JPS5834997B2 - Tashiyuuhashingoujiyushinki - Google Patents

Tashiyuuhashingoujiyushinki

Info

Publication number
JPS5834997B2
JPS5834997B2 JP50038706A JP3870675A JPS5834997B2 JP S5834997 B2 JPS5834997 B2 JP S5834997B2 JP 50038706 A JP50038706 A JP 50038706A JP 3870675 A JP3870675 A JP 3870675A JP S5834997 B2 JPS5834997 B2 JP S5834997B2
Authority
JP
Japan
Prior art keywords
signal
frequency
frequency signal
threshold
threshold value
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
Application number
JP50038706A
Other languages
Japanese (ja)
Other versions
JPS51113519A (en
Inventor
邦彦 丹羽
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.)
NEC Corp
Original Assignee
Nippon Electric 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 Nippon Electric Co Ltd filed Critical Nippon Electric Co Ltd
Priority to JP50038706A priority Critical patent/JPS5834997B2/en
Publication of JPS51113519A publication Critical patent/JPS51113519A/en
Publication of JPS5834997B2 publication Critical patent/JPS5834997B2/en
Expired legal-status Critical Current

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Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04QSELECTING
    • H04Q1/00Details of selecting apparatus or arrangements
    • H04Q1/18Electrical details
    • H04Q1/30Signalling arrangements; Manipulation of signalling currents
    • H04Q1/44Signalling arrangements; Manipulation of signalling currents using alternate current
    • H04Q1/444Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies
    • H04Q1/45Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using multi-frequency signalling
    • H04Q1/453Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using multi-frequency signalling in which m-out-of-n signalling frequencies are transmitted

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
  • Mobile Radio Communication Systems (AREA)

Description

【発明の詳細な説明】 この発明は、音声帯域を利用してダイヤル情報等を多周
波信号の形で伝送する帯域内多周波信号方式における多
周波信号受信器に関するものである。
DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a multi-frequency signal receiver in an in-band multi-frequency signal system that transmits dial information and the like in the form of a multi-frequency signal using a voice band.

本発明の多周波信号受信器の基本動作原理は、受信した
多周波信号を各周波数群に分離し、各群の正弦波をある
閾値と比較して矩形波に変換した後前記多周波信号の周
波数を測定するものである。
The basic operating principle of the multi-frequency signal receiver of the present invention is to separate the received multi-frequency signal into each frequency group, compare the sine wave of each group with a certain threshold value, convert it into a rectangular wave, and then convert the multi-frequency signal into a rectangular wave. It measures frequency.

例えば最も簡単な方法としては別途クロックパルスを発
生しておき、前記矩形波の1周期間に入るクロックパル
スの数を計数することによって前記正弦波の周波数が測
定できる。
For example, as the simplest method, the frequency of the sine wave can be measured by separately generating clock pulses and counting the number of clock pulses that enter one cycle of the rectangular wave.

従来この種の受信器においては上記閾値は単一であった
が、本発明の特徴とするところはそれぞれ異なる複数個
の閾値を設けておき、前記正弦波が横切った閾値のうち
極力犬なるものを選択することによって、入力信号レベ
ルに応じて実質的に前記閾値を動かす点にあり、これに
よって多周波信号受信器の誤動作防止機能を強化するこ
とが目的である。
Conventionally, in this type of receiver, the above-mentioned threshold value was single, but the feature of the present invention is that a plurality of threshold values, each different from each other, are provided, and the threshold value crossed by the sine wave is set as much as possible. By selecting , the threshold value is substantially moved according to the input signal level, and the purpose is to strengthen the malfunction prevention function of the multi-frequency signal receiver.

音声帯域内信号方式においては、正規の多周波信号は音
声と同一の帯域を用いて伝送される。
In voice in-band signaling, regular multi-frequency signals are transmitted using the same band as voice.

このため受信器は音声等の擬似信号を多周波信号と誤認
しないようにしなければならない。
Therefore, the receiver must be careful not to misidentify a pseudo signal such as a voice as a multifrequency signal.

多周波信号と擬似信号の差の一つは、前者は振幅の変動
がほとんどないのに対し、後者は相当大きな変動を伴な
うことである。
One of the differences between a multifrequency signal and a pseudo signal is that the former has almost no amplitude fluctuations, whereas the latter has considerably large fluctuations.

しかし前記のタイプの多周波信号受信器において単一の
閾値を用いると、規格で定められた最小振幅の多周波信
号を受信できるようにするため、閾値はかなり低く設定
しなければならない。
However, if a single threshold value is used in a multi-frequency signal receiver of the type mentioned above, the threshold value must be set quite low in order to be able to receive the multi-frequency signal of the minimum amplitude defined by the standard.

このため、入力信号に多少振幅の変動があっても閾値回
路出力の矩形波はほとんど変化せず、正規の多周波信号
として受信されてしまう危険性があった。
For this reason, even if there is some amplitude variation in the input signal, the rectangular wave output from the threshold circuit hardly changes, and there is a risk that it will be received as a regular multi-frequency signal.

この欠点を除くため、本発明の多周波信号受信器では、
複数個のそれぞれ異なる閾値を用意しておき、入力信号
レベルに応じてそのうちの極力犬なるものを選択する。
In order to eliminate this drawback, the multi-frequency signal receiver of the present invention:
A plurality of different threshold values are prepared, and the most dog-like one is selected depending on the input signal level.

こうすると、信号振幅に変動があってピーク値が下がる
と、低い閾値は横切るが、今まで選択されていた比較的
高い閾値は横切らない。
In this way, if the signal amplitude fluctuates and the peak value decreases, the lower threshold will be crossed, but the relatively high threshold that has been selected will not be crossed.

従って得られる矩形波の周期が一定しなくなり、正規の
多周波信号とは判定されず、誤動作を起さない。
Therefore, the period of the obtained rectangular wave will not be constant, and it will not be determined to be a regular multi-frequency signal, and no malfunction will occur.

一方、正規の多周波信号が入力された場合には振幅変動
はほとんどないので、信号のピーク値は選択された閾値
を常に越えるから問題なく動作する。
On the other hand, when a regular multi-frequency signal is input, there is almost no amplitude variation, and the peak value of the signal always exceeds the selected threshold value, so the system operates without problems.

以下、本発明を図面を参照しつつ主として、クロックパ
ルス計数型の多周波信号受信器について説明する。
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings, mainly regarding a clock pulse counting type multi-frequency signal receiver.

第1図は、クロックパルス計数型多周波信号受信器の概
略を示すブロック図である。
FIG. 1 is a block diagram schematically showing a clock pulse counting type multifrequency signal receiver.

入力端子1に印加された多周波信号は低域p波器2、高
域p波器3によって、低群信号4、高群信号5にそれぞ
れ分離される。
A multi-frequency signal applied to the input terminal 1 is separated into a low group signal 4 and a high group signal 5 by a low-frequency p-wave device 2 and a high-frequency p-wave device 3, respectively.

これらの信号は閾値回路8,9によって閾値6,7とそ
れぞれ比較されて矩形波10.11に変換され、低群周
波数測定回路12、高群周波数測定回路13に入力され
る。
These signals are compared with thresholds 6 and 7 by threshold circuits 8 and 9, respectively, and converted into rectangular waves 10 and 11, which are input to a low group frequency measuring circuit 12 and a high group frequency measuring circuit 13.

各周波数測定回路では、別途クロックパルス発生器14
によって発生されるクロックパルス15を、前記矩形波
のタイミングに従って計数処理して周波数が測定される
In each frequency measurement circuit, a separate clock pulse generator 14 is provided.
The frequency is measured by counting the clock pulses 15 generated by the square wave according to the timing of the rectangular wave.

各群の測定結果16,1γは総合判定回路18で最終的
に多周波信号の判定が行なわれて出力端子−19に結果
が出力される。
The measurement results 16 and 1[gamma] of each group are finally judged as multi-frequency signals by the comprehensive judgment circuit 18, and the results are outputted to the output terminal -19.

第2図は、擬似信号が入ったときの第1図の各部波形を
特に低群側について示す図である。
FIG. 2 is a diagram showing waveforms of various parts of FIG. 1 when a pseudo signal is input, especially on the low group side.

低域p波器出力信号4が不規則な信号であるときは誤動
作の心配はないが、第2図に示すように多少振幅変動は
あってもかなり規則的に閾値6を横切る場合には、閾値
回路8の出力10は正規の多周波信号が入ったときの矩
形波と変わりなくなる。
When the output signal 4 of the low-frequency p-wave device is an irregular signal, there is no need to worry about malfunction, but as shown in FIG. The output 10 of the threshold circuit 8 is no different from a rectangular wave when a regular multi-frequency signal is input.

第1図の低群周波数測定回路12は、矩形波10とクロ
ックパルス15とから信号4の周波数を測定しているか
ら、第2図のような場合には正しい多周波信号と認めて
しまうことになる。
Since the low group frequency measurement circuit 12 in FIG. 1 measures the frequency of the signal 4 from the rectangular wave 10 and the clock pulse 15, it will recognize it as a correct multifrequency signal in the case shown in FIG. 2. become.

これが高群でも同時に起ると誤動作を起し、擬似信号で
あるにも拘わらず正規の多周波信号とみなされてしまつ
O このような誤動作を防ぐ対策としては、閾値6を高く設
定し、振巾変動があって波形のピーク値が下がったとき
に閾値を横切らないようにすることが有効と考えられる
If this happens at the same time in the high group, it will cause a malfunction, and even though it is a pseudo signal, it will be regarded as a regular multi-frequency signal.As a measure to prevent such malfunction, set the threshold value 6 high, It is considered effective to prevent the threshold value from being crossed when the peak value of the waveform decreases due to amplitude fluctuation.

しかし多周波信号の受信規格で定められた最少振幅の信
号を受信しなければならないため単一の閾値を与える場
合には高くは設定できない。
However, since it is necessary to receive a signal with the minimum amplitude determined by the multi-frequency signal reception standard, it cannot be set high when a single threshold value is provided.

第3図は本発明の原理を示す波形図である。FIG. 3 is a waveform diagram showing the principle of the present invention.

第3図は一例として、vl、v2.v3の三つの閾値を
設けた場合が示しである。
FIG. 3 shows vl, v2. The case where three threshold values of v3 are provided is shown.

最も低い閾値v1のみを用いた場合には、得られる矩形
波は第3図のaであり前記のごとく誤動作の危険がある
If only the lowest threshold value v1 is used, the resulting rectangular wave is a in FIG. 3, and there is a risk of malfunction as described above.

これに対しvlよりも高い閾値v2を用いれば、振幅変
動があったとき第3図すのように不規則な矩形波となり
正規の多周波信号とは判定されず誤動作は起さない。
On the other hand, if a threshold value v2 higher than vl is used, when there is an amplitude fluctuation, the waveform becomes an irregular rectangular wave as shown in FIG. 3, and is not determined to be a regular multifrequency signal, so that no malfunction occurs.

最も高い閾値■3には達しないので、閾値としてはv2
を選択すればよい。
Since the highest threshold ■3 is not reached, the threshold is v2.
All you have to do is select.

第4図は1本発明の一実施例を示すブロック図であり、
第1図と同一構成要素には同一の番号をつけである。
FIG. 4 is a block diagram showing an embodiment of the present invention,
The same components as in FIG. 1 are given the same numbers.

この実施例では、低群側のみを複数閾値とし、高群側は
単一閾値としているが、両群ともに複数閾値とずれは更
に有効であることは勿論である。
In this embodiment, only the low group side has multiple threshold values, and the high group side has a single threshold value, but it goes without saying that multiple threshold values and deviations for both groups are more effective.

第4図において、低群信¥j4は閾値回路52゜54.
56によって複数の閾i′L!!、51,53.55(
例えは、第8図のV 1 + V 2 t V−3にそ
れぞれ対応)と比較され、矩形波57.58.59(第
3図のa p l) + Cにそれぞれ対応)に変換さ
れ、選択回路60に入力される。
In FIG. 4, the low group signal \j4 is the threshold value circuit 52゜54.
56 for a plurality of thresholds i′L! ! ,51,53.55(
For example, it is compared with V 1 + V 2 t V-3 in FIG. It is input to the selection circuit 60.

これらの矩形波のうちできるだけ高い閾値と比較して得
られた矩形波(第3図の例ではb)を選択回路60で選
択し、出力信号61として周波数測定回路12へ送出す
る。
Among these rectangular waves, the rectangular wave (b in the example of FIG. 3) obtained by comparing with the highest possible threshold is selected by the selection circuit 60 and sent to the frequency measurement circuit 12 as an output signal 61.

周波数測定回路12はり「コックパルス15を計数して
入力矩形波61の周波数(即ち低群信号4の周波数)を
測定し、測定結果16を出力する。
The frequency measuring circuit 12 counts the cock pulses 15 to measure the frequency of the input rectangular wave 61 (that is, the frequency of the low group signal 4), and outputs a measurement result 16.

総合判定回路18は、低群周波数測定結果16と高群周
波数測定結果11とから最終的に入力多周波信号を判定
し、その結果を信号19として出力する。
The comprehensive determination circuit 18 finally determines the input multi-frequency signal from the low group frequency measurement result 16 and the high group frequency measurement result 11, and outputs the result as a signal 19.

一旦選択された矩形波は周波数測定が行なわれている間
は継続して用いられるが、周波数測定または総合判定の
結果入力信号が正規の多周波信号ではないと判定されれ
ば直ちにリセットされ、入力信号に応じて新たに選択し
直される。
Once selected, the rectangular wave is used continuously while frequency measurement is being performed, but if it is determined that the input signal is not a regular multifrequency signal as a result of frequency measurement or comprehensive judgment, it is immediately reset and input A new selection is made in response to the signal.

また信号が、今まで選択されていた閾値よりも高い閾値
を越した場合はその高い方の閾値と比較して得られる矩
形波が新たに選択される。
Further, if the signal exceeds a threshold higher than the previously selected threshold, a rectangular wave obtained by comparison with the higher threshold is newly selected.

このように選択される矩形波が変化した場合には、その
時点から新たに周波数測定が行なわれる。
When the selected rectangular wave changes in this way, a new frequency measurement is performed from that point onwards.

第5図は、複数閾値の閾値回路および選択回路60の具
体的な一実施例を示す図である。
FIG. 5 is a diagram showing a specific example of the threshold circuit and selection circuit 60 for multiple threshold values.

閾値51.53,55はそれぞれ低、中、高の閾値(例
えば第3図のvl、v2.v3)とする。
Thresholds 51, 53, and 55 are low, medium, and high thresholds (eg, vl, v2, v3 in FIG. 3), respectively.

低群信号4を高閾値55と比較して得られる信号59は
、フリップフロップ67のセット入力として与えられる
A signal 59 obtained by comparing the low group signal 4 with the high threshold 55 is provided as a set input to a flip-flop 67.

今信号4が高閾値55よりも高いピーク値をもっている
場合を考える。
Now consider the case where signal 4 has a peak value higher than high threshold value 55.

この時一旦信号が1′”になるとフリップフロップ61
はセットされ、フリップフロップの出力信号68は1“
′となる。
At this time, once the signal becomes 1''', the flip-flop 61
is set and the output signal 68 of the flip-flop is 1"
'.

これによって、中間値53と比較されて得られた矩形波
58はゲート69によって禁止される。
Thereby, the square wave 58 obtained by comparison with the intermediate value 53 is inhibited by the gate 69.

フリップフロップ6γがセットされたということは、フ
リップフロップ63は必ずセットされている(伺故なら
ば、閾値53は閾値55よりも低い)から、低閾値51
と比較されて得られた矩形波57もゲ−l−65によっ
て禁止され、結局オアゲート71を通って信号61とな
るのは、高閾値55と比較されて得られる矩形波59と
なる。
The fact that the flip-flop 6γ is set means that the flip-flop 63 is always set (if that is the case, the threshold value 53 is lower than the threshold value 55), so the low threshold value 51
The square wave 57 obtained by comparing with the high threshold value 55 is also inhibited by the gate 1-65, and what ultimately passes through the OR gate 71 and becomes the signal 61 is the square wave 59 obtained by comparing with the high threshold value 55.

同様に考えると、信号4のピーク値が高閾値55と中間
像53との中間にある場合は矩形波58が、また信号4
のピーク値が中間像53と低閾値51との中間にある場
合は矩形波57が、それぞれ信号61として周波数測定
回路へ入力される。
Considering the same way, if the peak value of the signal 4 is between the high threshold value 55 and the intermediate image 53, the rectangular wave 58 and the signal 4
When the peak value of is between the intermediate image 53 and the low threshold value 51, the rectangular wave 57 is inputted to the frequency measurement circuit as a signal 61, respectively.

この場合、最低閾値51は、多周波信号受信規格で定め
られた最小振幅の多周波信号を受信できるように設定し
ておかなければならない。
In this case, the minimum threshold value 51 must be set so that a multifrequency signal with the minimum amplitude defined by the multifrequency signal reception standard can be received.

また、一旦セットされたフリップフロップ63.67は
、周波数測定または総合判定の結果、入力信号が正規の
多周波信号ではないと判定されると直ちにその判定結果
62によってリセットされ、閾値は新たに選択し直され
る。
Furthermore, once the flip-flops 63 and 67 are set, as a result of frequency measurement or comprehensive judgment, if it is judged that the input signal is not a regular multi-frequency signal, they are immediately reset based on the judgment result 62, and the threshold value is newly selected. will be redone.

閾値の個数は、多いほど入力信号の広いレベル範囲にわ
たって一定した誤動作防止機能が期待できる。
The greater the number of threshold values, the more consistent the malfunction prevention function can be expected over a wider level range of input signals.

なお本文では主にクロックパルス計数型多周波信号受信
器に適用した例について説明したが、本発明は一般に多
周波信号を矩形波に変換してからその周波数を測定する
タイプの多周波信号受信器にはすべて適用可能である。
Although this text mainly describes an example applied to a clock pulse counting type multi-frequency signal receiver, the present invention generally applies to a multi-frequency signal receiver of the type that converts a multi-frequency signal into a rectangular wave and then measures the frequency. All are applicable.

たとえば、現在実用化されている多周波信号受信器の方
式は各群の多周波信号を矩形波に変換後、各多周波信号
周波数に同調した共振回路群に通して周波数を判定する
ものであるが、このような方式にも適用できる。
For example, the method of multi-frequency signal receivers currently in practical use converts each group of multi-frequency signals into a rectangular wave, and then passes it through a group of resonant circuits tuned to the frequency of each multi-frequency signal to determine the frequency. However, it can also be applied to such a method.

以上説明したように、本発明の多周波信号受信器は、自
ら誤動作防止機能を備えたものであって擬似信号に対す
る防護の点できわめて有効である。
As explained above, the multi-frequency signal receiver of the present invention has its own malfunction prevention function and is extremely effective in protecting against pseudo signals.

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

第1図は、本発明の適用の対象となる多周波信号受信器
の一例を示すブロック図で、1は入力端子、2は低域P
波器、3は高域p波器、6,7は閾値、8,9は閾値回
路、12.13は周波数測定回路、14はクロックパル
ス発生器、18は総合判定回路、19は出力端子である
。 第2図は、第1図の回路の各部波形を示す図であり、擬
似信号によって誤動作を起す場合の一例を示している。 第3図は、本発明の多周波信号受信器で誤動作の防止で
きる原理を示す波形図である。 第4図は、本発明の一実施例を示すブロック図で、51
,53.55はそれぞれ低、甲、高閾値、52,54,
56は閾値回路、60は選択回路である。 第5図は、第4図の閾値回路および選択回路の一実施例
を示す回路図で、63.67はフリップフロップ、62
はリセット信号である。
FIG. 1 is a block diagram showing an example of a multi-frequency signal receiver to which the present invention is applied.
12.13 is a frequency measurement circuit, 14 is a clock pulse generator, 18 is a comprehensive judgment circuit, 19 is an output terminal. be. FIG. 2 is a diagram showing waveforms of various parts of the circuit of FIG. 1, and shows an example of a case where a false signal causes a malfunction. FIG. 3 is a waveform diagram showing the principle by which malfunctions can be prevented in the multi-frequency signal receiver of the present invention. FIG. 4 is a block diagram showing one embodiment of the present invention.
, 53.55 are the low, instep, and high thresholds, respectively, and 52, 54,
56 is a threshold circuit, and 60 is a selection circuit. FIG. 5 is a circuit diagram showing an embodiment of the threshold circuit and selection circuit of FIG. 4, in which 63.67 is a flip-flop;
is a reset signal.

Claims (1)

【特許請求の範囲】[Claims] 1 多周波信号の周波数群を分離して各群の正弦波を得
る手段と、該正弦波振幅をそれぞれ異なる閾値と比較す
る複数の比較回路と、前記正弦波が横切った閾値のうち
極力犬なる閾値の比較回路の出力矩形波を選択する手段
と該選択された矩形波を用いて前記多周波信号の各群の
周波数を測定する手段と、該各群の周波数の測定結果を
もとにどの多周波信号を受信したかを判定する総合判定
回路とを備えたことを特徴とする多周波信号受信器。
1 means for separating frequency groups of a multi-frequency signal to obtain sine waves for each group; a plurality of comparison circuits for comparing the sine wave amplitudes with different threshold values; means for selecting the output rectangular wave of the threshold comparison circuit; means for measuring the frequency of each group of the multi-frequency signal using the selected rectangular wave; A multi-frequency signal receiver comprising: a comprehensive determination circuit that determines whether a multi-frequency signal has been received.
JP50038706A 1975-03-31 1975-03-31 Tashiyuuhashingoujiyushinki Expired JPS5834997B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP50038706A JPS5834997B2 (en) 1975-03-31 1975-03-31 Tashiyuuhashingoujiyushinki

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP50038706A JPS5834997B2 (en) 1975-03-31 1975-03-31 Tashiyuuhashingoujiyushinki

Publications (2)

Publication Number Publication Date
JPS51113519A JPS51113519A (en) 1976-10-06
JPS5834997B2 true JPS5834997B2 (en) 1983-07-30

Family

ID=12532748

Family Applications (1)

Application Number Title Priority Date Filing Date
JP50038706A Expired JPS5834997B2 (en) 1975-03-31 1975-03-31 Tashiyuuhashingoujiyushinki

Country Status (1)

Country Link
JP (1) JPS5834997B2 (en)

Also Published As

Publication number Publication date
JPS51113519A (en) 1976-10-06

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