JPS617744A - Privacy communication device - Google Patents

Privacy communication device

Info

Publication number
JPS617744A
JPS617744A JP59128713A JP12871384A JPS617744A JP S617744 A JPS617744 A JP S617744A JP 59128713 A JP59128713 A JP 59128713A JP 12871384 A JP12871384 A JP 12871384A JP S617744 A JPS617744 A JP S617744A
Authority
JP
Japan
Prior art keywords
random number
transmission
state
signal
communication device
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.)
Granted
Application number
JP59128713A
Other languages
Japanese (ja)
Other versions
JPH0683200B2 (en
Inventor
Yoshihiko Akaiwa
芳彦 赤岩
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.)
NEC Corp
Original Assignee
NEC Corp
Nippon Electric Co 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 NEC Corp, Nippon Electric Co Ltd filed Critical NEC Corp
Priority to JP59128713A priority Critical patent/JPH0683200B2/en
Publication of JPS617744A publication Critical patent/JPS617744A/en
Publication of JPH0683200B2 publication Critical patent/JPH0683200B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04K—SECRET COMMUNICATION; JAMMING OF COMMUNICATION
    • H04K1/00—Secret communication
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
    • H04L9/06—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols the encryption apparatus using shift registers or memories for block-wise or stream coding, e.g. DES systems or RC4; Hash functions; Pseudorandom sequence generators
    • H04L9/065—Encryption by serially and continuously modifying data stream elements, e.g. stream cipher systems, RC4, SEAL or A5/3
    • H04L9/0656—Pseudorandom key sequence combined element-for-element with data sequence, e.g. one-time-pad [OTP] or Vernam's cipher
    • H04L9/0662—Pseudorandom key sequence combined element-for-element with data sequence, e.g. one-time-pad [OTP] or Vernam's cipher with particular pseudorandom sequence generator
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
    • H04L9/12—Transmitting and receiving encryption devices synchronised or initially set up in a particular manner

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Computer Security & Cryptography (AREA)
  • Bidirectional Digital Transmission (AREA)
  • Transmission Systems Not Characterized By The Medium Used For Transmission (AREA)

Abstract

PURPOSE:To prevent the deterioration of tone quality in semi-duplex communication, by necessarily changing privacy parameters at the pause of alternately exchanged conversations. CONSTITUTION:When the communication device at the left side starts transmission, a transmission/reception change-over controlling signal inputted in an input terminal 161 is changed from a low order to a high order and a random number generation controlling circuit 191 generates a clock pulse, and then, the state of a random number generating circuit 181 is changed by one step and becomes equal to the state of the random number generating circuit 192 at the receiving side. Sound signals are transmitted from a transmitter 121 after passing through a privacy transmitter 111. Since the states of the circuits 191 and 192 are equal to each other, sound signals, in which privacy is properly decoded, and obtained at an output terminal 152. When the transmission is stopped thereafter, the transmission/reception change-over controlling signal is changed from the high order to the low order and the state of the circuit 1 is further advanced by one step. Then the communication device at the right side starts transmission and the communication device at the left side makes receiving operations.

Description

【発明の詳細な説明】 Ｃ産業上の利用分野） 本発明は、会話の秘密性を守る秘話通信装置で特に半二
重通信装置に使用される秘話装置に関するＯ （従来技術とその問題点） 秘話通信装置の特性のうちで、秘話強度と音質は重要な
問題である。秘話強度け、秘話変換パラメータを時間的
に変化させることによって高めることができる。しかし
従来の秘話通信装置ではこのパラメータを周期的に変化
させていたために変化のたびに切シ換え雑音が発生し、
音質が劣化するという問題があった。[Detailed Description of the Invention] C. Field of Industrial Application) The present invention relates to a confidential communication device that protects the confidentiality of conversations, and particularly relates to a confidential communication device used in a half-duplex communication device. (Prior art and its problems) Among the characteristics of a confidential communication device, confidential communication strength and sound quality are important issues. The strength of secret speech can be increased by temporally changing the secret speech conversion parameter. However, in conventional confidential communication devices, this parameter is changed periodically, so switching noise occurs every time there is a change.
There was a problem that the sound quality deteriorated.

（発明の目的） 本発明の目的は、秘話変換パラメータを切シ換えても、
音質の劣化がない秘話通信装置を提供することにある。(Object of the invention) The object of the invention is that even if the secret conversion parameter is changed,
To provide a confidential communication device with no deterioration in sound quality.

（発明の構成） 本発明によれば、半二重通信において用いられる秘話通
信装置であって、送信信号を後記秘話変換パラメータ信
号に応じて秘話変換し送信する送信手段と、゛秘話変換
がなされた信号を受信し後記秘話変換パラメータ信号に
応じて秘話逆変換する受信手段と、前記牛２重通信にお
ける通信の方向を切換える切換信号を発生する切換信号
発生手段と、、該発生手段より切換信号が入力される毎
に状態’ｔｌステップ変化させることによシ出力乱数を
変化させ秘話変換パラメータ信号として前記送信手段及
び前記受信手段へ供給する乱数発生手段と、通信を開始
するに先立って前記乱数発生手段の状態を初期化させる
初期化手段とから少なくとも構成されることを特徴とす
る秘話通信装置が得られる０ （実施例） 本発明は、半二重通信において、会話が交互に行われる
ことに着目して、秘話パラメータの変化を必らず会話の
切れ目に行うことで音質の劣化を防ぐものである。(Structure of the Invention) According to the present invention, there is provided a confidential communication device used in half-duplex communication, which includes a transmitting unit that converts a transmission signal into a confidential communication according to a confidential conversion parameter signal described later and transmits the confidential communication, receiving means for receiving a signal and inversely converting the confidential message in accordance with a secret conversion parameter signal described later; switching signal generating means for generating a switching signal for switching the communication direction in the cow duplex communication; and a switching signal generating means for generating a switching signal from the generating means. Random number generating means changes the output random number by changing the state 'tl step every time ``tl'' is input, and supplies the random number to the transmitting means and the receiving means as a secret conversion parameter signal; A confidential communication device is obtained which is characterized in that it is constituted of at least an initializing means for initializing the state of the generating means (Embodiment) The present invention provides a device for communicating in half-duplex communication in which conversations are carried out alternately. Focusing on this, the system prevents deterioration of sound quality by always changing the confidential conversation parameters at the breaks in the conversation.

本発明の実施例を第１図に示すロ入力端子１０１よ少入
力される送信音声信号は秘話送信装置１１１によ）秘話
を施されたのち、送信機１２１よル送信される。この信
号は受信機１３２によシ受信されたのち、秘話受信装置
１４２で秘話が解かれ、音声出力端子１５２に送信音声
信号が得られる。同様に、入力端子１０２よ少入力され
る送信音声信号は、秘話送信装置１１２によシ秘話を施
されたのち、送信機１２２よシ送信され、受信機１３１
で受信されたのち、秘話受信装置１４１で秘話が解かれ
、音声出力端子１５１に送信音声信号が得られる。ここ
で、通信は、会話を交互に行う、半二重通信モードで行
われる。送信と受信を切り換える制御信号は入力端子１
６１および１６２より入力される。この送受信制御信号
は通常妥イクに付加されている押ボタンによって発生さ
れる口これらの制御信号の状態は例えば第２図に示すよ
うになる。同図（ａＬ　（ｂ）はそれぞれ入力端子１６
１　、　１６２に入力される送受信切多換え制御信号の
状態を示す。高い方の信号状態（ＨＩ　ＧＨ）は送信状
態を低い方の信号状態（ＬＯＷ）は受信状態を示すもの
としよう。第２図によれば、時刻りから第１図の左側の
通信機から送信を始めて、交互に送信を行ったのち、時
刻１．に通信を終えたこと金示している。送信および受
信の切ル換えは受信時に送信機の出力を断にすることに
よって行われる。An embodiment of the present invention is shown in FIG. 1. (b) A transmission audio signal inputted to an input terminal 101 is subjected to secrecy by a secrecy transmitting device 111, and then transmitted from a transmitter 121. After this signal is received by the receiver 132, the confidential message is decrypted by the confidential message receiving device 142, and a transmitted audio signal is obtained at the audio output terminal 152. Similarly, a transmission audio signal inputted to the input terminal 102 is subjected to confidential communication by the confidential communication transmitting device 112, and then transmitted by the transmitter 122, and then transmitted to the receiver 131.
After receiving the message, the confidential message is decrypted by the confidential message receiving device 141, and a transmitted audio signal is obtained at the audio output terminal 151. Here, communication takes place in half-duplex communication mode, with alternating conversations. The control signal for switching between transmission and reception is input terminal 1.
It is input from 61 and 162. These transmission/reception control signals are usually generated by pushbuttons which are appropriately added.The state of these control signals is, for example, as shown in FIG. 2. The same figure (aL (b) is the input terminal 16
1 and 162 show the states of the transmission/reception switching control signals input to the terminals 1 and 162. Let us assume that the higher signal state (HIGH) indicates the transmitting state and the lower signal state (LOW) indicates the receiving state. According to FIG. 2, transmission starts from the communication device on the left side of FIG. Kim indicates that the communication has ended. Switching between transmission and reception is performed by turning off the output of the transmitter during reception.

秘話送信機および秘話受信機は、秘話操作において、パ
ラメータが変化できるものであればどのようなものでも
よい。例えば、音声帯域を数個の帯域に分割して入れ換
える、帯域分割入れ換え方式などが考えられる。このと
き、帯域の入れ換え方は多数の種類がちシ、これが秘話
パラメータとなる。この秘話パラメータは乱数発生回路
１８１および１８２よシ発生される。乱数発生回路１８
１　、１８２は乱数発生制御回路１９１および１９２に
よシ制御される。The secret message transmitter and the secret message receiver may be of any type as long as the parameters can be changed in the secret message operation. For example, a band division/exchange method may be used in which the audio band is divided into several bands and exchanged. At this time, there are many ways to switch bands, and this becomes a secret parameter. This confidential parameter is generated by random number generation circuits 181 and 182. Random number generation circuit 18
1 and 182 are controlled by random number generation control circuits 191 and 192.

乱数発生回路はクロックパルスが入力されるたびに状態
が１ステツプだけ変化するいわゆる順予回路であればど
のようなものでもよい。第３図は２値乱数発生回路とし
てよく知られている回路を示すものである。回路３０３
〜３０８はシフトレジスタであり、入力端子３０１よシ
クロツク信号を入力されるたびに、シフトレジスタの各
段の内容は次の段にシフトされる。回路３０９は排他的
論理和回路である。クロックパルスを次々と入力するこ
とによル、シフトレジスタの状態はランダムに変化する
。本発明では、シフトレジスタの段である３０３、　３
０４．　３０５の出力全出力端子３１０に出力するもの
とする０出力端子３１０は８とおシの組み合わせ金与え
ることができ、これを秘話パラメータとして使用する。The random number generation circuit may be of any type as long as it is a so-called sequential circuit whose state changes by one step each time a clock pulse is input. FIG. 3 shows a well-known circuit as a binary random number generation circuit. circuit 303
308 are shift registers, and each time a cyclic signal is inputted from the input terminal 301, the contents of each stage of the shift register are shifted to the next stage. Circuit 309 is an exclusive OR circuit. By inputting clock pulses one after another, the state of the shift register changes randomly. In the present invention, the stages 303 and 3 of the shift register are
04. The output of 305 is to be output to the full output terminal 310. The 0 output terminal 310 can be given a combination of 8 and oshi, and this is used as a secret parameter.

第１図に示した乱数発生回路１７１、　１７２の出力が
大きな線で描かれているのは、上のように秘話パラメー
タの値が多数とり得ることを示すためである。第３図に
おいて、入力端子３０２は初期化信号入力端子であシ、
この端子に初期化信号が入力されると、各レジスタの内
容が初期値に設定される。The reason why the outputs of the random number generation circuits 171 and 172 shown in FIG. 1 are drawn with large lines is to show that the secret parameter can take many values as shown above. In FIG. 3, the input terminal 302 is an initialization signal input terminal;
When an initialization signal is input to this terminal, the contents of each register are set to initial values.

初期化信号およびクロックパルス信号は、第４図に示し
た乱数発生制御回路で発生される。初期化信号は入力端
子４２１に入力され、パルス信号発生回路４２３によ少
パルスが発生され、初期化信号パルスとして出力端子４
０２に出力される。初期化信号パルスは同時に遅延回路
４２４を通ったのちＡＮＤゲート４２６に入力される。The initialization signal and clock pulse signal are generated by the random number generation control circuit shown in FIG. The initialization signal is input to the input terminal 421, a small pulse is generated by the pulse signal generation circuit 423, and the initialization signal is output to the output terminal 4 as the initialization signal pulse.
02. The initialization signal pulse simultaneously passes through delay circuit 424 and is then input to AND gate 426 .

ＡＮＤゲート４２６の他方の入力はスイッチ回路４２５
に接続されている。The other input of the AND gate 426 is the switch circuit 425
It is connected to the.

スイッチ回路４２５はスイッチボタン４２２によって、
ゲート回路４２６０入力を接地あるいは開放とすること
によシ、遅延回路４２４の出力パルスの通過あるいは阻
止を行う。スイッチボタン４２２は最初に送信する側に
おいてはスイッチ回路４２５ｔ−接地する側（Ａモード
）を選択し最初に受信する側においてはスイッチ回路４
２５を開放する側（Ｂモード）を選択する。したがって
、最初に受信する側では、初期値信号を入力すると、初
期化パルス信号は出力端子４０１とともにＡＮＤゲート
４２６およびＯＲゲートヲ通って、クロックパルス信号
出力端子４０２に出力される。このようにすることによ
って、初期値化全行った直後、受信側の乱数発生回路の
状態は送信側の乱数発生回路の状態よシもｌステップだ
け先に進んだ状態になっている〇 送受信切シ換え信号は入力端子４２８に入力され、その
状態が変化するたびにパルス発生回路にょシ、クロック
パルスが発生され、ＯＲグー）　４２７　ｆｆｉ通った
のち、出力端子４０１に出力される。出力端子４０１に
出力されるクロックパルスは当然第３図のクロック入力
端子３０１に入力される。出力端子４０２に出力される
初期化パルス信号は第３図の入力端子３０２に入力され
る。The switch circuit 425 is activated by the switch button 422.
By grounding or opening the gate circuit 4260 input, the output pulse of the delay circuit 424 is passed or blocked. The switch button 422 selects the switch circuit 425t-grounding side (A mode) on the first transmitting side, and selects the switch circuit 425t on the first receiving side.
Select the side (B mode) to open 25. Therefore, on the first receiving side, when the initial value signal is input, the initialization pulse signal passes through the output terminal 401, the AND gate 426, and the OR gate, and is output to the clock pulse signal output terminal 402. By doing this, immediately after all initialization is performed, the state of the random number generation circuit on the receiving side is l steps ahead of the state of the random number generation circuit on the sending side. The switching signal is input to the input terminal 428, and each time its state changes, a clock pulse is generated by the pulse generation circuit, and after passing through the OR gate (427 ffi), it is output to the output terminal 401. The clock pulse outputted to the output terminal 401 is naturally inputted to the clock input terminal 301 in FIG. The initialization pulse signal output to the output terminal 402 is input to the input terminal 302 in FIG.

例として、第２図に示したように、第１図に示した左側
の通信装置が時刻ｔ、から送信を開始する場合を考える
ことにしよう。その前に、左側の通信機はＡモードで右
側の通信機はＢモードで初期化が行われておシ、受信側
（右側）の乱数発生回路１８２の状態は初期状態の次の
状態になっていることが必要である０左側の通信機が送
信を始め〆たとたんに、入力端子１６１に入力される送
受借切シ換え制御信号がＬＯＷからＨＩＧ）（に変化し
、乱数発生制御回路１９１がクロックパルスヲ発生し、
乱数発生回路の状態が１ステツプだけ変化、受信側の乱
数発生回路１９２の状態と等しくなる。音声信号は秘話
送信機１１１を通ったのち、送信機１２１よシ送信され
る。送信および受信の乱数発生回路１９１および１９２
の状態が等しいので、出力端子１５２には正しく秘話が
解かれた音声信号が得られる。送信を止めると送受借切
シ換え信号ＨＩＧＨからＬＯＷに変化し、乱数発生回路
１８１の状態がさらに１ステップ進む。今度は右側の通
信機が送信をはじめるために、入力端子１６２に入力さ
れる送受借切シ換え信号がＬＯＷからＩ（ＩＧＨＫ変化
し、乱数発生回路１８２の状態が１ステップ進み、受信
側の乱数発生回路１８１の状態と等しくなるので正常な
秘話通信が行える。以後同様にして通信を続けることが
できる０第３者が通信を傍受しようとしても、乱数発生
回路の状態を知ることができないかぎシ、正常な受信を
行うことはできない。As an example, let us consider a case where the communication device on the left side of FIG. 1 starts transmitting at time t, as shown in FIG. Before that, the communication device on the left side has been initialized in A mode and the communication device on the right side has been initialized in B mode, and the state of the random number generation circuit 182 on the receiving side (right side) is the next state after the initial state. As soon as the communication device on the left side starts transmitting, the transmission/reception switching control signal input to the input terminal 161 changes from LOW to HIG, and the random number generation control circuit 191 generates a clock pulse,
The state of the random number generation circuit changes by one step and becomes equal to the state of the random number generation circuit 192 on the receiving side. After the voice signal passes through the confidential transmitter 111, it is transmitted to the transmitter 121. Transmission and reception random number generation circuits 191 and 192
Since the states are the same, a correctly decrypted audio signal is obtained at the output terminal 152. When the transmission is stopped, the transmission/reception switching signal changes from HIGH to LOW, and the state of the random number generation circuit 181 advances one step further. This time, in order for the communication device on the right to start transmitting, the transmission/reception switching signal input to the input terminal 162 changes from LOW to I (IGHK), the state of the random number generation circuit 182 advances by one step, and the random number on the receiving side changes. Since the state is equal to the state of the random number generation circuit 181, normal secret communication can be performed.From now on, communication can be continued in the same way. Even if a third party tries to intercept the communication, the state of the random number generation circuit cannot be known. , normal reception cannot be performed.

（発明の効果） 以上の説明から理解できるように、本発明においては、
秘話パラメータの変化は、会話の切れ目に行われるため
に、パラメータの変化による音質の劣化が起らないとい
う効果がある。もちろん、秘話パラメータを時間的に変
化させない場合にもこのような音質の劣化はないけれど
も、本発明は、このような方式に比べて秘話強度が高ま
る効果があるＯ(Effect of the invention) As can be understood from the above explanation, in the present invention,
Since the confidential conversation parameters are changed at breaks in the conversation, there is an advantage that the sound quality does not deteriorate due to parameter changes. Of course, this kind of deterioration in sound quality does not occur even when the secret message parameter is not changed over time, but the present invention has the effect of increasing the strength of the secret message compared to such a method.

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

第１図は本発明の実施例を示すブロック図、第２図は本
発明における送受借切シ換信号の状態を示す図、第３図
は本発明に使用される乱数発生回路の例を示すブロック
図、第４図は本発明に使用される乱数発生制御回路のプ
ロ、り図である。 これらの図において、　１０１．　１０２は送信音声信
゛号入力端子、１１１．　１１２は秘話送信機、１２１
　、１２２は送信機、１３１．　１３２は受信機、１４
１．　１４２は秘話受信機、１５１．　１５２は受信音
声信号出方端子、１６１、　１６２は送受借切シ換え制
御信号、１７１．　１７２は初期化信号入力端子、　１
８１．　　ｉ８２は乱数発生回路、１９１．　１９２は
乱数発生制御回路、３０１はクロックパルス信号入力端
子、３０２は初期化信号入力端子、３０３〜３０８１ｉ
Ｖ７）　ｖジ／（／、３０９は排他的論理和回路、３１
０は秘話パラメータ出力端子、４０１はクロックパルス
信号出方端子、４０２は初期化信号出力端子、４２１は
初期化信号入力端子、４２２はスイッチボタン、　４２
３．　４２９はパルス信号発生回路、４２４け遅延回路
、４２５はスイッチ回路、４２６はＡＮＤゲート、４２
７はＯＲゲート、４２８は送受信切シ換え制御信号入力
端子であ４る。FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a diagram showing the state of a transmission/reception switching signal in the present invention, and FIG. 3 is a diagram showing an example of a random number generation circuit used in the present invention. FIG. 4 is a block diagram of a random number generation control circuit used in the present invention. In these figures, 101. 102 is a transmission audio signal input terminal; 111. 112 is a secret transmitter, 121
, 122 is a transmitter, 131 . 132 is a receiver, 14
1. 142 is a secret receiver, 151. 152 is a received audio signal output terminal; 161 and 162 are transmission/reception switching control signals; 171. 172 is an initialization signal input terminal, 1
81. i82 is a random number generation circuit, 191. 192 is a random number generation control circuit, 301 is a clock pulse signal input terminal, 302 is an initialization signal input terminal, 303 to 3081i
V7) vji/(/, 309 is exclusive OR circuit, 31
0 is a secret parameter output terminal, 401 is a clock pulse signal output terminal, 402 is an initialization signal output terminal, 421 is an initialization signal input terminal, 422 is a switch button, 42
3. 429 is a pulse signal generation circuit, 424 delay circuits, 425 is a switch circuit, 426 is an AND gate, 42
7 is an OR gate, and 428 is a transmission/reception switching control signal input terminal.

Claims (1)

【特許請求の範囲】[Claims] 半２重通信において用いられる秘話通信装置であって、
送信信号を後記秘話変換パラメータ信号に応じて秘話変
換し送信する送信手段と、秘話変換がなされた信号を受
信し後記秘話変換パラメータ信号に応じて秘話逆変換す
る受信手段と、前記半２重通信における通信の方向を切
換える切換信号を発生する切換信号発生手段と、該発生
手段より切換信号が入力される毎に状態を１ステップ変
化させることにより出力乱数を変化させ秘話変換パラメ
ータ信号として前記送信手段及び前記受信手段へ供給す
る乱数発生手段と、通信を開始するに先立って前記乱数
発生手段の状態を初期化させる初期化手段とから少なく
とも構成されることを特徴とする秘話通信装置。A confidential communication device used in half-duplex communication,
a transmitting means for encrypting a transmission signal according to a secret speech conversion parameter signal described later and transmitting it; a receiving means for receiving the signal after the secret speech conversion and inversely converting the secret speech according to a secret speech conversion parameter signal described later; and the half-duplex communication. switching signal generating means for generating a switching signal for switching the direction of communication; and the transmitting means for changing the output random number by changing the state by one step each time the switching signal is inputted from the generating means as a secret conversion parameter signal. A confidential communication device comprising at least a random number generating means for supplying the receiving means to the receiving means, and an initializing means for initializing the state of the random number generating means before starting communication.
JP59128713A 1984-06-22 1984-06-22 Confidential communication device Expired - Lifetime JPH0683200B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP59128713A JPH0683200B2 (en) 1984-06-22 1984-06-22 Confidential communication device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP59128713A JPH0683200B2 (en) 1984-06-22 1984-06-22 Confidential communication device

Publications (2)

Publication Number Publication Date
JPS617744A true JPS617744A (en) 1986-01-14
JPH0683200B2 JPH0683200B2 (en) 1994-10-19

Family

ID=14991587

Family Applications (1)

Application Number Title Priority Date Filing Date
JP59128713A Expired - Lifetime JPH0683200B2 (en) 1984-06-22 1984-06-22 Confidential communication device

Country Status (1)

Country Link
JP (1) JPH0683200B2 (en)

Also Published As

Publication number Publication date
JPH0683200B2 (en) 1994-10-19

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