JPH04336715A - Frequency distributing circuit for modulator - Google Patents

Frequency distributing circuit for modulator

Info

Publication number
JPH04336715A
JPH04336715A JP3107901A JP10790191A JPH04336715A JP H04336715 A JPH04336715 A JP H04336715A JP 3107901 A JP3107901 A JP 3107901A JP 10790191 A JP10790191 A JP 10790191A JP H04336715 A JPH04336715 A JP H04336715A
Authority
JP
Japan
Prior art keywords
frequency
circuit
local
generator
transmission
Prior art date
Legal status (The legal status 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 status listed.)
Granted
Application number
JP3107901A
Other languages
Japanese (ja)
Other versions
JP2580888B2 (en
Inventor
Kazuya Oki
沖 和也
Hiroichi Ishida
博一 石田
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsubishi Electric Corp
Original Assignee
Mitsubishi Electric Corp
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 Mitsubishi Electric Corp filed Critical Mitsubishi Electric Corp
Priority to JP3107901A priority Critical patent/JP2580888B2/en
Publication of JPH04336715A publication Critical patent/JPH04336715A/en
Application granted granted Critical
Publication of JP2580888B2 publication Critical patent/JP2580888B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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Abstract

PURPOSE:To realize an inexpensive frequency distribution circuit with one frequency generator by frequency-dividing one local oscillation signal so as to generate a carrier and a local signal for a reception down-converter. CONSTITUTION:The circuit consists of a frequency generator 7 generating a local frequency being the multiple of N/(N+1) or N/(N-1) of a transmission frequency, a frequency dividing circuit 41 applying 1/N frequency division to the local frequency from the frequency generator 7, a modulation circuit 42 modulating the frequency division output from the frequency dividing circuit 41 by using a base band signal, an up-converter 5 and a frequency extracting circuit. That is, the local oscillation signal whose frequency is the multiple of N, N/(N+1) and the multiple of N/(N-1) of the transmission frequency is frequency-divided by the frequency dividing circuit 41 to generate a carrier having a phase difference of 90 deg.. Moreover, the local signal of the reception down-converter is generated based on the output of the frequency dividing circuit 41 or the local oscillation signal. In this case, one frequency generator 7 is sufficient for the purpose and an inexpensive and economical modulator is realized.

Description

【発明の詳細な説明】[Detailed description of the invention]

【0001】0001

【産業上の利用分野】本発明は1つの局部発振周波数を
分周して、送信周波数および受信用ローカル周波数を取
り出す変調装置の周波数分配回路に関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a frequency distribution circuit for a modulator that divides one local oscillation frequency to extract a transmission frequency and a reception local frequency.

【0002】0002

【従来の技術】図4は従来の変調装置の周波数分配回路
を示すブロック図である。図において、1は搬送波の4
倍の周波数を持つ第1局部発振信号を発生する周波数シ
ンセサイザによる第1の周波数発生器であり、電圧制御
型周波数可変発振器11、プリスケーラ12、分周回路
13、温度補償型水晶発振器14および位相比較回路1
5からなるフェーズロックドループにより構成される。 2は受信用の第2局部発振信号を発生する周波数シンセ
サイザによる第2の周波数発生器であり、電圧制御型周
波数可変発振器21、プリスケーラ22、分周回路23
、温度補償型水晶発振器24および位相比較回路25か
らなるフェーズロックドループにより構成される。3は
ベースバンド信号を発生する波形生成回路、4は第1の
周波数発生器1からの第1局部発振信号に基づく搬送波
を波形生成回路3からのベースバンド信号で直交変調す
る直交変調器であり、第1の周波数発生器1からの第1
局部発振信号を4分周して精度の良い90°の位相差を
持つ搬送波を発生する分周回路41、分周回路41から
の搬送波を波形生成回路3からのベースバンド信号によ
り変調する変調回路を構成するアナログスイッチ42お
よびアナログスイッチ42の出力信号から基本変調波を
抽出するローパスフィルタ43から構成される。5は直
交変調回路4から出力される基本変調波と第2の周波数
発生器からの第2局部発振信号とをミキシングして、所
定の送信周波数による送信変調波を生成するアップコン
バータである。6は受信復調部であり、受信周波数と第
2局部発振信号とをミキシングするダウンコンバータ6
2と、ダウンコンバータ62の出力を受けて復調を行な
う復調回路62から構成される。
2. Description of the Related Art FIG. 4 is a block diagram showing a frequency distribution circuit of a conventional modulation device. In the figure, 1 is the carrier wave 4
This is a first frequency generator using a frequency synthesizer that generates a first local oscillation signal with twice the frequency, and includes a voltage-controlled variable frequency oscillator 11, a prescaler 12, a frequency dividing circuit 13, a temperature-compensated crystal oscillator 14, and a phase comparison. circuit 1
It is composed of a phase-locked loop consisting of 5 parts. 2 is a second frequency generator using a frequency synthesizer that generates a second local oscillation signal for reception, and includes a voltage-controlled frequency variable oscillator 21, a prescaler 22, and a frequency dividing circuit 23.
, a temperature compensated crystal oscillator 24 and a phase comparator circuit 25. 3 is a waveform generation circuit that generates a baseband signal, and 4 is an orthogonal modulator that orthogonally modulates a carrier wave based on the first local oscillation signal from the first frequency generator 1 with the baseband signal from the waveform generation circuit 3. , the first from the first frequency generator 1
A frequency divider circuit 41 that divides the frequency of a local oscillation signal by four to generate a carrier wave with a precise 90° phase difference, and a modulation circuit that modulates the carrier wave from the frequency divider circuit 41 with the baseband signal from the waveform generation circuit 3. , and a low-pass filter 43 that extracts a fundamental modulated wave from the output signal of the analog switch 42. Reference numeral 5 denotes an up-converter that mixes the fundamental modulated wave output from the orthogonal modulation circuit 4 and the second local oscillation signal from the second frequency generator to generate a transmitted modulated wave at a predetermined transmission frequency. 6 is a reception demodulation section, and a down converter 6 mixes the reception frequency and the second local oscillation signal.
2, and a demodulation circuit 62 that receives the output of the down converter 62 and performs demodulation.

【0003】次に、動作について説明する。第1の周波
数発生器1の電圧制御型周波数可変発振器11は、搬送
波が持つ送信周波数の4倍の周波数を有する第1局部発
振信号を発生する。この第1局部発振信号は直交変調器
4に入力されて分周回路41で4分周され、互いに90
°の位相差を持つ搬送波となってアナログスイッチ42
に入力される。アナログスイッチ42は入力した搬送波
を波形生成回路3からのベースバンド信号により変調し
てローパスフィルタ43に送る。ローパスフィルタ43
は入力した変調出力中から基本変調波を抽出して、アッ
プコンバータ5に出力する。アップコンバータ5はこの
基本波周波数と第2の周波数発生器からの第2局部発振
信号とをミキシングして、所定の送信周波数による送信
変調波を生成して出力する。一方、受信復調部6に入力
された第2局部発振信号は、ダウンコンバータ61によ
り受信周波数とミキシングされた後、復調回路62に送
られ復調される。
Next, the operation will be explained. The voltage-controlled variable frequency oscillator 11 of the first frequency generator 1 generates a first local oscillation signal having a frequency four times the transmission frequency of the carrier wave. This first local oscillation signal is input to the quadrature modulator 4 and divided into four by the frequency divider circuit 41, so that the first local oscillation signal is
The analog switch 42 becomes a carrier wave with a phase difference of °.
is input. The analog switch 42 modulates the input carrier wave with the baseband signal from the waveform generation circuit 3 and sends it to the low-pass filter 43. Low pass filter 43
extracts the fundamental modulated wave from the input modulated output and outputs it to the up converter 5. The up-converter 5 mixes this fundamental wave frequency and the second local oscillation signal from the second frequency generator to generate and output a transmission modulated wave at a predetermined transmission frequency. On the other hand, the second local oscillation signal input to the reception demodulator 6 is mixed with the reception frequency by the down converter 61, and then sent to the demodulation circuit 62 and demodulated.

【0004】0004

【発明が解決しようとする課題】従来の周波数分配回路
は以上のように構成されているので、変調を行なうため
の第1局部発振信号と、送信周波数および受信復調周波
数を作成するための第2発振信号を発生する2つの周波
数発生器を必要とし、安価に実現できないという問題が
あった。本発明は上記のような問題を解決するためにな
されたもので、1つの周波数発生器により安価な周波数
分配回路を提供することを目的とする。
[Problem to be Solved by the Invention] Since the conventional frequency distribution circuit is configured as described above, it generates a first local oscillation signal for modulation, and a second local oscillation signal for creating a transmission frequency and a reception demodulation frequency. There is a problem in that it requires two frequency generators to generate oscillation signals, and cannot be realized at low cost. The present invention has been made to solve the above problems, and an object of the present invention is to provide an inexpensive frequency distribution circuit using a single frequency generator.

【0005】[0005]

【課題を解決するための手段】本発明の変調装置の周波
数分配回路は、送信周波数のN/(N+1)倍またはN
/(N−1)倍の局部周波数を発生する周波数発生器と
、この周波数発生器からの局部周波数をN分周する分周
回路と、この分周回路からの分周出力をベースバンド信
号で変調する変調回路と、この変調回路からの変調出力
と前記周波数発生器からの局部周波数により送信周波数
を出力するアップコンバータと、前記周波数発生器また
は前記分周器の出力に基づいて受信用ローカル周波数を
抽出する周波数抽出回路とから構成される。
[Means for Solving the Problems] The frequency distribution circuit of the modulation device of the present invention has a frequency distribution circuit that is N/(N+1) times the transmission frequency or N
/(N-1) times the local frequency, a frequency divider circuit that divides the local frequency from this frequency generator by N, and the divided output from this frequency divider circuit as a baseband signal. a modulation circuit that modulates; an up-converter that outputs a transmission frequency based on the modulation output from the modulation circuit and a local frequency from the frequency generator; and an up-converter that outputs a transmission frequency based on the modulation output from the modulation circuit and a local frequency from the frequency generator; It consists of a frequency extraction circuit that extracts the frequency.

【0006】また、本発明の変調装置の周波数分配回路
は、送信周波数のN倍の局部周波数を発生する周波数発
生器と、この周波数発生器からの局部周波数をN分周し
て受信用ローカル周波数を出力する分周回路と、この分
周回路からの分周出力をベースバンド信号で変調して送
信周波数を出力する変調回路とから構成される。
Further, the frequency distribution circuit of the modulation device of the present invention includes a frequency generator that generates a local frequency N times the transmission frequency, and a local frequency for reception by dividing the local frequency from the frequency generator by N. The frequency dividing circuit outputs a frequency dividing circuit, and a modulating circuit modulates the frequency divided output from the frequency dividing circuit with a baseband signal to output a transmission frequency.

【0007】[0007]

【作用】本発明によれば、送信周波数のN倍、N/(N
+1)倍、N/(N−1)倍の局部発振信号を分周回路
により分周して互いに90°の位相差を持つ搬送波を生
成する。さらに、分周回路の出力または局部発振信号に
基づいて受信用ダウンコンバータのローカル信号を生成
する。
[Operation] According to the present invention, N times the transmission frequency, N/(N
+1) and N/(N-1) times the frequency of the local oscillation signal is divided by a frequency dividing circuit to generate carrier waves having a phase difference of 90 degrees. Furthermore, a local signal for the receiving down converter is generated based on the output of the frequency dividing circuit or the local oscillation signal.

【0008】[0008]

【実施例】以下、本発明の実施例を図について説明する
。図1は本発明に係る変調装置の周波数分配回路の一実
施例を示すブロック図であり、図4と同一部分は同一符
号を付し、その説明は省略する。図において、7は周波
数発生器であり、送信周波数の4/5倍の局部発振信号
を発生し、直交変調器4の分周回路41とアップコンバ
ータ5に出力する。アップコンバータ5は周波数発生器
7からの局部発振信号と直交変調器4のローパスフィル
タ43からの送信周波数の1/5倍の周波数をミキシン
グして送信周波数を出力する。9は分周回路41から出
力された送信周波数の基本波とその奇数次の高調波出力
(1/5倍、3/5倍、5/5倍、7/5倍…)中より
、受信用ダウンコンバータのローカル周波数を抽出する
バンドパスフィルタである。
Embodiments Hereinafter, embodiments of the present invention will be explained with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a frequency distribution circuit of a modulation device according to the present invention, and the same parts as those in FIG. 4 are given the same reference numerals, and the explanation thereof will be omitted. In the figure, a frequency generator 7 generates a local oscillation signal 4/5 times the transmission frequency and outputs it to the frequency dividing circuit 41 of the quadrature modulator 4 and the up converter 5. The up-converter 5 mixes the local oscillation signal from the frequency generator 7 with a frequency 1/5 times the transmission frequency from the low-pass filter 43 of the orthogonal modulator 4, and outputs a transmission frequency. 9 is for reception from among the fundamental wave of the transmission frequency outputted from the frequency dividing circuit 41 and its odd harmonics (1/5 times, 3/5 times, 5/5 times, 7/5 times...) This is a bandpass filter that extracts the local frequency of the down converter.

【0009】次に、動作について説明する。周波数発生
器7の電圧制御型周波数可変発振器11は、送信周波数
の4/5倍の周波数を有する局部発振信号を発生する。 この局部発振信号は直交変調器4に入力されて分周回路
41で4分周され、周波数が送信周波数の1/4倍で互
いに90°の位相差を持つ搬送波となってアナログスイ
ッチ42に入力される。アナログスイッチ42は、入力
した90゜の位相差を持った送信周波数の1/5倍の搬
送波を、波形生成回路3からのベースバンド信号により
変調してローパスフィルタ43に送る。ローパスフィル
タ43は入力した変調出力中から基本変調波を抽出して
、アップコンバータ5に出力する。アップコンバータ5
は、送信周波数の1/5倍の周波数に基づく基本変調波
と周波数発生器からの送信周波数の4/5倍の局部発振
信号とをミキシングして、所定の送信周波数と同一周波
数による送信変調波を生成して出力する。一方、分周回
路41から送信周波数の1/5倍の周波数を持つ矩形波
を入力するバンドパスフィルタ9は、送信周波数の1/
5倍の基本波とその奇数次の高調波出力中より受信用ダ
ウンコンバータのローカル信号を抽出し、受信復調部6
に入力する。受信復調部6に入力された信号は、ダウン
コンバータ61により受信周波数とミキシングされた後
、復調回路62に送られ復調される。
Next, the operation will be explained. The voltage-controlled variable frequency oscillator 11 of the frequency generator 7 generates a local oscillation signal having a frequency 4/5 times the transmission frequency. This local oscillation signal is input to the quadrature modulator 4 and divided into four by the frequency divider circuit 41 to become a carrier wave with a frequency 1/4 times the transmission frequency and a phase difference of 90 degrees, and is input to the analog switch 42. be done. The analog switch 42 modulates the input carrier wave of 1/5 times the transmission frequency with a phase difference of 90 degrees using the baseband signal from the waveform generation circuit 3 and sends the modulated carrier wave to the low-pass filter 43. The low-pass filter 43 extracts a fundamental modulated wave from the input modulated output and outputs it to the up-converter 5. up converter 5
mixes a basic modulated wave based on a frequency of 1/5 times the transmission frequency and a local oscillation signal of 4/5 times the transmission frequency from a frequency generator to generate a transmission modulated wave at the same frequency as the predetermined transmission frequency. Generate and output. On the other hand, the bandpass filter 9 receives a rectangular wave having a frequency 1/5 times the transmission frequency from the frequency dividing circuit 41.
The local signal of the receiving down converter is extracted from the 5 times the fundamental wave and its odd harmonics output, and the receiving demodulator 6 extracts the local signal of the receiving down converter.
Enter. The signal input to the reception demodulation section 6 is mixed with the reception frequency by a down converter 61, and then sent to a demodulation circuit 62 and demodulated.

【0010】なお、上記実施例では、アップコンバータ
5を用いて送信周波数を得る場合を説明したが、図2に
示すように、アップコンバータを用いることなく送信周
波数を直接変調するように構成しても良い。図2は本発
明の他の実施例を示すブロック図であり、送信周波数の
4倍の局部発振周波数を発生する周波数発生器100を
用いて、送信周発数の4倍の信号を直交変調器4に入力
する。入力した信号は分周回路41で4分周され、送信
周波数で野外に90゜の位相差を持った搬送波となって
アナログスイッチ42に入力し、波形生成回路3からの
ベースバンド信号により変調してローパスフィルタ43
で基本送信変調波を抽出して出力する。一方、分周回路
41で4分周され、周波数が送信周波数と同じ信号が受
信用ダウンコンバータのローカル信号として受信復調部
6に入力され、同様の動作を行なう。
[0010] In the above embodiment, the case where the transmission frequency is obtained using the up-converter 5 has been explained, but as shown in Fig. 2, the transmission frequency can be directly modulated without using the up-converter. Also good. FIG. 2 is a block diagram showing another embodiment of the present invention, in which a frequency generator 100 that generates a local oscillation frequency four times the transmission frequency is used to transmit a signal four times the transmission frequency to a quadrature modulator. Enter 4. The input signal is divided into four by the frequency dividing circuit 41, becomes a carrier wave with a phase difference of 90° at the transmission frequency, is inputted to the analog switch 42, and is modulated by the baseband signal from the waveform generation circuit 3. low pass filter 43
Extracts and outputs the basic transmission modulation wave. On the other hand, a signal whose frequency is divided by four by the frequency dividing circuit 41 and whose frequency is the same as the transmission frequency is inputted to the receiving demodulator 6 as a local signal of the receiving down converter, and the same operation is performed.

【0011】また、図3の他の実施例に示すように、直
交変調器4の分周回路41から受信用のローカル信号を
取り出す代わりに、新たに設けた分周器10により受信
用ローカル信号を取り出すようにしても良い。
Furthermore, as shown in another embodiment of FIG. You may take it out.

【0012】なお、上記各実施例では、分周回路41に
より4分周する場合を説明したが、N分周するようにし
ても良いことはもちろんである。
In each of the above embodiments, the case where the frequency is divided by four by the frequency dividing circuit 41 has been described, but it goes without saying that the frequency may be divided by N.

【0013】[0013]

【発明の効果】以上のように本発明によれば、1つの局
部発振信号を分周し、搬送波と受信用ダウンコンバータ
のローカル信号を生成するように構成したので、1つの
周波数発生器を用意するだけで良く、安価で経済的な変
調装置を得ることができるという効果がある。
As described above, according to the present invention, one local oscillation signal is frequency-divided to generate a carrier wave and a local signal for a receiving down converter, so one frequency generator is prepared. This has the effect that it is possible to obtain an inexpensive and economical modulation device.

【図面の簡単な説明】[Brief explanation of drawings]

【図1】本発明に係る変調装置の周波数分配回路の一実
施例を示すブロック図である。
FIG. 1 is a block diagram showing an embodiment of a frequency distribution circuit of a modulation device according to the present invention.

【図2】本発明に係る変調装置の周波数分配回路の他の
実施例を示すブロック図である。
FIG. 2 is a block diagram showing another embodiment of the frequency distribution circuit of the modulation device according to the present invention.

【図3】本発明に係る変調装置の周波数分配回路の他の
実施例を示すブロック図である。
FIG. 3 is a block diagram showing another embodiment of the frequency distribution circuit of the modulation device according to the present invention.

【図4】従来の変調装置の周波数分配回路を示すブロッ
ク図である。
FIG. 4 is a block diagram showing a frequency distribution circuit of a conventional modulation device.

【符号の説明】[Explanation of symbols]

3  波形生成回路 5  アップコンバータ 6  受信用復調回路 7  周波数発生器 8  直交変調器 9  バンドパスフィルタ 41  分周回路 42  変調回路 43  ローパスフィルタ 3 Waveform generation circuit 5 Up converter 6 Reception demodulation circuit 7 Frequency generator 8 Quadrature modulator 9 Bandpass filter 41 Frequency divider circuit 42 Modulation circuit 43 Low pass filter

Claims (2)

【特許請求の範囲】[Claims] 【請求項1】  送信周波数のN/(N+1)倍または
N/(N−1)倍の局部周波数を発生する周波数発生器
と、この周波数発生器からの局部周波数をN分周する分
周回路と、この分周回路からの分周出力をベースバンド
信号で変調する変調回路と、この変調回路からの変調出
力と前記周波数発生器からの局部周波数により送信周波
数を出力するアップコンバータと、前記周波数発生器ま
たは前記分周器の出力に基づいて受信用ローカル周波数
を抽出する周波数抽出回路とから構成されることを特徴
とする変調装置の周波数分配回路。
Claim 1: A frequency generator that generates a local frequency that is N/(N+1) or N/(N-1) times the transmission frequency, and a frequency divider that divides the local frequency from this frequency generator by N. a modulation circuit that modulates the divided output from the frequency divider circuit with a baseband signal; an up-converter that outputs a transmission frequency based on the modulation output from the modulation circuit and the local frequency from the frequency generator; A frequency distribution circuit for a modulation device, comprising a frequency extraction circuit that extracts a local frequency for reception based on the output of a generator or the frequency divider.
【請求項2】  送信周波数のN倍の局部周波数を発生
する周波数発生器と、この周波数発生器からの局部周波
数をN分周して受信用ローカル周波数を出力する分周回
路と、この分周回路からの分周出力をベースバンド信号
で変調して送信周波数を出力する変調回路とから構成さ
れることを特徴とする変調装置の周波数分配回路。
2. A frequency generator that generates a local frequency that is N times the transmission frequency, a frequency dividing circuit that divides the local frequency from this frequency generator by N and outputs a local frequency for reception, and this frequency divider. 1. A frequency distribution circuit for a modulation device, comprising a modulation circuit that modulates a frequency-divided output from the circuit with a baseband signal and outputs a transmission frequency.
JP3107901A 1991-05-14 1991-05-14 Modulator frequency distribution circuit Expired - Fee Related JP2580888B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP3107901A JP2580888B2 (en) 1991-05-14 1991-05-14 Modulator frequency distribution circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP3107901A JP2580888B2 (en) 1991-05-14 1991-05-14 Modulator frequency distribution circuit

Publications (2)

Publication Number Publication Date
JPH04336715A true JPH04336715A (en) 1992-11-24
JP2580888B2 JP2580888B2 (en) 1997-02-12

Family

ID=14470944

Family Applications (1)

Application Number Title Priority Date Filing Date
JP3107901A Expired - Fee Related JP2580888B2 (en) 1991-05-14 1991-05-14 Modulator frequency distribution circuit

Country Status (1)

Country Link
JP (1) JP2580888B2 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6421530B1 (en) 1996-09-20 2002-07-16 Matsushita Electric Industrial Co., Ltd. Radio circuit having a local oscillator frequency which differs from the transmit frequency or the receive frequency and mobile radio apparatus
KR100680398B1 (en) * 2005-05-11 2007-02-08 현대자동차주식회사 Apparatus and method for detecting balance of tire

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6421530B1 (en) 1996-09-20 2002-07-16 Matsushita Electric Industrial Co., Ltd. Radio circuit having a local oscillator frequency which differs from the transmit frequency or the receive frequency and mobile radio apparatus
KR100680398B1 (en) * 2005-05-11 2007-02-08 현대자동차주식회사 Apparatus and method for detecting balance of tire

Also Published As

Publication number Publication date
JP2580888B2 (en) 1997-02-12

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