JPH05260021A - Communication control system - Google Patents
Communication control systemInfo
- Publication number
- JPH05260021A JPH05260021A JP4054054A JP5405492A JPH05260021A JP H05260021 A JPH05260021 A JP H05260021A JP 4054054 A JP4054054 A JP 4054054A JP 5405492 A JP5405492 A JP 5405492A JP H05260021 A JPH05260021 A JP H05260021A
- Authority
- JP
- Japan
- Prior art keywords
- bit sequence
- error
- control system
- known bit
- already known
- 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.)
- Withdrawn
Links
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- Detection And Correction Of Errors (AREA)
- Detection And Prevention Of Errors In Transmission (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、通信制御方式、特に通
信路の特性が変化する環境において有効となる通信制御
方式に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication control system, and more particularly to a communication control system effective in an environment where the characteristics of a communication path change.
【０００２】[0002]
【従来の技術】今、もし理想的に良好な特性を持つ通信
路を用いて通信が行なえるとすれば、送信機から送出さ
れた情報信号は、受信機で誤ることなく再生される筈で
ある。しかし実際には、上述のような理想的な状況は皆
無であり、ある程度の誤りは生じる。2. Description of the Related Art Now, if it is possible to perform communication using a channel having ideally good characteristics, the information signal transmitted from the transmitter should be reproduced without error in the receiver. is there. However, in reality, there is no ideal situation as described above, and some errors occur.
【０００３】また、特に無線通信において顕著に現れる
が、通信路の特性が周囲の環境の変化等により時々刻々
変化することがあり、誤りの発生頻度も変化する。そこ
で、ディジタル通信においては、情報信号に冗長ビット
を付加することにより、通信路において生じた情報信号
内のビットの誤りを検出したり、訂正したりする。[0003] In addition, particularly in wireless communication, the characteristics of the communication path may change from moment to moment due to changes in the surrounding environment, and the frequency of occurrence of errors also changes. Therefore, in digital communication, a redundant bit is added to the information signal to detect or correct an error in the bit in the information signal generated in the communication path.
【０００４】誤り検出符号として代表的なものには、奇
数値の誤りが検出可能なパリティ検査符号、また誤り訂
正符号としては、巡回符号の一つであるＢＣＨ符号があ
り、どちらの符号も一般によく利用される。また、複数
の誤り制御符号を組み合わせて利用することも良く行な
われ、例えば情報信号をパリティ検査符号化し、更にＢ
ＣＨ符号化するという方式もある。A typical error detection code is a parity check code capable of detecting an odd number of errors, and an error correction code is a BCH code which is one of cyclic codes. Both codes are generally used. Often used. It is also common to use a plurality of error control codes in combination. For example, an information signal is subjected to parity check coding, and further B
There is also a method of CH coding.
【０００５】[0005]
【発明が解決しようとする課題】ところで通信システム
において利用する誤り制御方式を決定する際には、通信
路の特性が悪化したときのことを考慮し、誤りの検出や
誤り訂正の能力の高い符号を選択する方が情報の信頼性
が高まることになる。しかし、一般に能力の高い符号を
復号するときには計算量が増えたり、処理が複雑になっ
たりする傾向がある。By the way, when determining an error control method to be used in a communication system, a code having a high error detection and error correction capability is considered in consideration of the deterioration of the characteristics of the communication path. Choosing will increase the reliability of the information. However, in general, when decoding a code having high capability, the amount of calculation tends to increase and the processing tends to become complicated.
【０００６】本発明は上述の問題点に鑑みて為されたも
ので、その目的とするところは通信路の特性の変化に応
じて情報信号の誤り制御方式を変化させることができ、
効率的な受信処理が行なえる通信制御方式を提供するに
ある。The present invention has been made in view of the above problems, and an object thereof is to change an error control system of an information signal according to a change in characteristics of a communication path.
It is to provide a communication control method capable of performing efficient reception processing.
【０００７】[0007]
【課題を解決するための手段】上記目的を達成するため
に、本発明は、単一或いは複数の誤り制御符号を含む情
報信号に、既知のビット系列を付加した信号を用いて通
信を行なう通信システムにおいて、受信時の上記既知ビ
ット系列内の誤りビット数を計数する手段を有した受信
機が、上記誤りビット数に応じて、情報信号の誤り制御
方式を変化させることを特徴とするものである。In order to achieve the above object, the present invention is a communication for performing communication by using a signal obtained by adding a known bit sequence to an information signal including a single or a plurality of error control codes. In the system, the receiver having means for counting the number of error bits in the known bit sequence at the time of reception changes the error control method of the information signal according to the number of error bits. is there.
【０００８】尚既知ビット系列が、フレーム同期信号で
あっても、既知ビット系列が、情報信号の中央部に挿入
されたビット系列であっても良い。The known bit sequence may be a frame synchronization signal or the known bit sequence may be a bit sequence inserted in the center of the information signal.
【０００９】[0009]
【作用】而して本発明によれば、受信した既知ビット系
列内の誤りビット数から通信路の特性を検知することが
でき、この検知した特性に応じて情報信号の誤り制御方
式を変化させることが可能となるので、受信処理を効率
的に行なうことができる。Thus, according to the present invention, the characteristic of the communication path can be detected from the number of error bits in the received known bit sequence, and the error control method of the information signal is changed according to the detected characteristic. Therefore, the receiving process can be performed efficiently.
【００１０】[0010]
【実施例】以下本発明を実施例により説明する。図２は
本発明方式を採用する通信システムに用いる信号の概念
的構成例を示しており、この信号は送受信機間で予め決
められた既知ビット系列Ａ及びＢＣＨ符号化された情報
信号Ｂとからなる。EXAMPLES The present invention will be described below with reference to examples. FIG. 2 shows an example of a conceptual configuration of a signal used in a communication system adopting the method of the present invention. This signal is composed of a known bit sequence A and a BCH-coded information signal B which are predetermined between the transmitter and the receiver. Become.
【００１１】受信機は、受信信号の誤り制御を行なうよ
り前に、前記既知のビット系列Ａにおける誤りビット数
を計数する手段を備えている。この処理を図１を用いて
説明する。まず、受信信号の受信既知ビット系列Ａを受
信既知ビット系列格納領域に入れ、次いで予め既知ビッ
ト系列記憶領域内に記憶している記憶既知ビット系列
Ａ’と受信既知ビット系列格納領域に入れた上記受信既
知ビット系列Ａとを排他的論理和演算を行い、この演
算結果を演算結果格納領域に入れる。The receiver comprises means for counting the number of error bits in the known bit sequence A before performing error control of the received signal. This process will be described with reference to FIG. First, the received known bit sequence A of the received signal is placed in the received known bit sequence storage area, and then the stored known bit sequence A ′ and the received known bit sequence storage area stored in advance in the known bit sequence storage area are inserted. An exclusive OR operation is performed on the received known bit sequence A, and the operation result is stored in the operation result storage area.
【００１２】ここでもし受信既知ビット系列Ａに誤りが
全く無い場合には、前記演算結果格納領域内の演算結果
のビットは全て０となるが、誤りがある場合にはその
誤りビットに対応する演算結果格納領域内の演算結果
のビットが１となる。よって、図２の既知ビット系列Ａ
における誤りビットを知るためには、図１の演算結果格
納領域に入れた演算結果における１のビット数を計数
すればよい。Here, if there is no error in the received known bit sequence A, all bits of the operation result in the operation result storage area are 0, but if there is an error, it corresponds to the error bit. The bit of the operation result in the operation result storage area becomes 1. Therefore, the known bit sequence A in FIG.
In order to know the error bit in, the number of bits of 1 in the operation result stored in the operation result storage area of FIG. 1 may be counted.
【００１３】ここで通信路の特性は、この計数結果の値
が小さいときには良く、逆に大きいときには悪いと判断
される 。一般に、ディジタル通信においては図３
（ａ）に示すようにビット同期信号ＢＳ、フレーム同期
信号ＦＳ、情報信号Ｂからなる信号を用いるが、通信路
の特性を検知する既知ビット系列Ａとして、フレーム同
期信号ＦＳを用いれば、上述の既知ビット系列Ａにおけ
る誤りビットの計数はフレーム同期判定と同時に行なう
ことができる。Here, it is judged that the characteristics of the communication path are good when the value of the counting result is small, and conversely when it is large. Generally, in digital communication, FIG.
As shown in (a), a signal including a bit synchronization signal BS, a frame synchronization signal FS, and an information signal B is used, but if the frame synchronization signal FS is used as the known bit sequence A for detecting the characteristics of the communication path, The error bit count in the known bit sequence A can be performed simultaneously with the frame synchronization determination.
【００１４】また図３（ｂ）に示すように情報信号Ｂ1
とＢ2 との間に既知ビット系列Ａを挿入すれば、通信路
の特性変化が急速な時には、信号の前部や後部に既知ビ
ット系列Ａを置く場合と比較して、平均化された特性を
求めることができる。ところで、上記実施例おいて情報
信号Ｂに施されているＢＣＨ符号は、誤り訂正符号とし
て良く知られているが、これを誤り検出符号として用い
ることも可能であり、この時には訂正可能ビット数より
も大きな値の検出可能ビット数を持ち、処理は誤り訂正
の時よりも簡単になる。Further, as shown in FIG. 3B, the information signal B 1
If a known bit sequence A is inserted between B 2 and B 2 , when the characteristic change of the communication path is rapid, the averaged characteristic is compared with the case where the known bit sequence A is placed at the front or the rear of the signal. Can be asked. By the way, the BCH code applied to the information signal B in the above embodiment is well known as an error correction code, but it is also possible to use this as an error detection code. Also has a large number of detectable bits, and the processing becomes easier than in the case of error correction.
【００１５】よって、通信路の特性に応じて、誤り制御
方式を変化させることにより、効率的な受信処理が可能
となる。表１はこの誤り制御方式を変化させる場合の例
を示している。Therefore, by changing the error control method according to the characteristics of the communication path, efficient reception processing becomes possible. Table 1 shows an example of changing the error control method.
【００１６】[0016]
【表１】 [Table 1]
【００１７】表１に示した場合は、まず既知ビット系列
Ａ内の誤りビット数が０で通信路の特性が非常に良好で
あると思われる際に、受信情報信号Ｂに誤りが殆ど無い
と、考えられるので、誤り検出のみの誤り制御方式を採
用する。次に、既知ビット系列Ａ内の誤りビット数が１
となるような通信路の特性を持つときには、誤り訂正の
誤り制御方式を採用する。但し、このときには、受信情
報信号Ｂ内にＢＣＨ符号の誤り訂正能力を越えないよう
な誤りしか生じないことが条件となる。In the case shown in Table 1, first, when the number of error bits in the known bit sequence A is 0 and the characteristics of the communication path are considered to be very good, the received information signal B has almost no error. Therefore, the error control method of only error detection is adopted. Next, the number of error bits in the known bit sequence A is 1
If there is such a characteristic of the communication path that becomes, the error control method of error correction is adopted. However, at this time, the condition is that only errors that do not exceed the error correction capability of the BCH code occur in the received information signal B.
【００１８】既知ビット系列Ａ内の誤りビット数が２と
なり、受信情報信号Ｂ内にＢＣＨ符号の誤り訂正能力を
越えるような誤りが生じると考えられる際には、誤訂正
を防ぐために、再び誤り検出を行なう。更に通信路の特
性が非常に悪く、既知ビット系列Ａ内の誤りビット数が
３以上となるようなときには、受信情報信号Ｂ内に誤り
が多く、信頼性がないと考えられるので、復号を行なわ
ず、受信情報信号Ｂを棄却する。When the number of error bits in the known bit sequence A becomes 2, and it is considered that an error that exceeds the error correction capability of the BCH code occurs in the received information signal B, the error is corrected again to prevent erroneous correction. Perform detection. Further, when the characteristics of the communication channel are extremely poor and the number of error bits in the known bit sequence A is 3 or more, it is considered that there are many errors in the received information signal B and it is considered unreliable, so decoding is performed. Instead, the received information signal B is rejected.
【００１９】尚表１の例は誤り制御方式を変化させる場
合の一方法を示しているに過ぎず、特に表１の場合に限
定されるものでなく、その他様々な方法があることは言
うまでもない。また使用する誤り制御方式も表１の例に
限定されるものでないことは、言うまでもない。The example of Table 1 shows only one method for changing the error control method, and is not limited to the case of Table 1, and it goes without saying that there are various other methods. .. Needless to say, the error control method used is not limited to the example shown in Table 1.
【００２０】[0020]
【発明の効果】本発明は、単一或いは複数の誤り制御符
号を含む情報信号に、既知のビット系列を付加した信号
を用いて通信を行なう通信システムにおいて、受信時の
上記既知ビット系列内の誤りビット数を計数する手段を
有した受信機が、上記誤りビット数に応じて、情報信号
の誤り制御方式を変化させるから、受信した既知ビット
系列内の誤りビット数から通信路の特性を検知すること
ができ、この検知した特性に応じて情報信号の誤り制御
方式を変化させることが可能となるので、受信処理を効
率的に行なうことができるという効果がある。According to the present invention, in a communication system for performing communication using a signal in which a known bit sequence is added to an information signal containing a single or a plurality of error control codes, the known bit sequence in the reception Since the receiver having means for counting the number of error bits changes the error control method of the information signal according to the number of error bits, the characteristic of the communication channel is detected from the number of error bits in the received known bit sequence. Since it is possible to change the error control method of the information signal according to the detected characteristic, there is an effect that the receiving process can be efficiently performed.
【図１】本発明の一実施例の概念的な信号処理の流れを
説明する説明図である。FIG. 1 is an explanatory diagram illustrating a conceptual flow of signal processing according to an embodiment of the present invention.
【図２】同上を使用する通信システムに用いる信号の構
成説明図である。FIG. 2 is an explanatory diagram of a signal configuration used in a communication system using the same as above.
【図３】（ａ）は同上を使用する通信システムに用いる
信号の他の例の構成説明図である。（ｂ）は同上を使用
する通信システムに用いる信号の別の例の構成説明図で
ある。FIG. 3 (a) is a configuration explanatory diagram of another example of a signal used in a communication system using the same as above. (B) is an explanatory view of the configuration of another example of the signal used in the communication system using the same as above.
Ａ 受信既知ビット系列 Ａ’ 記憶既知ビット系列 排他的論理和演算 演算結果 A Received known bit sequence A'Memory known bit sequence Exclusive OR operation Operation result
─────────────────────────────────────────────────────
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【手続補正書】[Procedure amendment]
【提出日】平成４年８月３日[Submission date] August 3, 1992
【手続補正１】[Procedure Amendment 1]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】０００４[Correction target item name] 0004
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【０００４】誤り検出符号として代表的なものには、奇
数個の誤りが検出可能なパリティ検査符号、また誤り訂
正符号としては、巡回符号の一つであるＢＣＨ符号があ
り、どちらの符号も一般によく利用される。また、複数
の誤り制御符号を組み合わせて利用することも良く行な
われ、例えば情報信号をパリティ検査符号化し、更にＢ
ＣＨ符号化するという方式もある。A typical error detection code is a parity check code capable of detecting an odd number of errors, and an error correction code is a BCH code which is one of cyclic codes. Both codes are generally used. Often used. It is also common to use a plurality of error control codes in combination. For example, an information signal is parity-check coded, and then B
There is also a method of CH coding.
【手続補正２】[Procedure Amendment 2]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】０００５[Correction target item name] 0005
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【０００５】[0005]
【発明が解決しようとする課題】ところで通信システム
において利用する誤り制御方式を決定する際には、通信
路の特性が悪化したときのことを考慮し、誤り検出や誤
り訂正の能力の高い符号を選択する方が情報の信頼性が
高まることになる。しかし、一般に能力の高い符号を復
号するときには計算量が増えたり、処理が複雑になった
りする傾向がある。In determining the error control scheme utilized in the way a communication system [0005] In consideration that when the characteristics of the communication channel is deteriorated, high capacity erroneous Riken unloading and error correction Choosing a code will increase the reliability of the information. However, in general, when decoding a code having high capability, the amount of calculation tends to increase and the processing tends to become complicated.
【手続補正３】[Procedure 3]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００１２[Correction target item name] 0012
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【００１２】ここでもし受信既知ビット系列Ａに誤りが
全く無い場合には、前記演算結果格納領域内の演算結果
のビットは全て０となるが、誤りがある場合にはその
誤りビットに対応する演算結果格納領域内の演算結果
のビットが１となる。よって、図２の既知ビット系列Ａ
における誤りビット数を知るためには、図１の演算結果
格納領域に入れた演算結果における１のビット数を計
数すればよい。Here, if there is no error in the received known bit sequence A, all bits of the operation result in the operation result storage area are 0, but if there is an error, it corresponds to the error bit. The bit of the operation result in the operation result storage area becomes 1. Therefore, the known bit sequence A in FIG.
In order to know the number of error bits in, the number of bits of 1 in the operation result put in the operation result storage area of FIG. 1 may be counted.
【手続補正４】[Procedure amendment 4]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００１４[Correction target item name] 0014
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【００１４】また図３（ｂ）に示すように情報信号Ｂ1
とＢ2 との間に既知ビット系列Ａを挿入すれば、通信路
の特性変化が急速な時には、信号の前部や後部に既知ビ
ット系列Ａを置く場合と比較して、平均化された特性を
求めることができる。ところで、上記実施例において情
報信号Ｂに施されているＢＣＨ符号は、誤り訂正符号と
して良く知られているが、これを誤り検出符号として用
いることも可能であり、この時には訂正可能ビット数よ
りも大きな値の検出可能ビット数を持ち、処理は誤り訂
正の時よりも簡単になる。Further, as shown in FIG. 3B, the information signal B 1
If the known bit sequence A is inserted between B and B 2 , when the characteristic change of the communication path is rapid, the averaged characteristic is compared with the case where the known bit sequence A is placed at the front or the rear of the signal. Can be asked. Meanwhile, BCH code has been applied to Oite information signal B to the above embodiment, although well known as an error correction code, which is also possible to use as the error detection code, correctable number of bits at this time It has a larger number of detectable bits, and the process is simpler than in error correction.
【手続補正５】[Procedure Amendment 5]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００１７[Correction target item name] 0017
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【００１７】表１に示すように、まず既知ビット系列Ａ
内の誤りビット数が０で通信路の特性が非常に良好であ
ると思われる際には、受信情報信号Ｂに誤りが殆ど無い
と、考えられるので、誤り検出のみの誤り制御方式を採
用する。次に、既知ビット系列Ａ内の誤りビット数が１
となるような通信路の特性を持つときには、誤り訂正の
誤り制御方式を採用する。但し、このときには、受信情
報信号Ｂ内にＢＣＨ符号の誤り訂正能力を越えないよう
な誤りしか生じないことが条件となる。As shown in Table 1, first, a known bit sequence A
When the characteristics of the communication path error bit number 0 of the inner appears to be very good, when there is little error in the received information signal B, it is considered to employ the error control scheme of only the error detection .. Next, the number of error bits in the known bit sequence A is 1
If there is such a characteristic of the communication path that becomes, the error control method of error correction is adopted. However, at this time, the condition is that only errors that do not exceed the error correction capability of the BCH code occur in the received information signal B.
Claims (3)
信号に、既知のビット系列を付加した信号を用いて通信
を行なう通信システムにおいて、受信時の上記既知ビッ
ト系列内の誤りビット数を計数する手段を有した受信機
が、上記誤りビット数に応じて、情報信号の誤り制御方
式を変化させることを特徴とする通信制御方式。1. In a communication system for performing communication using a signal obtained by adding a known bit sequence to an information signal containing a single or a plurality of error control codes, the number of error bits in the known bit sequence at the time of reception is calculated. A communication control system, wherein a receiver having a counting unit changes an error control system of an information signal according to the number of error bits.
ることを特徴とする請求項１記載の通信制御方式。2. The communication control system according to claim 1, wherein the known bit sequence is a frame synchronization signal.
入されたビット系列であることを特徴とする請求項１記
載の通信制御方式。3. The communication control system according to claim 1, wherein the known bit sequence is a bit sequence inserted in the central portion of the information signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4054054A JPH05260021A (en) | 1992-03-13 | 1992-03-13 | Communication control system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4054054A JPH05260021A (en) | 1992-03-13 | 1992-03-13 | Communication control system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH05260021A true JPH05260021A (en) | 1993-10-08 |
Family
ID=12959906
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4054054A Withdrawn JPH05260021A (en) | 1992-03-13 | 1992-03-13 | Communication control system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH05260021A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7804891B2 (en) | 2004-03-31 | 2010-09-28 | Kabushiki Kaisha Kenwood | Device and method for judging communication quality and program used for the judgment |
| US8327239B2 (en) | 2007-02-19 | 2012-12-04 | Sony Corporation | Communication device, communication method, and computer program |
-
1992
- 1992-03-13 JP JP4054054A patent/JPH05260021A/en not_active Withdrawn
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7804891B2 (en) | 2004-03-31 | 2010-09-28 | Kabushiki Kaisha Kenwood | Device and method for judging communication quality and program used for the judgment |
| US8327239B2 (en) | 2007-02-19 | 2012-12-04 | Sony Corporation | Communication device, communication method, and computer program |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A300 | Withdrawal of application because of no request for examination |
Free format text: JAPANESE INTERMEDIATE CODE: A300 Effective date: 19990518 |