JPS62141823A - Data transmission method - Google Patents

Data transmission method

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Publication number
JPS62141823A
JPS62141823A JP28188685A JP28188685A JPS62141823A JP S62141823 A JPS62141823 A JP S62141823A JP 28188685 A JP28188685 A JP 28188685A JP 28188685 A JP28188685 A JP 28188685A JP S62141823 A JPS62141823 A JP S62141823A
Authority
JP
Japan
Prior art keywords
transmission
transmitting
amplification factor
level
data
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
Application number
JP28188685A
Other languages
Japanese (ja)
Inventor
Yasuo Tanaka
康夫 田中
Kenji Tsutsumi
堤　謙二
Ryoji Shimozono
下園　良二
Yasunori Ogawa
小川　保典
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.)
Fujitsu Ltd
Original Assignee
Fujitsu 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 Fujitsu Ltd filed Critical Fujitsu Ltd
Priority to JP28188685A priority Critical patent/JPS62141823A/en
Publication of JPS62141823A publication Critical patent/JPS62141823A/en
Pending legal-status Critical Current

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  • Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)

Abstract

PURPOSE:To keep an S/N characteristic in a good state by pairing the step of detection and that of transmission, and transmitting data from a transmitting part in the transmission level which is updated in proportion to the value of detected equalizing amplification factor. CONSTITUTION:Transmitting parts 24 and 26 consist of driving circuits DRV. Each of receiving parts 25 and 27 consists of an equalizing amplifying circuit EQL and a reception reproducing device RCV and is provided with a corresponding amplification factor control circuit GCC. After detecting the equalizing amplification factor, the circuit GCC updates the transmission level of the transmitting part. As the result, the transmission level is controlled adaptively by feedback from the receiving part. The equalizing amplifying circuit EQL incorporates a preliminarily determined reference level; and after the reception level reaches this reference level, if follows up the reference level while hunting.

Description

【発明の詳細な説明】 〔概　要〕 ２つの送受信ユニットが共通の伝送路を介して接続され
、データの授受を行う場合におけるいわゆるＳ／Ｎ特性
の改善を図る。」二記の送受信ユニットは各々、送信部
と受信部とを含むものであるが、両者の間には、送信レ
ベルおよび等化増幅率に関し関連を持たせることとする
。つまり、今受信したデータについて用いられた等化増
幅率の大きさを、これから送信しようとするデータの送
信レベルの設定に反映させる。DETAILED DESCRIPTION OF THE INVENTION [Summary] The present invention aims to improve so-called S/N characteristics when two transmitting/receiving units are connected via a common transmission path and exchange data. Each of the two transmitting/receiving units includes a transmitting section and a receiving section, and there is a relationship between the two in terms of transmission level and equalization amplification factor. That is, the magnitude of the equalization amplification factor used for the data just received is reflected in the setting of the transmission level of the data to be transmitted from now on.

〔産業上の利用分野〕[Industrial application field]

本発明はデータ伝送方法、特にＳ　／　Ｎ特性の改善を
意図したデータ伝送方法に関する。The present invention relates to a data transmission method, and particularly to a data transmission method intended to improve S/N characteristics.

従来から伝送システムにおけるＳ／Ｎ特性の改善は重要
事項の１つであり、種々の対策が講しられてきた。本発
明においては、白側および相手側の送受信ユニットが共
通の伝送路、例えはメタリック加入者線によって接１涜
される場合について言及する。この場合、伝送路の損失
を知るごとがＳ／Ｎ特性の改善の早道である。なぜなら
一般にノイズ（Ｎ）を常に定量的に把握することは不可
能だからである。Improvement of S/N characteristics in transmission systems has traditionally been an important issue, and various measures have been taken. In the present invention, reference will be made to the case where the transmitting/receiving units on the white side and the opposite side are connected by a common transmission line, for example, a metallic subscriber line. In this case, knowing the loss of the transmission path is the quickest way to improve the S/N characteristics. This is because it is generally impossible to always quantitatively understand noise (N).

ところが近年、背反しつつあるＩＳＵＮ（Ｉｎｔｅｇｒ
ａｔｅｄ　５ｅｒｖｉｃｅｓ　Ｄｉｇｉｔａｌ　Ｎｅｔ
ｗｏｒｋ）等では、その網構成は多種多様で伝送路の線
路長ならびに）員失は区々であり、１つ１つ損失を把握
するのは不可能である。そして、その網内では同一ケー
ブルに収容されるアナログ電話回線からのインパルス性
雑音がランダムにディジタルデータ回線に侵入し、Ｓ／
Ｎ特性からみたその回線品質の向上を一層困難なものと
している。However, in recent years, ISUN (Integr.
ated 5 services Digital Net
(work), etc., the network configurations vary widely, and the length of the transmission line and the loss of personnel vary widely, making it impossible to understand the loss one by one. Then, within that network, impulsive noise from analog telephone lines accommodated in the same cable randomly infiltrates the digital data line, causing S/
This makes it even more difficult to improve the line quality in terms of N characteristics.

〔従来の技術〕[Conventional technology]

第４図は一般的なデータ伝送システムの構成図である。 FIG. 4 is a block diagram of a general data transmission system.

本図において、１１は第１の送受信ユニット、１２は第
２の送受信ユニットであって、それぞれ局側および宅内
側に対応づけて考えるごとができる。両者間は単一の、
すなわち共通の伝送路１３で結ばれる。第１の送受信ユ
ニット１１は送信部１４と受信部１５からなり、第２の
送受信ユニット１２も又、送信部１６および受信部１７
からなる。各送受信部の伝送路１３に対する接続は、両
方向同時通信の場合、第１のハイブリッド回路（ＩＩＹ
ＢＩ）　　１７　　（エコーキャンセラー等を含む）お
よび第２ののハイブリッド回路（ｌＩＹＢ２）　　ｌ　
８（エコーキャンセラー等を含む）を介して行う。In this figure, 11 is a first transmitting/receiving unit, and 12 is a second transmitting/receiving unit, which can be thought of in association with the central office side and the residential side. There is a single
That is, they are connected by a common transmission path 13. The first transmitting/receiving unit 11 includes a transmitting section 14 and a receiving section 15, and the second transmitting/receiving unit 12 also includes a transmitting section 16 and a receiving section 17.
Consisting of In the case of simultaneous bidirectional communication, the connection of each transmitting/receiving unit to the transmission line 13 is connected to the first hybrid circuit (IIY
BI) 17 (including echo canceller etc.) and the second hybrid circuit (lIYB2) l
8 (including an echo canceller, etc.).

ここに、第１の送受信ユニット１１にて送信データＳＤ
Ｉおよび受信データＲＤＩの授受がなされ、同様に第２
の送受信ユニット１２においても送信データＳＤ２およ
び受信データＲＤ２の授受がなされる。Here, the first transmitting/receiving unit 11 transmits data SD
I and received data RDI are exchanged, and similarly the second
Transmission and reception unit 12 also exchanges transmission data SD2 and reception data RD2.

〔発明が解決しようとする問題点〕[Problem that the invention seeks to solve]

第４図に示す伝送システムでは送信データＳＤＩおよび
ＳＤ２の送信レベルは一定とし、各受信部１５．１７に
おいて等化増幅器により伝送路１３における損失を等化
している。したがって線路１員失の大きい伝送路１３が
用いられるときはその等化増幅率が大となり、結果とし
て、主信号の振幅に対する雑音（ノイズ）の振幅の比、
すなわち既述のＳ／Ｎ特性が劣化してしまう。これは雑
音に対する符号誤りのマージンを減少させるという問題
を生じさせる。一方、そのＳ／Ｎ特性の改善を狙ってむ
やみに送信レベルを筒くすることは、消費電力の増大を
招くのみならず、他回線への誘導障害を引起こすことに
なり重大な問題となる。In the transmission system shown in FIG. 4, the transmission level of the transmission data SDI and SD2 is kept constant, and the loss in the transmission line 13 is equalized by equalizing amplifiers in each receiving section 15, 17. Therefore, when a transmission line 13 with a large line member loss is used, its equalization amplification factor becomes large, and as a result, the ratio of the amplitude of noise to the amplitude of the main signal,
In other words, the S/N characteristics described above deteriorate. This creates the problem of reducing the code error margin to noise. On the other hand, unnecessarily increasing the transmission level with the aim of improving the S/N characteristic not only increases power consumption, but also causes problems with guidance to other lines, which is a serious problem. .

〔問題点を解決するための手段〕[Means for solving problems]

第１図は本発明に係るデータ伝送方法を実施するだめの
システム構成例を示す図である。なお、全図を通じて同
一の（ｊ４成要素には同一の参照番号又は記号を付して
示す。本発明に基づく第１および第２の送受信ユニット
２１および２２においては、各送受信ユニット（２１，
２２）内の送信部（２４，２６）と受信部（２５，２７
）との間に相互関連がもたせられている。この関連は第
１図において−１二向きの矢印でそれぞれ図解的に示さ
れている。つまり、従来は各送受信部間（２４と２５゜
２６と２７）は相互に全く独立であった。FIG. 1 is a diagram showing an example of a system configuration for implementing the data transmission method according to the present invention. Note that the same (j4 components are shown with the same reference numbers or symbols throughout the figures.) In the first and second transmitting/receiving units 21 and 22 according to the present invention,
22), the transmitting section (24, 26) and the receiving section (25, 27)
) are interrelated. This relationship is schematically shown in FIG. 1 by two -1 pointing arrows, respectively. In other words, conventionally, the transmitting and receiving sections (24 and 25 degrees, 26 and 27) were completely independent from each other.

具体的には、第１の送受信ユニット２１において、受信
部２５は受信したデータに対して所定の等化増幅率をも
って等化増幅を行うが、この等化増幅率をまず検出する
。そして検出された等化増幅率は送信部２４に帰還され
る（前記の上向き矢印）。さらに、帰還された等化増幅
率に基づき送信部２４は送信レベルを決定し、決定され
た送信レベルをもって送信データＳＤＩを伝送路１３に
送出する。この場合、等化増幅率の値の増減に対し比例
的に増減して送信レベルを更新させる。Specifically, in the first transmitting/receiving unit 21, the receiving section 25 performs equalization amplification on the received data with a predetermined equalization amplification factor, and this equalization amplification factor is first detected. The detected equalization amplification factor is then fed back to the transmitter 24 (the above-mentioned upward arrow). Furthermore, the transmitter 24 determines a transmission level based on the equalization amplification factor fed back, and sends the transmission data SDI to the transmission line 13 at the determined transmission level. In this case, the transmission level is updated by increasing or decreasing in proportion to the increase or decrease in the value of the equalization amplification factor.

上述した受信・検出のステップと送信のステップは対を
なし、これら対のステップは複数回繰り返し実行される
。これと同様の動作は第２の送受信ユニット２２側でも
同様になされる。The reception/detection step and the transmission step described above form a pair, and these paired steps are repeatedly executed multiple times. The same operation is performed on the second transmitting/receiving unit 22 side as well.

〔作　用〕[For production]

Ｓ／Ｎ特性改善といっても雑音（Ｎ）を予測することは
できない。そこでＳ／Ｎ比に関し、雑音と密接な関連を
有する伝送路の損失に着目する。Even if the S/N characteristic is improved, the noise (N) cannot be predicted. Therefore, regarding the S/N ratio, we will focus on transmission path loss, which is closely related to noise.

つまり、雑音が一定ならば、減衰量が大きくなればなる
程、Ｓ／Ｎ特性は劣化することに着目する。In other words, we will focus on the fact that if the noise is constant, the larger the amount of attenuation, the worse the S/N characteristic becomes.

そこで、まず減衰量を知り、減衰量が大きければ大きい
程送信レベルを高くするよう制御する。ここに減衰量は
受信部の等化増幅率を検出することによって知ることが
できる。送信ならびに受信のためのデータは同一の伝送
路上を転送されるものであるから、全受信したデータに
及ぼされた減衰量をそのまま補償するように送信データ
に加えてやれば、そしてその操作を繰り返せば、適正な
送信レベルに落ち着く。Therefore, first, the amount of attenuation is known, and control is performed so that the larger the amount of attenuation, the higher the transmission level. Here, the amount of attenuation can be found by detecting the equalization amplification factor of the receiving section. Since data for transmission and reception are transferred over the same transmission path, the attenuation applied to all received data can be added to the transmission data to compensate for it, and the operation can be repeated. If so, the transmission level will settle down to an appropriate level.

〔実施例〕〔Example〕

第２図は本発明に係るデータ伝送方法を実施するための
詳細例を示す図である。送信部２４および２６はそれぞ
れ駆動回路Ｄ　ＲＶ　（ＤｒｉｖｅｒＣｉｒｃｉｕｔ　
）からなる。又、受信部２５および２７はそれぞれ等化
増幅回路Ｅ　Ｑ　Ｌ　（ＸｆｖＡＧＣＥｑｕａｌｉｚｅ
ｒ　）と受信再生装置ＲＣＶ　（ＲｅｃｅｉｖｅｒＣｉ
ｒｃｉｕＬ　）　とからなり、さらに本発明のポイント
に対応する増幅率制御回路Ｇ　ＣＣ（Ｇａ１ｎ　Ｃｏｎ
ｔｒｏｌＣ４ｒｃｉｕｔ　）を備える。該回路ＧＣＣが
既述の等化増幅率を検出した上で、送信部の送信レベル
を更新する。結局、送信レベルが、受信部からの帰還に
よりアダプティブに制御されることになる。FIG. 2 is a diagram showing a detailed example for implementing the data transmission method according to the present invention. The transmitters 24 and 26 each include a drive circuit DRV (DriverCircuit
). Further, the receiving sections 25 and 27 each include an equalization amplifier circuit EQL (XfvAGCEqualize
r ) and the receiving and reproducing device RCV (ReceiverCi
rciuL), and further includes an amplification factor control circuit GCC (Ga1nCon) corresponding to the point of the present invention.
trolC4rcitu). After the circuit GCC detects the equalization amplification factor described above, it updates the transmission level of the transmitter. As a result, the transmission level is adaptively controlled by the feedback from the receiver.

等化増幅回路ＥＱＬは本来的に予め定めた参照レベル（
Ｒｅｆ）を内蔵しており、受信レベルがこの参照レベル
に到達するとその後はハンチングしながらこの参照レベ
ルに追従する。このような参照レベルに至るまでに等化
増幅率が逐次変化するものの従来はこれを送信部に反映
させることはしなかった。The equalization amplifier circuit EQL originally has a predetermined reference level (
Ref), and when the reception level reaches this reference level, it follows this reference level while hunting. Although the equalization amplification factor changes successively until it reaches such a reference level, conventionally this has not been reflected in the transmitter.

一つの動作例を掲げると、まず伝送路１３が長く、した
がって損失も大であったとする。このような伝送路は明
らかに雑音に対して弱く、何らかの補償を加えることに
なる。このような伝送路では、等化増幅率は大であり、
この等化増幅率に応じて比例的に送信レベルを高（して
データの送信をすることから、等測的にＳ／Ｎ特性を改
善する結果となる。結局、雑音そのものには手を加える
ことができないから、知ることのできる損失を手がかり
にして、Ｓ／Ｎ特性を改善する。つまり、相手側からの
データを見て当該損失を知り、これを白側に帰還して白
側送信データに関しＳ／Ｎ特性の改善を図る。全く同じ
ことを相手側の送受信ユニットでも行えば、システム全
体としてｓＺＮ比の良好な適正レベルに収束する。To give an example of operation, let us first assume that the transmission path 13 is long and therefore has a large loss. Such a transmission path is obviously susceptible to noise, and some compensation must be added. In such a transmission line, the equalization amplification factor is large,
Since data is transmitted by increasing the transmission level proportionally according to this equalization amplification factor, the S/N characteristic is improved isometrically.In the end, the noise itself is modified. Therefore, the S/N characteristic is improved by using the loss that can be known as a clue.In other words, the loss is known by looking at the data from the other party, and this is returned to the white side and transmitted data from the white side. If the same thing is done with the transmitter/receiver unit on the other side, the sZN ratio of the entire system will converge to an appropriate level.

第３図は第２図における送受信ユニットの動作を図解的
に示すレベルチャートである。縦軸は損失Ｌ　（ｄＢ）
であって、上側は第１の送受信ユニット２１（例えば局
側）、下側は第２の送受信ユニ７）２２　（例えば宅内
側）である。横軸は時間軸りであり、ユニット２１およ
び２２共に（、−ｊ。FIG. 3 is a level chart schematically showing the operation of the transmitting/receiving unit in FIG. The vertical axis is loss L (dB)
The upper side is the first transmitting/receiving unit 21 (for example, the central office side), and the lower side is the second transmitting/receiving unit 7) 22 (for example, inside the house). The horizontal axis is the time axis, and both units 21 and 22 (, -j.

−＋　ｔ２→・・・のごと（経過する。又、本図中５Ｇ
Ｏ−１゜５ＧＯ−２、３Ｇ１−１　、　５Ｇ１−２・・
・は送信レベルをそれぞれ示し、ＲＧＯ−１、ＲＧＯ−
２、ＲＧＩ−１。-+ t2 →... (elapsed. Also, 5G in this figure
O-1゜5GO-2, 3G1-1, 5G1-2...
・indicates the transmission level, RGO-1, RGO-
2, RGI-1.

ＲＧＩ−２・・・は等化増幅率をそれぞれ示す。RGI-2... each indicates an equalization amplification factor.

■　まず、送信レベル５ＧＯ−１（初朋値ＯｄＢとする
）をもってデータの送信を行う（時刻ｔ０より）。(1) First, data is transmitted at a transmission level of 5GO-1 (initial value OdB) (from time t0).

■　上記■のデータを受けて、期間１ｃの間、既述の参
照レベルに落ち着くまで（時刻１１）、等化増幅を行う
。(2) Upon receiving the data in (2) above, equalization amplification is performed during period 1c until it settles down to the previously mentioned reference level (time 11).

■　上記■で検出した等化増幅率に対して比例的に定ま
る送信レベルＳＧＯ−２をもってデータの送信を行う（
時刻１．より）。■ Data is transmitted at the transmission level SGO-2, which is determined proportionally to the equalization amplification factor detected in (■) above.
Time 1. Than).

■　上記■のデータを受けて期間１ｃの間参照レベルに
落ち着くまで（時刻Ｌ２）、等化増幅を行う。(2) Upon receiving the data in (2) above, equalization amplification is performed during period 1c until it settles down to the reference level (time L2).

■　上記■で検出した等化増幅率に対して比例的に定ま
る送信レベル５Ｇ１−１をもってデータの送信を行う（
時刻ｔ、！より）。■ Data is transmitted at a transmission level of 5G1-1, which is determined proportionally to the equalization amplification factor detected in (■) above.
Time t! Than).

以後、全く同様の動作を、図中の■−■−■−・・・の
順番で繰り返す。ごの間の送信レベルおよび等化増幅率
の変化は次式で示される。Thereafter, exactly the same operation is repeated in the order of ■-■-■-... in the figure. Changes in the transmission level and equalization amplification factor during each period are expressed by the following equation.

５Ｇ（ｎ＋１）　　１−５Ｇｎ−１←ａ　（ＲＧｎ　−
１−Ｇｏ）ＳＧ（ｎ＋１）−２＝ＳＧｎ　　２トα（Ｒ
Ｇｎ　　２　　Ｇｏ）ただし、Ｇｏは既述した、目標等
化増幅率、αは所定の係数で帰還（受信部−送信部）の
大きさく収束の早さ）を定めるものである。なお、上記
式に現れる“−１”、“−２”はそれぞれ第３図の“−
１”、“−２′と同じであり第１の送受信ユニソｌ−（
２１）側か、第２の送受信ユニット（２２）側かの区別
を示す。又、送信レベルの更新のタイミングは、等化増
幅率の収束判定時（同一レベルが１ｃ続いたとき）に行
われる。5G(n+1) 1-5Gn-1←a (RGn −
1-Go)SG(n+1)-2=SGn 2toα(R
Gn 2 Go) However, Go is the target equalization amplification factor as described above, and α is a predetermined coefficient that determines the size and speed of convergence of the feedback (receiving section - transmitting section). Note that "-1" and "-2" appearing in the above formula are respectively "-1" and "-2" in Figure 3.
1", "-2', and the first transmitter/receiver unisol l-(
21) side or the second transmitting/receiving unit (22) side. Further, the timing of updating the transmission level is performed at the time of determining the convergence of the equalization amplification factor (when the same level continues for 1 c).

上記の漸化式により、等化増幅率は目標等化増幅率に収
束し、送信レベルは（Ｌ−Ｇｏ）（Ｌは前述した当該伝
送路の損失）に収束する。According to the above recurrence formula, the equalization amplification factor converges to the target equalization amplification factor, and the transmission level converges to (L-Go) (L is the loss of the transmission path described above).

又、損失りが目標等化増幅率よりも小さい場合は、送信
レベルはＯｄＢのまま固定され、等化増幅回路ＥＱＬの
利得もしで収束する。なお、第３図の一連の動作は、各
呼（ｃａｌｌ）の発生ごとに、同！ｔＪＩ　確立の段階
で実行され且つ完了するのが望ましい。If the loss is smaller than the target equalization amplification factor, the transmission level is fixed at OdB and converges at the gain of the equalization amplifier circuit EQL. Note that the series of operations shown in FIG. 3 is the same for each call! Preferably performed and completed during the tJI establishment phase.

〔発明の効果〕〔Effect of the invention〕

以上説明したように本発明によれば、各伝送路の損失の
大小に対しアダプティブに送信レベルを変更でき、少な
くとも、今定められている目標等化増幅率のもとでのＳ
／Ｎ特性は良好な状態に保たれる。As explained above, according to the present invention, the transmission level can be adaptively changed depending on the magnitude of loss in each transmission path, and at least the S
/N characteristics are maintained in good condition.

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

第１図は本発明に係るデータ伝送方法を実施するだめの
システム構成例を示す図、 第２図は本発明に係るデータ伝送方法を実施するための
詳細例を示す図、 第３図は第２図における送受信ユニットの動作を図解的
に示すレベルチャート、 第４図は一般的なデータ伝送システムの構成図である。 １３・・・伝送路、 ２１・・・第１の送受信ユニット、 ２２・・・第２の送受信ユニット、 ２４．２６・・・送信部、 ２５．２７・・・受信部、 ＥＱＬｌ、　ＥＱＬ２・・・等化増幅回路、ＧＣＣＩ、
　ＧＣＣ２・・・増幅率制御回路。FIG. 1 is a diagram showing an example of a system configuration for implementing the data transmission method according to the present invention, FIG. 2 is a diagram showing a detailed example for implementing the data transmission method according to the present invention, and FIG. 2 is a level chart schematically showing the operation of the transmitting/receiving unit, and FIG. 4 is a configuration diagram of a general data transmission system. 13... Transmission path, 21... First transmitting/receiving unit, 22... Second transmitting/receiving unit, 24.26... Transmitting section, 25.27... Receiving section, EQLl, EQL2...・Equalization amplifier circuit, GCCI,
GCC2...Amplification factor control circuit.

Claims (1)

【特許請求の範囲】[Claims] １、各々が所定の送信レベルをもってデータを送信する
送信部と、受信したデータに対して所定の等化増幅率を
もって等化増幅を行う受信部とを具備する第１および第
２の送信ユニットと、該第１および第２の送受信ユニッ
トの間を接続する伝送路とを備え、前記第１および第２
の送受信ユニット間でデータの授受を行う伝送システム
において、前記第１および第２の送受信ユニットの前記
受信部において受信したデータについて用いられた等化
増幅率を検出する第１ステップと、検出された前記等化
増幅率の値に対し比例的に更新される前記送信レベルを
もって前記送信部よりデータの送信を行う第２ステップ
とを対にして、該対のステップが複数回繰り返し実行さ
れることを特徴とするデータ伝送方法。1. First and second transmitting units, each of which includes a transmitter that transmits data at a predetermined transmission level, and a receiver that performs equalization amplification on the received data with a predetermined equalization amplification factor; , a transmission path connecting between the first and second transmitting/receiving units;
In a transmission system for exchanging data between transmitting and receiving units, a first step of detecting an equalization amplification factor used for data received in the receiving section of the first and second transmitting and receiving units; A second step of transmitting data from the transmitter with the transmission level updated proportionally to the value of the equalization amplification factor is paired, and the paired steps are repeatedly executed a plurality of times. Characteristic data transmission method.
JP28188685A 1985-12-17 1985-12-17 Data transmission method Pending JPS62141823A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP28188685A JPS62141823A (en) 1985-12-17 1985-12-17 Data transmission method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP28188685A JPS62141823A (en) 1985-12-17 1985-12-17 Data transmission method

Publications (1)

Publication Number Publication Date
JPS62141823A true JPS62141823A (en) 1987-06-25

Family

ID=17645336

Family Applications (1)

Application Number Title Priority Date Filing Date
JP28188685A Pending JPS62141823A (en) 1985-12-17 1985-12-17 Data transmission method

Country Status (1)

Country Link
JP (1) JPS62141823A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0793292A1 (en) * 1996-02-28 1997-09-03 Nortel Networks Corporation An antenna receive calibration arrangement
JP2003511978A (en) * 1999-10-07 2003-03-25 アドバンスト・マイクロ・ディバイシズ・インコーポレイテッド Automatic output drive level control in home networked transceivers

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0793292A1 (en) * 1996-02-28 1997-09-03 Nortel Networks Corporation An antenna receive calibration arrangement
JP2003511978A (en) * 1999-10-07 2003-03-25 アドバンスト・マイクロ・ディバイシズ・インコーポレイテッド Automatic output drive level control in home networked transceivers
JP4636763B2 (en) * 1999-10-07 2011-02-23 アドバンスト・マイクロ・ディバイシズ・インコーポレイテッド Automatic output drive level control in home networked transceivers

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