JPH05183531A - Receiver - Google Patents
ReceiverInfo
- Publication number
- JPH05183531A JPH05183531A JP34658491A JP34658491A JPH05183531A JP H05183531 A JPH05183531 A JP H05183531A JP 34658491 A JP34658491 A JP 34658491A JP 34658491 A JP34658491 A JP 34658491A JP H05183531 A JPH05183531 A JP H05183531A
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- JP
- Japan
- Prior art keywords
- signal
- error
- error detection
- received
- discriminated
- 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.)
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Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は２種類以上の信号を同一
の通信路を介して伝送する多重伝送システムに係り、さ
らに詳しくは、その多重伝送信号の受信装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multiplex transmission system for transmitting two or more kinds of signals through the same communication path, and more particularly to a receiver for the multiplex transmission signals.
【０００２】[0002]
【従来の技術】２種類以上の信号を同一の通信路を介し
て伝送する多重伝送は多くの通信システムに用いられて
いる。2. Description of the Related Art Multiplex transmission for transmitting two or more kinds of signals through the same communication path is used in many communication systems.
【０００３】この多重伝送は通信回線を効率良く利用
し、かつ、通信装置を簡易に構成するための技術であっ
て、加入者が送信する情報信号に通信網提供者が回線制
御のための情報信号を多重して伝送することが多い。例
えばＰＣＭ基幹電話回線の１次群伝送信号は１．５３６
Ｍｂ／ｓのＰＣＭ音声信号にフレーム信号を含む制御信
号を時分割的に挿入して１．５４４Ｍｂ／ｓの信号とし
て伝送している。受信側ではフレーム同期を確立した
後、フレーム内の予め定まった区間で送信されている制
御信号とＰＣＭ音声信号とを受信したフレーム内の受信
位置により区別している。This multiplex transmission is a technique for efficiently using a communication line and simply configuring a communication device, and an information signal transmitted by a subscriber is used by a communication network provider to control the line. In many cases, signals are multiplexed and transmitted. For example, the primary group transmission signal of the PCM backbone telephone line is 1.536
A control signal including a frame signal is time-divisionally inserted into an Mb / s PCM audio signal and transmitted as a 1.544 Mb / s signal. After the frame synchronization is established on the receiving side, the control signal and the PCM audio signal transmitted in a predetermined section within the frame are distinguished by the receiving position within the frame where the signal is received.
【０００４】また、パケット状の信号伝送方式として、
ＨＤＬＣ手順を用いた信号伝送では、プリアンブル信号
の後に付加されたコマンド識別信号により情報信号か制
御信号かを区別している。As a packet-like signal transmission system,
In signal transmission using the HDLC procedure, a command identification signal added after the preamble signal distinguishes between an information signal and a control signal.
【０００５】しかしながら、これらの方法では定常的に
制御信号を挿入したりパケット毎にコマンド識別信号を
付与するため、通信回線の伝送速度は情報信号の伝送速
度より高く設定する必要がある。これは、周波数の有効
利用が強く求められる無線回線では特に大きな問題とな
る。However, in these methods, since the control signal is constantly inserted and the command identification signal is added to each packet, the transmission speed of the communication line must be set higher than the transmission speed of the information signal. This is a particularly serious problem in a wireless line where effective use of frequencies is strongly required.
【０００６】ところで、無線回線のビット誤り率は一般
に有線回線に比べて高く、無線回線を介して情報を高信
頼度で伝送するには、誤り訂正や誤り検出といった誤り
制御技術の利用が不可欠である。例えば、音声を８Ｋｂ
／ｓ程度のデータ信号に圧縮して伝送するときには、歪
感度の高い音声信号のパラメータに誤り検出符号を付加
し、誤りが検出されたときには、当該フレームを前のフ
レームのパラメータに置き換えたり、音声信号をマスク
して、異音が生じないようにして再生音声品質を向上さ
せる方法が知られている。また、各種制御信号を送信す
る際には、誤り検出符号を付加して送信し、誤った場合
には、制御信号の再送を要求する方法が広く用いられて
いる。By the way, the bit error rate of a wireless line is generally higher than that of a wired line, and in order to transmit information via the wireless line with high reliability, it is essential to use error control technology such as error correction and error detection. is there. For example, 8Kb voice
When the data is compressed into a data signal of about 1 / s and transmitted, an error detection code is added to the parameter of the voice signal having high distortion sensitivity. When an error is detected, the frame is replaced with the parameter of the previous frame, A method is known in which a signal is masked so as to prevent abnormal noise from being generated, thereby improving reproduced voice quality. In addition, when various control signals are transmitted, a method of adding an error detection code and transmitting them, and if they are incorrect, a method of requesting retransmission of the control signal is widely used.
【０００７】このように無線通信システムにおいて、前
述したような方法で２種類以上の信号を同一チャネルで
伝送すると、誤り制御のために付加される冗長信号に信
号識別のために付加される信号を加えてるため、さらに
周波数の利用効率が低下することになる。As described above, in the wireless communication system, when two or more kinds of signals are transmitted on the same channel by the above-described method, the redundant signal added for error control is added to the redundant signal added for signal identification. Because of the addition, the frequency utilization efficiency is further reduced.
【０００８】また、誤り制御信号を付加しない信号識別
信号は伝送中生じた誤りを受信側で識別できなくなるた
め受信信号の信頼度が低下するという問題があった。Further, the signal identification signal to which the error control signal is not added has a problem that the reliability of the received signal is lowered because an error occurring during transmission cannot be identified on the receiving side.
【０００９】[0009]
【発明が解決しようとする課題】上述したように従来の
多重伝送によると誤り制御のために付加される冗長信号
に信号識別のために付加される信号を加えてるため、周
波数の利用効率が低下するという問題があった。As described above, according to the conventional multiplex transmission, since the signal added for signal identification is added to the redundant signal added for error control, the frequency utilization efficiency is lowered. There was a problem to do.
【００１０】本発明はこの点に鑑みなされたもので周波
数の利用効率を高く保ったまま２種類以上の信号を伝送
できる多重信号伝送を実現することにある。The present invention has been made in view of this point, and it is an object of the present invention to realize multiplex signal transmission capable of transmitting two or more kinds of signals while maintaining high frequency utilization efficiency.
【００１１】[0011]
【課題を解決するための手段】上述した目的を達成する
ため、第１の発明は、第１の情報信号および第２の情報
信号に、それぞれ、第１の誤り検出符号と前記第１の誤
り検出符号よりも信頼度の高い第２の誤り検出符号を付
加して送信された信号を受信する受信装置であって、前
記第２の誤り検出符号によって前記送信された信号の誤
り検出を行う誤り検出手段と、前記誤り検出手段によっ
て誤り検出を実行した結果、誤りが無かった場合には前
記第２の情報信号を受信していると判定し、誤りがあっ
た場合には前記第１の情報信号を受信していると判定す
る受信信号判定手段とを具備した受信装置である。そし
て前記第２の誤り検出確率は前記第１の誤り検出符号よ
りも検出見逃し確率は低くい信頼度が高い。In order to achieve the above-mentioned object, the first invention provides a first error detection code and a first error detection code in a first information signal and a second information signal, respectively. A receiving device for receiving a signal transmitted by adding a second error detecting code having a higher reliability than the detecting code, wherein the error detecting the error of the transmitted signal by the second error detecting code. As a result of performing error detection by the detection means and the error detection means, it is determined that the second information signal is received when there is no error, and when there is an error, the first information is received. The reception device includes a reception signal determination unit that determines that a signal is being received. The second error detection probability has a lower detection miss probability and higher reliability than the first error detection code.
【００１２】第２の発明は、第１の発明において、前記
第２の誤り検出符号を生成するための生成多項式の次数
は前記第１の誤り検出符号を生成するための生成多項式
の次数より高いことを特徴とする受信装置であり、In a second aspect based on the first aspect, the degree of the generator polynomial for generating the second error detection code is higher than the degree of the generator polynomial for generating the first error detection code. It is a receiving device characterized by that,
【００１３】[0013]
【作用】第１の情報信号と第２の情報信号の各々に対し
て、異なる誤り検出符号を付加することにより、誤り検
出符号の判別だけでどちらの情報信号を受信したかを判
別できる。さらに、２つの誤り検出符号のうち、高い信
頼度で誤りを検出できる誤り検出符号だけを用いること
により、正しく判別できる確率を高めることができる。By adding different error detection codes to each of the first information signal and the second information signal, it is possible to determine which information signal has been received only by determining the error detection code. Furthermore, of the two error detection codes, by using only the error detection code that can detect an error with high reliability, the probability of correct discrimination can be increased.
【００１４】[0014]
【実施例】以下、本発明の実施例を図面を用いて説明す
る。Embodiments of the present invention will be described below with reference to the drawings.
【００１５】図１は多重伝送信号の送信装置の構成を示
すブロック図である。FIG. 1 is a block diagram showing the structure of a transmitter for multiplex transmission signals.
【００１６】同図に示すように、この多重伝送信号の送
信装置はＣＲＣ(cyclic redundancycheck) ビットを付
加する誤り検出符号化器１０、２０、選択回路３０、パ
ケット信号生成回路４０、変調器５０とを具備してい
る。As shown in FIG. 1, the transmitter of this multiplex transmission signal includes error detection encoders 10 and 20, which add CRC (cyclic redundancy check) bits, a selection circuit 30, a packet signal generation circuit 40, and a modulator 50. It is equipped with.
【００１７】つぎに上述した送信装置の動作について説
明する。Next, the operation of the above-mentioned transmitter will be described.
【００１８】まず端子２００から第１の信号であるディ
ジタル化された音声信号が入力される。この音声信号は
音声符号化装置（図示せず）によって例えば２０ｍｓｅ
ｃ毎に１６０ビットからなる１組のパラメータに変換さ
れた信号である。誤り検出符号化器１０は端子２００か
ら受入する信号の内で再生音声の品質に大きく寄与する
パラメータを対象として第１のＣＲＣビットを付加し、
第１の符号化信号Ｓ１０１を生成する。この第１のＣＲ
Ｃビットは第１の生成多項式 Ｇ1 （ｘ）＝ｘ7 ＋ｘ5 ＋ｘ4 ＋ｘ3 ＋ｘ2 ＋ｘ＋１ を用いて生成する。即ち、受信信号を生成多項式Ｇ
1 （ｘ）で除算し、剰余をチェックビットとする。First, the digitized audio signal which is the first signal is input from the terminal 200. This speech signal is, for example, 20 mse by a speech coding device (not shown).
It is a signal converted into a set of parameters consisting of 160 bits for each c. The error detection encoder 10 adds the first CRC bit to the parameter that greatly contributes to the quality of the reproduced voice in the signal received from the terminal 200,
The first encoded signal S101 is generated. This first CR
The C bit is generated using the first generator polynomial G 1 (x) = x 7 + x 5 + x 4 + x 3 + x 2 + x + 1. That is, the received signal is generated by the polynomial G
Divide by 1 (x) and use the remainder as a check bit.
【００１９】端子２０１には第２の信号である回線制御
信号が入力される。回線制御信号は必要が生じたときだ
け間欠的に送信されるもので、例えば、自動車電話で
は、ハンドオフ時の切り替え信号やオンフック信号を始
めとした基地局からの各種制御信号が送られる。誤り検
出符号化器２０は端子２０１から受入した信号に第２の
ＣＲＣビットを付加し、第２の符号化信号Ｓ１０２を生
成する。第２のＣＲＣビットは、第２の生成多項式は Ｇ2 （ｘ）＝ｘ16＋ｘ12＋ｘ5 ＋１ により生成する。A line control signal, which is a second signal, is input to the terminal 201. The line control signal is transmitted intermittently only when the need arises. For example, in a car telephone, various control signals from the base station such as a handoff switching signal and an on-hook signal are transmitted. The error detection encoder 20 adds the second CRC bit to the signal received from the terminal 201 to generate the second encoded signal S102. The second CRC bit is generated by the second generator polynomial according to G 2 (x) = x 16 + x 12 + x 5 +1.
【００２０】選択回路３０は誤り検出符号化器１０、２
０から受入する信号を端子２０２から指示される制御信
号に従って選択し、選択した符号化信号Ｓ１０３をパケ
ット信号生成回路４０に出力する。端子２０２に入力さ
れる信号は回線制御信号を送信するときだけ、誤り検出
符号化器２０から受入する信号を選択するよう指示する
ものである。パケット信号生成回路４０では、入力され
た信号にクロック同期用のプリアンブル信号とパケット
識別のための同期信号とを付加する。この信号は、変調
器５０を介して端子２０３から伝送路に出力される。The selection circuit 30 includes error detection encoders 10, 2
The signal received from 0 is selected according to the control signal instructed from the terminal 202, and the selected encoded signal S103 is output to the packet signal generation circuit 40. The signal input to the terminal 202 instructs to select the signal to be received from the error detection encoder 20 only when transmitting the line control signal. The packet signal generation circuit 40 adds a preamble signal for clock synchronization and a synchronization signal for packet identification to the input signal. This signal is output from the terminal 203 to the transmission line via the modulator 50.
【００２１】図２は本発明の一実施例である多重伝送信
号の受信装置の構成を示すブロック図である。FIG. 2 is a block diagram showing a configuration of a multiplex transmission signal receiving apparatus according to an embodiment of the present invention.
【００２２】同図に示すようにこの多重伝送信号の受信
装置は、信号を復調する復調器６０と、復調した信号を
パケットに分解するパケット分解回路７０と、受信信号
からディジタル化された音声信号であるのか制御信号で
あるのかを判別する受信信号判別回路８０と、バッファ
９０とを具備している。As shown in the figure, the receiver for this multiplex transmission signal comprises a demodulator 60 for demodulating the signal, a packet decomposing circuit 70 for decomposing the demodulated signal into packets, and a voice signal digitized from the received signal. It is provided with a reception signal discriminating circuit 80 for discriminating whether the signal is a control signal or a control signal, and a buffer 90.
【００２３】そして端子２０４に伝送路から受信された
信号は復調器６０で基底帯域の信号に変換される。パケ
ット分解回路７０はこの基底帯域の信号から同期信号を
検出して符号化信号Ｓ１０４を取り出す。伝送路で誤り
が生じなければ、この符号化信号Ｓ１０４は、符号化信
号Ｓ１０３と等しい。この符号化信号Ｓ１０４はバッフ
ァ９０に一旦記憶される。受信信号判別回路８０は第２
のＣＲＣ信号を用いて、この符号化信号Ｓ１０４が、デ
ィジタル化された音声信号であるのか制御信号であるの
かを判別する。信号の判別は次の手順で行う。まず、受
入した符号化信号Ｓ１０４を生成多項式 Ｇ2 （ｘ）＝ｘ16＋ｘ12＋ｘ5 ＋１ により除算し、その剰余を求める。剰余が零であれば制
御信号と判別し、一方、剰余が零でなければディジタル
音声信号と判別する。この判別結果は端子２０５から出
力される。バッファ９０に記憶されていた符号化信号
は、この判別結果と同期して、端子２０６に出力され
る。The signal received from the transmission line at the terminal 204 is converted into a baseband signal by the demodulator 60. The packet disassembling circuit 70 detects the sync signal from the baseband signal and extracts the encoded signal S104. If no error occurs on the transmission path, the coded signal S104 is equal to the coded signal S103. This encoded signal S104 is temporarily stored in the buffer 90. The received signal discrimination circuit 80 is the second
The CRC signal is used to determine whether the encoded signal S104 is a digitized voice signal or a control signal. The discrimination of the signal is performed by the following procedure. First, the received encoded signal S104 is divided by the generator polynomial G 2 (x) = x 16 + x 12 + x 5 +1 to obtain the remainder. If the remainder is zero, it is determined to be a control signal, while if the remainder is not zero, it is determined to be a digital audio signal. The determination result is output from the terminal 205. The encoded signal stored in the buffer 90 is output to the terminal 206 in synchronization with this determination result.
【００２４】受信信号に伝送路で誤りが生じていなけれ
ば、符号化信号Ｓ１０４は、第１の符号化信号Ｓ１０１
もしくは第２の符号化信号Ｓ１０２の何れかと等しい。
第２の符号化信号Ｓ１０２は誤り検出符号化器２０にお
いて、生成多項式Ｇ2 （ｘ）を用いて生成したものであ
るのでＧ2 （ｘ）により除算した剰余は零となる。一
方、第１の符号化信号Ｓ１０１は、誤り検出符号化器１
０において生成多項式Ｇ1 （ｘ）を用いて生成したもの
であるのでＧ2 （ｘ）により除算した剰余は一般には零
とならない。Ｇ1 （ｘ）とＧ2 （ｘ）が共通の多項式を
因数として持たなければ、たまたま零となる確率は生成
多項式Ｇ2 （ｘ）の次数に依存し、この場合には概ね２
-16 以下となる。If there is no error in the transmission path of the received signal, the coded signal S104 is the first coded signal S101.
Alternatively, it is equal to any of the second encoded signals S102.
Since the second coded signal S102 is generated by the error detection encoder 20 using the generator polynomial G 2 (x), the remainder divided by G 2 (x) becomes zero. On the other hand, the first coded signal S101 is the error detection encoder 1
Since it is generated by using the generator polynomial G 1 (x) at 0, the remainder divided by G 2 (x) generally does not become zero. If G 1 (x) and G 2 (x) do not have a common polynomial as a factor, the probability that they happen to be zero depends on the order of the generator polynomial G 2 (x), and in this case approximately 2
-16 or less.
【００２５】なお端子２０５から出力される判別結果が
制御信号のときには端子２０６から出力された信号は生
成多項式Ｇ2 （ｘ）による検査をパスしているので伝送
路誤りが無く正しく受信された制御信号である。そして
この制御信号に基づいて制御部（図示省略）において所
定の制御処理が行われる。また、端子２０５の判別結果
がディジタル音声信号のときには音声復号化器（図示省
略）に導かれて生成多項式Ｇ1 （ｘ）により伝送路誤り
の有無がチェックされた後、所定の音声復号処理が行わ
れる。When the discrimination result output from the terminal 205 is a control signal, the signal output from the terminal 206 has passed the inspection by the generator polynomial G 2 (x), so that the control received correctly without any transmission path error. It is a signal. Then, based on this control signal, a control unit (not shown) performs a predetermined control process. Further, when the result of discrimination at the terminal 205 is a digital voice signal, it is guided to a voice decoder (not shown) to check the presence or absence of a transmission path error by the generator polynomial G 1 (x), and then a predetermined voice decoding process is performed. Done.
【００２６】ところで上述した実施例の受信信号判別回
路８０では受信信号の判別に際しては生成多項式Ｇ
2 （ｘ）だけを用いており、Ｇ1 （ｘ）を使用していな
いが、このようにしても正しく判別できる確率が高いこ
とを以下に示す。By the way, in the received signal discriminating circuit 80 of the above-mentioned embodiment, when discriminating the received signal, the generator polynomial G is used.
Although only 2 (x) is used and G 1 (x) is not used, it is shown below that the probability of correct discrimination is high even in this case.
【００２７】さて、受信した信号に誤りが無い場合、本
実施例では第２の符号化信号は正しく判定され、第一の
符号化信号は概ね１−２-16 の確率で正しく判定され
る。もし受信信号判別回路８０がＧ1 （ｘ）を用いて同
様に判別した場合には、第２の符号化信号は概ね１−２
-7の確率で正しく判定され、第１の符号化信号は全て正
しく判定される。従って、本実施例の方が誤判定確率は
極めて小さくなる。受信した信号に誤りがある場合も同
様に本実施例の方が誤判定確率が小さい。If there is no error in the received signal, the second coded signal is correctly determined in this embodiment, and the first coded signal is correctly determined with a probability of 1-2 -16 . If the received signal discrimination circuit 80 makes a similar discrimination using G 1 (x), the second coded signal is approximately 1-2.
It is correctly determined with a probability of -7 , and all the first coded signals are correctly determined. Therefore, the erroneous determination probability is much smaller in this embodiment. Even when the received signal has an error, the probability of erroneous determination is similarly smaller in the present embodiment.
【００２８】多重伝送する信号が音声信号と制御信号で
あるときには音声信号は元々冗長が多いので、制御信号
に誤り検出能力の高い符号を割当てる方が良い。また、
２つの誤り検出用ＣＲＣ信号は相互に識別できれば良
く、６必ずしも誤り検出能力に差がある必要は無い。即
ち、同じ次数であっても異なる２つの多項式を用いれば
良い。When the signals to be multiplexed and transmitted are the voice signal and the control signal, the voice signal originally has a lot of redundancy. Therefore, it is better to assign a code having a high error detecting ability to the control signal. Also,
It suffices that the two error detection CRC signals can be discriminated from each other, and 6 does not necessarily have a difference in error detection capability. That is, two different polynomials may be used even if they have the same degree.
【００２９】[0029]
【発明の効果】以上説明したように本発明の多重信号の
受信装置によれば制御信号やディジタル音声信号の信頼
性を確保するために付加されている誤り検出符号を用い
てどちらの信号であるかを非常に高い信頼度で判別でき
るので余分な識別信号を付加する必要が無い。このため
無線を利用する場合などには無線周波数の有効利用を図
ることができ、その判別誤り率も誤り見逃し確率と同等
であるので、極めて信頼度高く判別できる。As described above, according to the multiple signal receiving apparatus of the present invention, which signal is obtained by using the error detection code added to secure the reliability of the control signal or the digital voice signal. Since it can be discriminated with extremely high reliability, it is not necessary to add an extra identification signal. Therefore, when wireless is used, the wireless frequency can be effectively used, and the determination error rate is also equal to the error-missing probability, so that the determination can be performed with extremely high reliability.
【図１】多重信号を送信する送信装置の構成を示すブロ
ック図である。FIG. 1 is a block diagram showing a configuration of a transmission device that transmits multiple signals.
【図２】本発明の一実施例の受信装置の構成を示すブロ
ック図である。FIG. 2 is a block diagram showing a configuration of a receiving device according to an embodiment of the present invention.
１０、２０…誤り検出符号化器 ３０…選択回路 ４０…パケット信号生成回路 ５０…変調器 ６０…復調器 ７０…パケット分解回路 ８０…受信信号判別回路 ９０…バッファ 10, 20 ... Error detection encoder 30 ... Selection circuit 40 ... Packet signal generation circuit 50 ... Modulator 60 ... Demodulator 70 ... Packet decomposition circuit 80 ... Received signal discrimination circuit 90 ... Buffer
Claims (2)
それぞれ、第１の誤り検出符号と前記第１の誤り検出符
号よりも信頼度の高い第２の誤り検出符号とを付加して
送信された信号を受信する受信装置であって、 前記第２の誤り検出符号によって前記送信された信号の
誤り検出を行う誤り検出手段と、 前記誤り検出手段によって誤り検出を実行した結果、誤
りが無かった場合には前記第２の情報信号を受信してい
ると判定し、誤りがあった場合には前記第１の情報信号
を受信していると判定する受信信号判定手段とを具備し
た受信装置。1. A first information signal and a second information signal,
Receiving devices that receive signals transmitted by adding a first error detection code and a second error detection code having a higher reliability than the first error detection code, respectively. Error detecting means for detecting an error in the transmitted signal by means of an error detecting code; and, as a result of performing error detection by the error detecting means, the second information signal is received if there is no error. A receiving device comprising: a received signal determining means for determining that the first information signal is being received if there is an error.
生成多項式の次数は前記第１の誤り検出符号を生成する
ための生成多項式の次数より高いことを特徴とする請求
項１記載の受信装置。2. The degree of a generator polynomial for generating the second error detecting code is higher than the degree of a generator polynomial for generating the first error detecting code. Receiver.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP34658491A JPH05183531A (en) | 1991-12-27 | 1991-12-27 | Receiver |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP34658491A JPH05183531A (en) | 1991-12-27 | 1991-12-27 | Receiver |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH05183531A true JPH05183531A (en) | 1993-07-23 |
Family
ID=18384412
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP34658491A Withdrawn JPH05183531A (en) | 1991-12-27 | 1991-12-27 | Receiver |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH05183531A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004537241A (en) * | 2001-07-30 | 2004-12-09 | シーメンス アクチエンゲゼルシヤフト | How to support multiple checksum algorithms in a network node |
-
1991
- 1991-12-27 JP JP34658491A patent/JPH05183531A/en not_active Withdrawn
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004537241A (en) * | 2001-07-30 | 2004-12-09 | シーメンス アクチエンゲゼルシヤフト | How to support multiple checksum algorithms in a network node |
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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: 19990311 |