JPS6062255A - Time-division multiplex transmission system - Google Patents
Time-division multiplex transmission systemInfo
- Publication number
- JPS6062255A JPS6062255A JP16984783A JP16984783A JPS6062255A JP S6062255 A JPS6062255 A JP S6062255A JP 16984783 A JP16984783 A JP 16984783A JP 16984783 A JP16984783 A JP 16984783A JP S6062255 A JPS6062255 A JP S6062255A
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- JP
- Japan
- Prior art keywords
- signal
- terminal
- collision
- data
- transmission
- 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
- 230000005540 biological transmission Effects 0.000 title claims abstract description 44
- 230000005236 sound signal Effects 0.000 claims description 4
- 238000006243 chemical reaction Methods 0.000 claims 2
- 238000001514 detection method Methods 0.000 claims 2
- 230000008929 regeneration Effects 0.000 abstract 1
- 238000011069 regeneration method Methods 0.000 abstract 1
- 238000010586 diagram Methods 0.000 description 7
- 230000008054 signal transmission Effects 0.000 description 3
- 239000002253 acid Substances 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L12/00—Data switching networks
- H04L12/28—Data switching networks characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks]
- H04L12/40—Bus networks
- H04L12/407—Bus networks with decentralised control
- H04L12/413—Bus networks with decentralised control with random access, e.g. carrier-sense multiple-access with collision detection [CSMA-CD]
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- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Time-Division Multiplex Systems (AREA)
- Small-Scale Networks (AREA)
Abstract
Description
【発明の詳細な説明】
〔技術分野〕
本発明は、搬送波信号を用いた時分割多重伝送システム
に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a time division multiplex transmission system using carrier signals.
第１図はネットワークシステムのｔデル図を示すもので
あり、図中（２＋）（２゜）・・・は端末器で、これら
複数の端末器（２、）（２ｔ）川が１本の信号線ｆｌ）
に接続されている。このシステム内においては任意の２
つの端末器（２１） （２□）あるいは（２１）（２３
）間で情報伝送が可能である。情報伝送はシリアルデー
タとして時分割伝送される。データ伝送は搬送波信号式
とし、ＦＳＫ （Ｆｒｅｑｕｅｎｃｙ ５ｈｉｆｔ Ｋ
ｅｙｉｎｇ）変調が用いられる。Ｆ Ｓ ｒ＜変調とは
、近接する２つの周波数ｆ、とｆ。を用い、データ「１
」の部分はｆｌとし、データｒＯＪＯ時けｆ。の信号と
して送信することによって、２値論理音信号たるデジタ
ルデータの伝送を行なう。ところで、各端末器（２，）
は信号伝送が必要になった時点で、信号線（１）上に他
の端末器（２２）・・からの信号が伝送されていないか
どうかを確認し、信号がある場合はその信号の伝送が終
了するのを待ち、その後で送信を開始する。第２図はそ
の例を示し、端末器（２２）は、端末器（２１）のイハ
号終了後ｔ（１，の時間だけ遅れて信号送信を開始する
。このような手順を踏むことによって複数局からのイｉ
号が重々ることはない。しかし、複数局が同時に送信を
開始する場合には信号の衝突が生じる。従って、この場
合には受信側の端末器（２□）では正しい端末器（２゜
）からの信号・を受信できないことにガる。Figure 1 shows a t-Del diagram of a network system. In the figure, (2+) (2°)... are terminal devices, and these multiple terminal devices (2,) (2t) are connected to one river. signal line fl)
It is connected to the. Within this system, any 2
two terminals (21) (2□) or (21) (23
) can transmit information between them. Information transmission is time-divisionally transmitted as serial data. Data transmission is by carrier wave signal type, FSK (Frequency 5hift K
eyeing) modulation is used. F S r<modulation means two adjacent frequencies f, and f. using the data “1
” is fl, and the data rOJO is f. By transmitting it as a signal, digital data, which is a binary logic tone signal, is transmitted. By the way, each terminal (2,)
When it becomes necessary to transmit a signal, check whether a signal from another terminal (22) is being transmitted on the signal line (1), and if there is a signal, transmit that signal. wait for it to finish, then start sending. FIG. 2 shows an example of this, in which the terminal device (22) starts signal transmission after a delay of t(1,) after the terminal device (21) finishes the IHA signal. Ii from the station
The number is not heavy. However, when multiple stations start transmitting at the same time, signal collision occurs. Therefore, in this case, the terminal device (2□) on the receiving side cannot receive the signal from the correct terminal device (2°).
第８図は端末器（２）と信号線（１）の接続部分を示し
たものであわ、（４）は端末ロジック部で、この端末ロ
ジック部（４）はデータ伝送に必要なマイクロコンピュ
ータなどから構成されている。（３）は信号線（１）と
端末ロジック部（４）との間に挿入されて両者間におけ
る信号の授受を行なうモデムで、このモデム（３）は自
局の端末器（２）の端末ロジック部（４）からの２値論
理音信号からなる送信データをＦＭ変調して搬送波信号
に変換し、信号線（１）上に該搬送波信号を伝送するよ
うにしたり、また、反対に信号線（１）上の他の端末器
（２）からの搬送波信号を復調して２値論ｆＪｓ信鍔に
変換し、ロジックデータとして受信データを端末ロジッ
ク部（４）へ出力する。ところで、送信時に送信データ
は「１」あるいは「０」の２音信号であるため送信の必
要がない時にも周波数ｆ、かｆｏの搬送信号が送信され
てしまう。そこで、端末０シック部（４）よりモデム（
３）へゲート信号を送り、このゲート信号がアクティブ
の時のみ搬送波信号がモデム（３）より信号線（１）に
出力されるように制御している。そして、送信データに
応じて搬送波信号の周波数がｆ＋、ｆｏに変化する。モ
デム（３）から端末ロジック部（４）への信号のうち、
＋セリア信号はイ―帰線ｍ上に搬送波信号が存在するこ
とを示すＨ１ッペル信号であり、受信データは、搬送波
信号の周波数ｆ、の受信時は「１」であり、周波数ｆ。Figure 8 shows the connection between the terminal device (2) and the signal line (1). (4) is the terminal logic section, and this terminal logic section (4) includes a microcomputer etc. necessary for data transmission. It consists of (3) is a modem inserted between the signal line (1) and the terminal logic section (4) to send and receive signals between the two, and this modem (3) is the terminal of the terminal device (2) of the own station. Transmission data consisting of a binary logic tone signal from the logic section (4) is FM modulated and converted into a carrier wave signal, and the carrier wave signal is transmitted on the signal line (1), or conversely, the signal line (1) Demodulates the carrier signal from the other terminal (2) above, converts it into a binary fJs signal, and outputs the received data as logic data to the terminal logic section (4). By the way, since the transmitted data is a two-tone signal of "1" or "0" at the time of transmission, a carrier signal of frequency f or fo is transmitted even when there is no need for transmission. Therefore, the modem (
A gate signal is sent to the modem (3), and the carrier signal is controlled to be output from the modem (3) to the signal line (1) only when this gate signal is active. Then, the frequency of the carrier signal changes to f+ and fo in accordance with the transmitted data. Of the signals from the modem (3) to the terminal logic section (4),
The +Seria signal is an H1 Ppel signal indicating that a carrier signal exists on the E-retrace line m, and the received data is "1" when the carrier signal frequency f is received;
の受信時はｒＯＪである。衝突信号は信号線（１）上に
搬送波信号があるにもかかわらず、受信データが「Ｉ」
とも「０．１とも判定がつか々い場合にモデム（３）か
ら端末ロジック部（４）へ出力される。When receiving , it is rOJ. The collision signal is that the received data is "I" even though there is a carrier signal on the signal line (1).
``0.1'' is output from the modem (3) to the terminal logic unit (4) when the determination is difficult.
そして、送信中の端末器（２）における端末ロジック部
（４）では、ｐｔＪ記衝突信号がモデム（３）から入力
さね、ると、送信を即時停止するようにし、一定時間１
１ ｄ ２待った後、再度送信を開始する。尚、この時
１１．１ ｔｄｚは定数ではなく、乱数要素を持たせる
ことにより、例えば端末器（２１）あるいは端末器（２
゜）のどちらかが早く伝送を開始するようにする。この
様子は第４図に示す通りであり、両端末器（２＋）（２
゜）より搬送波信号が信号線（］）上に時分割伝送する
と、各搬送波信号が衝突し、各端末器（２＋０２２）で
衝突信号を検出し、信号の伝送を即時停止する。Then, in the terminal logic unit (4) of the terminal device (2) during transmission, if the ptJ collision signal is not input from the modem (3), the transmission is immediately stopped, and the transmission is stopped for a certain period of time.
After waiting 1 d 2, start sending again. At this time, 11.1 tdz is not a constant, but by having a random number element, it can be set to, for example, the terminal device (21) or the terminal device (2
゜) so that either one of them starts transmission earlier. This situation is shown in Figure 4, where both terminals (2+) (2
When the carrier wave signals are time-divisionally transmitted from ゜) to the signal line (]), each carrier wave signal collides, and each terminal device (2+022) detects the collision signal and immediately stops the signal transmission.
そして、端末器（２，）よりも短い一定の時間ｔｄ２に
端末器（２１）が信号を送信し、端末器（２、）の送信
終了後、一定の時間ｔｄ、経過後に端末器（２□）が信
号の伝送を開始することになる。このように、以上説明
した方法を用いて搬送波信号の衝突が発生する場合も、
各端末器（２）が順に伝送することができるものである
。しかしながら、端末器（２）の数が多く、かつ時間ｔ
ｄ２の乱数の範囲が広くとれない場合、２台以上の端末
器（２）のｔｄ２が同一となり、再度衝突が発生し、正
しい信号伝送が終了するまで多くの時間を要するという
問題があった。Then, the terminal (21) transmits a signal at a fixed time td2, which is shorter than the terminal (2,), and after a fixed time td has passed after the terminal (2,) finishes transmitting, the terminal (2,) ) will start transmitting the signal. In this way, even when carrier signal collision occurs using the method explained above,
Each terminal (2) can transmit data in turn. However, the number of terminal devices (2) is large and the time t
If the random number range of d2 is not wide enough, two or more terminals (2) will have the same td2, causing a collision again, and it will take a long time to complete correct signal transmission.
本発明は上述の点に鑑みて提供したものであって、端末
器の数が多い場合の搬送波信号の再度の衝突回数を減ら
すことを目的とした時分割多重伝送システムを提供する
ものである。The present invention has been provided in view of the above-mentioned points, and provides a time division multiplex transmission system for the purpose of reducing the number of times carrier signals collide again when there are a large number of terminals.
〔発明の開示］ 以下、本発明の実施例を図面により詳述する。[Disclosure of invention] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
第５図は具体回路図を示し、モデム（３）、端末０．；
ツク部（４）は従来と同様であり、モデム（：１）から
の受信データ出力と、衝突信号をインバータＧ２で反転
［７だ信号とをアシドゲートＧ１で論理積をとり、アン
ドケートＧ、の出力を端末０シック部（４）への受信デ
ータ入力としている。そして、アンドゲートＧ１の出力
と、端末０シック部（４）からの送信データとを１！：
Ｘ −ＯＲゲートＧ、で排他的論理和を行ない、そのＥ
Ｘ −ＯＲゲート（］、の出力と、モデム（３）からの
１１７リア信号とでアンドゲートＧ、で論理積をとり、
このアクトゲートＧ、の出力を衝突信号として端末ロジ
ック部（４）へ入力し７ている。上記各ゲート６１〜に
、にて衝突処３３０手段が構成される。これによって、
データ「１１とデータ「０」が衝突し、Ｆ Ｍ復調した
搬送波信号がデータ「１」、［０］のいずれか判断がつ
かない場合、ｔ−ｒ’ム（３）からのＨレベルの衝突信
号はインバータＧ２によってＬレベルになり、そのため
、アンドゲートＧ１の出力はＬレベルとなるため、端末
ロジック部（４）における受信データ入力は必ず［０−
１となる。この時、端末ロジック部（４）から送信デー
タ「０」を送信している場合には、ＥＸ −ＯＲゲート
Ｇ、の出力はＬレベルとなるために、衝突信号は端末ロ
ジック部（４）に入力されず、伝送をし続ける。まだ、
送信データ「ｌ−１を送信している端末器（２）におい
ては、アンドゲートＧ４の両入力は共にＨレベルとなる
ため、衝突信号が端末ロジック部（４）に入力されるこ
とになり、送信を停止する。FIG. 5 shows a specific circuit diagram, in which modem (3), terminal 0. ;
The check section (4) is the same as the conventional one, and the received data output from the modem (:1) and the collision signal are inverted by the inverter G2 and are ANDed by the acid gate G1. The output is used as the received data input to the terminal 0 thick unit (4). Then, the output of the AND gate G1 and the transmission data from the terminal 0 thick unit (4) are set to 1! :
X -OR gate G performs exclusive OR, and its E
The output of the X-OR gate (], and the 117 rear signal from the modem (3) are ANDed by the AND gate G,
The output of this act gate G is input to the terminal logic section (4) as a collision signal. Collision processing means 330 is configured in each of the gates 61 to 61. by this,
If data ``11'' and data ``0'' collide and it cannot be determined whether the FM demodulated carrier signal is data ``1'' or [0], the H level from tr'm (3) will collide. The signal is set to L level by inverter G2, and therefore the output of AND gate G1 is set to L level, so that the received data input to the terminal logic section (4) is always [0-
It becomes 1. At this time, if the terminal logic section (4) is transmitting data "0", the output of the EX-OR gate G becomes L level, so the collision signal is sent to the terminal logic section (4). There is no input and the transmission continues. still,
In the terminal device (2) that is transmitting the transmission data "l-1," both inputs of the AND gate G4 are at H level, so a collision signal is input to the terminal logic section (4). Stop sending.
すなわち、第６図（ａ）に示すように、両端末器（２＋
）（２２）から送信されて搬送波信号が衝突した場合、
端末器（２、）における送信データが「１」で、端末器
（２゜）の送信データが「０」であるとすると、端末器
（２Ｉ）では送信データが「１」であるために、アンド
ゲートＧ１より衝突信号が入力されて送信を停止する。That is, as shown in FIG. 6(a), both terminals (2+
) (22) and the carrier signals collide,
Suppose that the transmission data at the terminal (2,) is "1" and the transmission data at the terminal (2°) is "0", and since the transmission data at the terminal (2I) is "1", A collision signal is input from AND gate G1 and transmission is stopped.
そして、端末器（２２）は送信データがｒＯＪであるか
ら、端末ロジック部（４）に衝突信号が入力されず、信
号を伝送し続ける。そして、端末器（２，）では、十Ｐ
リア信号を受信しているだめに、信号は送信されず、端
末器（２，）の送信が終ってから、信号を開始すること
になる。第６図（ｂ）は上記と反対の場合で、端末器（
２，）の送信データが「０」で、端末器（２２）の送信
データが１１」の場合であり、上記と反対の動作をし、
端末器（２□）は信号の送信を停止し、端末器（２ハの
送信が終了してから、送信を開始することになる。次に
、両端末”ｇ：ｉ （２＋） （２２）の送信データが
共に「０」の場合には、第６図（ａ）あるいは（ｂ）の
状態捷で伝送を続ける。つ捷り、どちらかの端末器（２
，）又は（２２）の送信データが「ｌ」となった場合に
端末器（２１）又は（２２）が送信を停止することにな
る。更に、両端末器（２＋） （２２）の送信データが
共に「１」の場合にニＪ１、衝突信号が端末ロジック部
へ入力されるだめに、両端末器（２＋） （２８）の送
信は共に即時に停止し、従来と同様に一定時間ｔｄ２経
過後に、どちらかの端末器（２、）又は（２２）が送信
を開始することになる。この結果、必ず１台の端末器（
２）は確実に伝送を終了するため、衝突後の送信で再度
衝突が発生することがなくなる。Since the terminal device (22) transmits data as rOJ, no collision signal is input to the terminal logic section (4), and the terminal device (22) continues to transmit the signal. Then, in the terminal (2,), 10P
The signal is not transmitted until the rear signal is received, and the signal is started only after the terminal device (2,) has finished transmitting. Figure 6(b) shows the opposite case to the above, where the terminal (
2,) is "0" and the data transmitted by the terminal (22) is "11", and the operation is opposite to the above,
The terminal device (2□) will stop transmitting signals, and after the terminal device (2□) has finished transmitting, it will start transmitting.Next, both terminals"g:i (2+) (22) If both of the transmitted data are "0", transmission continues in the state switching shown in FIG.
, ) or (22) becomes "l", the terminal device (21) or (22) will stop transmitting. Furthermore, when the transmission data of both terminals (2+) (22) are both "1", the transmission of both terminals (2+) (28) is Both terminals stop immediately, and either terminal device (2,) or terminal device (22) starts transmitting after a certain period of time td2 has elapsed, as in the conventional case. As a result, only one terminal (
2) ensures that the transmission ends, so that no collision will occur again in transmission after a collision.
〔イＣ１明の効果〕
本発明は上述のように時分割多重伝送システムにおいて
、モデムからの受信データと衝突信号の反転信号とを論
理積して端末ロジック部への受信データ入力とし、該論
理積しだ等信データ信号と論理演算する自局の送信デー
タが予め設定した片方の２値論卯鎖信号の場合だけ端末
ロジック部への衝突信号とする衝突処理手段をモデムと
端末ロジック部との間に設けたものであるから、信号線
上で搬送波信号が衝突した場合には、モデムからの受信
データと衝突信号の反転信号とで論理積をとるととで、
端末ロジック部への受信データ入力はかくなり、寸だ、
論理積出力と自局の送信データの片方の２値論理音信号
とで論理演算して衝突信号とすることにより、該衝突信
号で当該端末器からの信号の送信は停止されるとともに
、他局の端末器において、送信データの信号が他方の２
値論理音信号の場合は、送信を続行するものであり、そ
のため、衝突が生じた場合に、必ず、共に両端末器から
送信を開始していた従来と比べ、片方の端末器は確実に
伝送を終了するだめに、衝突後の送信で再度衝突が発生
を低減させることができ、伝送時間を短縮できる効果を
奏する。[Effect of A C1 Light] As described above, in a time division multiplex transmission system, the present invention logically ANDs the received data from the modem and the inverted signal of the collision signal to input the received data to the terminal logic section. The modem and the terminal logic unit are provided with a collision processing means that outputs a collision signal to the terminal logic unit only when the transmission data of the local station that performs a logical operation on the accumulated communication data signal is one of the preset binary logic chain signals. Therefore, if carrier signals collide on the signal line, the received data from the modem and the inverted signal of the collision signal are ANDed,
The input of received data to the terminal logic section becomes difficult.
By performing a logical operation on the AND output and the binary logical sound signal of one of the transmit data of the own station to generate a collision signal, the transmission of the signal from the terminal device is stopped at the collision signal, and the transmission of the signal from the terminal is stopped, and the transmission of the signal from the other station is stopped. In a terminal device, the transmission data signal is
In the case of a value logic sound signal, transmission continues, so when a collision occurs, one terminal is able to reliably transmit data, compared to the conventional method where both terminals always start transmitting. It is possible to reduce the occurrence of another collision in transmission after a collision before the transmission ends, and the transmission time can be reduced.
第１図は時分割多重伝送システムのｖニーｉ！ル図、第
２図は同上の動作説明図、第８図は一従来の端末器のブ
ロック図、第４図は同上の動作説明図、第５図は本発明
の火力石側の端末器のプロツク回路図、第６図は同上の
動作説明図である。
（１）は信号線、（２）は端末器、（３）はｔデム、（
４）は端末ロジック部を示す。
代胛人 弁理士 石 １）長 七Figure 1 shows the time division multiplex transmission system vnee i! 2 is an explanatory diagram of the same operation as above, FIG. 8 is a block diagram of a conventional terminal device, FIG. 4 is an explanatory diagram of the same operation as above, and FIG. The block circuit diagram, FIG. 6, is an explanatory diagram of the same operation. (1) is a signal line, (2) is a terminal, (3) is a tdem, (
4) shows the terminal logic section. Proxy Patent Attorney Ishi 1) Choshichi
Claims (1)
端末器における任意の２端末器間で搬送波信号にて時分
割伝送が可能であって、各端末器は送信データや受信デ
ータの授受を行なう端末ロジック部と、該端末０シック
部と信号線との間における各データの２値論理音信号と
搬送波信号との変換を行々う℃ヂムとで構成され、複数
の端末器からの搬送波イハ号が信号線上で衝突して受信
データを判別できない場合に衝突信号を端末ロジック部
へ出力する衝突検出機能と、受信した搬送波信号を２値
論理音信号に変換して受信データとして端末ロジック部
へ出力する受信データ変換機能と、端末ロジック部から
送信データを搬送波信号に変換する送信データ変換機能
とをｔデムに有し、衝突信号により送信を即時停止して
一定時間後に送信可能とする再送信機能を端末ロジック
部に有する時分割多重伝送システムにおいて、ｔヂムか
らの受信データと衝突信号の反転信号とを論理積して端
末ロジック部への受信データ入力とじ、該論理積した受
信データ信号と論理演算する自局の送信データが予め設
定した片方の２値論理音信号の場合だけ端末ロジック部
への衝突信号とする衝突処理手段をｔデ乙と端末ｏ、；
ツク部との間に設けて成ることを特徴とする時分割多重
伝送システム。+++ Multiple terminal devices are connected to one signal line, and time-division transmission is possible between any two terminal devices in each terminal device using a carrier wave signal, and each terminal device transmits and receives data. It is composed of a terminal logic section that performs sending and receiving, and a ℃jim that converts each data into a binary logic sound signal and a carrier wave signal between the terminal 0 thick section and the signal line, and is connected to a plurality of terminal devices. A collision detection function that outputs a collision signal to the terminal logic section when the carrier waves from IHA collide on the signal line and the received data cannot be determined, and a collision detection function that outputs a collision signal to the terminal logic section and converts the received carrier wave signal into a binary logic sound signal and uses it as received data. The t-dem has a reception data conversion function that outputs to the terminal logic section and a transmission data conversion function that converts the transmission data from the terminal logic section into a carrier wave signal, and can immediately stop transmission in response to a collision signal and transmit after a certain period of time. In a time division multiplex transmission system having a retransmission function in the terminal logic section, the received data from the tDM and the inverted signal of the collision signal are ANDed and the received data is input to the terminal logic section. A collision processing means is provided for generating a collision signal to the terminal logic section only when the transmission data of the local station that performs a logical operation on the received data signal is one of the preset binary logical tone signals;
1. A time division multiplex transmission system characterized by being provided between a terminal and a terminal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16984783A JPS6062255A (en) | 1983-09-14 | 1983-09-14 | Time-division multiplex transmission system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16984783A JPS6062255A (en) | 1983-09-14 | 1983-09-14 | Time-division multiplex transmission system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS6062255A true JPS6062255A (en) | 1985-04-10 |
Family
ID=15894033
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP16984783A Pending JPS6062255A (en) | 1983-09-14 | 1983-09-14 | Time-division multiplex transmission system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6062255A (en) |
-
1983
- 1983-09-14 JP JP16984783A patent/JPS6062255A/en active Pending
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