KR100501182B1 - Broadband 2-Input Modulation Circuit - Google Patents
Broadband 2-Input Modulation Circuit Download PDFInfo
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- KR100501182B1 KR100501182B1 KR10-1998-0027253A KR19980027253A KR100501182B1 KR 100501182 B1 KR100501182 B1 KR 100501182B1 KR 19980027253 A KR19980027253 A KR 19980027253A KR 100501182 B1 KR100501182 B1 KR 100501182B1
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- modulation circuit
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- 230000005540 biological transmission Effects 0.000 claims abstract description 46
- 239000013078 crystal Substances 0.000 claims abstract description 19
- 239000003990 capacitor Substances 0.000 claims description 14
- 230000010355 oscillation Effects 0.000 description 7
- 238000010586 diagram Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000005236 sound signal Effects 0.000 description 1
Classifications
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03C—MODULATION
- H03C3/00—Angle modulation
- H03C3/02—Details
- H03C3/09—Modifications of modulator for regulating the mean frequency
- H03C3/0908—Modifications of modulator for regulating the mean frequency using a phase locked loop
- H03C3/0958—Modifications of modulator for regulating the mean frequency using a phase locked loop applying frequency modulation by varying the characteristics of the voltage controlled oscillator
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03L—AUTOMATIC CONTROL, STARTING, SYNCHRONISATION OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES
- H03L7/00—Automatic control of frequency or phase; Synchronisation
- H03L7/06—Automatic control of frequency or phase; Synchronisation using a reference signal applied to a frequency- or phase-locked loop
- H03L7/08—Details of the phase-locked loop
- H03L7/099—Details of the phase-locked loop concerning mainly the controlled oscillator of the loop
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03L—AUTOMATIC CONTROL, STARTING, SYNCHRONISATION OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES
- H03L7/00—Automatic control of frequency or phase; Synchronisation
- H03L7/06—Automatic control of frequency or phase; Synchronisation using a reference signal applied to a frequency- or phase-locked loop
- H03L7/16—Indirect frequency synthesis, i.e. generating a desired one of a number of predetermined frequencies using a frequency- or phase-locked loop
- H03L7/18—Indirect frequency synthesis, i.e. generating a desired one of a number of predetermined frequencies using a frequency- or phase-locked loop using a frequency divider or counter in the loop
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- Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
Abstract
본 발명은 무선전화기, 무선키보드등과 같은 무선통신기기내 고주파-유니트(RF-unit)에 적용되며, 이 고주파-유니트(RF-unit)의 송신데이타(TX-D)가 무선키보드 등에 사용되는 주파수대역과 같이 낮은 송신주파수일 때 초래되는 송신데이타의 깨짐을 방지하도록하는 광대역용 2입력 변조회로(two input modulating circuit)에 관한 것으로, 본 발명에 따르면, 전압제어발진부와 수정발진부의 입력단 각각에 입력단 변조회로를 구현시켜, 낮은 송신주파수에서도 손신데이타가 깨지지 않고 안정적인 송신을 달성할 수 있도록 한 것이다.The present invention is applied to a high frequency unit (RF-unit) in a wireless communication device such as a wireless telephone, a wireless keyboard, etc., and the transmission data (TX-D) of the high frequency unit is used for a wireless keyboard or the like. The present invention relates to a wideband two input modulating circuit for preventing breakage of transmission data caused at a low transmission frequency, such as a frequency band. According to the present invention, an input terminal of a voltage controlled oscillator and a crystal oscillator By implementing the input modulation circuit, it is possible to achieve stable transmission without breaking the loss data even at low transmission frequency.
Description
본 발명은 무선전화기, 무선키보드등과 같은 무선통신기기내 고주파-유니트(RF-unit)에 적용되는 광대역용 2입력 변조회로(two input modulating circuit)에 관한 것으로, 특히 고주파-유니트(RF-unit)의 송신데이타(TX-D)가 무선키보드 등에 사용되는 주파수대역과 같이 낮은 송신주파수일 때 초래되는 송신데이타의 손상을 방지하도록하는 광대역용 2입력 변조회로에 관한 것이다.BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wideband two input modulating circuit applied to a high frequency unit in a wireless communication device such as a wireless telephone or a wireless keyboard. Particularly, the present invention relates to a high frequency unit. The present invention relates to a wide-band two-input modulation circuit for preventing damage to transmission data caused when the transmission data TX-D is a low transmission frequency such as a frequency band used for a wireless keyboard.
일반적으로, 무선통신기기의 이동단말기에는 고주파신호를 송신하기 위한 송신블럭과 고주파신호를 수신하기 위한 수신블럭을 각각 포함하는 고주파-유니트(RF-unit)가 내장되어 있다. 그리고 상기 고주파-유니트의 송신블럭에는 송신할 신호나 데이타에 의해 특정 주파수로 발진된 고주파를 변조시켜 이를 다시 증폭시킨후 안테나를 통해서 무선송출한다. 그런데, 상기 고주파-유니트제품에서 오디오(Audio)신호가 저주파에서 왜곡되는 문제점이 대두되었다.In general, a mobile terminal of a wireless communication device includes a radio frequency unit (RF-unit) including a transmission block for transmitting a high frequency signal and a reception block for receiving a high frequency signal. The high frequency-unit transmission block modulates a high frequency oscillated at a specific frequency by a signal or data to be transmitted, amplifies it again, and transmits the radio frequency through an antenna. However, a problem arises in that an audio signal is distorted at a low frequency in the high frequency unit product.
따라서, 종래의 변조회로에서는, 도 1에 도시한 바와같이, 송신데이타(TX-D)를 전압제어발진부(11)와 수정발진기(14) 각각으로 입력시키는 2입력 변조회로(two input modulating circuit)를 채택하고 있다.Therefore, in the conventional modulation circuit, as shown in Fig. 1, a two input modulating circuit for inputting the transmission data TX-D to the voltage controlled oscillator 11 and the crystal oscillator 14, respectively. Is adopted.
이와같은 종래 2입력 고주파 변조회로는 송신데이타(TX-D)는 전압제어발진부(11)와 수정발진부(14)로 각각 제공되며, 전압제어발진기(11)와 수정발진기(14)는 송신데이타에 의해 각 발진주파수가 변조되어 출력되는데, 이전에 위상동기루프(13)는 전압제어발진부(11)의 출력주파수를 소정분주값으로 분주한 분주주파수와 수정발진부(14)의 출력주파수간 위상차를 검출한후 전압제어발진부(11)로 위상차에 해당하는 전압을 출력하여 전압제어발진부(11)가 안정된 변조동작을 수행할 수 있도록 위상동기를 행한다.In the conventional two-input high frequency modulation circuit, the transmission data TX-D is provided to the voltage controlled oscillator 11 and the crystal oscillator 14, respectively, and the voltage controlled oscillator 11 and the crystal oscillator 14 are transmitted to the transmission data. Each oscillation frequency is modulated and output. The phase synchronization loop 13 detects a phase difference between the frequency division frequency obtained by dividing the output frequency of the voltage controlled oscillation unit 11 into a predetermined division value and the output frequency of the crystal oscillation unit 14. After that, a voltage corresponding to the phase difference is output to the voltage controlled oscillator 11 so that the voltage controlled oscillator 11 performs a stable modulation operation.
이와같은 종래의 2입력 고주파 변조회로는 송신주파수가 200Mhz 이상으로 높을 경우에는 송신데이타가 깨지지 않지만, 예를들어 무선키보드에서 사용하는 무선주파수(대략, 50Mhz)등과 같이, 송신주파수가 100Mhz 이하로 낮을 경우에는 위상동기루프의 주파수분주값이 작고 전압제어발진부와 수정발진부의 가변폭이 좁은 관계로, 위상동기루프가 최적의 위상동기를 수행하지 못하여 송신데이타가 깨지는 문제점이 있었던 것이다. In the conventional two-input high frequency modulation circuit, the transmission data is not broken when the transmission frequency is higher than 200Mhz, but the transmission frequency is lower than 100Mhz, for example, the radio frequency (approximately 50Mhz) used in the wireless keyboard. In this case, since the frequency division value of the phase synchronization loop is small and the variable widths of the voltage controlled oscillator and the crystal oscillator are narrow, there is a problem in that the transmission data is broken because the phase synchronization loop does not perform optimal phase synchronization.
본 발명은 상기한 문제점을 해결하기 위해 안출한 것으로, 따라서, 본 발명의 목적은 고주파-유니트(RF-unit)의 송신데이타(TX-D)가 무선키보드 등에 사용되는 주파수대역과 같이 낮은 송신주파수일 때 초래되는 송신데이타의 손상을 방지하도록하는 광대역용 2입력 변조회로를 제공하는데 있다.SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and therefore, an object of the present invention is to provide a low transmission frequency such as a frequency band in which TX-D transmission data of a high frequency unit is used in a wireless keyboard or the like. To provide a wideband two-input modulation circuit for preventing damage to the transmission data caused when.
상기한 본 발명의 목적을 달성하기 위한 기술적인 수단으로써, 본 발명의 회로는 송신데이타에 의해 송신주파수를 변조하는 전압제어발진부와, 상기 송신데이타에 의해 기준주파수를 변조하는 수정발진부와, 상기 변조된 송신주파수를 소정주파수로 분주하고 이 분주된 주파수와 기준주파수간 위상차를 비교한후 이 위상차에 해당하는 전압을 전압제어발진기로 제공하는 위상동기루프를 포함하는 2입력 변조회로에 있어서, 상기 송신데이타입력단과 수정발진부사이의 신호라인중 제1 접속점과 제2접속점을 접속한 저항과, 상기 제1 접속점과 제3 접속점을 접속한 저항과, 상기 제2 접속점과 제3 접속점을 접속한 커패시터와, 상기 제3 접속점에 캐소드단을 접속하고 그 애노드단을 접지시킨 제1 바랙터 다이오드와, 상기 제2 접속점에 캐소드단을 접속하고 그 애노드단을 접지시킨 제2 바랙터 다이오드와, 상기 제2 접속점과 상기 수정발진부를 접속한 커패시터로 구성한 제2 입력단 변조회로; 를 구비함을 특징으로 한다.As a technical means for achieving the above object of the present invention, the circuit of the present invention includes a voltage controlled oscillator for modulating a transmission frequency by transmission data, a crystal oscillator for modulating a reference frequency by the transmission data, and the modulation A two-input modulation circuit comprising: a phase-locked loop which divides a given transmission frequency into a predetermined frequency, compares a phase difference between the divided frequency and a reference frequency, and provides a voltage corresponding to the phase difference to a voltage controlled oscillator. A resistor connecting the first connection point and the second connection point of the signal line between the data input terminal and the crystal oscillator, a resistor connecting the first connection point and the third connection point, a capacitor connecting the second connection point and the third connection point; A first varactor diode having a cathode end connected to the third connection point and grounded at the anode end thereof, and a cathode end connected to the second connection point; And that the anode terminal grounded and a second varactor diode, a second input the modulation circuit is configured with a capacitor connected to the oscillation unit and the modified second connection point; Characterized in having a.
이하, 본 발명에 따른 광대역용 2입력 변조회로에 대해서 첨부한 도면을 참조하여 상세하게 설명한다. 본 발명에 참조된 도면에서 실질적으로 동일한 구성과 기능을 가진 구성요소들은 동일한 부호를 사용할 것이다.Hereinafter, a wideband two-input modulation circuit according to the present invention will be described in detail with reference to the accompanying drawings. In the drawings referred to in the present invention, components having substantially the same configuration and function will use the same reference numerals.
도 2는 본 발명에 따른 2입력 변조회로에 대한 내부회로도로서, 도 2를 참조하면, 본 발명에 따른 광대역용 2입력 변조회로는 송신데이타(TX-D)에 의해 송신주파수를 변조하는 전압제어발진부(11)와, 상기 송신데이타(TX-D)에 의해 기준주파수를 변조하는 수정발진부(14)와, 상기 변조된 송신주파수를 소정주파수로 분주하고 이 분주된 주파수와 기준주파수간 위상차를 비교한후 이 위상차에 해당하는 전압을 전압제어발진기로 제공하는 위상동기루프(13)를 포함한다.FIG. 2 is an internal circuit diagram of a two-input modulation circuit according to the present invention. Referring to FIG. 2, the broadband two-input modulation circuit according to the present invention modulates a transmission frequency by transmission data TX-D. An oscillator 11, a crystal oscillator 14 modulating a reference frequency by the transmission data TX-D, and the modulated transmission frequency are divided by a predetermined frequency, and the phase difference between the divided frequency and the reference frequency is compared. Then, the phase synchronization loop 13 provides a voltage corresponding to the phase difference to the voltage controlled oscillator.
그리고, 상기 광대역용 2입력 변조회로는 상기 송신데이타(TX-D)입력단과 수정발진부(14)사이의 신호라인중 제1 접속점(BP1)과 제2접속점(BP2)을 접속한 저항(R3)과, 상기 제1 접속점(BP1)과 제3 접속점(BP3)을 접속한 저항(R4)과, 상기 제2 접속점(BP2)과 제3 접속점(BP3)을 접속한 커패시터(C3)와, 상기 제3 접속점(BP3)에 캐소드단을 접속하고 그 애노드단을 접지시킨 제1 바랙터 다이오드(VD1)와, 상기 제2 접속점(BP2)에 캐소드단을 접속하고 그 애노드단을 접지시킨 제2 바랙터 다이오드(VD2)와, 상기 제2 접속점(BP2)과 상기 수정발진부(14)를 접속한 커패시터(C4)로 구성한 제2 입력단 변조회로(10)를 더 포함한다.The broadband two-input modulation circuit includes a resistor R3 connecting a first connection point BP1 and a second connection point BP2 of a signal line between the transmission data TX-D input terminal and the crystal oscillator 14. And a resistor R4 connecting the first connection point BP1 and the third connection point BP3, a capacitor C3 connecting the second connection point BP2 and the third connection point BP3, and the first connection point. A first varactor diode VD1 having a cathode end connected to the third connection point BP3 and the anode end thereof grounded, and a second varactor having a cathode end connected to the second connection point BP2 and grounded at the anode end thereof. And a second input stage modulation circuit 10 composed of a diode VD2 and a capacitor C4 connecting the second connection point BP2 and the crystal oscillator 14.
또한, 상기 광대역용 2입력 변조회로는 전압제어발진부(11) 전단에 제1 입력단 변조회로(8)를 더 포함하는데, 이 제1 입력단 변조회로(8)는 상기 송신데이타(TX-D)입력단과 전압제어발진부(11)사이의 신호라인상에 직렬로 접속한 가변저항(VR1) 및 두 개의 커패시터(C1,C2)와, 상기 두 커패시터(C1,C2) 접속점에 캐소드단을 접속함과 동시에 그 애노드단을 접지시킨 바랙터 다이오드(VD0)와, 상기 바랙터 다이오드(VD0)의 캐소드단에 저항(R2)을 통해서 튜닝전압을 제공하는 전압단(+VCC) 및 상기 바랙터 다이오드(VD0)의 캐소드단과 커패시터(C1)사이에 접속한 저항(R1)으로 구성한다.In addition, the broadband two-input modulation circuit further includes a first input stage modulation circuit 8 in front of the voltage controlled oscillator 11, the first input stage modulation circuit 8 includes the transmission data (TX-D) input stage. The cathodes are connected to the variable resistor VR1 and two capacitors C1 and C2 connected in series on the signal line between the overvoltage control oscillator 11 and the connection points of the two capacitors C1 and C2. The varactor diode VD0 having its anode terminal grounded, the voltage terminal + VCC providing the tuning voltage to the cathode terminal of the varactor diode VD0 through a resistor R2, and the varactor diode VD0. The resistor R1 is connected between the cathode end of the capacitor and the capacitor C1.
이와같이 구성된 본 발명에 따른 동작을 첨부도면에 의거하여 하기에 상세히 설명한다. Operation according to the present invention configured as described above will be described in detail below based on the accompanying drawings.
도 2를 참조하여 본 발명에 따른 광대역용 2입력 변조회로에 대한 동작을 설명하면, 입력단을 통한 송신데이타(TX-D)는 분기되어 제1 입력단 변조회로(8)와 제2 입력단 변조회로(10)로 각각 입력된다.Referring to FIG. 2, the operation of the broadband two-input modulation circuit according to the present invention will be described. The transmission data TX-D through the input stage is branched to form a first input stage modulation circuit 8 and a second input stage modulation circuit ( 10) respectively.
먼저, 제1 입력단 변조회로(8)는 전압단(+VCC)를 통해 공급되는 튜닝전압에 의해서 바랙터 다이오드(D1)의 커패시턴스가 결정되며, 이 제1 입력단 변조회로(8)의 커패시턴스가 전압제어발진부(11)의 커패시턴스와 함께 상기 전압제어발진부(11)에서의 발진주파수를 결정한다.First, the capacitance of the varactor diode D1 is determined by the tuning voltage supplied through the voltage terminal (+ VCC) in the first input stage modulation circuit 8, and the capacitance of the first input stage modulation circuit 8 is a voltage. The oscillation frequency at the voltage controlled oscillator 11 is determined together with the capacitance of the controlled oscillator 11.
이에따라, 입력되는 송신데이타(TX-D)는 제1 입력단 변조회로(8)를 통한후 전압제어발진부(11)에 입력되고, 이 전압제어발진부(11)에서 송신데이타(TX-D)에 의해서 발진주파수가 변조되어 출력된다.Accordingly, the input transmission data TX-D is inputted to the voltage controlled oscillator 11 through the first input stage modulation circuit 8, and is transmitted by the voltage controlled oscillator 11 by the transmitted data TX-D. The oscillation frequency is modulated and output.
또한, 제2 입력단 변조회로(10)에서는 입력되는 송신데이타(TX-D)에 해당하는 신호크기에 따라 커패시턴스가 가변되는데, 이는 상기 제2 입력단 변조회로(10)에 입력되는 송신데이타(TX-D)에 해당하는 신호는 제1 및 제2 바랙터 다이오드(VD1,VD2)의 양단에 인가됨에 따라 제1 및 제2 바랙터 다이오드(VD1,VD2)의 커패시턴스가 입력된 신호크기에 따라 가변된다. In addition, in the second input stage modulation circuit 10, the capacitance varies according to the signal size corresponding to the transmission data TX-D input, which is the transmission data TX- inputted to the second input stage modulation circuit 10. As the signal corresponding to D) is applied to both ends of the first and second varactor diodes VD1 and VD2, the capacitances of the first and second varactor diodes VD1 and VD2 vary according to the input signal size. .
이와같이, 제2 입력단 변조회로(10)에 의해서 입력되는 신호에 따라 커패시턴스가 가변되고, 이 커패시턴스의 가변량이 후단의 수정발진부(14)의 커패시턴스에 영향하게 됨에 따라, 상기 수정발진부(14)에서는 제2 입력단 변조회로(10)에 의해서 종래보다 대략 2배 이상의 가변량을 가지므로, 송신주파수가 낮은 고주파신호이더라도 상기 수정발진부(14)에서의 가변량이 크므로 이 송신주파수를 커버할 수 있는 기준주파수를 수정발진부(14)에서 제공하게 된다.In this way, the capacitance is varied according to the signal input by the second input stage modulation circuit 10, and the variable amount of capacitance affects the capacitance of the crystal oscillator 14 at the rear stage, so that the crystal oscillator 14 has Since the two input stage modulation circuit 10 has a variable amount of about twice or more than the conventional one, even if a high frequency signal having a low transmission frequency has a large variable amount in the crystal oscillator 14, the reference frequency can cover this transmission frequency. Is provided by the crystal oscillator 14.
따라서, 입력되는 상기 수정발진부(14)의 변조를 안정하게 거는 것이 가능하게 된다. 이에따라 송신데이타가 깨지는등의 데이타 손상을 방지할 수 있는 것이다.Therefore, it becomes possible to stably modulate the modulation oscillator 14 input. As a result, data corruption, such as broken transmission data, can be prevented.
상술한 바와같은 본 발명에 따르면, 고주파-유니트(RF-unit)의 송신데이타(TX-D)가 무선키보드 등에 사용되는 주파수대역과 같이 낮은 송신주파수일 때 초래되는 송신데이타의 깨짐을 방지하도록하는 특별한 효과가 있다.According to the present invention as described above, the transmission data (TX-D) of the high frequency unit (RF-unit) to prevent the breakage of the transmission data caused when the low transmission frequency, such as the frequency band used for wireless keyboards, etc. It has a special effect.
이상의 설명은 본 발명의 일실시예에 대한 설명에 불과하며, 본 발명은 그 구성의 범위내에서 다양한 변경 및 개조가 가능한다.The above description is only a description of one embodiment of the present invention, the present invention is capable of various changes and modifications within the scope of the configuration.
도 1은 종래의 2입력 변조회로에 대한 내부회로도이다.1 is an internal circuit diagram of a conventional two-input modulation circuit.
도 2는 본 발명에 따른 2입력 변조회로에 대한 내부회로도이다.2 is an internal circuit diagram of a two input modulation circuit according to the present invention.
* 도면의 주요부분에 대한 부호의 설명 *Explanation of symbols on main parts of drawing
8 : 제1 입력단 변조회로 10 : 제2 입력단 변조회로8: first input stage modulation circuit 10: second input stage modulation circuit
11 : 전압제어발진부 12 : 증폭부11: voltage controlled oscillator 12: amplifier
13 : 위상동기루프 14 : 수정발진부13 phase synchronization loop 14 crystal oscillation unit
VD0∼VD2 : 바랙터 다이오드 VR1 : 가변저항VD0 to VD2: Varactor diode VR1: Variable resistor
R1∼R4 : 저항 C1∼C4 : 커패시터R1 to R4: Resistor C1 to C4: Capacitor
Claims (2)
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR10-1998-0027253A KR100501182B1 (en) | 1998-07-07 | 1998-07-07 | Broadband 2-Input Modulation Circuit |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR10-1998-0027253A KR100501182B1 (en) | 1998-07-07 | 1998-07-07 | Broadband 2-Input Modulation Circuit |
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| Publication Number | Publication Date |
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| KR20000007764A KR20000007764A (en) | 2000-02-07 |
| KR100501182B1 true KR100501182B1 (en) | 2005-09-26 |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH03214908A (en) * | 1990-01-19 | 1991-09-20 | Matsushita Electric Ind Co Ltd | Fm modulator |
| KR920022643A (en) * | 1991-05-23 | 1992-12-19 | 정용문 | FM modulator compensates for channel-specific modulation characteristics |
| JPH07183923A (en) * | 1993-09-28 | 1995-07-21 | Plessey Semiconductors Ltd | Modulator |
| JPH09130146A (en) * | 1995-10-31 | 1997-05-16 | Kyocera Corp | Low frequency data modulation circuit for fm radio unit |
-
1998
- 1998-07-07 KR KR10-1998-0027253A patent/KR100501182B1/en not_active IP Right Cessation
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH03214908A (en) * | 1990-01-19 | 1991-09-20 | Matsushita Electric Ind Co Ltd | Fm modulator |
| KR920022643A (en) * | 1991-05-23 | 1992-12-19 | 정용문 | FM modulator compensates for channel-specific modulation characteristics |
| JPH07183923A (en) * | 1993-09-28 | 1995-07-21 | Plessey Semiconductors Ltd | Modulator |
| JPH09130146A (en) * | 1995-10-31 | 1997-05-16 | Kyocera Corp | Low frequency data modulation circuit for fm radio unit |
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|---|---|
| KR20000007764A (en) | 2000-02-07 |
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