KR0168957B1 - Transceiver having a voltage controlled oscillator commonly used for both transmitting part and receiving part - Google Patents
Transceiver having a voltage controlled oscillator commonly used for both transmitting part and receiving part Download PDFInfo
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- KR0168957B1 KR0168957B1 KR1019950042998A KR19950042998A KR0168957B1 KR 0168957 B1 KR0168957 B1 KR 0168957B1 KR 1019950042998 A KR1019950042998 A KR 1019950042998A KR 19950042998 A KR19950042998 A KR 19950042998A KR 0168957 B1 KR0168957 B1 KR 0168957B1
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- 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
- H04B1/38—Transceivers, i.e. devices in which transmitter and receiver form a structural unit and in which at least one part is used for functions of transmitting and receiving
- H04B1/40—Circuits
- H04B1/44—Transmit/receive switching
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- 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
- H04B1/38—Transceivers, i.e. devices in which transmitter and receiver form a structural unit and in which at least one part is used for functions of transmitting and receiving
- H04B1/40—Circuits
- H04B1/403—Circuits using the same oscillator for generating both the transmitter frequency and the receiver local oscillator frequency
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- Computer Networks & Wireless Communication (AREA)
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- Inductance-Capacitance Distribution Constants And Capacitance-Resistance Oscillators (AREA)
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Abstract
본 발명은 휴대폰, 무선전화기 등에 구비되며, 스위칭 제어신호에 따라서 송신용 발진신호와 수신용 발진신호를 출력하는 송수신겸용 전압제어발진기를 구비하여 구성이 간소화된 송수신기에 관한 것으로, 상기 송수신겸용 전압제어발진기는 입력되는 튜닝전압에 의하여 공진하는 공진회로와, 상기 공진회로에서 동조된 주파수신호를 증폭하여 출력하는 증폭회로와, 상기 증폭회로와 공진회로 사이에 구비되어 스위칭 동작에 따라 인덕턴스 값을 변화시킴으로써 공진회로에서 동조되는 주파수를 변화시키는 발진주파수 선택부를 구비한다.The present invention relates to a transceiver provided in a cellular phone, a wireless telephone, etc. and having a simplified transmission / reception voltage controlled oscillator for outputting a transmission oscillation signal and a reception oscillation signal according to a switching control signal. The oscillator is provided between a resonant circuit resonating by an input tuning voltage, an amplifying circuit for amplifying and outputting a frequency signal tuned by the resonant circuit, and being provided between the amplifying circuit and the resonant circuit to change an inductance value according to a switching operation. An oscillation frequency selector for varying the frequency tuned in the resonant circuit is provided.
Description
제1도는 종래의 송수신기의 구성을 보여주는 블록도이고,1 is a block diagram showing the configuration of a conventional transceiver,
제2도는 본 발명에 의한 송수신기의 구성을 보여주는 블록도이고,2 is a block diagram showing the configuration of a transceiver according to the present invention;
제3도는 제2도의 전압제어발진기의 일 실시예를 도시한 회로도이다.FIG. 3 is a circuit diagram showing an embodiment of the voltage controlled oscillator of FIG.
* 도면의 주요부분에 대한 부호의 설명* Explanation of symbols for main parts of the drawings
21,24,28 : 대역통과필터21,24,28: bandpass filter
22 : 저잡음증폭기(LAN; Low Noise Amplifier)22: Low Noise Amplifier (LAN)
23,30 : 믹서 25 : 복조기23,30 Mixer 25 Demodulator
26 : 전압제어발진기(VCO) 27 : 위상동기루프(PLL)26: voltage controlled oscillator (VCO) 27: phase locked loop (PLL)
29 : 고전력증폭기 31 : 변조기29 high power amplifier 31 modulator
본 발명은 휴대폰, 무선전화기 등에 구비되는 송수신기에 관한 것으로, 특히 스위칭제어신호에 따라서 공진회로의 인덕턴스를 변화시켜 송신용 발진신호 및 수신용 발진신호를 출력하는 송수신겸용 전압제어발진기를 구비한 송수신기에 관한 것이다.BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transceiver provided in a cellular phone, a wireless telephone, and the like, and more particularly, to a transceiver having a voltage controlled oscillator for both transmitting and receiving oscillation signals by varying the inductance of the resonant circuit according to a switching control signal. It is about.
일반적으로, 휴대폰이나 무선전화기 등은 고주파신호를 이용하여 통신하는 장치로써, 쌍방향 통신을 위하여 고주파신호로 변환된 음성신호를 송신 또는 수신할 수 있도록 송수신안테나에 연결되는 송신장치 및 수신장치를 구비하고 있다. 이러한 송수신장치에서, 송신주파수와 수신주파수는 대부분 약 45MHz의 차이를 두고 설정된다. 예를 들어, 휴대폰의 송신고주파신호가 959.5MHz 대역을 사용하면, 수신고주파신호는 914.5MHz 대역을 사용한다.In general, a mobile phone or a wireless telephone is a device for communicating using a high frequency signal, and includes a transmitting device and a receiving device connected to a transmitting and receiving antenna to transmit or receive a voice signal converted into a high frequency signal for bidirectional communication. have. In such a transceiver, the transmission frequency and the reception frequency are mostly set at a difference of about 45 MHz. For example, when the transmission high frequency signal of the cellular phone uses the 959.5 MHz band, the reception high frequency signal uses the 914.5 MHz band.
제1도는 종래의 송수신기의 구성을 보여주는 블록도로서, 수신기는 수신신호대역에서 통과특성을 갖는 대역통과필터(11)와, 상기 대역통과필터(11)로부터 출력된 신호를 저잡음 증폭하는 저잡음증폭기(12)와, 상기 저잡음증폭기(12)로부터 출력된 신호와 발진회로로부터 출력되는 신호를 혼합하는 믹서(13)와, 상기 믹서(13)에 발진신호를 출력하는 전압제어발진기(16)와, 상기 믹서(13)로부터 출력되는 신호의 대역외 신호를 저지하는 대역통과필터(14)와, 상기 대역통과필터(14)로부터 출력된 신호를 FM 복조하는 복조기(15)를 구비하고, 송신기는 원음성신호를 주파수 변조하는 변조기(22)와, 상기 변조기(22)로부터 출력된 신호를 발진신호와 혼합하여 고주파신호를 출력하는 믹서(21)와, 상기 믹서(21)에 발진신호를 출력하는 전압제어발진기(17)와, 상기 믹서(21)로부터 출력된 고주파신호를 고전력으로 증폭하는 고전력증폭기(20)와, 상기 고전력증폭기(20)로부터 출력되는 고주파신호에서 신호외 잡음을 저지하는 대역통과필터(19)를 구비하며, 상기 위상동기루프(18)는 드리프트에 의한 발진주파수의 뒤틀림을 보상하도록 동작한다.1 is a block diagram illustrating a conventional transceiver, wherein a receiver includes a band pass filter 11 having a pass characteristic in a reception signal band, and a low noise amplifier for low noise amplifying a signal output from the band pass filter 11. 12), a mixer 13 for mixing a signal output from the low noise amplifier 12 and a signal output from the oscillation circuit, a voltage controlled oscillator 16 for outputting an oscillation signal to the mixer 13, and And a band pass filter 14 for blocking out-of-band signals of the signal output from the mixer 13, and a demodulator 15 for FM demodulating the signal output from the band pass filter 14, wherein the transmitter has an original sound. A modulator 22 for frequency modulating a signal, a mixer 21 for mixing a signal output from the modulator 22 with an oscillation signal to output a high frequency signal, and voltage control for outputting an oscillation signal to the mixer 21. Oscillator 17 and the mixer 21 And a high power amplifier 20 for amplifying the high frequency signal outputted from the high power signal, and a band pass filter 19 for blocking out-of-signal noise in the high frequency signal output from the high power amplifier 20. 18) operates to compensate for distortion of the oscillation frequency due to drift.
이와 같이, 종래에는 송수신기에 송신신호의 주파수변환에 필요한 전압제어발진기와 수신신호의 주파수변환에 필요한 전압제어발진기를 각각 구비함으로써 구성이 커지고 복잡해지는 문제점이 있었다.As described above, there is a problem in that the transceiver is provided with a voltage-controlled oscillator for frequency conversion of a transmission signal and a voltage-controlled oscillator for frequency conversion of a received signal.
본 발명은 상기와 같은 문제점을 해결하기 위한 것으로, 그 목적은 스위칭신호에 따라서 송신용 발진신호와 수신용 발진신호를 출력하는 송수신겸용 전압제어발진기를 구비한 송수신기를 제공함에 있다.SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object thereof is to provide a transceiver having a voltage controlled oscillator for both transmitting and receiving oscillating signals for transmitting and receiving oscillating signals according to a switching signal.
상기와 같은 목적을 달성하기 위한 기술적인 수단으로써, 본 발명은 믹서를 포함하여 안테나로 수신된 고주파신호를 원음성신호로 복원하는 수신부와 믹서를 포함하여 음성신호를 고주파신호로 변조하여 송출하는 송신부를 포함하는 송수신기에 있어서,As a technical means for achieving the above object, the present invention includes a receiver for recovering the high frequency signal received by the antenna, including the mixer to the original audio signal and a transmitter for modulating and transmitting the voice signal into a high frequency signal including the mixer In the transceiver comprising a,
상기 송수신기가 다수의 콘덴서 및 코일과 함께 그 캐소드로 인가된 튜닝전압(VT)에 따라 동조주파수를 미세 조정하는 버렉터다이오드가 직병렬로 결합되어 소정 주파수에 동조하는 공진회로부와, 상기 공진회로부에 구비된 한 코일에 병렬로 연결된 스위칭 다이오드 및 콘덴서로 이루어져 상기 스위칭다이오드의 턴오프에 따라 상기 공진회로부의 동조주파수를 변화시키는 발진주파수 선택부와, 상기 공진회로부의 출력 측에 구비되어 상기 공진회로의 동조주파수대로 발진 증폭하여 송신부의 믹서 또는 수신부의 믹서로 출력하는 증폭회로로 이루어진 송수신겸용 전압제어발진기를 포함함을 특징으로 한다.A resonant circuit portion in which the transceiver is coupled to a plurality of capacitors and coils and a varactor diode for fine-tuning the tuning frequency according to the tuning voltage (VT) applied to the cathode thereof in series and parallel tuning to a predetermined frequency; An oscillation frequency selector configured to change a tuning frequency of the resonant circuit part according to a turn-off of the switching diode, comprising a switching diode and a capacitor connected in parallel to the provided coil, and provided at an output side of the resonant circuit part. It characterized in that it comprises a voltage-controlled oscillator for both transmission and reception comprising an amplifying circuit for oscillating and amplifying at a tuning frequency and outputting the mixer to the mixer of the transmitter or the mixer of the receiver.
이하 첨부한 도면을 참조하여 설명한다.It will be described below with reference to the accompanying drawings.
제2도는 본 발명에 의한 송수신기의 구성을 보여주는 블록도로서, 수신부는 안테나로 수신된 고주파신호 중 수신대역만을 통과시키는 대역통과필터(21)와, 상기 대역통과필터(21)를 통과한 고주파신호를 증폭하는 저잡음증폭기(22)와, 상기 저잡음증폭기(22)로부터 출력되는 고주파신호를 전압제어발진기(26)로부터 입력되는 발진신호와 혼합하여 중간주파신호로 변환하는 믹서(23)와, 상기 믹서(23)로부터 출력되는 중간주파신호대역만 통과시키는 대역통과필터(24)와, 상기 대역통과필터(24)를 통과한 신호를 FM복조하여 원 음성신호로 복원하는 복조기(25)와, 송신부는 원음성신호를 FM변조하는 변조기(31)와, 상기 변조기(31)로부터 출력되는 변조된 음성신호를 전압제어발진기(26)로부터 출력되는 송신대역의 발진신호와 혼합하여 고주파신호로 변환하는 믹서(30)와, 상기 믹서(30)로부터 출력되는 고주파신호를 고전력으로 증폭하는 고전력증폭기(29)와, 상기 고전력증폭기(29)와 안테나 사이에 구비되어 신호대역만 통과시키는 대역통과필터(28)를 구비한다. 그리고 상기 송신부 및 수신부에 공통되는 부분으로써, 송신/수신여부에 따라 입력되는 스위칭신호에 따라서 발진주파수를 변환하는 전압제어발진기(26)와, 상기 전압제어발진기(26)가 소정 범위 내에서 발진하도록 제어해주는 위상동기루프(27)를 구비한다.2 is a block diagram showing the configuration of a transceiver according to the present invention, in which a receiver passes a band pass filter 21 for passing only a reception band among high frequency signals received by an antenna, and a high frequency signal passed through the band pass filter 21. A low noise amplifier 22 for amplifying a, a mixer 23 for mixing a high frequency signal output from the low noise amplifier 22 with an oscillation signal input from a voltage controlled oscillator 26 and converting the signal into an intermediate frequency signal; A band pass filter 24 for passing only the intermediate frequency signal band outputted from (23), a demodulator 25 for FM demodulating the signal passing through the band pass filter 24 to restore the original audio signal, and a transmitting unit A modulator 31 for FM-modulating the original audio signal, and a mixer for mixing the modulated voice signal output from the modulator 31 with the oscillation signal of the transmission band output from the voltage controlled oscillator 26 and converting the signal into a high frequency signal. 30, a high power amplifier 29 for amplifying the high frequency signal output from the mixer 30 at high power, and a band pass filter 28 provided between the high power amplifier 29 and the antenna to pass only a signal band. It is provided. In addition, the voltage-controlled oscillator 26 and the voltage-controlled oscillator 26, which are common to the transmitter and the receiver, convert the oscillation frequency in accordance with a switching signal inputted according to transmission / reception or not, so that the voltage-controlled oscillator 26 oscillates within a predetermined range. It is provided with a phase synchronization loop 27 for controlling.
제3도는 본 발명에 의한 전압제어발진기의 또 다른 실시예로서, 버퍼용 트랜지스터와, 발진용 트랜지스터와, 다수의 저항 및 콘덴서로 이루어져 발진 및 증폭 동작하는 전기회로(31)와, 상기 증폭회로(31)의 입력 측에 연결되며 튜닝전압(VT)에 따라 캐패시턴스가 미세 조정되는 버렉터다이오드(D32) 및 다수의 콘덴서와 코일로 이루어져 소정 주파수(예를 들어, 수신대역주파수)에 동조하는 공진회로(22)와, 상기 공진회로(33)에 구비된 한 코일(L32)에 병렬로 연결되는 스위칭다이오드(D31)와 상기 스위칭다이오드(D31)와 접지 사이에 구비되는 콘덴서(C34)와 상기 스위칭다이오드(D31)와 콘덴서(C34)의 공통접점에 연결되어 스위칭신호가 입력되는 스위칭 신호입력단(34)으로 이루어진 주파수선택부(34)를 구비한다.3 is a further embodiment of the voltage controlled oscillator according to the present invention, comprising a buffer transistor, an oscillation transistor, an electric circuit 31 which oscillates and amplifies and consists of a plurality of resistors and capacitors; 31 is a resonant circuit connected to an input side of the inverter diode D32, the capacitance of which is fine-adjusted according to the tuning voltage VT, and a plurality of capacitors and coils to be tuned to a predetermined frequency (for example, a reception band frequency). And a switching diode D31 connected in parallel to one coil L32 provided in the resonant circuit 33 and a capacitor C34 and the switching diode provided between the switching diode D31 and ground. And a frequency selector 34, which is connected to the common contact of the capacitor D31 and the capacitor C34, and includes a switching signal input terminal 34 to which a switching signal is input.
본 발명의 작용 및 효과를 상세하게 설명한다.The operation and effects of the present invention will be described in detail.
제2도에서, 안테나로 수신된 수신대역의 고주파신호는 대역통과필터(21)와, 저잡음증폭기(22)에 의하여 잡음은 감쇄되고, 신호는 증폭되어 믹서(23)로 입력된다. 또한 전압제어발진기(26)는 제어회로(도시생략)로부터 입력되는 스위칭신호에 의하여 발진주파수선택부(33)가 동작하여 송신용 발진주파수를 발생시키거나, 수신용 발진주파수를 발생시킨다. 그 발진주파수선택부(33)의 동작은 아래에서 설명한다. 그리하여, 수신시에는 수신대역의 발진주파수를 상기 믹서(23)로 출력한다. 믹서(23)는 입력되는 두 신호(수신된 고주파신호와 발진신호)를 혼합하고, 상기 믹서(23)로부터 출력되는 수신된 고주파신호와 발진신호의 차신호는 대역통과필터(14)를 거쳐 복조기(15)로 입력되어 변조전의 원신호(음성신호)로 복원된다.In FIG. 2, the high frequency signal of the reception band received by the antenna is attenuated by the band pass filter 21 and the low noise amplifier 22, and the signal is amplified and input to the mixer 23. In FIG. Also, the voltage controlled oscillator 26 operates the oscillation frequency selector 33 by a switching signal input from a control circuit (not shown) to generate a transmission oscillation frequency or a reception oscillation frequency. The operation of the oscillation frequency selecting section 33 will be described below. Thus, upon reception, the oscillation frequency of the reception band is output to the mixer 23. The mixer 23 mixes two input signals (a received high frequency signal and an oscillation signal), and a difference signal between the received high frequency signal and the oscillation signal output from the mixer 23 passes through a band pass filter 14 to demodulator. Inputted to (15) is restored to the original signal (audio signal) before modulation.
그리고, 송신시에는 상기 전압제어발진기(26)는 송신대역으로 발진하여, 그 발진주파수를 믹서(30)로 출력한다. 그리하여 변조기(31)로부터 출력되는 변조된 음성신호는 믹서(30)에서 발진신호와 혼합되어 고주파신호로 변환된다. 믹서(30)로부터 출력된 신호는 고전력증폭기(29)에서 고전력으로 증폭되어 대역통과필터(28)를 거쳐 안테나를 통하여 송출된다.In transmission, the voltage controlled oscillator 26 oscillates in the transmission band and outputs the oscillation frequency to the mixer 30. Thus, the modulated voice signal output from the modulator 31 is mixed with the oscillation signal in the mixer 30 and converted into a high frequency signal. The signal output from the mixer 30 is amplified at high power in the high power amplifier 29 and transmitted through the antenna through the band pass filter 28.
제3도를 참조하여, 전압제어발진기(26)의 동작을 좀 더 상세하게 설명한다.Referring to FIG. 3, the operation of the voltage controlled oscillator 26 will be described in more detail.
즉, 스위칭신호입력단(34)로 입력되는 신호가 하이레벨 전압이면 스위칭다이오드(D31)는 도통 동작하여 코일(L32)에 병렬로 콘덴서(C34)가 연결된다. 그러면 캐패시턴스성분이 증가하고 발진주파수는 다운되어 낮은 주파수인 수신대역주파수로 발진하며, 입력되는 스위칭신호가 로우레벨전압이면 스위칭 다이오드(D31)는 차단되어, 콘덴서(C34)는 공진회로부(32)로부터 회로로부터 단락되게 된다. 그래서 캐패시턴스 성분이 낮아짐으로써 반진주파수가 높아져 상기 발진기는 송신대역의 주파수로 발진하게 된다.That is, when the signal input to the switching signal input terminal 34 is a high level voltage, the switching diode D31 is conducting and the capacitor C34 is connected in parallel to the coil L32. Then, the capacitance component is increased and the oscillation frequency is down to oscillate at a low frequency reception band frequency. When the input switching signal is a low level voltage, the switching diode D31 is cut off, and the capacitor C34 is discharged from the resonant circuit unit 32. Short circuit from the circuit. Thus, as the capacitance component is lowered, the oscillation frequency is increased, so that the oscillator oscillates at the frequency of the transmission band.
그리고, 상기에서, 튜닝전압(VT)에 따라 버렉터다이오드(D32)의 캐패시턴스성분이 가변되어, 상기 공진회로부(32)의 동조주파수가 미세 조정된다. 따라서, 이 튜닝전압(VT)을 조정함에 의해 전압제어발진기(26)의 발진주파수 틀어짐을 보상할 수 있게 된다.In addition, in the above, the capacitance component of the varactor diode D32 is varied according to the tuning voltage VT, and the tuning frequency of the resonance circuit part 32 is finely adjusted. Therefore, by adjusting this tuning voltage VT, the oscillation frequency shift of the voltage controlled oscillator 26 can be compensated.
이와 같이, 본 발명은 휴대폰 또는 무선전화기 등에 구비된 송수신기가 송신기의 믹서로 입력되는 발진신호와 수신기의 믹서로 입력되는 발진신호를 발생하는 송수신겸용 전압제어발진기를 구비함으로서, 송수신 시스템의 구성을 간소화시킬 수 있는 우수한 효과가 있는 것이다.As described above, the present invention simplifies the configuration of the transmission / reception system by providing a transmitter / receiver combined voltage controlled oscillator for generating an oscillation signal input to the mixer of the transmitter and an oscillation signal input to the mixer of the receiver. There is an excellent effect that can be made.
Claims (1)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1019950042998A KR0168957B1 (en) | 1995-11-22 | 1995-11-22 | Transceiver having a voltage controlled oscillator commonly used for both transmitting part and receiving part |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1019950042998A KR0168957B1 (en) | 1995-11-22 | 1995-11-22 | Transceiver having a voltage controlled oscillator commonly used for both transmitting part and receiving part |
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| Publication Number | Publication Date |
|---|---|
| KR970031408A KR970031408A (en) | 1997-06-26 |
| KR0168957B1 true KR0168957B1 (en) | 1999-02-01 |
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| Application Number | Title | Priority Date | Filing Date |
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| KR1019950042998A KR0168957B1 (en) | 1995-11-22 | 1995-11-22 | Transceiver having a voltage controlled oscillator commonly used for both transmitting part and receiving part |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100385588B1 (en) * | 2000-08-25 | 2003-05-27 | 삼성전기주식회사 | Voltage Control Oscillator for transmitting/receiving type |
| KR100765287B1 (en) * | 2006-01-23 | 2007-10-09 | 엘지전자 주식회사 | A radio frequency signal transceiver and a method thereof |
| EP1811678A3 (en) | 2006-01-23 | 2012-08-01 | LG Electronics Inc. | Radio frequency signal transmission/reception apparatus and radio frequency signal transmission/reception method |
| KR100765286B1 (en) * | 2006-01-23 | 2007-10-09 | 엘지전자 주식회사 | A radio frequency signal transceiver and a method thereof |
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1995
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