JPS61260731A - Privacy telephone set - Google Patents
Privacy telephone setInfo
- Publication number
- JPS61260731A JPS61260731A JP10218585A JP10218585A JPS61260731A JP S61260731 A JPS61260731 A JP S61260731A JP 10218585 A JP10218585 A JP 10218585A JP 10218585 A JP10218585 A JP 10218585A JP S61260731 A JPS61260731 A JP S61260731A
- Authority
- JP
- Japan
- Prior art keywords
- frequency
- spectrum
- adder
- signal
- local frequency
- 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
Links
Abstract
Description
【発明の詳細な説明】
(産業上の利用分野)
本発明は秘話装置、殊にスペクトル反転回転形秘話装置
の改良に関する。DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to an improved encrypted communication device, particularly to a spectrum inversion rotary encrypted communication device.
(従来技術)
通信内容の秘密保持方法として従来から種々の秘話方式
及び秘話装置が提案されているが。(Prior Art) Various confidential communication methods and confidential communication devices have been proposed as methods for maintaining the confidentiality of communication contents.
その一つに伝送すべき信号の周波数スペクトルを所要数
の区間に分割して並べ換え或は反転せしめ反転(ロ)転
スペクトルとして送信するものがある。One of these methods is to divide the frequency spectrum of a signal to be transmitted into a required number of sections, rearrange or invert it, and transmit it as an inverted spectrum.
このスペクトル反転回転方式は他のものに比較して復調
音質に優れかつ(ロ)路の実現が容易である反面単純な
反転回転方式では秘話強IWがやや低い欠点及びこれを
実現する装置に製作困難な帯域フィルタを要すると云う
問題があった。This spectrum inversion rotation method has superior demodulated sound quality compared to other methods, and it is easy to realize the (b) route, but on the other hand, the simple inversion rotation method has a disadvantage that the secret strength IW is slightly low, and a device to realize this has been manufactured. The problem was that it required a difficult bandpass filter.
このため従来例えば特願昭59年1i21148(秘話
装置! )或は特願昭59−44141(秘話方法及び
装置li)に示されるように、スペクトルの反転周波数
位置又は回転組合せ?任意にf更すると共に帯域フィル
タに代え比較的製作容易な低域フィルタで代用しうるよ
うにすることによって秘話性を高めかつコスト低減をは
かった方法が提案されている。For this purpose, conventionally, for example, as shown in Japanese Patent Application No. 1121148 of 1982 (Secret Communication Device!) or Japanese Patent Application No. 59-44141 (Secret Communication Method and Apparatus li), there has been proposed an inversion frequency position or rotation combination of the spectrum. A method has been proposed in which f is changed arbitrarily and a low-pass filter, which is relatively easy to manufacture, is substituted for the bandpass filter, thereby increasing confidentiality and reducing costs.
本発明の理Mk容易ならしめるために以下に前記従来方
法について少しく説明する。In order to simplify the process of the present invention, the conventional method will be briefly explained below.
第2図(al及び(blは従来の反転回転形秘話装置を
示すブロック図及びその動作を説明する信号のスペクト
ル図である。FIG. 2 (al and (bl) are a block diagram showing a conventional inversion-rotation type private communication device and a signal spectrum diagram explaining its operation.
先づ第2図(alに示した装置構成を簡単に説明すれば
、同図(b)の(イ)に示す如く最高周波数をfmに制
限した音…(iけ1i2分岐し一方を直接加算器2の一
入力端に、又他万全ローカル周波砂kfmとし混合出力
のうち両者の和のみを出力する周波政変換回路3に介し
て前記加1!器2の他の入力端に入力し該加算器の出力
端に?p、2図(blの(ロ)に示す如く前記音声信号
1を周波数をンフトに隣接して2つ並べたスペクトルを
得る。First, to briefly explain the device configuration shown in Figure 2 (al), as shown in (a) of Figure 2(b), the highest frequency is limited to fm... (i, 1, 2 branches and one is added directly. The input terminal of the adder 2 is input to one input terminal of the adder 2, and the other input terminal of the adder 1! At the output end of the adder, as shown in (b) of Figure 2, a spectrum of the audio signal 1 is obtained in which two frequencies are arranged adjacent to each other.
更に、この信号を2分岐し、2つの乗算器MULT I
、!: MIJLT 2 トノ間に低域汐1e器1.
. P F +全挿入した第1の直列1川路ルートと、
同様に2つの乗算器M IJ L ’[” 3とMIJ
LT4との間に第2の低域FJe器L P F Zを挿
入した第2の直列1川路ルートの夫々を介して第2の加
算器4に入力すると共に前記第1の直列回路ルートに属
する乗算器には90°移相器PS+及びPS2を介し文
筆2の直列回路ルートの乗算器には直接に発振器08C
1及びO8C2出力をローカル周波数として夫々の前置
乗算器と後置乗算器に共通に印加することによって前記
第2の加算器4の出力に第2図(bl(ハ)に示す如く
反転回転した音声スペクトルを得るよう構成したもので
ある。Furthermore, this signal is branched into two, and two multipliers MULT I
,! : MIJLT 2 Low range 1e unit between the tonneau 1.
.. P F + fully inserted first series one river route,
Similarly, two multipliers M IJ L '[" 3 and MIJ
It is input to the second adder 4 through each of the second series one-way circuit routes in which a second low-frequency FJe circuit LPFZ is inserted between the circuit and the LT4, and also belongs to the first series circuit route. The multiplier is connected to the 90° phase shifter PS+ and PS2, and the oscillator 08C is directly connected to the multiplier in the series circuit route of the writing brush 2.
1 and O8C2 outputs as local frequencies are commonly applied to the respective pre-multipliers and post-multipliers, so that the output of the second adder 4 is inverted and rotated as shown in FIG. It is configured to obtain a voice spectrum.
このように構成すれば製作困難な帯域P波器を不要とす
ることができるが、良に前記ローカル発揚器O8C+又
け08C2のいづれか一方にコード発生器を付加し所定
の規則に従ってローカル周波数’tf化せしめたのち所
望の通信回線全弁して伝送すればより一層秘話性を高め
ることができる。伺これ全受信する際には前記コード化
規則と同期をとりつつローカル発振器を制御して復調す
れば原音声信号を復元することができる。With this configuration, it is possible to eliminate the need for a band P-wave generator that is difficult to manufacture, but it is better to add a code generator to either one of the local oscillators O8C+ or 08C2 and adjust the local frequency 'tf according to a predetermined rule. Secrecy can be further improved by transmitting the information over all desired communication lines after the information is transcribed. When receiving all the signals, the original audio signal can be restored by controlling the local oscillator and demodulating it in synchronization with the encoding rule.
しかしながら、このようなスペクトル反転回転処理はア
ナログ信号そのままでも可能であるが、これに用いる回
路素子は一般に大型かつ複雑となるから一層アナログ/
デジタル変換(AT)変換)後デジタル処理するのが通
常であり。However, although such spectrum inversion/rotation processing is possible with analog signals as they are, the circuit elements used for this are generally large and complex, so analog/
It is usual to perform digital processing after digital conversion (AT conversion).
斯くすることによって装置自体全簡素化することが行な
われる。By doing so, the device itself can be completely simplified.
然かるに、上述した従来の秘話装置はr波器3個1乗算
器5個及び加減算器2個1合計10個の演算素子を最低
必要とするからこれをデジタル化する場合種々の不具合
を生ずる。However, since the above-mentioned conventional secret communication device requires a minimum of 10 arithmetic elements, including 3 R wave units, 5 multipliers, and 2 adders/subtractors, various problems occur when digitizing this device. .
即ち、一般にデジタル演算に於いてデータを表示するピ
ット長は有限であるから該ビット長が短くなるほど多く
の丸め誤差(切捨て誤差とも云う)を生じ、あたかも雑
音が混入した如く作用する。この不具合は固定小計点演
算の場合著しく、従って用いるべき演算要素は出来得る
限り少ない方が望ましい。That is, since the pit length for displaying data in digital calculations is generally finite, the shorter the bit length, the more rounding errors (also referred to as truncation errors) occur, acting as if noise were mixed in. This problem is significant in the case of fixed subtotal calculations, and therefore it is desirable to use as few calculation elements as possible.
(発明の目的)
本発明は上述したような従来のスペクトル反転回転形秘
話装置の問題を解決するためになされたものであって、
前記従来掃案された秘話装置の特長を生かしつつ演算要
素を減少せしめ。(Object of the Invention) The present invention was made in order to solve the problems of the conventional spectrum inversion rotation type confidential communication device as described above.
The number of calculation elements is reduced while taking advantage of the features of the conventional private conversation device.
デジタル処理を行うのに適した秘話装置を提供すること
を目的とする。The purpose of the present invention is to provide a confidential communication device suitable for performing digital processing.
(発明の概要)
この目的のため本発明では、所要の帯域制限を受けた音
声スペクトル信号全2分岐しその一方全、ローカル周波
数′ff:fmとし混合出力のうち低域成分を抽出する
よう構成した筆1の周波数変換回路と、ローカル周波数
kfKとした混合−1路とからなる第1のルートを介し
て加算回路の一入力端に入力すると共に、前記2分岐し
た音声スペクトル成分の他方ケローカル周波数> f
K 十f mとしその混合成分のうちから高域成分のみ
全抽出する高域fe器とからなる駆2の周波数変換回路
とローカル周波数’(i=、fmとする第2の混合回路
とを直列接続してなる第2のルートを介して前記加算器
のもう一方の入力端に人力し、該加算器出力のうちから
fm以下の成分のみを抽出し秘話出力とするよう構成す
る。(Summary of the Invention) For this purpose, the present invention is configured to branch all audio spectrum signals into two that have received the required band limit, and extract the low-frequency components from the mixed output at local frequencies 'ff: fm. It is inputted to one input terminal of the adding circuit through the first route consisting of the frequency conversion circuit of brush 1 and the mixing path with the local frequency kfK, and the local frequency of the other of the two branched audio spectrum components is inputted to one input terminal of the addition circuit. >f
The frequency conversion circuit of driver 2, which consists of a high-frequency FE device that extracts all high-frequency components from the mixed components of K ten f m, and a second mixing circuit with a local frequency '(i=, fm) are connected in series. The configuration is such that a human input is input to the other input terminal of the adder through a second route formed by the connection, and only the components below fm are extracted from the output of the adder and output as a secret speech output.
又更には、前記ローカル周波数のうちf Kに関する信
号を時間的に不規則に変化するコード化信号によって制
御することによって秘話性をより高くするよう構成する
。Furthermore, the communication communication apparatus is configured to further enhance privacy by controlling a signal related to fK among the local frequencies by a coded signal that changes irregularly over time.
(実施例)
以下本発明を図示した実施例に基づいて詳細に説明する
。(Example) The present invention will be described in detail below based on an illustrated example.
第1図(alは本発明の一実施例金示すブロック図であ
る。FIG. 1 is a block diagram showing one embodiment of the present invention.
同図に於いて5は音声入力端であって、核部に同図(b
)(イ)の如く最高周波数をfmに制限した音声信号を
入力し、これを2分岐した一方をローカル周波数として
fmを出力する発振器6の出力を一人力とする乗算器7
のもう一方の入力端に入力すると共に、該乗算器の出カ
km断周波数全fmとする低域P波器8全介して第2の
発振器9の出力fm+fK(0<、fK<fm)k−人
力とする第2の乗算器1oに入力しその混合出力を加算
器11の一方の入力端に接続する。又前記2分した音声
信号の他方はローカル周波数fK全出力する第3の発振
器121r−人力とする第3の乗算器13と遮断周波数
kfmとする高域−波器14とローカル周波数fmk出
カする第4の発振器15の出刃を一方の入力とする第4
の乗算器16とからなる第2のルートを介して前記加算
器11の他方入万端に接続すると共に該加算器11の出
刃f:W断周波周波数mとする低域P波器17に人力し
その出力端に所望の秘話信号全書る如く構成する、
このように構成した秘話装置の入力端5に印加される第
1図+1)l Iイ)に示すような最高周波数がfmと
なる如く帯域制限を受けた音声信号のうち前記第1ルー
トを介して加算器11に至るもののスペクトルは先づ乗
算器71発振器6及び低埴P波器8とからなる第1の周
波数変換回路に於いてローカル周波数fmと混合された
のちfm以下成分のみが抽出されるから第1図(b)(
ロ)に示す如く周波数茎軸を中心に左右対称な反転した
スペクトルとなり、¥に次段の混合回路に於いて周波数
f x + f mの位置までシフトされ同図←→に示
すようなスペクトル信号となって加算器IIに至る。In the same figure, 5 is an audio input terminal, and the core part is shown in the same figure (b
) A multiplier 7 that inputs an audio signal with the highest frequency limited to fm as shown in (a), branches it into two, sets one as the local frequency, and outputs fm as the output of the oscillator 6.
The output of the second oscillator 9 fm+fK (0<, fK<fm) k - input to a second manually powered multiplier 1o and connect its mixed output to one input end of the adder 11; The other half of the audio signal is output from a third oscillator 121r which outputs the full local frequency fK, a human-powered third multiplier 13, a high-frequency wave generator 14 which has a cutoff frequency kfm, and outputs the local frequency fmk. A fourth oscillator whose one input is the blade of the fourth oscillator 15.
It is connected to the other input terminal of the adder 11 via a second route consisting of a multiplier 16, and is manually connected to a low-frequency P wave generator 17 which sets the cutting edge f:W cutoff frequency of the adder 11 to m. It is configured so that all the desired confidential communication signals are written on the output terminal, and the band is set such that the highest frequency as shown in Fig. The spectrum of the limited audio signal that reaches the adder 11 via the first route is first localized in the first frequency conversion circuit consisting of the multiplier 71, the oscillator 6, and the low P wave generator 8. After being mixed with the frequency fm, only the components below fm are extracted, as shown in Figure 1(b).
As shown in (b), the spectrum becomes an inverted spectrum that is symmetrical about the frequency stem axis, and is then shifted to the position of frequency f x + f m in the next mixing circuit, resulting in a spectrum signal as shown in the same figure. and reaches adder II.
一方第2のルートを通る音声信号は同様に第3の乗算器
13に於いてローカル周波数fvcと混合されたのち高
域P波器14によってfm以上の成分のみが抽出される
からそのスペクトルは同図に)となり、更には第4の乗
算器16によってfmと混合され同図(ホ)に示す如き
スペクトルとなって加算器11に至る。On the other hand, the audio signal passing through the second route is similarly mixed with the local frequency fvc in the third multiplier 13, and then only the components higher than fm are extracted by the high-frequency P-wave unit 14, so their spectra are the same. ) is further mixed with fm by the fourth multiplier 16 to form a spectrum as shown in (e) in the figure, which reaches the adder 11.
従って加算器11の出力には前記二つのルート?経た信
号が加算されるがfmvn断周波数周波数低HP波器1
7によってfm以上がカットされるからその出力端には
同図(へ)に示す如くfm以下の周波数であってかっf
Kに於いて反転回転せしめた音声スペクトル信号を得る
ことができる。Therefore, the output of the adder 11 has the above two routes. The passed signals are added, but the fmvn cutoff frequency frequency low HP wave device 1
Since frequencies above fm are cut by 7, the output terminal has frequencies below fm as shown in the same figure (f).
An audio spectrum signal that is inverted and rotated at K can be obtained.
以上の説明から明らかな如く、従来の秘話装置に比べて
乗算器が一つかつ加算器が一つ計二つの演算要素が少な
い構成によって同様の反転回転スペクトル信号を得るこ
とができるから上述したように丸め誤差の減少及び演算
速度向上をはかることができる。As is clear from the above explanation, a similar inverted rotation spectrum signal can be obtained with a configuration that has fewer calculation elements, one multiplier and one adder, compared to the conventional confidential communication device. It is possible to reduce rounding errors and improve calculation speed.
又2本発明に於いても従来装置と同様に前記ローカル周
波数のうちfK?時間的に不規則に変化せしめることに
よって秘話強度を高める操作を併用することも可能であ
り、この場合には受信側に於いて前記不規則変化に同期
してローカル周波数tf化せしめる必要があろう。In addition, in the present invention as well, fK? It is also possible to use an operation to increase the intensity of confidential communication by making the signal change irregularly in time. In this case, it is necessary to synchronize the receiving side with the local frequency tf in synchronization with the irregular change. .
又更に、上述した実施例では送信伸装置を例にとって説
明したが同様の構成によって受信復調装置を実現でき、
この場合は前記第2のローカル周波数Vifm−fKと
すればよい。Furthermore, although the above-mentioned embodiment has been explained by taking the transmitting decompression device as an example, a receiving demodulating device can be realized with a similar configuration.
In this case, the second local frequency Vifm-fK may be used.
従って、同一の装置を送受信装置兼用とする場合は第3
図に示す如く第2のローカル発振周波?efm士fKの
二つに切換えるための制御器18を付加し送信のときけ
fm+fKf又受信の際はfm−、fK’jrローカル
周波数とする如く構成すればよい。Therefore, if the same device is used as a transmitting and receiving device, the third
The second local oscillation frequency as shown in the figure? A controller 18 may be added to switch between efm and fK, and the local frequency may be set to fm+fKf when transmitting, and fm- and fK'jr when receiving.
更には同図中点線で示したように前記制御器に於いてロ
ーカル周波数のうちfKを時間的に不規則に変化するコ
ード化信号を発生し該信号によって第2の発振器9及び
第3の発振器12のfKk制御するよう構成すれば上述
した如くより一層秘話性を高めることができる。Furthermore, as shown by the dotted line in the figure, the controller generates a coded signal that changes fK of the local frequency irregularly over time, and this signal causes the second oscillator 9 and the third oscillator to be activated. If the configuration is configured to perform fKk control of 12, it is possible to further improve confidentiality as described above.
伺9本発明の実施にあたっては上述した例に限定する必
要はなく他の構成2例えば同一ローカル周波数は同一発
振器出力を共用すること。9. In carrying out the present invention, it is not necessary to limit it to the above-mentioned example, and other configurations 2 are possible, for example, the same local frequency may share the same oscillator output.
又は第4の発振器15のfmなる周波数金地のものとす
ることによって音声信号の帯域制限周波数をf更するこ
と等はいづれも自由に設定することができる。更に本発
明全アナログ信号処理装置とすることも可能なること明
らかであろう。Alternatively, by setting the frequency fm of the fourth oscillator 15 to be a gold standard, the band limit frequency of the audio signal can be changed to f, etc., which can be freely set. Furthermore, it will be obvious that the present invention can also be implemented as an all-analog signal processing device.
(発明の効果)
以上説明した如く本発明によれば従来と同一の秘話信号
を得るに際し演算処理要素を減少【7た構成をとるもの
であるから、丸め誤差による雑音を軽減するとともに演
算スピードを早めかつ装置のコスト低減をはかった秘話
装置1をもたらすうえで著効全奏する。(Effects of the Invention) As explained above, according to the present invention, the number of calculation processing elements is reduced when obtaining the same confidential signal as in the past, so noise due to rounding errors is reduced and calculation speed is increased. Moreover, it is highly effective in providing a confidential communication device 1 that reduces the cost of the device.
第1図(a)及び(b)は本発明の一実施例を示すブロ
ック図及びその動作を説明するためのスペクトル図、第
2図(at及び(blは従来の秘話装置を示すブロック
図及びその動作を説明するためのスペクトル図、第3図
は本発明の変形例を示すブロック図である。
5・・・・・・・・・音声信号入力端、 6,9.
12及び15・・・・・・・・・発揚器、 ?、1
0.13及び16・・・・・・・・・乗算器、 8及
び17・・・・・・・・・低域P波器14・・・・・・
・・・高域P波器、 11・・・・・・・・・加算器
、 18・・・・・・・・・制御器。FIGS. 1(a) and (b) are a block diagram showing an embodiment of the present invention and a spectrum diagram for explaining its operation, and FIGS. A spectrum diagram for explaining the operation, and FIG. 3 is a block diagram showing a modified example of the present invention. 5...Audio signal input terminal, 6, 9.
12 and 15......Elevator, ? ,1
0.13 and 16... Multiplier, 8 and 17... Low frequency P wave unit 14...
...High-frequency P-wave unit, 11...Adder, 18...Controller.
Claims (4)
fmとしfm以下の成分を抽出する第1の周波数変換回
路と、ローカル周波数を fm+fK(fm>fK)とした混合回路とを直列接続
した第一のルートに、又他方をローカル周波数をfKと
しfm以上の周波数成分を抽出する第2の周波数変換回
路とローカル周波数をfm′(fm≧fm′)とする第
2の混合回路とを直列接続した第2のルートの夫々を介
したのち両者を加算し該加算信号からfm以下の成分の
みを抽出して所望の信号を得るように構成したことを特
徴とする秘話装置。(1) A first frequency conversion circuit that divides the input signal into two, sets the local frequency of one half to fm, and extracts components below fm, and a mixing circuit that sets the local frequency to fm+fK (fm>fK) is connected in series. On the first route, a second frequency conversion circuit whose local frequency is fK and which extracts frequency components higher than fm, and a second mixing circuit whose local frequency is fm'(fm≧fm') are connected to the first route. A secret communication device characterized in that it is configured to obtain a desired signal by adding the two signals after passing through each of the second routes connected in series, and extracting only the components below fm from the added signal.
又は規則的に0<fK<fmの範囲で変化せしめたこと
を特徴とする特許請求の範囲1項記載の秘話装置。(2) The secret communication device according to claim 1, characterized in that fK of the local frequency is temporally changed irregularly or regularly within a range of 0<fK<fm.
m−fKとすることによって受信側復調装置としたこと
を特徴とする特許請求の範囲1項又は2項記載の秘話装
置。(3) The local frequency in the first mixing circuit is f
3. The confidential communication device according to claim 1 or 2, characterized in that it is used as a reception side demodulation device by using m-fK.
−fKとの2値に切替えることによって同一装置を送信
用と受信用とに兼用したことを特徴とする特許請求の範
囲1項、2項又は3項記載の秘話装置。(4) The frequency of the first mixing circuit is fm+fK and fm
4. A confidential communication device according to claim 1, 2 or 3, characterized in that the same device can be used for both transmission and reception by switching to a binary value of -fK.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP10218585A JPH0630483B2 (en) | 1985-05-14 | 1985-05-14 | Confidential device |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP10218585A JPH0630483B2 (en) | 1985-05-14 | 1985-05-14 | Confidential device |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS61260731A true JPS61260731A (en) | 1986-11-18 |
JPH0630483B2 JPH0630483B2 (en) | 1994-04-20 |
Family
ID=14320607
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP10218585A Expired - Lifetime JPH0630483B2 (en) | 1985-05-14 | 1985-05-14 | Confidential device |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH0630483B2 (en) |
-
1985
- 1985-05-14 JP JP10218585A patent/JPH0630483B2/en not_active Expired - Lifetime
Also Published As
Publication number | Publication date |
---|---|
JPH0630483B2 (en) | 1994-04-20 |
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