JPS5836857B2 - Analog facsimile line automatic equalizer - Google Patents
Analog facsimile line automatic equalizerInfo
- Publication number
- JPS5836857B2 JPS5836857B2 JP53128595A JP12859578A JPS5836857B2 JP S5836857 B2 JPS5836857 B2 JP S5836857B2 JP 53128595 A JP53128595 A JP 53128595A JP 12859578 A JP12859578 A JP 12859578A JP S5836857 B2 JPS5836857 B2 JP S5836857B2
- Authority
- JP
- Japan
- Prior art keywords
- line
- equalizer
- equalizers
- analog facsimile
- control 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
Links
Landscapes
- Facsimile Transmission Control (AREA)
- Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
Description
【発明の詳細な説明】
本発明は、アナログファクシミリにおける回線自動等化
装置に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic line equalization device for analog facsimile.
アナログファクシミリでは、回線品質がそのままコピー
品質に影響し、回線品質が悪いと画質が劣化する。In analog facsimile, the line quality directly affects the copy quality, and if the line quality is poor, the image quality will deteriorate.
これは、送信側から受信側に画信号を伝送する際に、画
信号が、主として周波数によって回線伝搬時間が異なる
ために生じる群遅延歪、及び、周波数によって回線利得
が異なるために生じる減衰歪等の回線の伝送歪を受ける
ためである。This is due to group delay distortion, which occurs when the image signal is transmitted from the transmitting side to the receiving side, mainly because the line propagation time differs depending on the frequency, and attenuation distortion, which occurs because the line gain varies depending on the frequency. This is because the line is subject to transmission distortion.
このような回線の伝送歪を補正するためには、受信側に
等化器を設けて画信号の等化を行う必要がある。In order to correct such line transmission distortion, it is necessary to provide an equalizer on the receiving side to equalize the image signal.
ところで、一般にファクシミリはネットで使用され、送
信先或いは受信先に応じて異なる電話回線が使用される
ため、その時々で回線の伝送特性が異なってくる。Incidentally, facsimiles are generally used over the Internet, and different telephone lines are used depending on the destination or destination, so the transmission characteristics of the lines differ from time to time.
デイジタル伝送の場合は、送られてくる基準パルスに合
わせて、そのエラレートが最小になるように時間巾を自
動的に調整する自動等化が可能であるため、交信毎の回
線の伝送特性が異なっていても回線の伝送歪は簡単に補
正できる。In the case of digital transmission, automatic equalization is possible that automatically adjusts the time width to minimize the error rate according to the reference pulse being sent, so the transmission characteristics of the line differ for each communication. However, transmission distortion in the line can be easily corrected.
しかし、アナログ信号伝送の場合には、画信号が時間的
にサンプリングされていないため、自動等化が困難とな
る。However, in the case of analog signal transmission, automatic equalization becomes difficult because the image signal is not temporally sampled.
このため、従来のアナログファクシミリでは、各使用回
線の平均的伝送特性に合せて等化器を構或し、この固定
等化器によって回線の伝送歪の補正を行っていたが、使
用する回線によって、その伝送特性にかなりのばらつき
があるため、満足出来る結果が得られなかった。For this reason, in conventional analog facsimiles, equalizers were configured to match the average transmission characteristics of each line used, and the transmission distortion of the line was corrected using this fixed equalizer, but depending on the line used, However, due to considerable variation in the transmission characteristics, satisfactory results could not be obtained.
本発明は、上記の点に鑑みなされたものであって、簡単
な構或で、使用回線の伝送特性が異なっても、回線の伝
送歪かほゾ完全に自動的に補正されるアナログファクシ
ミリの回線自動等化装置を提供することを目的とする。The present invention has been made in view of the above points, and is an analog facsimile line that has a simple structure and can completely and automatically correct transmission distortion of the line even if the transmission characteristics of the line used are different. The purpose is to provide an automatic equalization device.
この目的を達成するために、本発明はアナログ画信号の
送受を行う以前に、先ず機械同志の信号の送受を行うの
で、このとき送信側から送られてくる基準信号が、回線
の伝送特性に対応したリツプル数を有する波形になるこ
とに着目し、そのリツプル数を検出することにより、自
動的に受信側等化器が、そのときの回線の伝送特性に対
応する特性になるように構成．したことを特徴とする。In order to achieve this objective, the present invention first transmits and receives signals between machines before transmitting and receiving analog image signals, so that the reference signal sent from the transmitting side at this time depends on the transmission characteristics of the line. Focusing on the fact that the waveform has a corresponding number of ripples, by detecting that number of ripples, the receiving equalizer is automatically configured to have characteristics that correspond to the transmission characteristics of the line at that time. It is characterized by what it did.
以下、本発明の一実施例を第１図乃至第３図を参照して
説明する。An embodiment of the present invention will be described below with reference to FIGS. 1 to 3.
第１図は、本発明の一実施例を示す自動等化装置のブロ
ック構戒図である。FIG. 1 is a block diagram of an automatic equalization device showing one embodiment of the present invention.
Ｅは１リンク分の回線の伝送歪を補正する等化器で、複
数個（本実施例の場合には３個）直列に接続されている
。E is an equalizer for correcting transmission distortion of a line for one link, and a plurality of equalizers (three in the case of this embodiment) are connected in series.
各等化器Ｅには並列に選択制御回路Ｃの出力に応じて開
く常閉制御接点Ｂが設けられ、等化器バイパス回路が形
成されている。Each equalizer E is provided in parallel with a normally closed control contact B that opens in response to the output of the selection control circuit C, forming an equalizer bypass circuit.
Ｄは復調器、Ｐはリツプル数検出器、Ｃはリツプル数検
出器Ｐから検出されるリツプル数に応じて所定数の接点
Ｂを開く選択制御回路である。D is a demodulator, P is a ripple number detector, and C is a selection control circuit that opens a predetermined number of contacts B in accordance with the number of ripples detected from the ripple number detector P.
アナログファクシミリでは、画信号の送受を行う以前に
、先ず接続可能か否か機械同志の信号の送受が行われる
。In an analog facsimile, before sending and receiving image signals, signals are first sent and received between machines to determine whether connection is possible.
このとき、送信側から受信側に第２図ａに示す基準信号
が送出される。At this time, the reference signal shown in FIG. 2a is sent from the transmitting side to the receiving side.
この基準信号は電話回線の群遅延歪、減衰歪等を受け、
復調器から取り出すと第２図ｂに示すように、リツプル
分を含んだ波形となる。This reference signal is subjected to group delay distortion, attenuation distortion, etc. of the telephone line,
When taken out from the demodulator, it becomes a waveform containing ripples as shown in FIG. 2b.
このリツプル分の平均レベルは、回線の歪特性、特に群
遅延時間に関係する。The average level of this ripple is related to line distortion characteristics, especially group delay time.
そして、この群遅延時間は回線中に含まれている接続リ
ンクの数に関係し、実用上はほぼリンクの数に比例して
増大すると考えてよいから、結局、上記リツプル分の平
均レベルは回線に含まれた接続リンクの数にほぼ比例し
たものとなる。This group delay time is related to the number of connection links included in the line, and in practice it can be considered that it increases almost in proportion to the number of links, so in the end, the average level of the ripples mentioned above is It is approximately proportional to the number of connection links included in the .
一方、このリツプル分は減衰振動波形を呈することから
、その中に含まれるリツプルの数はその平均レベルにほ
ぼ比例したものとなり、従って、このリツプル分は、回
線中に含まれた接続リンクの数に関係し、リンク数に比
例して増減する。On the other hand, since this ripple component exhibits a damped oscillation waveform, the number of ripples included in it is approximately proportional to its average level. Therefore, this ripple component is the number of connecting links included in the line. , and increases or decreases in proportion to the number of links.
これをリツプル数検出器Ｐで、あらかじめ設定されたス
レショールドレベルと比較してリツプル数を取り出す。A ripple number detector P compares this with a preset threshold level and extracts the number of ripples.
このときのスレショールドレベルは、回線シュミレータ
を介して実験を行い、回線の接続リンク数に応じて所定
のリツプル数が得られるように設定する。The threshold level at this time is set through experiments using a line simulator so that a predetermined number of ripples can be obtained depending on the number of connected links of the line.
従って、このリツプル数を調べれば、回線の接続リンク
数が分るので、その数に対応する数の等化器を介して受
信信号を復調器に取り出せば良い。Therefore, by checking this number of ripples, the number of connected links of the line can be determined, and the received signal can be extracted to the demodulator through equalizers corresponding to that number.
このため、選択制御回路Ｃはこのリツプル数に対応して
所定数の接点Ｂを開く。Therefore, the selection control circuit C opens a predetermined number of contacts B corresponding to this number of ripples.
この結果、受信信号は回線の接続リンク数に相当する数
の等化器Ｅを経て復調器Ｄに取り出され、回線の伝送歪
が補正される。As a result, the received signal is taken out to the demodulator D through equalizers E in a number corresponding to the number of links connected to the line, and transmission distortion of the line is corrected.
例えば、第３図の実験波形で示すように、送信側からａ
に示す基準信号波形を送出し、これを１リンク乃至３リ
ンクの回線シュミレータを介して復調器から取り出した
ところｂ乃至ｄに示す波形が得られた。For example, as shown in the experimental waveform in Figure 3, a
When the reference signal waveforms shown in Fig. 1 were sent out and taken out from the demodulator via the 1-link to 3-link line simulators, the waveforms shown in b to d were obtained.
そこで、１リンク分の伝送歪の補正に必要な特性をもっ
た同一特性の等化器を複数個用意し、これを１ １Ｊン
クの場合には１個、２リンクの場合はその等化器を２個
、３リンクの場合はその等化器を３個直列に接続して復
調器から受信信号を取り出したところ、夫々ｅ乃至ｇに
示すように基準信号波形にほぼ等しい波形が得られた。Therefore, we prepare multiple equalizers with the same characteristics that have the characteristics necessary to correct transmission distortion for one link. When two or three equalizers were connected in series and the received signal was extracted from the demodulator, waveforms approximately equal to the reference signal waveforms were obtained, as shown in e to g, respectively. .
尚、上記実施例ではｌリンク分の回線歪を補正する等化
器を３個用いて回線自動等化装置を構威したが等化器の
個数は、補正しようとする回線特性の数に応じ任意数に
設けることは云う迄もない。In the above embodiment, an automatic line equalization device was constructed using three equalizers for correcting line distortion for one link, but the number of equalizers may vary depending on the number of line characteristics to be corrected. Needless to say, any number of them can be provided.
また、上記実施例では、１リンク分の回線の伝送歪を補
正する等化器Ｅを複数個設けて回線自動等化装置を構成
したが、使用する回線特性に対応する等化器を夫々用意
しておき、得られる受信波形に含まれるリツプル数によ
って所定の特性の等化器を選択するように構威しても良
い。In addition, in the above embodiment, the line automatic equalization device is configured by providing a plurality of equalizers E for correcting line transmission distortion for one link, but each equalizer is prepared in accordance with the line characteristics to be used. Then, an equalizer with predetermined characteristics may be selected depending on the number of ripples included in the received waveform obtained.
以上の記載の通り、本発明によれば、送信側から送られ
てくる基準信号が、回線の伝送特性に対応したリツプル
数を有する波形になることに着目し、そのリツプル数を
検出することにより、受信側等化器が自動的にそのとき
の回線の伝送特性に対応する特性になるように構威した
ので、簡単な構戒で、その時々で、使用回線の伝送特性
が異なっても、常にアナログ画信号の回線の伝送歪は補
正され、コピー品質が改善される。As described above, according to the present invention, by focusing on the fact that the reference signal sent from the transmitting side has a waveform having a number of ripples corresponding to the transmission characteristics of the line, and detecting the number of ripples, , the equalizer on the receiving side is configured to automatically set the characteristics to match the transmission characteristics of the line at that time, so with simple precautions, even if the transmission characteristics of the line used differ from time to time, Transmission distortion of analog image signal lines is always corrected, and copy quality is improved.
第１図は、本発明の一実施例を示すアナログファクシミ
リの回線自動等化装置のブロック構成図、第２図ａ，ｂ
は、送信側から送出される基準波形及び回線を経て受信
側復調器から取り出される受信波形を示す波形図、第３
図は各実験波形を示したもので、そのａは送信側から送
出される基準波形図、ｂ−ｄは各回線シュミレータを介
して得られる等化器を通す前の受信波形図、ｅ ”’−
ｇは各等化器を通した後の受信波形図である。
Ｅ・・・・・・等化器、Ｄ・・・・・・復調器、Ｐ・・
・・・・リツプル数検出器、Ｂ・・・・・・制御接点、
Ｃ・・・・・・選択制御回路。FIG. 1 is a block diagram of an automatic line equalization device for an analog facsimile machine showing an embodiment of the present invention, and FIG. 2 a, b
3 is a waveform diagram showing the reference waveform sent from the transmitting side and the received waveform taken out from the receiving side demodulator via the line.
The figure shows each experimental waveform, in which a is a reference waveform diagram sent from the transmitting side, b-d are received waveform diagrams obtained through each line simulator before passing through an equalizer, and e ''' −
g is a received waveform diagram after passing through each equalizer. E: Equalizer, D: Demodulator, P:
... Ripple number detector, B ... Control contact,
C...Selection control circuit.
Claims (1)
と、送信側から送出される基準信号を受信し、その受信
波形に含まれるリツプル数を検出するリツプル数検出器
と、該リツプル数検出器からの検出値に応じて、上記等
化器を選択する選択制御回路とから成ることを特徴とす
るアナログファクシミリの回線自動等化装置。 ２ 特許請求の範囲第１項記載において、前記等化器は
、同一特性に構成されており、前記選択制御回路は、前
記検出値に応じて上記等化器を所定数選択するように構
成されていることを特徴とするアナログファクシミリの
回線自動等化装置。 ３ 特許請求の範囲第１項記載において、前記等化器は
、各回線に対応して各所定の特性に構成されており、前
記選択制御回路は、前記検出値に応じて上記等化器の所
定のものを選択するように構成されていることを特徴と
するアナログファクシミリの回線自動等化装置。[Claims] 1. A plurality of equalizers that correct transmission distortion of a line for one link, and a ripple number that receives a reference signal sent from the transmitting side and detects the number of ripples included in the received waveform. An automatic line equalization device for an analog facsimile machine, comprising a detector and a selection control circuit that selects the equalizer according to the detected value from the ripple number detector. 2. In claim 1, the equalizers are configured to have the same characteristics, and the selection control circuit is configured to select a predetermined number of the equalizers according to the detected value. An analog facsimile automatic line equalizer characterized by: 3. In claim 1, the equalizer is configured to have predetermined characteristics corresponding to each line, and the selection control circuit controls the equalizer according to the detected value. An automatic line equalizer for an analog facsimile, characterized in that it is configured to select a predetermined value.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP53128595A JPS5836857B2 (en) | 1978-10-20 | 1978-10-20 | Analog facsimile line automatic equalizer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP53128595A JPS5836857B2 (en) | 1978-10-20 | 1978-10-20 | Analog facsimile line automatic equalizer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5555669A JPS5555669A (en) | 1980-04-23 |
| JPS5836857B2 true JPS5836857B2 (en) | 1983-08-12 |
Family
ID=14988642
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP53128595A Expired JPS5836857B2 (en) | 1978-10-20 | 1978-10-20 | Analog facsimile line automatic equalizer |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5836857B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH054929U (en) * | 1991-07-03 | 1993-01-26 | 積水化学工業株式会社 | sink |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH03160876A (en) * | 1989-11-20 | 1991-07-10 | Ricoh Co Ltd | Control method for facsimile equipment |
-
1978
- 1978-10-20 JP JP53128595A patent/JPS5836857B2/en not_active Expired
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH054929U (en) * | 1991-07-03 | 1993-01-26 | 積水化学工業株式会社 | sink |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5555669A (en) | 1980-04-23 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| DE69838906T2 (en) | Method and device for detecting and preventing message collisions in a communication system | |
| US4688245A (en) | Method and circuit arrangement for compensating cross-talk and/or echo signals | |
| JPS6211326A (en) | Resetting system for automatic equalizer | |
| EP0592747B1 (en) | Adaptive equalizing apparatus and method for token ring transmission systems using unshielded twisted pair cables | |
| US4500999A (en) | Line equalizer | |
| JPS5836857B2 (en) | Analog facsimile line automatic equalizer | |
| JP2986735B2 (en) | Modem device | |
| JP2557552Y2 (en) | Facsimile cable equalizer automatic switching device | |
| JPS6336620A (en) | Facsimile transmission system | |
| JP2662032B2 (en) | Communication method using modem | |
| US1653738A (en) | Suppression of echoes and singing in four-wire circuits | |
| JPH0222566B2 (en) | ||
| JPH06120774A (en) | Data reception equipment | |
| JPS596631A (en) | Device for compensating line characteristic | |
| JPS6376628A (en) | Semi-fixed equalizer | |
| JPS5926143B2 (en) | Optimal equalizer | |
| JPH0136284B2 (en) | ||
| KR930002687B1 (en) | Fax | |
| JPH0695653B2 (en) | Echo compensator | |
| JP2695464B2 (en) | Diversity receiver | |
| JPS6219097B2 (en) | ||
| JPS6020645A (en) | Automatic equalizing system | |
| JPS631781B2 (en) | ||
| JPH0212063B2 (en) | ||
| JPH0550168B2 (en) |