JPS61198839A - Privacy call system - Google Patents
Privacy call systemInfo
- Publication number
- JPS61198839A JPS61198839A JP3796185A JP3796185A JPS61198839A JP S61198839 A JPS61198839 A JP S61198839A JP 3796185 A JP3796185 A JP 3796185A JP 3796185 A JP3796185 A JP 3796185A JP S61198839 A JPS61198839 A JP S61198839A
- Authority
- JP
- Japan
- Prior art keywords
- wave
- output
- frequency
- single sideband
- oscillator
- 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
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Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04K—SECRET COMMUNICATION; JAMMING OF COMMUNICATION
- H04K1/00—Secret communication
- H04K1/003—Secret communication by varying carrier frequency at or within predetermined or random intervals
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、音声信号のスペクトラムを変換して通信の相
手以外の者にその通話内容が了解できない様にする秘話
方式の改良に関するものである。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an improvement in a confidential communication system that converts the spectrum of a voice signal so that the contents of the call cannot be understood by anyone other than the person on the other end of the communication. .
例えば、沿岸無線や港内無線によるしｎ時公衆回線のプ
ライバシーの保護や、警察無線等の盗聴防止の為に秘話
方式が用いられているが、回路構成が簡単なものは容易
に盗聴可能であり、複雑なものは盗聴でき難いが装置価
格が高くなる。For example, secret communication methods are used to protect the privacy of public lines such as coast radio and port radio, and to prevent eavesdropping on police radios, etc., but wiretapping is easily possible if the circuit configuration is simple. , Complex data is difficult to eavesdrop on, but equipment costs are high.
そこで、回路構成が簡単で、コストダウンされた秘話方
式が要望されている。Therefore, there is a need for a secret communication system with a simple circuit configuration and reduced costs.
音声信号のスペクトラムを変換させる秘話方式の主なも
のとして、周波数反転方式と帯域分割方式の２つがある
。There are two main types of confidential communication methods for converting the spectrum of an audio signal: a frequency inversion method and a band division method.
前者は音声信号のスペクトラムの高い方の成分を低い方
に、低い方の成分を高い方に変換して通話の秘話性を持
たせる方式である。The former is a method that converts the higher end of the spectrum of the audio signal into the lower end, and the lower end of the spectrum into the higher end, thereby making the call confidential.
後者は音声信号のペクトラムを、例えば０．３〜１．３
３．１．３３〜２．３６．２．３６〜３．４ ＫＨｚの
３つの部分に分割し、各部分の位置を入替えて秘話性を
持たせる方式である。The latter measures the spectrum of the audio signal, for example from 0.3 to 1.3.
This is a method in which the signal is divided into three parts of 3.1.33 to 2.36 and 2.36 to 3.4 KHz and the positions of each part are switched to provide confidentiality.
しかし、前者は回路構成が簡単であるが、秘話性が低く
、後者は秘話性は高いが高性能の帯域通過型ろ波器が必
要となるので装置価格が高くなると云う問題点がある。However, the former has a simple circuit configuration but has low privacy, while the latter has high privacy but requires a high-performance bandpass filter, which increases the cost of the device.
上記の問題点は、送信側では入力された音声信号を送信
側発振器の出力と混合して単側波帯波（以下ＳＳＢ波と
省略する）に変換するＳＳＢ発生部と、該ＳＳＢ発生部
よりの出力をＮ分周して音声帯域内に変換する分周器の
２つの部分、又は該音声信号から抽出された包絡線成分
で副搬送波を変調する変調器と、該変調器の出力と該分
周器との出力を合成する合成器の２つの部分を含む４つ
の部分を設け、受信側では該合成器の出力を該分周器の
出力と該変調器の出力に分離する分離部と、該分離部か
ら又は直接に得られた該分周器の出力をＮ逓倍する逓倍
器と、該逓倍器の出力を受信側発振器の出力と混合して
音声帯域内に変換する周波数変換部と、又は該変調器の
出力を復調して得られた包絡線成分で該周波数変換部の
出力を振幅変調する復調・変調部を設け、送信側では該
送信側発振器の発振周波数、該分周器の分周比、 ＳＳ
Ｂ発生部における上側ＳＳＢ波又は下側ＳＳＢ波の選択
のうち少なくとも１つをランダムに切替え、受信側では
該送信側の切替えに対応して該受信側発振器の発振周波
数、逓倍器の逓倍数、上側ＳＳＢ波又は下側ＳＳＢ波の
選択を切替える本発明の秘話方式により解決する。The above problem is caused by the SSB generation section that mixes the input audio signal with the output of the transmission side oscillator and converts it into a single sideband wave (hereinafter abbreviated as SSB wave) on the transmission side, and the SSB generation section. The output of the modulator is divided into two parts: a frequency divider that divides the output of the signal by N and converts it into the voice band, or a modulator that modulates a subcarrier with an envelope component extracted from the voice signal; Four parts are provided, including two parts of a combiner that combines the outputs of the frequency divider, and a separation part that separates the output of the combiner into the output of the frequency divider and the output of the modulator on the receiving side. , a multiplier that multiplies the output of the frequency divider obtained from the separation section or directly by N, and a frequency conversion section that mixes the output of the multiplier with the output of the receiving side oscillator and converts it into the audio band. , or a demodulation/modulation section that amplitude-modulates the output of the frequency conversion section using the envelope component obtained by demodulating the output of the modulator, and on the transmitting side, the oscillation frequency of the transmitting side oscillator, the frequency divider The division ratio of SS
At least one of the upper SSB wave and the lower SSB wave is randomly switched in the B generating section, and on the receiving side, in response to the switching on the transmitting side, the oscillation frequency of the receiving side oscillator, the multiplier of the multiplier, This problem is solved by the secret communication method of the present invention that switches the selection of the upper SSB wave or the lower SSB wave.
本発明は比較的簡単な回路構成で高い秘話性を保つ様に
する為、送信側では音声信号を音声帯域外のＳＳＢ波に
変換した後、Ｎ分周して再び音声帯域内の分周波に変換
すると共に、前記の音声信号の包絡線成分を取出し、こ
れで副搬送波を変調する。そして、上記の変調波と分周
波とからなる合成波で更に搬送波を例えば周波数変調し
て外部に送出する。In order to maintain high confidentiality with a relatively simple circuit configuration, the present invention converts the audio signal into an SSB wave outside the audio band on the transmitting side, then divides the frequency by N and converts it back into a frequency-divided wave within the audio band. At the same time, the envelope component of the audio signal is extracted and used to modulate the subcarrier. Then, the carrier wave is further frequency-modulated, for example, by a composite wave consisting of the modulated wave and the frequency-divided wave, and is sent to the outside.
受信側では、上記の周波数変調波を復調して合成波を取
出して変調波と分周波とに分離し、前者から包絡線成分
を抽出し、後者はＮ逓倍された後に再び音声帯域内の波
になる様に周波数変換される。そして、この波は抽出さ
れた包絡線成分で振幅変調されて包絡線成分を含む音声
信号が得られる。On the receiving side, the above-mentioned frequency modulated wave is demodulated, a synthesized wave is extracted, and the synthesized wave is separated into a modulated wave and a frequency-divided wave.The envelope component is extracted from the former, and the latter is multiplied by N and then converted into a wave within the voice band again. The frequency is converted so that This wave is then amplitude-modulated with the extracted envelope component to obtain an audio signal including the envelope component.
ここで、送信側発振器の発信周波数５分周器の分周比、
ＳＳＢ発生部よりの出力として上側５ＳＩｌ波又は下
側ＳＳＳ波の選択のうち少なくとも１つを例えば略ラン
ダムなパルスを出力する擬似ランダム符号（以下ＰＮ符
号と省略する）発生器よりの出力で切替える。Here, the frequency division ratio of the oscillation frequency 5 divider of the transmitting side oscillator,
At least one of the upper 5SIl waves and the lower SSS wave is selected as the output from the SSB generator, for example, by the output from a pseudorandom code (hereinafter abbreviated as PN code) generator that outputs substantially random pulses.
受信側では、送信側の切替えに対応して受信側発振器の
発振周波数、逓倍器の逓倍数、上側ＳＳＢ波又は下側Ｓ
ＳＢ波の選択を切替える。On the receiving side, in response to switching on the transmitting side, the oscillation frequency of the receiving side oscillator, the multiplication number of the multiplier, the upper SSB wave or the lower SSB wave
Switch the SB wave selection.
そこで、ＰＮ符号発生器を付加すると云う簡単な回路構
成にも拘わらず切替えが略ランダムに行われるので高い
秘話性を有する。Therefore, despite the simple circuit configuration of adding a PN code generator, the switching is performed almost randomly, so that high confidentiality is achieved.
尚、音声信号の包絡線成分の利用の存無と上記の秘話性
とは無関係で通話品質の問題である。Note that the presence or absence of the use of the envelope component of the voice signal has nothing to do with the above-mentioned confidentiality, and is a problem of speech quality.
以下図示実施例により、本発明の内容を具体的に説明す
る。尚、全図を通じて同一符号は同一対象物を示す。The contents of the present invention will be specifically explained below with reference to illustrated embodiments. Note that the same reference numerals indicate the same objects throughout the figures.
第１図は本発明の一実施例のブロック図で、第２図は第
１図の周波数スペクトラムを示す。尚、第２図中の例え
ば■は第１図中の■の点の周波数スペクトラムを示す。FIG. 1 is a block diagram of an embodiment of the present invention, and FIG. 2 shows the frequency spectrum of FIG. Note that, for example, ■ in FIG. 2 indicates the frequency spectrum of the point ■ in FIG.
第１図の送信側において、端子ＭＯＤ ＩＮに加えられ
た０、３〜３．４ ＫＨｚの成分を有する音声信号は、
ＳＳＢ発生部内の周波数変換器１−１で送信側発信器１
−２からの出力と混合された後、帯域通過型ろ波器１−
３を通過し、 ＳＳＢ波に変換される。このＳＳＢ波は
振幅制限器２を通過後１分周器３でＮ分周されて音声帯
域内の分周波に再び変換される。On the transmitting side of FIG. 1, an audio signal having a component of 0.3-3.4 KHz applied to the terminal MOD IN is
Transmitting side oscillator 1 at frequency converter 1-1 in the SSB generator
-2, and then mixed with the output from bandpass filter 1-
3 and is converted into an SSB wave. After passing through the amplitude limiter 2, this SSB wave is frequency-divided by N in a 1-frequency divider 3 and converted again into a frequency-divided wave within the voice band.
一方、音声信号の包絡線成分を検波器４で取出し、この
成分を用いて、変調器５で副搬送波を周波数変調する。On the other hand, a detector 4 extracts the envelope component of the audio signal, and a modulator 5 frequency-modulates the subcarrier using this component.
この変調波と前記の分周波とて構成された合成波が端子
ＭＯＤ ＯＵＴより送出される（第２図送信側参照）。A composite wave composed of this modulated wave and the frequency-divided wave described above is sent out from the terminal MOD OUT (see the transmitting side in FIG. 2).
受信側では、端子ＯＥＭ ＩＮに加えられた合成波は分
離部内の低域通過型ろ波器６と高域通過型ろ波器１１で
分周波と変調波に分離される。On the receiving side, the composite wave applied to the terminal OEM IN is separated into a frequency-divided wave and a modulated wave by a low-pass filter 6 and a high-pass filter 11 in the separating section.
分周波は逓倍器７でＮ逓倍された後１周波数変換器８で
受信側発振器９の出力と混合されて音声帯域の波に変換
される。この波は低域通過型ろ波器１０を通って振幅変
調器１３に加えられる。The frequency-divided wave is multiplied by N in a multiplier 7, and then mixed with the output of the receiving side oscillator 9 in a single frequency converter 8 and converted into a voice band wave. This wave passes through a low-pass filter 10 and is applied to an amplitude modulator 13.
一方、変調波は復調器１２で復調されて包絡線成分が取
出され、同じく振幅変調器１３に加えられるので、包絡
線成分を含んだ音声信号が端子ＯＥＭ ００Ｔより送出
される（第２図受信側参照）。On the other hand, the modulated wave is demodulated by the demodulator 12 to extract the envelope component, which is also applied to the amplitude modulator 13, so that an audio signal containing the envelope component is sent from the terminal OEM 00T (see Fig. 2). (see side).
ここで、送信側及び受信側発振器１−２及び９の発振周
波数の切替え２分周器３と逓倍器７の分周比と逓倍数の
切替え、ＳＳＢ波を得る為に上側のＳＳＢ波を取るか下
側のＳＳＢ波を取るかの選択について、少なくとも１つ
ランダムに切替える事により秘話性が高くなる。Here, switch the oscillation frequencies of the transmitter and receiver oscillators 1-2 and 9, switch the division ratio and multiplier of the frequency divider 3 and multiplier 7, and take the upper SSB wave to obtain the SSB wave. Confidentiality can be improved by randomly switching at least one selection of whether to take the lower SSB wave or the lower SSB wave.
そこで、この切替えを略ランダムなパルスを出力するＰ
Ｎ符号発生器２０で制御する様にした。Therefore, P
It is controlled by an N code generator 20.
勿論、送信側と受信側は同じＰＮ符号発生器を使用し、
互いに同期している事が必要であり、他の手段（例えば
別途クロックを伝送する等）で同期が取れればよい。Of course, the transmitter and receiver use the same PN code generator,
It is necessary that they be synchronized with each other, and synchronization can be achieved by other means (for example, by transmitting a separate clock).
第３図は本発明の別の一実施例のブロック図を示す。FIG. 3 shows a block diagram of another embodiment of the invention.
図に示す様に、第１図より音声信号の包絡線成分を取出
す部分を除去したもので、前述と同じ部分の切替えをＰ
Ｎ符号発生器１４の出力で制御する。As shown in the figure, the part that extracts the envelope component of the audio signal is removed from Figure 1, and the same part as above is switched by P.
It is controlled by the output of the N code generator 14.
尚、包絡線成分を利用しないので通話品質は第１図の場
合よりも低下するが、通話の内容は了解する事ができる
。Note that since the envelope component is not used, the quality of the call is lower than in the case of FIG. 1, but the content of the call can be understood.
第４図は第１図又は第３図のＳＳＢ発生部１の別のブロ
ック図を示す。FIG. 4 shows another block diagram of the SSB generator 1 of FIG. 1 or 3. In FIG.
図において、端子間Ｄ ＩＮよりの音声信号は分割され
、一部は９０度位相器１５を介して周波数変換器１６に
、残りの部分はそのまま周波数変換器１４に加えられる
。これらの周波数変換器には、９０度位相器１７により
位相が互いに９０度異なる発振器１８の出力が加えられ
ているので、混合・合成されて端子ＯＵＴよりＳＳＢ波
が得られる。In the figure, the audio signal from the terminal-to-terminal D IN is divided, and a part is applied to the frequency converter 16 via the 90-degree phase shifter 15, and the remaining part is applied to the frequency converter 14 as it is. Since the outputs of the oscillators 18 whose phases differ by 90 degrees from each other are applied to these frequency converters by the 90-degree phase shifter 17, they are mixed and synthesized to obtain an SSB wave from the terminal OUT.
ここで、ＰＮ符号発生器（図示せず）の出力でスイッチ
２２をランダムに駆動して１８０度の位相器１９を挿入
又は短絡する事により、下側又は上側ＳＳＢ波がランダ
ムに得られる。Here, by randomly driving the switch 22 with the output of a PN code generator (not shown) and inserting or short-circuiting the 180 degree phase shifter 19, a lower or upper SSB wave can be randomly obtained.
第５図は第１図又は第３図の逓倍器のブロック図を示す
。FIG. 5 shows a block diagram of the multiplier of FIG. 1 or 3. FIG.
図において、端子ＩＮに加えられた分周波と、電圧制御
発振器７−４の出力をＮ１分周回路７−３−１を通した
波との位相差を位相検波器７−１で検出し、その位相差
に相当する検出出力が低域通過型ろ波器７−２を介して
電圧制御発振器７−４に加えられ、検出出力がＯになる
様に発振器７−４の発振周波数が制御される。そこで、
端子ＯＵＴより端子ＩＮに加えられた分周波のＮ１倍の
周波数の波が出力される。In the figure, a phase detector 7-1 detects the phase difference between the frequency-divided wave applied to the terminal IN and the wave output from the voltage-controlled oscillator 7-4 through the N1 frequency divider circuit 7-3-1. A detection output corresponding to the phase difference is applied to the voltage controlled oscillator 7-4 via the low-pass filter 7-2, and the oscillation frequency of the oscillator 7-4 is controlled so that the detection output becomes O. Ru. Therefore,
A wave with a frequency N1 times the frequency-divided wave applied to the terminal IN is output from the terminal OUT.
尚、ＰＮ符号発生器の出力でスイッチ２３を駆動させて
逓倍数Ｎ１とＮ２とをランダムに切替える。Note that the switch 23 is driven by the output of the PN code generator to randomly switch between the multipliers N1 and N2.
以上詳細に説明した様に、本発明によれば比較的簡単な
回路構成で高い秘話性が得られると云う効果が得られる
。As described above in detail, according to the present invention, it is possible to obtain the effect of obtaining high confidentiality with a relatively simple circuit configuration.
第１図本発明の一実施例のブロック図、第２図は第１図
の周波数スペクトラム、第３図は本発明の別のブロック
図、
図において、
１はＳＳ８発生部、 ３は分周器、
４は検波器、 ５は変調器、
６．１０は低域通過型ろ波器、
７は逓倍器、 ８は周波数変換器、２０はＰＮ符号
発生器を示す。
送イ吉４貝１１
堂 俸 刺
合べ戒
＊ ２ 幻
５．５５楚生部
茅
を港便１
３ 犯Fig. 1 is a block diagram of an embodiment of the present invention, Fig. 2 is a frequency spectrum of Fig. 1, and Fig. 3 is another block diagram of the present invention. In the figures, 1 is an SS8 generator, and 3 is a frequency divider. , 4 is a detector, 5 is a modulator, 6.10 is a low-pass filter, 7 is a multiplier, 8 is a frequency converter, and 20 is a PN code generator. Senkichi 4 Shells 11 Hall Salary Sashiaibe Precept * 2 Vision 5.55 Chuobe Kaya wo Port Delivery 1 3 Crime
Claims (1)
力と混合して単側波帯波に変換する単側波帯発生部と、
該単側波帯発生部よりの出力をＮ分周して音声帯域内に
変換する分周器と、該音声信号から抽出された包絡線成
分で副搬送波を変調する変調器と、該変調器の出力と該
分周器との出力を合成する合成器を設け、受信側では該
合成器の出力を該分周器と該変調器の出力に分離する分
離部と、該分離部の出力のうち該分周器の出力をＮ逓倍
する逓倍器と、該逓倍器の出力を受信側発振器の出力と
混合して音声帯域内に変換する周波数変換部と、該変調
器の出力を復調して得られた包絡線成分で該周波数変換
部の出力を振幅変調する復調・変調部を設け、送信側で
は該送信側発振器の発振周波数、該分周器の分周比、該
単側波帯発生部における上側単側波帯波又は下側単側波
帯波の選択のうち少なくとも１つをランダムに切替え、
該受信側では該送信側の切替えに対応して該受信側発振
器の発振周波数、該逓倍器の逓倍数、上側単側波帯波又
は下側単側波帯波の選択を切替える様にした事を特徴と
する秘話方式。 ２、送信側では入力された音声信号を送信側発振器の出
力と混合して単側波帯波に変換する単側波帯発生部と、
該単側波帯発生部よりの出力をＮ分周して音声帯域内に
変換する分周器を設け、受信側では該分周器の出力をＮ
逓倍する逓倍器と、該逓倍器の出力を受信側発振器の出
力と混合して音声帯域内に変換する周波数変換部を設け
、送信側では該送信側発振器の発振周波数、該分周器の
分周比、該単側波帯発生部における上側単側波帯波又は
下側単側波帯波の選択のうち少なくとも１つをランダム
に切替え、該受信側では該送信側の切替えに対応して該
受信側発振器の発振周波数、該逓倍器の逓倍数、上側単
側波帯波又は下側単側波帯波の選択を切替える様にした
事を特徴とする秘話方式。[Claims] 1. On the transmitting side, a single sideband generator mixes the input audio signal with the output of the transmitting side oscillator and converts it into a single sideband wave;
a frequency divider that divides the output from the single sideband generator into N and converts it into an audio band; a modulator that modulates a subcarrier with an envelope component extracted from the audio signal; and the modulator. A combiner is provided to combine the output of the frequency divider and the output of the frequency divider, and on the receiving side, a separation unit that separates the output of the combiner into the output of the frequency divider and the output of the modulator, and a A multiplier that multiplies the output of the frequency divider by N, a frequency converter that mixes the output of the multiplier with the output of the receiving side oscillator and converts it within the audio band, and a frequency converter that demodulates the output of the modulator. A demodulation/modulation section is provided that amplitude modulates the output of the frequency conversion section using the obtained envelope component, and on the transmission side, the oscillation frequency of the transmission side oscillator, the division ratio of the frequency divider, and the single sideband generation are provided. randomly switching at least one of the upper single sideband wave and the lower single sideband wave in the section;
On the receiving side, in response to switching on the transmitting side, the oscillation frequency of the receiving side oscillator, the multiplication number of the multiplier, and the selection of an upper single sideband wave or a lower side single sideband wave are switched. A secret method characterized by. 2. On the transmitting side, a single sideband generator mixes the input audio signal with the output of the transmitting side oscillator and converts it into a single sideband wave;
A frequency divider is provided that divides the output from the single sideband generator into N and converts it into the voice band, and on the receiving side, the output of the frequency divider is divided into N.
A frequency converter that mixes the output of the multiplier with the output of the receiving oscillator and converts it within the audio band is provided. randomly switching at least one of frequency ratio, selection of an upper single sideband wave or a lower single sideband wave in the single sideband generating section, and on the receiving side in response to the switching on the transmitting side. A secret communication system characterized in that the oscillation frequency of the receiving side oscillator, the multiplication number of the multiplier, and selection of an upper single sideband wave or a lower single sideband wave are switched.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3796185A JPS61198839A (en) | 1985-02-27 | 1985-02-27 | Privacy call system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3796185A JPS61198839A (en) | 1985-02-27 | 1985-02-27 | Privacy call system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS61198839A true JPS61198839A (en) | 1986-09-03 |
Family
ID=12512153
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3796185A Pending JPS61198839A (en) | 1985-02-27 | 1985-02-27 | Privacy call system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61198839A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6430343A (en) * | 1987-07-27 | 1989-02-01 | Nec Corp | Secret call communicating equipment |
-
1985
- 1985-02-27 JP JP3796185A patent/JPS61198839A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6430343A (en) * | 1987-07-27 | 1989-02-01 | Nec Corp | Secret call communicating equipment |
| JPH0529176B2 (en) * | 1987-07-27 | 1993-04-28 | Nippon Electric Co |
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