JP3067144B2 - Secure communication system and transceiver - Google Patents
Secure communication system and transceiverInfo
- Publication number
- JP3067144B2 JP3067144B2 JP2669490A JP2669490A JP3067144B2 JP 3067144 B2 JP3067144 B2 JP 3067144B2 JP 2669490 A JP2669490 A JP 2669490A JP 2669490 A JP2669490 A JP 2669490A JP 3067144 B2 JP3067144 B2 JP 3067144B2
- Authority
- JP
- Japan
- Prior art keywords
- encryption key
- modulation
- spread
- band
- narrow
- 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.)
- Expired - Lifetime
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Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明はスペクトラム拡散変調を使用した秘匿通信方
式および送受信機に関する。Description: TECHNICAL FIELD The present invention relates to a secret communication system using spread spectrum modulation and a transceiver.
従来、スペクトラム拡散変調を用いた秘匿通信技術と
しては、通信情報をそのまま拡散符号によってスペクト
ラム拡散を行って伝送したり、あるいは、通信情報を所
定の暗号キーで暗号化した後、暗号化された通信情報お
よび暗号化キー全てに対して拡散符号でスペクトラム拡
散を行って伝送している。Conventionally, as a confidential communication technology using spread spectrum modulation, communication information is directly spread-spectrum-transmitted by a spreading code, or transmitted, or communication information is encrypted with a predetermined encryption key, and then encrypted communication is performed. All the information and the encryption key are transmitted by performing spread spectrum with a spread code.
上述した従来の秘匿通信技術では、伝送する情報全て
に対して拡散符号でスペクトラム拡散を行っているが、
拡散符号が解読されて情報が傍受されるのを回避するた
めに処理利得を大きくするため、所要周波数帯域幅が拡
大して周波数の有効活用ができないという欠点がある。In the above-mentioned conventional confidential communication technology, spread spectrum is performed on all information to be transmitted using a spread code.
Since the processing gain is increased to prevent the information from being intercepted by decoding the spreading code, there is a disadvantage that the required frequency bandwidth is expanded and the frequency cannot be effectively used.
本発明の目的は、伝送する情報の一部に対してのみス
ペクトラム拡散を用いることによって、所要周波数帯域
幅を拡大することなく秘匿通信を行うことができ、周波
数の有効活用ができる秘匿通信方式および送受信機を提
供することにある。An object of the present invention is to use a spread spectrum only for a part of information to be transmitted, to perform a confidential communication without expanding a required frequency bandwidth, and to use a confidential communication method capable of effectively utilizing a frequency. To provide a transceiver.
本発明の秘匿通信方式は、暗号化するための暗号キー
を生成する暗号キー生成手段と、前記暗号キーに基づい
て情報を暗号化する暗号化手段と、拡散符号を用いて搬
送波をスペクトラム拡散変調して変調搬送波を出力する
拡散変調手段と、前記スペクトラム拡散変調による所要
帯域幅よりは狭帯域の変調を行って変調搬送波を出力す
る第１および第２の狭帯域変調手段と、２つの変調搬送
波を合成する合成手段とを備え、情報を前記暗号化手段
によって暗号化したのち前記第１の狭帯域変調手段を介
して前記合成手段へ送出すると共に、前記暗号キーを前
記第２の狭帯域変調手段および前記拡散変調手段を介し
て前記合成手段へ送出する送信機と；前記第１および第
２の狭帯域変調手段によって変調された変調搬送波をそ
れぞれ復調する第１および第２の狭帯域復調手段と、前
記拡散変調手段によってスペクトラム拡散変調された変
調搬送波を復調する拡散復調手段と、暗号キーに基づい
て情報を解読する暗号解読手段とを備え、前記第１の狭
帯域復調手段によって暗号化された情報を再生し、ま
た、前記スペクトラム拡散復調手段および前記第２の狭
帯域復調手段によって前記暗号キーを再生し前記暗号解
読手段によって前記暗号化された情報を解読する受信機
とから構成される。The secret communication system according to the present invention includes an encryption key generation unit that generates an encryption key for encryption, an encryption unit that encrypts information based on the encryption key, and a spread spectrum modulation method that modulates a carrier using a spread code. Spread modulating means for outputting a modulated carrier, first and second narrow band modulating means for performing modulation in a band narrower than a required bandwidth by the spread spectrum modulation and outputting a modulated carrier, and two modulated carriers. Combining means for encrypting information, transmitting the encrypted information to the combining means via the first narrowband modulation means, and transmitting the encryption key to the second narrowband modulation means. Means for transmitting to the combining means via the means and the spread modulation means; and a first means for demodulating the modulated carriers modulated by the first and second narrow band modulation means, respectively. And a second narrow-band demodulator, a spread demodulator for demodulating a modulated carrier that has been spread-spectrum-modulated by the spread modulator, and a decryptor for decrypting information based on a cryptographic key. Reproducing information encrypted by the narrow-band demodulation means, reproducing the encryption key by the spread spectrum demodulation means and the second narrow-band demodulation means, and decrypting the encrypted information by the decryption means Receiver.
本発明の送信機は、暗号化するための暗号キーを生成
する暗号キー生成手段と、前記暗号キーに基づいて情報
を暗号化する暗号化手段と、拡散符号を用いて搬送波を
スペクトラム拡散変調して変調搬送波を出力する拡散変
調手段と、前記スペクトラム拡散変調による所要帯域幅
よりは狭帯域の変調を行って変調搬送波を出力する第１
および第２の狭帯域変調手段と、２つの変調搬送波を合
成する合成手段とを備え、情報を前記暗号化手段によっ
て暗号化したのち前記第１の狭帯域変調手段を介して前
記合成手段へ送出すると共に、前記暗号キーを前記第２
の狭帯域変調手段および前記拡散変調手段を介して前記
合成手段へ送出する構成である。The transmitter according to the present invention includes an encryption key generation unit that generates an encryption key for encryption, an encryption unit that encrypts information based on the encryption key, and a spread spectrum modulation of a carrier using a spreading code. A spread modulation means for outputting a modulated carrier wave, and a first modulating means for performing modulation in a band narrower than a required bandwidth by the spread spectrum modulation and outputting a modulated carrier wave.
And second synthesizing means for synthesizing the two modulated carriers, and information is encrypted by the encryption means and then transmitted to the synthesizing means via the first narrow band modulation means. And encrypting the encryption key with the second
And transmitting it to the synthesizing means via the narrow band modulation means and the spread modulation means.
情報を暗号化したのちスペクトラム拡散変調して送出
された受信信号をそれぞれ復調する第１および第２の狭
帯域復調手段と、前記拡散変調手段によってスペクトラ
ム拡散変調された変調搬送波を復調する拡散復調手段
と、暗号キーに基づいて情報を解読する暗号解読手段と
を備え、前記第１の狭帯域復調手段によって暗号化され
た情報を再生し、また、前記スペクトラム拡散復調手段
および前記第２の狭帯域復調手段によって前記暗号キー
を再生し前記暗号解読手段によって前記暗号化された情
報を解読する構成である。First and second narrow-band demodulating means for respectively demodulating a received signal transmitted after spread-spectrum modulation after encrypting information, and spread demodulating means for demodulating a modulated carrier wave spread-spectrum modulated by the spread modulation means And decryption means for decrypting information based on the encryption key, reproducing the information encrypted by the first narrowband demodulation means, and further comprising the spread spectrum demodulation means and the second narrowband demodulation means. The decryption means reproduces the encryption key, and the decryption means decrypts the encrypted information.
次に図面を参照して本発明を説明する。 Next, the present invention will be described with reference to the drawings.
第１図は本発明の一実施例を示すブロック図である。
送信機10は、暗号キー生成部11、暗号化部12、狭帯域変
調部13,14、スペクトラム拡散変調部15、合成部16、送
信部17を備えている。また、受信機20は、受信部21、ス
ペクトラム拡散復調部22、狭帯域復調部23,24、暗号解
読部25を備えている。FIG. 1 is a block diagram showing one embodiment of the present invention.
The transmitter 10 includes an encryption key generation unit 11, an encryption unit 12, narrowband modulation units 13 and 14, a spread spectrum modulation unit 15, a synthesis unit 16, and a transmission unit 17. Further, the receiver 20 includes a receiving unit 21, a spread spectrum demodulation unit 22, narrow band demodulation units 23 and 24, and a decryption unit 25.
送信機10の暗号キー生成物11は、情報信号C0を暗号化
するための暗号キー信号K0を生成し出力する。暗号化部
12は、暗号キー生成部11から暗号キー信号K0を受けて情
報信号C0を暗号化して暗号化情報信号C1を出力する。狭
帯域変調部13は、暗号化情報信号C1により搬送波に対し
狭帯域な変調を行って情報変調搬送信号C2として出力す
る。なお、ここでいう狭帯域変調とは、スペクトラム拡
散変調の所要帯域幅よりは狭帯域の所要帯域幅となる変
調という意味である。同様に、狭帯域変調部14は、暗号
キー信号K0により搬送波に対し狭帯域な変調を行って変
調搬送信号K1として出力する。スペクトラム拡散変調部
15は、変調搬送信号K1に対し拡散符号を用いてスペクト
ラム拡散変調を行い暗号キー変調搬送信号K2として出力
する。合成部16は、情報変調搬送信号C2および暗号キー
変調搬送信号K2を合成して合成信号C2＋K2を送信部17へ
送出する。送信部17は、合成信号C2＋K2を所定の送信周
波数に周波数変換および電力増幅を行って送信する。Encryption key product 11 of the transmitter 10, the information signal C 0 and generates and outputs the encryption key signal K 0 for encrypting. Encryption section
12 outputs the encrypted information signal C 1 encrypts information signal C 0 from the encryption key generator 11 receives the encryption key signal K 0. Narrow band modulation section 13 performs narrow band modulation on the carrier using the encrypted information signal C 1 and outputs the result as an information modulated carrier signal C 2 . Here, the narrow band modulation means a modulation in which the required bandwidth is narrower than the required bandwidth of the spread spectrum modulation. Similarly, the narrow-band modulation section 14 outputs a modulated carrier signal K 1 by performing narrowband modulation to a carrier wave by the encryption key signal K 0. Spread spectrum modulator
15 outputs the encryption key modulated carrier signal K 2 performs spread spectrum modulation using a spreading code to modulated carrier signal K 1. Combining unit 16 combines the information modulated carrier signal C 2 and encryption key modulated carrier signal K 2 sends a composite signal C 2 + K 2 to the transmission unit 17. The transmitting unit 17 performs frequency conversion and power amplification on the combined signal C 2 + K 2 to a predetermined transmission frequency, and transmits the signal.
第２図は情報変調搬送信号C2および暗号キー変調搬送
信号K2の周波数スペクトラムの一例を示す図であり、情
報変調搬送信号C2の周波数帯域幅Bcは、スペクトラム拡
散変調された暗号キー変調搬送信号K2の周波数帯域幅Bk
よりも狭帯域となっている。いま、情報信号C0の周期Ｔ
当りの情報シンボル数をDcとし、狭帯域変調による係数
をAc1とすれば、情報変調搬送信号C2の周波数帯域幅Bc
＝Ac1×Dc/Tとなる。また、暗号キー信号K0の周期Ｔ当
りの情報シンボル数をDkとし、狭帯域変調による係数を
Ak2、スペクトラム拡散変調による拡散係数をAk3とすれ
ば、暗号キー変調搬送信号K2の周波数帯域幅Bk＝Ak2×A
k3×Dk/Tとなる。情報信号C0の周期Ｔ当りの情報シンボ
ル数Dcと暗号キー信号K0の周期Ｔ当りの情報シンボル数
Dkを比較すれば、一般にDk≪Dcであるから、Dc＋Dkの情
報全てに対してスペクトラム拡散変調を行った場合より
もはるかに狭い周波数帯域幅とすることができる。FIG. 2 is a diagram showing an example of the frequency spectrum of the information modulated carrier signal C 2 and the encryption key modulated carrier signal K 2 , wherein the frequency bandwidth Bc of the information modulated carrier signal C 2 is the spread spectrum modulated encryption key modulation. carrier signal K 2 frequency bandwidth Bk
The band is narrower than that. Now, the period T of the information signal C 0
The number of information symbols per a Dc, narrow if the coefficient due to band modulation Ac 1 and the frequency bandwidth of the information modulated carrier signal C 2 Bc
= Ac 1 × Dc / T. Further, the number of information symbols per period T of the encryption key signal K 0 and Dk, the coefficient due to narrowband modulation
Ak 2, if the diffusion coefficient by the spread spectrum modulation and Ak 3, the frequency bandwidth of the encryption key modulated carrier signal K 2 Bk = Ak 2 × A
k 3 × Dk / T. The number of information symbols per period T of the information signal C information symbol number Dc and the encryption key signal K 0 per period T 0
When Dk is compared, Dk≪Dc is generally satisfied, so that the frequency bandwidth can be made much narrower than when spread spectrum modulation is performed on all information of Dc + Dk.
受信機20の受信部21は、送信機10から送信された電波
を受信して合成信号C2＋K2をスペクトラム拡散復調部22
および狭帯域復調部23へ出力する。スペクトラム拡散復
調部22は、入力する合成信号C2＋K2に対して送信側拡散
符号系列に等しいパターンの拡散符号系列との相関を求
めることにより復調する。この場合、合成信号C2＋K2の
内、スペクトラム拡散変調された暗号キー変調搬送信号
K2成分のみが復調されて変調搬送信号K1が再生され、狭
帯域変調された情報変調搬送信号C2成分は消滅する。ま
た、変調搬送信号K1は狭帯域復調部24で更に復調されて
暗号キー信号K0が再生される。The receiver 21 of the receiver 20 receives the radio wave transmitted from the transmitter 10 and converts the combined signal C 2 + K 2 into a spread spectrum demodulator 22.
And output to the narrowband demodulation unit 23. The spread spectrum demodulation unit 22 demodulates the input combined signal C 2 + K 2 by obtaining a correlation with a spread code sequence having a pattern equal to the transmission-side spread code sequence. In this case, of the composite signal C 2 + K 2 , the spread spectrum modulated encryption key modulated carrier signal
K only two components are reproduced modulated carrier signal K 1 is demodulated narrowband modulated information modulated carrier signal C 2 component disappears. The encryption key signal K 0 is reproduced modulated carrier signal K 1 is further demodulated by the narrowband demodulator 24.
一方、狭帯域復調部23は、入力する合成信号C2＋K2に
対して狭帯域復調を行う。この場合、合成信号C2＋K2の
内、狭帯域変調された電力密度の高い情報変調搬送信号
C2成分のみが復調されて暗号化された情報信号C1が再生
され、スペクトラム拡散変調された電力密度の低い暗号
キー変調搬送信号K2成分は消滅する。暗号解読部25は、
狭帯域復調部24で再生された暗号キー信号K0および狭帯
域復調部23で再生された暗号化された情報信号C1を受
け、暗号キー信号K0を基にこれを解読して情報信号C0を
出力する。On the other hand, the narrow-band demodulator 23 performs narrow-band demodulation on the input composite signal C 2 + K 2 . In this case, of the composite signal C 2 + K 2 , a narrow-band modulated information modulated carrier signal with a high power density
C Only 2 component is reproduced information signal C 1 that is encrypted is demodulated, low encryption key modulated carrier signal K 2 components of the spread spectrum modulated power density disappears. The decryption unit 25
Receives the information signal C 1 that is encrypted reproduced by narrow encryption key reproduced by the band demodulator 24 signals K 0 and narrowband demodulator 23, the information signal by decoding it based on the encryption key signal K 0 and it outputs the C 0.
以上説明したように本発明によれば、情報を暗号キー
に基づいて暗号化し、暗号キーに対してのみスペクトラ
ム拡散変調を行うので、所要周波数帯域幅を充分に狭く
することができて周波数の有効活用を図ることができ、
また、暗号化された全ての情報に対してスペクトラム拡
散変調を行ったのと同程度の秘匿性、すなわち耐傍受性
を持たせることができる。As described above, according to the present invention, the information is encrypted based on the encryption key and the spread spectrum modulation is performed only on the encryption key. Therefore, the required frequency bandwidth can be sufficiently narrowed, and the frequency can be effectively used. Can be used,
In addition, the same level of confidentiality as when spread spectrum modulation is performed on all the encrypted information, that is, resistance to interception can be provided.
第１図は本発明の一実施例を示すブロック図、第２図は
情報変調搬送信号C2および暗号キー変調搬送信号K2の周
波数スペクトラムの一例を示す図である。 10……送信機、11……暗号キー生成部、12……暗号化
部、13,14……狭帯域変調部、15……スペクトラム拡散
変調部、16……合成部、17……送信部、20……受信機、
21……受信部、22……スペクトラム拡散復調部、23,24
……狭帯域復調部、25……暗号解読部、C0……情報信
号、K0……暗号キー信号、C2……情報変調搬送信号、K2
……暗号キー変調搬送信号。Block diagram showing an embodiment of FIG. 1 according to the present invention, FIG. 2 is a diagram showing an example of a frequency spectrum of the information modulated carrier signals C 2 and encryption key modulated carrier signal K 2. 10 transmitter, 11 encryption key generation unit, 12 encryption unit, 13, 14 narrow band modulation unit, 15 spread spectrum modulation unit, 16 synthesis unit, 17 transmission unit , 20 …… Receiver,
21 ... Receiver, 22 ... Spread spectrum demodulator, 23,24
…… Narrow band demodulator, 25… Decryptor, C 0 …… Information signal, K 0 …… Encryption key signal, C 2 …… Information modulated carrier signal, K 2
…… Cryptographic key modulated carrier signal.
Claims (3)
キー生成手段と、前記暗号キーに基づいて情報を暗号化
する暗号化手段と、拡散符号を用いて搬送波をスペクト
ラム拡散変調して変調搬送波を出力する拡散変調手段
と、前記スペクトラム拡散変調による所要帯域幅よりは
狭帯域の変調を行って変調搬送波を出力する第１および
第２の狭帯域変調手段と、２つの変調搬送波を合成する
合成手段とを備え、情報を前記暗号化手段によって暗号
化したのち前記第１の狭帯域変調手段を介して前記合成
手段へ送出すると共に、前記暗号キーを前記第２の狭帯
域変調手段および前記拡散変調手段を介して前記合成手
段へ送出する送信機と；前記第１および第２の狭帯域変
調手段によって変調された変調搬送波をそれぞれ復調す
る第１および第２の狭帯域復調手段と、前記拡散変調手
段によってスペクトラム拡散変調された変調搬送波を復
調する拡散復調手段と、暗号キーに基づいて情報を解読
する暗号解読手段とを備え、前記第１の狭帯域復調手段
によって暗号化された情報を再生し、また、前記スペク
トラム拡散復調手段および前記第２の狭帯域復調手段に
よって前記暗号キーを再生し前記暗号解読手段によって
前記暗号化された情報を解読する受信機とから構成され
ることを特徴とする秘匿通信方式。1. An encryption key generation means for generating an encryption key for encryption, an encryption means for encrypting information based on the encryption key, and a spread spectrum modulation of a carrier wave using a spreading code. Spread modulation means for outputting a carrier, first and second narrow band modulation means for performing modulation in a band narrower than the required bandwidth by the spread spectrum modulation and outputting a modulated carrier, and combining the two modulated carriers. Synthesizing means, the information is encrypted by the encrypting means and then sent to the synthesizing means via the first narrow-band modulating means, and the encryption key is transmitted to the second narrow-band modulating means and the A transmitter for transmitting to the synthesizing means via the spread modulating means; and first and second demodulating the modulated carriers modulated by the first and second narrow band modulating means, respectively. Band demodulation means, spread demodulation means for demodulating a modulated carrier wave spread by the spread modulation means, and decryption means for decrypting information based on an encryption key, wherein the first narrowband demodulation means A receiver that reproduces the encrypted information, and that reproduces the encryption key by the spread spectrum demodulation means and the second narrow band demodulation means and decrypts the encrypted information by the decryption means. A secret communication method characterized by being configured.
キー生成手段と、前記暗号キーに基づいて情報を暗号化
する暗号化手段と、拡散符号を用いて搬送波をスペクト
ラム拡散変調して変調搬送波を出力する拡散変調手段
と、前記スペクトラム拡散変調による所要帯域幅よりは
狭帯域の変調を行って変調搬送波を出力する第１および
第２の狭帯域変調手段と、２つの変調搬送波を合成する
合成手段とを備え、情報を前記暗号化手段によって暗号
化したのち前記第１の狭帯域変調手段を介して前記合成
手段へ送出すると共に、前記暗号キーを前記第２の狭帯
域変調手段および前記拡散変調手段を介して前記合成手
段へ送出することを特徴とする送信機。2. An encryption key generation means for generating an encryption key for encryption, an encryption means for encrypting information based on the encryption key, and a spread spectrum modulation of a carrier wave using a spreading code. Spread modulation means for outputting a carrier, first and second narrow band modulation means for performing modulation in a band narrower than the required bandwidth by the spread spectrum modulation and outputting a modulated carrier, and combining the two modulated carriers. Synthesizing means, the information is encrypted by the encrypting means and then transmitted to the synthesizing means via the first narrow-band modulating means, and the encryption key is transmitted to the second narrow-band modulating means and the A transmitter for transmitting the signal to the synthesizing unit via a spread modulation unit.
調して送出された受信信号をそれぞれ復調する第１およ
び第２の狭帯域復調手段と、前記拡散変調手段によって
スペクトラム拡散変調された変調搬送波を復調する拡散
復調手段と、暗号キーに基づいて情報を解読する暗号解
読手段とを備え、前記第１の狭帯域復調手段によって暗
号化された情報を再生し、また、前記スペクトラム拡散
復調手段および前記第２の狭帯域復調手段によって前記
暗号キーを再生し前記暗号解読手段によって前記暗号化
された情報を解読することを特徴とする受信機。3. A first and a second narrow band demodulating means for respectively demodulating a received signal transmitted after spread-spectrum modulation after encrypting information, and a modulated carrier wave spread-spectrum modulated by the spread modulation means. A demodulating means for demodulating, and a decryption means for decrypting information based on an encryption key, reproducing information encrypted by the first narrow-band demodulating means; A receiver characterized in that the encryption key is reproduced by a second narrow-band demodulation means and the encrypted information is decrypted by the decryption means.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2669490A JP3067144B2 (en) | 1990-02-05 | 1990-02-05 | Secure communication system and transceiver |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2669490A JP3067144B2 (en) | 1990-02-05 | 1990-02-05 | Secure communication system and transceiver |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH03230637A JPH03230637A (en) | 1991-10-14 |
| JP3067144B2 true JP3067144B2 (en) | 2000-07-17 |
Family
ID=12200498
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2669490A Expired - Lifetime JP3067144B2 (en) | 1990-02-05 | 1990-02-05 | Secure communication system and transceiver |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3067144B2 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2705639B2 (en) * | 1995-04-28 | 1998-01-28 | 日本電気株式会社 | CDMA device |
| WO2009104234A1 (en) * | 2008-02-18 | 2009-08-27 | 学校法人同志社 | Wireless device, wireless system, and method for confidential communication |
| DE102018110252A1 (en) * | 2018-04-27 | 2019-10-31 | Infineon Technologies Ag | Transceiver, system with transceivers and signal |
-
1990
- 1990-02-05 JP JP2669490A patent/JP3067144B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH03230637A (en) | 1991-10-14 |
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