JPH0530342B2 - - Google Patents
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- Publication number
- JPH0530342B2 JPH0530342B2 JP60072369A JP7236985A JPH0530342B2 JP H0530342 B2 JPH0530342 B2 JP H0530342B2 JP 60072369 A JP60072369 A JP 60072369A JP 7236985 A JP7236985 A JP 7236985A JP H0530342 B2 JPH0530342 B2 JP H0530342B2
- Authority
- JP
- Japan
- Prior art keywords
- output
- frequency
- circuit
- amplifier
- detection circuit
- 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.)
- Expired - Lifetime
Links
- 238000001514 detection method Methods 0.000 claims description 45
- 238000007493 shaping process Methods 0.000 claims description 13
- 230000003321 amplification Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000003199 nucleic acid amplification method Methods 0.000 description 2
- 238000011896 sensitive detection Methods 0.000 description 2
- 230000008054 signal transmission Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
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- Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
- Circuits Of Receivers In General (AREA)
Description
【発明の詳細な説明】
〔産業上の利用分野〕
この発明は、たとえば、赤外線を信号伝送手段
とする制御装置のリモートコントロール受信回路
に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to, for example, a remote control receiving circuit for a control device using infrared rays as a signal transmission means.
赤外線を信号伝送手段に用いた制御装置は、た
とえば、TV受像機などにおいて、受信周波数チ
ヤンネルの切換え、音量の加減などの操作に用い
られているが、操作モードの増加に応じて周波数
の異なる２以上の信号を切り換えれば、単一の周
波数を用いる場合に比較してより多くの操作が可
能になる。
Control devices that use infrared rays as a signal transmission means are used, for example, in TV receivers, etc., for operations such as switching reception frequency channels and adjusting volume. By switching these signals, more operations can be performed than when using a single frequency.
しかながら、受信すべき周波数f1，f2を受信帯
域に設定した複数の増幅器を設置し、各増幅器の
出力を個別に検波回路を介してピーク値検波を行
えば、それぞれの周波数f1，f2の受信信号が検出
可能であるが、高感度の検波回路をチヤンネルご
とに設置しなければならず、回路構成の複雑化、
高価になるなどの欠点がある。
However, if a plurality of amplifiers whose reception bands are set to receive frequencies f 1 and f 2 are installed, and the output of each amplifier is individually subjected to peak value detection via a detection circuit, the respective frequencies f 1 and It is possible to detect f2 received signals, but a highly sensitive detection circuit must be installed for each channel, which increases the complexity of the circuit configuration.
It has disadvantages such as being expensive.
また、受信すべき周波数f1，f2を受信帯域に設
定した複数の増幅器の後に単一の検波回路を設置
してピーク値検波を行う場合には、各周波数f1，
f2でパルス変調したパルス出力の時間幅が同一に
なると、周波数が異なる場合にも受信出力は同一
となり、両者の判別をすることができない。 In addition, when performing peak value detection by installing a single detection circuit after multiple amplifiers whose reception bands are set to receive frequencies f 1 and f 2 , each frequency f 1 and
If the time widths of the pulse outputs pulse-modulated by f 2 are the same, the received outputs will be the same even if the frequencies are different, making it impossible to distinguish between the two.
そこで、この発明は、周波数の異なる複数の信
号を送信する場合に、何れの周波数の信号かを判
別可能にしようとするとともに、検波回路など主
信号系統の簡略化を図ろうとするものである。 Therefore, when transmitting a plurality of signals with different frequencies, the present invention attempts to make it possible to determine which frequency the signal is, and to simplify the main signal system such as the detection circuit.
この発明のリモートコントロール受信回路は、
第１図に例示するように、周波数が異なる複数の
信号を受信するリモートコントロール受信回路で
あつて、
受信すべき周波数に応じて設定され、その周波
数の信号を個別に増幅する第１の増幅器４Ａ，４
Ｂと、この第１の増幅器の周波数を混合して増幅
する第２の増幅器（ミキシング増幅器６）と、こ
の第２の増幅器の出力から前記信号を検波する第
１の検波回路８と、この第１の検波回路の検波出
力の波形を整形する波形整形回路１０と、前記第
１の増幅器の出力から検出すべき周波数毎に設け
られてその周波数毎に信号を検波する第２の検波
回路１８Ａ，１８Ｂと、前記第２の検波回路の各
検波出力のレベルを比較して周波数を判別する判
別手段２０と、前記波形整形回路の出力部と、取
り出すべき周波数に対応する複数の出力端子との
間に設けられ、前記判別手段の出力に応じて前記
波形整形出力を選択し、対応する前記出力端子に
前記波形整形出力を切り換えて出力させるスイツ
チ回路１４とを備えたことを特徴とするものであ
る。
The remote control receiving circuit of this invention includes:
As illustrated in FIG. 1, it is a remote control receiving circuit that receives a plurality of signals with different frequencies, and includes a first amplifier 4A that is set according to the frequency to be received and that individually amplifies the signal of that frequency. ,4
B, a second amplifier (mixing amplifier 6) that mixes and amplifies the frequency of the first amplifier, a first detection circuit 8 that detects the signal from the output of the second amplifier, and a first detection circuit 8 that detects the signal from the output of the second amplifier. a waveform shaping circuit 10 that shapes the waveform of the detection output of the first detection circuit; a second detection circuit 18A that is provided for each frequency to be detected from the output of the first amplifier and detects a signal for each frequency; 18B, a determining means 20 for determining the frequency by comparing the levels of each detection output of the second detection circuit, the output section of the waveform shaping circuit, and a plurality of output terminals corresponding to the frequencies to be extracted. The apparatus is characterized in that it is provided with a switch circuit 14 which selects the waveform-shaped output according to the output of the discrimination means, and switches the waveform-shaped output to the corresponding output terminal to output the waveform-shaped output. .
受信周波数に対応して第１の増幅器が設置され
ており、入力信号は第１の増幅器によつて増幅さ
れる。第１の増幅器の出力は第２の増幅器によつ
て増幅された後、第１の検波回路によつて検波が
施される。この第１の検波回路の検波出力は波形
整形回路によつて波形整形が行われ、その波形整
形出力がスイツチ回路に加えられる。
A first amplifier is installed corresponding to the reception frequency, and the input signal is amplified by the first amplifier. The output of the first amplifier is amplified by the second amplifier, and then detected by the first detection circuit. The detected output of the first detection circuit is subjected to waveform shaping by a waveform shaping circuit, and the waveform shaped output is applied to the switch circuit.
このような主信号系統に対し、第２の検波回路
は、受信周波数を検出するために設置されたもの
であり、第２の検波回路では受信周波数を個別に
検波する。この検波出力が判別手段に加えられ
て、両者のレベルが比較され、その結果、受信周
波数の判別が行われる。 For such a main signal system, the second detection circuit is installed to detect the reception frequency, and the second detection circuit individually detects the reception frequency. This detection output is applied to the discrimination means, the levels of both are compared, and as a result, the receiving frequency is discriminated.
そして、この判別手段の判別出力は、スイツチ
回路に対する切換制御入力として加えられ、対応
する出力端子に対して出力の選択が行われる。し
たがつて、周波数に対応して設けられた出力端子
から所定周波数の波形整形出力が取り出される。 The discrimination output of this discrimination means is applied as a switching control input to the switch circuit, and the output is selected for the corresponding output terminal. Therefore, a waveform shaped output of a predetermined frequency is taken out from an output terminal provided corresponding to the frequency.
以下、この発明の実施例を図面を参照して詳細
に説明する。
Embodiments of the present invention will be described in detail below with reference to the drawings.
第１図はこの発明のリモートコントロール受信
回路の実施例を示している。 FIG. 1 shows an embodiment of the remote control receiving circuit of the present invention.
第１図において、入力端子２には、図示してい
ない受光素子が接続され、搬送赤外線が電気信号
に変換されて加えられる。送信信号の受信すべき
周波数に応じてその周波数の信号を個別に増幅す
る第１の増幅器として、周波数f1，f2の２モード
では、周波数f1を増幅帯域とする増幅器４Ａと、
周波数f2を増幅帯域とする増幅器４Ｂが設置され
ている。 In FIG. 1, a light receiving element (not shown) is connected to the input terminal 2, and the carrier infrared rays are converted into an electrical signal and applied thereto. In the two modes of frequencies f 1 and f 2 , an amplifier 4A whose amplification band is the frequency f 1 as a first amplifier that individually amplifies signals of the frequency according to the frequency to be received of the transmitted signal;
An amplifier 4B whose amplification band is frequency f2 is installed.
各増幅器４Ａ，４Ｂの増幅出力は、第２の増幅
器としてのミキシング増幅器６に加えられて混合
された後、第１の検波回路としての検波回路８に
加えられて検波される。この検波回路８は、ミキ
シング増幅器６の出力信号のピーク値を検出する
ピーク値検出回路で構成されている。 The amplified outputs of the respective amplifiers 4A and 4B are applied to a mixing amplifier 6 as a second amplifier and mixed, and then applied to a detection circuit 8 as a first detection circuit to be detected. The detection circuit 8 is composed of a peak value detection circuit that detects the peak value of the output signal of the mixing amplifier 6.
この検波回路８の検波出力は、波形整形回路１
０に加えられて波形整形された後、出力回路１２
を介して出力を振り分けるスイツチ回路１４に加
えられ、周波数f1，f2の出力Vpf1，Vpf2は出力端
子１６ａ，１６ｂから出力される。 The detection output of this detection circuit 8 is the waveform shaping circuit 1
0 and is waveform shaped, the output circuit 12
The outputs V pf1 and V pf2 at frequencies f 1 and f 2 are outputted from output terminals 16a and 16b.
そして、増幅器４Ａ，４Ｂの出力側には、検出
すべき周波数毎に設けられて周波数毎に信号を検
波する第２の検波回路として出力に対応して周波
数f1の信号を検波する検波回路１８Ａ、周波数f2
の信号を検波する検波回路１８Ｂが設置されてい
るとともに、各検波回路１８Ａ，１８Ｂの検波出
力から何れの周波数f1，f2の信号かを判別する判
別手段２０が設置されている。各検波回路１８
Ａ，１８Ｂは、たとえば、各増幅器４Ａ，４Ｂの
出力を整流してその増幅出力に応じた直流レベル
に変換する整流回路や増幅出力を単に積分する積
分回路で構成される。 On the output side of the amplifiers 4A and 4B, a detection circuit 18A is provided for each frequency to be detected and serves as a second detection circuit for detecting a signal for each frequency. , frequency f 2
A detection circuit 18B is installed to detect the signal, and a determination means 20 is installed to determine which frequency f 1 or f 2 the signal belongs to from the detection output of each detection circuit 18A or 18B. Each detection circuit 18
A, 18B are constituted by, for example, a rectifier circuit that rectifies the output of each amplifier 4A, 4B and converts it to a DC level according to the amplified output, and an integrating circuit that simply integrates the amplified output.
また、この実施例の場合、判別手段２０は、検
波回路１８Ａ，１８Ｂの直流出力のレベルを比較
し、何れの周波数f1，f2の出力かを判別する比較
器２２で構成されている。この場合、検波回路１
８Ａの出力がその非反転入力端子（＋）に加えら
れ、検波回路１８Ｂの出力がその反転入力端子
（−）に加えられているから、比較器２２の出力
が高レベルＨのとき周波数f1の信号、その出力が
低レベルＬのとき周波数f2の信号が到来している
ことが判る。 In the case of this embodiment, the determining means 20 includes a comparator 22 that compares the levels of the DC outputs of the detection circuits 18A and 18B and determines which frequency f 1 or f 2 the output has. In this case, the detection circuit 1
Since the output of 8A is applied to its non-inverting input terminal (+) and the output of the detection circuit 18B is applied to its inverting input terminal (-), when the output of the comparator 22 is at a high level H, the frequency f 1 It can be seen that when the output of the signal is at a low level L, a signal of frequency f 2 is arriving.
この比較器２２が発生する判別出力Vpsは、出
力端子２４から周波数判別出力として出力される
とともに、出力回路１２の出力側に設置されたス
イツチ回路１４の切換信号として加えられてい
る。すなわち、スイツチ回路１４は、周波数に応
じてその出力端子１６ａ，１６ｂに発生する出力
Vpf1，Vpf2を切り換える手段で構成され、たとえ
ば、リレーなどの電気機械的なスイツチや差動増
幅器などの電子的なスイツチング回路で構成され
る。 The discrimination output V ps generated by the comparator 22 is output as a frequency discrimination output from an output terminal 24 and is also added as a switching signal to a switch circuit 14 installed on the output side of the output circuit 12 . That is, the switch circuit 14 outputs the outputs generated at its output terminals 16a and 16b according to the frequency.
It consists of a means for switching V pf1 and V pf2 , for example, an electromechanical switch such as a relay, or an electronic switching circuit such as a differential amplifier.
以上のように構成したので、第２図のＡに示す
周波数f1，f2の信号が順次に到来した場合、増幅
器４Ａ，４Ｂは出力を発生し、この増幅出力は検
波回路８で検波された後、波形整形回路１０で波
形整形され、第２図のＢに示すパルス出力が出力
回路１２を介してスイツチ回路１４に加えられ
る。 With the above configuration, when the signals of frequencies f 1 and f 2 shown in A in FIG. After that, the waveform is shaped by the waveform shaping circuit 10, and the pulse output shown in B in FIG. 2 is applied to the switch circuit 14 via the output circuit 12.
この場合、増幅器４Ａの出力は、検波回路１８
Ａで検波され、その出力は、第２図のＣに示すよ
うに、Ｈ（高電位）出力となるので、比較器２２
はＨ出力となり、周波数f1を受信していることを
示す判別出力Vpsが出力端子２４から出力される。
このとき、その判別出力Vpsに応じてスイツチ回
路１４が出力端子１６ａ側に切り換えられるの
で、出力端子１６ａには、第２図のＥに示す周波
数f1の出力Vpf1が発生する。 In this case, the output of the amplifier 4A is
The wave is detected by A, and its output becomes an H (high potential) output as shown in C in FIG. 2, so the comparator 22
becomes an H output, and a discrimination output V ps indicating that frequency f 1 is being received is output from the output terminal 24.
At this time, the switch circuit 14 is switched to the output terminal 16a side in accordance with the discrimination output V ps , so that an output V pf1 having a frequency f 1 shown at E in FIG. 2 is generated at the output terminal 16a.
また、周波数f2の信号が到来している場合、増
幅器４Ｂの出力は、検波回路１８Ｂで検波され、
その出力は、第２図のＤに示すように、Ｈ出力と
なるので、比較器２２はＬ（低電位）出力となり、
周波数f2を受信していることを示す判別出力Vps
を出力端子２４から出力する。このとき、その判
別出力Vpsに応じてスイツチ回路１４は出力端子
１６ｂ側に切り換えられ、出力端子１６ｂには、
第２図のＦに示す周波数f2の出力Vpf2が発生す
る。 Further, when a signal with frequency f 2 is arriving, the output of the amplifier 4B is detected by the detection circuit 18B,
As shown in D in FIG. 2, the output is an H output, so the comparator 22 becomes an L (low potential) output.
Discrimination output V ps indicating that frequency f 2 is being received
is output from the output terminal 24. At this time, the switch circuit 14 is switched to the output terminal 16b side according to the discrimination output V ps , and the output terminal 16b has a
An output V pf2 of frequency f 2 shown at F in FIG. 2 is generated.
このように周波数f1，f2の判別を行うことがで
きるので、第２図のＡに示す周波数f1，f2のよう
に異なるミキシング周波数６を持ちながら送信信
号の時間幅Ｔが同一になるような場合にも、その
判別を行うことができ、多くのモード切換えなど
多数の情報を送信し、判別が可能になり、多機能
化が実現される。 Since the frequencies f 1 and f 2 can be discriminated in this way, the time width T of the transmitted signal is the same even though the frequencies f 1 and f 2 have different mixing frequencies 6 as shown in A in Fig. 2. Even in such cases, it can be determined, and a large amount of information such as many mode changes can be transmitted, making the determination possible and realizing multi-functionality.
なお、各検波回路１８Ａ，１８Ｂの出力が共に
Ｌ出力となる場合には、比較器２２はＬ出力とな
るが、周波数f1，f2の信号の到来は別の手段で検
出できるので、周波数f1，f2の判別を損なうこと
はない。 Note that when the outputs of the detection circuits 18A and 18B both become L outputs, the comparator 22 becomes L outputs, but since the arrival of the signals of frequencies f 1 and f 2 can be detected by another means, the frequency This does not impair the discrimination between f 1 and f 2 .
実施例では、周波数f1，f2で構成される２チヤ
ンネルを例に採つて説明したが、３以上の周波数
の受信、判別も可能である。この場合、判別手段
２０は、複数の比較器や論理回路を用いて検波出
力から周波数の判別を行うことができるので、チ
ヤンネル数が増加しても、検波回路８などの主信
号系統は単一構成となり、回路構成の簡略化とと
もに、高感度の検波回路を２以上用いる必要がな
いため、安価に構成できる。 Although the embodiment has been described using two channels consisting of frequencies f 1 and f 2 as an example, it is also possible to receive and discriminate three or more frequencies. In this case, the discrimination means 20 can discriminate the frequency from the detection output using a plurality of comparators and logic circuits, so even if the number of channels increases, the main signal system such as the detection circuit 8 is In addition to simplifying the circuit configuration, there is no need to use two or more highly sensitive detection circuits, so the configuration can be made at low cost.
以上説明したように、この発明によれば、周波
数の異なる信号を受信し、その受信信号が何れの
周波数かを確実に判別でき、多くのモード切換え
など多機能化を図ることができるとともに、高感
度の検波回路をチヤンネルごとに設置する必要が
なく、回路構成の簡略化、低価格化などを図るこ
とができる。
As explained above, according to the present invention, it is possible to receive signals with different frequencies and reliably determine which frequency the received signal is, and it is possible to achieve multifunctionality such as switching many modes, and also to achieve high performance. There is no need to install a sensitivity detection circuit for each channel, and the circuit configuration can be simplified and the cost reduced.
第１図はこの発明のリモートコントロール受信
回路の実施例を示すブロツク図、第２図はその動
作波形を示す説明図である。
４Ａ，４Ｂ……増幅器（第１の増幅器）、６…
…ミキシング増幅器（第２の増幅器）、８……第
１の検波回路、１０……波形整形回路、１４……
スイツチ回路、１６ａ，１６ｂ……出力端子、１
８Ａ，１８Ｂ……第２の検波回路、２０……判別
手段、２２……比較器。
FIG. 1 is a block diagram showing an embodiment of the remote control receiving circuit of the present invention, and FIG. 2 is an explanatory diagram showing its operating waveforms. 4A, 4B...Amplifier (first amplifier), 6...
...mixing amplifier (second amplifier), 8...first detection circuit, 10...waveform shaping circuit, 14...
Switch circuit, 16a, 16b...output terminal, 1
8A, 18B...Second detection circuit, 20...Discrimination means, 22...Comparator.
Claims (1)
トコントロール受信回路であつて、 受信すべき周波数に応じて設定され、その周波
数の信号を個別に増幅する第１の増幅器と、 この第１の増幅器の周波数を混合して増幅する
第２の増幅器と、 この第２の増幅器の出力から前記信号を検波す
る第１の検波回路と、 この第１の検波回路の検波出力の波形を整形す
る波形整形回路と、 前記第１の増幅器の出力から検出すべき周波数
毎に設けられてその周波数毎に信号を検波する第
２の検波回路と、 前記第２の検波回路の各検波出力のレベルを比
較して周波数を判別する判別手段と、 前記波形整形回路の出力部と、取り出すべき周
波数に対応する複数の出力端子との間に設けら
れ、前記判別手段の出力に応じて前記波形整形出
力を選択し、対応する前記出力端子に前記波形整
形出力を切り換えて出力させるスイツチ回路と、 を備えたことを特徴とするリモートコントロール
受信回路。[Claims] 1. A remote control receiving circuit that receives a plurality of signals with different frequencies, comprising: a first amplifier that is set according to the frequency to be received and that individually amplifies the signals of that frequency; a second amplifier that mixes and amplifies the frequency of the first amplifier; a first detection circuit that detects the signal from the output of the second amplifier; and a waveform of the detection output of the first detection circuit. a waveform shaping circuit for shaping; a second detection circuit provided for each frequency to be detected from the output of the first amplifier and detecting a signal for each frequency; and a waveform shaping circuit for each detection output of the second detection circuit. a discriminating means for discriminating frequencies by comparing levels; and a discriminating means provided between the output section of the waveform shaping circuit and a plurality of output terminals corresponding to frequencies to be extracted, and shaping the waveform according to the output of the discriminating means. A remote control receiving circuit comprising: a switch circuit that selects an output and outputs the waveform shaping output to the corresponding output terminal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60072369A JPS61230549A (en) | 1985-04-05 | 1985-04-05 | Remote control reception circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60072369A JPS61230549A (en) | 1985-04-05 | 1985-04-05 | Remote control reception circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61230549A JPS61230549A (en) | 1986-10-14 |
| JPH0530342B2 true JPH0530342B2 (en) | 1993-05-07 |
Family
ID=13487328
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP60072369A Granted JPS61230549A (en) | 1985-04-05 | 1985-04-05 | Remote control reception circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61230549A (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5021724A (en) * | 1973-06-26 | 1975-03-07 | ||
| JPS5961342A (en) * | 1982-09-30 | 1984-04-07 | Matsushita Electric Works Ltd | Power line carrier receiver |
-
1985
- 1985-04-05 JP JP60072369A patent/JPS61230549A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5021724A (en) * | 1973-06-26 | 1975-03-07 | ||
| JPS5961342A (en) * | 1982-09-30 | 1984-04-07 | Matsushita Electric Works Ltd | Power line carrier receiver |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61230549A (en) | 1986-10-14 |
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