JPS61225994A - Multi-frequency signal receiver - Google Patents
Multi-frequency signal receiverInfo
- Publication number
- JPS61225994A JPS61225994A JP60067038A JP6703885A JPS61225994A JP S61225994 A JPS61225994 A JP S61225994A JP 60067038 A JP60067038 A JP 60067038A JP 6703885 A JP6703885 A JP 6703885A JP S61225994 A JPS61225994 A JP S61225994A
- Authority
- JP
- Japan
- Prior art keywords
- frequency
- signal
- frequency signal
- circuit
- filter 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.)
- Pending
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04Q—SELECTING
- H04Q1/00—Details of selecting apparatus or arrangements
- H04Q1/18—Electrical details
- H04Q1/30—Signalling arrangements; Manipulation of signalling currents
- H04Q1/44—Signalling arrangements; Manipulation of signalling currents using alternate current
- H04Q1/444—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies
- H04Q1/45—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using multi-frequency signalling
- H04Q1/453—Signalling 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
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
Abstract
Description
【発明の詳細な説明】
〔発明の技術分野〕
本発明は、例えば電話機の押しボタンダイヤルを操作す
ることにより発生されるDTMF (Dual To
ne Multi Frequency)信号等を
受信し復号化するための多周波信号受信装置の改良に関
する。Detailed Description of the Invention [Technical Field of the Invention] The present invention relates to a DTMF (Dual To
The present invention relates to an improvement of a multi-frequency signal receiving device for receiving and decoding multi-frequency signals and the like.
近年、電話機の押しボタンダイヤルキーの操作により発
生されるDTMF信号を用いてチケットの予約や電気機
器の遠隔制御等を行なうシステムが開発されている。第
5図はそのシステムの概略構成を示すものである。同図
において、電話機1は伝送路2を介して他の電話機3と
対向しており、この電話機3にはDTMF信号受信器4
が並列に接続され、かつこのDTMF信号受信器4には
電子計算機5が接続されている。尚、上記伝送路2は例
えば電話機1が移動機の場合、第6図に示す如く無線回
線21、送受信機22、移動用交換局23、総括局26
、中心局27、集中局28I3よび端局29から構成さ
れる。In recent years, systems have been developed that use DTMF signals generated by operating push-button dial keys on telephones to reserve tickets, remotely control electrical equipment, and the like. FIG. 5 shows a schematic configuration of the system. In the figure, a telephone 1 faces another telephone 3 via a transmission line 2, and this telephone 3 has a DTMF signal receiver 4.
are connected in parallel, and an electronic computer 5 is connected to this DTMF signal receiver 4. Note that, for example, when the telephone 1 is a mobile device, the transmission path 2 includes a radio line 21, a transceiver 22, a mobile switching center 23, and a central office 26, as shown in FIG.
, a central station 27, a centralized station 28I3, and a terminal station 29.
このような構成において、電話機1と電話機3との回線
接続後、電話機1の押しボタンダイヤルキーを操作する
と、この操作により発生されたDTMF信号が伝送路2
を介して相手側のDTMF信号受信器4に送られ、この
受信器4で受信復号化されたのち計算機5に供給されて
この計算機5で例えば列車の座席予約等が行なわれる。In such a configuration, when the push button dial key of the telephone 1 is operated after the line is connected between the telephone 1 and the telephone 3, the DTMF signal generated by this operation is transmitted to the transmission line 2.
The signal is sent to the other party's DTMF signal receiver 4 via the DTMF signal receiver 4, where it is received and decoded, and then supplied to the computer 5, where it is used, for example, to reserve a seat on a train.
ところが、この様なシステムのように無線系に信号の過
大レベルを制限するためのIDC回路が含まれていたり
、また伝送路2に非線形回路が存在すると、伝送路2上
でDTMF信号の三次歪みが発生してこの三次歪みがD
TMF信号受信器4の信号識別動作に悪影響を及ぼすこ
とがあり好ましくなかった。例えば、押しボタンダイヤ
ルキー“舛”は表に示す如く低群周波数fLが9411
h。However, if the wireless system in such a system includes an IDC circuit to limit excessive signal levels, or if a nonlinear circuit is present on the transmission line 2, third-order distortion of the DTMF signal may occur on the transmission line 2. occurs and this third-order distortion is D
This is not preferable because it may have an adverse effect on the signal identification operation of the TMF signal receiver 4. For example, the push button dial key "Masu" has a low group frequency fL of 9411 as shown in the table.
h.
高群周波数f、が12091hであり、これらの周波数
によっ72ft、−fu−673)b、2fo −ft
−1477−なる三次歪みが発生する。これらの三次歪
み成分のレベルが大きくなるとDTMF信号受信器4は
誤検出を起こし、これにより正確な予約業務等を行なえ
なくなることがあった。The high group frequency f, is 12091h, and these frequencies give 72ft, -fu-673)b, 2fo -ft
A third-order distortion of -1477- occurs. When the level of these third-order distortion components becomes large, the DTMF signal receiver 4 causes erroneous detection, which sometimes makes it impossible to perform accurate reservations and the like.
〔発明の目的〕
本発明は、上記欠点に着目してなされたもので、三次歪
みの影響を低減して正確な多周波信号の識別を行ない得
る多周波信号受信装置を提供することを目的とする。[Object of the Invention] The present invention has been made in view of the above-mentioned drawbacks, and an object of the present invention is to provide a multi-frequency signal receiving device that can accurately identify multi-frequency signals by reducing the influence of third-order distortion. do.
本発明は、上記目的を達成するために、伝送路と多周波
信号を受信し復号化する回路との間にフィルタ回路を設
け、このフィルタ回路により伝送路で発生する多周波信
号の三次歪みのうち所定の周波数成分を減衰させて多周
波信号との信号レベル差を拡大するようにしたものであ
る。In order to achieve the above object, the present invention provides a filter circuit between a transmission line and a circuit that receives and decodes a multifrequency signal, and this filter circuit eliminates third-order distortion of the multifrequency signal generated on the transmission line. Among them, a predetermined frequency component is attenuated to enlarge the signal level difference with the multi-frequency signal.
第1図は、本発明の一実施例における多周波信号受信装
置を備えた電話システムの概略構成図で、前記第5図と
同一部分には同一符号を付しである。FIG. 1 is a schematic diagram of a telephone system equipped with a multi-frequency signal receiving device according to an embodiment of the present invention, and the same parts as in FIG. 5 are given the same reference numerals.
多周波信号受信器としてのDTMF信号受信器4は、例
えば第2図に示す如く構成されている。The DTMF signal receiver 4 as a multi-frequency signal receiver is configured as shown in FIG. 2, for example.
すなわち、DTMF信号Isは入力増幅器41およびダ
イヤルトーンフィルタ42を経て高群フィルタ43およ
び低群フ、イルタ44に導入され、これらのフィルタ4
3.44でそれぞれ周波数が判定される。そしてこれら
のフィルタ43.44の判定出力は、それぞれ零り0ス
検出器45.46を介してデジタル検出回路47に導か
れる。このデジタル検出回路47は、入力信号の周期を
高群および低群別に高速クロックで計数することにより
入力DTMF信号の周波数を識別するもので、その識別
出力をコード変換器48に供給する。このコード変換器
48は上記識別出力を計算機5に適した形態にコード変
換するもので、このコード変換器48で已−ド変換され
た信号は計算機5がらの信号により開閉動作するトライ
ステートバッファ49を介して計算機5に出力される。That is, the DTMF signal Is is introduced into a high group filter 43 and a low group filter 44 via an input amplifier 41 and a dial tone filter 42.
3.44, each frequency is determined. The judgment outputs of these filters 43 and 44 are led to a digital detection circuit 47 via zero/zero detectors 45 and 46, respectively. This digital detection circuit 47 identifies the frequency of the input DTMF signal by counting the period of the input signal for each high group and low group using a high speed clock, and supplies the identification output to the code converter 48 . The code converter 48 converts the identification output into a code suitable for the computer 5, and the signal converted by the code converter 48 is sent to a tri-state buffer 49 which opens and closes according to signals from the computer 5. is output to the computer 5 via.
尚、51は上記デジタル検出回路47およびコード変換
器48の動作を制御するステイーリング論理回路、52
はバイアス回路、53はクロック発生回路である。Note that 51 is a staying logic circuit that controls the operations of the digital detection circuit 47 and code converter 48;
53 is a bias circuit, and 53 is a clock generation circuit.
さて、この様なりTMF信号受信器4の前段には、この
DTMF信号受信器4とともに多周波信号受信装置を構
成するフィルタ回路6が設けである。このフィルタ回路
6は、例えば第3図に示す如く演算増幅器61を使用し
た二次のバターワース特性を持つアクティブ形の高域通
過フィルタからなるもので、しゃ断層波数fcは約80
0 H2に設定しである。第4図はそのろ波特性を示す
ものである。Now, as described above, a filter circuit 6 is provided upstream of the TMF signal receiver 4, which together with the DTMF signal receiver 4 constitutes a multi-frequency signal receiving apparatus. The filter circuit 6 is, for example, an active type high-pass filter having a second-order Butterworth characteristic using an operational amplifier 61 as shown in FIG. 3, and has a cutoff wave number fc of approximately 80.
It is set to 0H2. FIG. 4 shows its filtering characteristics.
このような構成であるから、伝送路2を介して到来した
DTMF信号は先ずフィルタ回路6に導入されてこのフ
ィルタ回路6で三次歪みの周波数成分が減衰されたのち
、DTMF信号受信器4に導かれてこの受信器4で先に
述べたように受信復↓化される。ここで、いま問題とな
っている押しボタンダイヤルキー゛″誉“のDTMF信
号に着目してみると、この押しボタンダイヤルキー“舛
“の低群周波数fs−−941−は上記フィルタ回路6
を通過することにより約1.88減衰するが、三次歪み
(2ft、−fu=673)h)はそれよりも太きく4
.9c13減衰し、この結果上記低群周波数fLの歪み
率は3.1dB改善される。すなわち、DTMF信号受
信器4の三次歪みに対する規格をDとすると、伝送路2
で発生する三次歪みが約D−3以下であれば押しボタン
ダイヤルキー“搏”の低群周波数の受信は可能となる。With such a configuration, the DTMF signal arriving via the transmission path 2 is first introduced into the filter circuit 6, where the frequency component of third-order distortion is attenuated, and then introduced into the DTMF signal receiver 4. The signal is then received and decoded by the receiver 4 as described above. Now, if we focus on the DTMF signal of the push-button dial key "Homare" which is currently in question, the low group frequency fs--941- of this push-button dial key "Masu" is the filter circuit 6.
is attenuated by approximately 1.88, but the third-order distortion (2 ft, -fu=673
.. As a result, the distortion rate of the low group frequency fL is improved by 3.1 dB. That is, if the standard for third-order distortion of the DTMF signal receiver 4 is D, then the transmission line 2
If the third-order distortion generated by the signal is approximately D-3 or less, it is possible to receive the low group frequency of the push button dial key "搏".
したがって、この低群周波数fLが他の押しボタンダイ
ヤルキーの低群周波数と誤判定される不具合は大幅に低
減される。またこのことは言替えると、DTMF受信器
4の三次歪みに対する規格を緩和できることに相当し、
これによりDTMF信号受信器4の設計条件および回路
構成を簡単化することができる。尚、上記フィルタ回路
6を挿入することにより、低群周波数が最も低く高群周
波数が最も高い押しボタンダイヤルキー“3”のDTM
F信号の低群周波数および高群周波数間の受信信号レベ
ル差の拡大が問題となることがあるが、この場合のフィ
ルタ回路6通過侵のDTMF信号のレベル差の拡大は4
.25dBであり、この程度の拡大はDTMF信号受信
器4の特性を十分に満足するものであり特に問題はない
。Therefore, the problem that this low group frequency fL is erroneously determined as the low group frequency of another push button dial key is greatly reduced. In other words, this corresponds to being able to relax the standards for third-order distortion of the DTMF receiver 4.
This allows the design conditions and circuit configuration of the DTMF signal receiver 4 to be simplified. By inserting the filter circuit 6, the DTM of the push button dial key "3" where the low group frequency is the lowest and the high group frequency is the highest.
The expansion of the received signal level difference between the low group frequency and the high group frequency of the F signal may become a problem, but in this case, the expansion of the level difference of the DTMF signal passing through the filter circuit 6 is 4.
.. This level of expansion satisfies the characteristics of the DTMF signal receiver 4 and poses no particular problem.
尚、本発明は上記実施例に限定されるものではない。例
えば、上記実施例では押しボタンダイヤルキー“舛“の
低群周波数の歪みを低減する場合について説明したが、
高群周波数の歪みが問題となる場合は、フィルタ回路に
しゃ断層波数がfc=1.2K)lx程度の低域通過フ
ィルタを用いればよい。また低群および高群の各三次歪
みを同時に低減する必要がある場合は、フィルタ回路と
して800 tb以上でかつ1.2にセ以下の周波数帯
域のみを通過させる帯域通過フィルタを使用すればよい
。ざらに、前記実施例ではフィルタ回路として、二次の
バターワース特性を持つアクティブ形のフィルタを使用
した場合について説明したが、抵抗およびコンデンサを
使用した一次のフィルタを使用してもよい。その他、多
周波信号の種類や多周波信号受信器の構成1、多周波信
号受信装置を適用するシステムの構成等についても、本
発明の要旨を逸脱しない範囲で種々変形して実施できる
。Note that the present invention is not limited to the above embodiments. For example, in the above embodiment, the case was explained in which the distortion of the low group frequency of the push button dial key "Masu" was reduced.
If distortion at high group frequencies is a problem, a low-pass filter with a cutoff wave number of approximately fc=1.2K)lx may be used in the filter circuit. Furthermore, if it is necessary to simultaneously reduce each third-order distortion of the low group and the high group, a band-pass filter that passes only the frequency band of 800 tb or more and 1.2 centigrade or less may be used as a filter circuit. Roughly speaking, in the above embodiment, a case has been described in which an active type filter having a second-order Butterworth characteristic is used as the filter circuit, but a first-order filter using a resistor and a capacitor may also be used. In addition, the types of multi-frequency signals, the structure of the multi-frequency signal receiver, the structure of the system to which the multi-frequency signal receiver is applied, etc. can be modified in various ways without departing from the gist of the present invention.
以上詳述したように本発明によれば、伝送路と多周波信
号を受信し復号化する回路との間にフィルタ回路を設け
、このフィルタ回路により伝送路で発生する多周波信号
の三次歪みのうち所定の周波数成分を減衰させて多周波
信号との信号レベル差を拡大するようにしたことによっ
て、三次歪みの影響を低減して正確な多周波信号の識別
を行ない得る多周波信号受信装置を提供することができ
る。As detailed above, according to the present invention, a filter circuit is provided between a transmission line and a circuit for receiving and decoding a multifrequency signal, and this filter circuit eliminates third-order distortion of the multifrequency signal generated on the transmission line. The present invention provides a multifrequency signal receiving device that can reduce the influence of third-order distortion and accurately identify multifrequency signals by attenuating predetermined frequency components and expanding the signal level difference between the multifrequency signal and the multifrequency signal. can be provided.
第1図乃至第4図は本発明の一実施例における多周波信
号受信装置を説明するためのもので、第1図は同装置を
適用した電話システムの概略構成図、第2図はDTMF
信号受信器の構成を示す回路ブロック図、第3図はフィ
ルタ回路の回路構成図、第4図は同回路のろ波特性を示
す図、第5図は従来のDTMF信号受信装置を適用した
電話システムの概略構成図、第6図は伝送路の構成の一
例を示す概略図である。
1.3・・・電話機、2・・・伝送路、21・・・無線
回線、22・・・送受信機、23・・・移動用交換局、
26・・・総括局、27・・・中心局、28・・・集中
局、29・・・端局、4・・・DTMF信号受信器、5
・・・計算機、41・・・入力増幅器、42・・・ダイ
ヤルトーンフィルタ、43・・・高群フィルタ、44・
・・低群フィルタ、45゜46・・・零クロス検出器、
47・・・デジタル検出回路、48・・・コード変換器
、49・・・トライステートバッフ7.51・・・ステ
イーリング論理回路、52・・・バイアス回路、53・
・・クロック発生回路、6・・・フィルタ回路。1 to 4 are for explaining a multi-frequency signal receiving device according to an embodiment of the present invention, FIG. 1 is a schematic configuration diagram of a telephone system to which the device is applied, and FIG. 2 is a DTMF
Figure 3 is a circuit block diagram showing the configuration of a signal receiver, Figure 3 is a circuit diagram of a filter circuit, Figure 4 is a diagram showing the filtering characteristics of the same circuit, Figure 5 is a diagram showing a conventional DTMF signal receiving device. FIG. 6 is a schematic diagram showing an example of the configuration of a transmission path. 1.3... Telephone, 2... Transmission line, 21... Radio line, 22... Transmitter/receiver, 23... Mobile switching center,
26... General station, 27... Central station, 28... Central station, 29... Terminal station, 4... DTMF signal receiver, 5
... Computer, 41 ... Input amplifier, 42 ... Dial tone filter, 43 ... High group filter, 44.
...Low group filter, 45°46...Zero cross detector,
47... Digital detection circuit, 48... Code converter, 49... Tri-state buffer 7.51... Staying logic circuit, 52... Bias circuit, 53...
... Clock generation circuit, 6... Filter circuit.
Claims (1)
復号化する多周波信号受信装置において、前記伝送路と
多周波信号を受信し復号化する回路との間に、伝送路で
発生する多周波信号の三次歪みのうち所定の周波数成分
を減衰させて多周波信号との信号レベル差を拡大するフ
ィルタ回路を設けたことを特徴とする多周波信号受信装
置。In a multi-frequency signal receiving device that receives and decodes a multi-frequency signal sent from a transmitting side via a transmission line, there is a gap between the transmission line and a circuit that receives and decodes the multi-frequency signal. What is claimed is: 1. A multi-frequency signal receiving device, comprising: a filter circuit that attenuates a predetermined frequency component of third-order distortion of the multi-frequency signal to increase a signal level difference between the multi-frequency signal and the multi-frequency signal.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP60067038A JPS61225994A (en) | 1985-03-30 | 1985-03-30 | Multi-frequency signal receiver |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP60067038A JPS61225994A (en) | 1985-03-30 | 1985-03-30 | Multi-frequency signal receiver |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS61225994A true JPS61225994A (en) | 1986-10-07 |
Family
ID=13333289
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP60067038A Pending JPS61225994A (en) | 1985-03-30 | 1985-03-30 | Multi-frequency signal receiver |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS61225994A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2006174473A (en) * | 2004-12-15 | 2006-06-29 | Microsoft Corp | Energy detection receiver for uwb |
-
1985
- 1985-03-30 JP JP60067038A patent/JPS61225994A/en active Pending
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2006174473A (en) * | 2004-12-15 | 2006-06-29 | Microsoft Corp | Energy detection receiver for uwb |
US8787470B2 (en) | 2004-12-15 | 2014-07-22 | Microsoft Corporation | Data encoding |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US4191855A (en) | Full duplex audio response device | |
JPH0730930A (en) | Dual tone detector allowing operation under presence of voice or background noise and its method | |
US5416802A (en) | Receiver circuit for digital and analog modulated signal | |
JPS61225994A (en) | Multi-frequency signal receiver | |
JPS60112357A (en) | Information transmission system | |
US6047036A (en) | System and method for implementing a mute voice signal upon reception of a ADPCM zero nibble in wireless communications | |
JPS62220054A (en) | Receiver for charging signal of central office line trunk circuit | |
US20020141568A1 (en) | Dual threshold correlator | |
JP2805555B2 (en) | Wireless communication device | |
JP2927565B2 (en) | Multi-frequency signal receiver | |
JPH06303161A (en) | If circuit | |
JPH05153021A (en) | Mobile communication system | |
JP2000244342A (en) | Transmission circuit | |
SU1690207A1 (en) | Device for control of busy channels of tonal frequency | |
JPH0846540A (en) | Noise signal detection circuit | |
JPS57171870A (en) | Signal deciding circuit for digital multifrequency signal receiver | |
JPH01212010A (en) | Squelch circuit with fast leading | |
JPS62144493A (en) | Multifrequency signal receiver | |
JPS61262394A (en) | Receiving system for multi-frequency signal | |
JPS5994955A (en) | Dial signal transmitting circuit | |
JPS6412134B2 (en) | ||
JPH04354495A (en) | Pb tone transmission system | |
JPS60172843A (en) | Control signal transmission system | |
KR20000052408A (en) | Digital quadrature discriminator for demodulation of frequency-modulated information | |
JPH07177112A (en) | Control signal receiver |