim 1, wherein the preset frequency band is within a range of 50MHz to 858MHz.
[9] The booster circuit as claimed in claim 1, comprising a citizen band filter which removes a citizen band signal from signals input through an antenna, and provides the removed signal to the rejection filter.
[10] A mobile communication terminal comprising: a booster circuit, which comprises a rejection filter filtering a signal, which has a frequency band higher than a frequency band of a broadcasting channel signal, among input signals, and a booster amplifying a signal output from the rejection filter; and a tuner which receives a signal output from the booster circuit.
[11] The mobile communication terminal as claimed in claim 10, wherein the tuner is an orthogonal frequency-division multiplexing ground wave tuner, and the mobile communication terminal is driven through a global system for mobile communication scheme.
[12] The mobile communication terminal as claimed in claim 10, wherein the rejection filter attenuates and outputs an intensity of an input signal if the input signal has a frequency band higher than the frequency band of the broadcasting channel signal.
[13] The mobile communication terminal as claimed in claim 10, wherein the rejection filter is provided at a front end portion of the booster.
[14] The mobile communication terminal as claimed in claim 10, wherein the rejection filter comprises an inductor and a capacitor.
[15] The mobile communication terminal as claimed in claim 14, wherein the inductor is connected to the capacitor in parallel.
[16] The mobile communication terminal as claimed in claim 10, wherein the rejection filter comprises a structure in which a plurality of filters comprising an inductor and a capacitor are serially connected to each other.
[17] The mobile communication terminal as claimed in claim 10, wherein the frequency band of the broadcasting channel signal is within a range of 50MHz to 858MHz.
[18] The mobile communication terminal as claimed in claim 10, comprising a citizen band filter which removes a citizen band signal from signals input through an antenna, and provides the removed signal to the rejection filter.
PCT/KR2007/004497 2006-09-22 2007-09-18 Booster circuit WO2008035893A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP07808287A EP2052537A4 (en) 2006-09-22 2007-09-18 Booster circuit

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
KR1020060092262A KR20080026968A (en) 2006-09-22 2006-09-22 Input circuit of ground wave tuner
KR10-2006-0092262 2006-09-22

Publications (1)

Publication Number Publication Date
WO2008035893A1 true WO2008035893A1 (en) 2008-03-27

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ID=39200689

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/KR2007/004497 WO2008035893A1 (en) 2006-09-22 2007-09-18 Booster circuit

Country Status (3)

Country Link
EP (1) EP2052537A4 (en)
KR (1) KR20080026968A (en)
WO (1) WO2008035893A1 (en)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5638141A (en) * 1994-04-29 1997-06-10 Samsung Electronics Co., Ltd. Broadcast signal receiver having a low-noise amplifier inserted before a tuner
US6594477B1 (en) * 1999-08-20 2003-07-15 Sharp Kabushiki Kaisha Electronic tuner
US20050190304A1 (en) * 2004-02-27 2005-09-01 Ryu Jong G. Radio frequency (RF) modulator with narrow bandpass filter

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3547292B2 (en) * 1997-06-17 2004-07-28 アルプス電気株式会社 Television signal receiving tuner
WO2002073794A2 (en) * 2001-03-09 2002-09-19 California Institute Of Technology Switchless multi-resonant, multi-band power amplifier
WO2003015301A1 (en) * 2001-08-10 2003-02-20 Hitachi Metals, Ltd. Bypass filter, multi-band antenna switch circuit, and layered module composite part and communication device using them
JP2005080109A (en) * 2003-09-02 2005-03-24 Murata Mfg Co Ltd High frequency switching circuit
JP2005323063A (en) * 2004-05-07 2005-11-17 Hitachi Metals Ltd Branching filter circuit

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5638141A (en) * 1994-04-29 1997-06-10 Samsung Electronics Co., Ltd. Broadcast signal receiver having a low-noise amplifier inserted before a tuner
US6594477B1 (en) * 1999-08-20 2003-07-15 Sharp Kabushiki Kaisha Electronic tuner
US20050190304A1 (en) * 2004-02-27 2005-09-01 Ryu Jong G. Radio frequency (RF) modulator with narrow bandpass filter

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP2052537A4 *

Also Published As

Publication number Publication date
EP2052537A4 (en) 2011-03-16
KR20080026968A (en) 2008-03-26
EP2052537A1 (en) 2009-04-29

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