摘要:
A data communication apparatus improves security against eavesdropping for secret communication by using Y-00 protocol. A multi-level code generation section generates, based on key information, a multi-level code sequence in which a signal level changes so as to be approximately random numbers. A level conversion section irreversibly converts the multi-level code sequence such that a converted multi-level code sequence does not constitute a mapping of the multi-level code sequence. A multi-level processing section generates a multi-level signal having a plurality of levels each corresponding to a combination between the information data and the multi-level code sequence. A modulator section modulates a multi-level signal in a predetermined modulation method and outputs a modulated signal.
摘要:
A data transmitting apparatus which improves security against eavesdropping is provided for secret communication using Y-00 protocol. The multi-level code generation section 111 generates, based on key information 11, a multi-level code sequence 12 in which a signal level changes so as to be approximately random numbers. The multi-level processing section 112 generates a multi-level signal 13 having a level which corresponds to a combination between information data 10 and the multi-level code sequence 12. The error signal generation section 113 generates an error signal 21 which changes randomly. The accumulation section 114 accumulates the error signal 21, and outputs an accumulated error signal 22. The adding section 116 adds the accumulated error signal 22 to the multi-level signal 13, and outputs a variable multi-level signal 23. The modulator section 117 modulates the variable multi-level signal 23, and outputs a modulated signal 14.
摘要:
A data transmitting apparatus has improved security against eavesdropping for secret communication using Y-00 protocol. The multi-level code generation section generates, based on key information, a multi-level code sequence in which a signal level changes so as to be approximately random numbers. The multi-level processing section generates a multi-level signal having a level which corresponds to a combination between information data and the multi-level code sequence. The error signal generation section generates an error signal which changes randomly. The accumulation section accumulates the error signal, and outputs an accumulated error signal. The adding section adds the accumulated error signal to the multi-level signal, and outputs a variable multi-level signal. The modulator section modulates the variable multi-level signal, and outputs a modulated signal.
摘要:
A data communication apparatus which improves security against eavesdropping is provided for secret communication using Y-00 protocol. In a data transmitting apparatus 101, a multi-level code generation section 111 generates, based on key information 11, a multi-level code sequence 12 in which a signal level changes so as to be approximately random numbers. A multi-level processing section 112 generates a multi-level signal 13 having a plurality of levels each corresponding to a combination between information data 10 and the multi-level code sequence 12. A level conversion section 113 divides the plurality of levels of the multi-level signal 13 into several groups, and allocates one level of a converted multi-level signal 21 to a plurality of levels included in each of the several groups in an overlapped manner. The level conversion section 113 then converts the multi-level signal 13 into the converted multi-level signal 21. A modulator section 114 modulates the converted multi-level signal 21 and outputs a modulated signal 14.
摘要:
A data communication apparatus which improves security against eavesdropping is provided for secret communication using Y-00 protocol. In a data transmitting apparatus 101, a multi-level code generation section 111 generates, based on key information 11, a multi-level code sequence 12 in which a signal level changes so as to be approximately random numbers. A multi-level processing section 112 generates a multi-level signal 13 having a plurality of levels each corresponding to a combination between information data 10 and the multi-level code sequence 12. A level conversion section 113 divides the plurality of levels of the multi-level signal 13 into several groups, and allocates one level of a converted multi-level signal 21 to a plurality of levels included in each of the several groups in an overlapped manner. The level conversion section 113 then converts the multi-level signal 13 into the converted multi-level signal 21. A modulator section 114 modulates the converted multi-level signal 21 and outputs a modulated signal 14.
摘要:
A data communication apparatus which improves security against eavesdropping is provided for secret communication using Y-00 protocol. A multi-level code generation section 111 generates, based on key information 11, a multi-level code sequence 12 in which signal in which a signal level changes so as to be approximately random numbers. A multi-level processing section 112 combines information data 10 and the multi-level code sequence 12, and generates a multi-level signal 13 having a plurality of levels each corresponding to the combination of the information data 10 and the multi-level code sequence 12. A delayed wave generation section 113 generates, based on a delay profile 19, a delayed wave of the multi-level signal 13, combines the generated delayed wave and the multi-level signal 13, and outputs a multipath signal 20. A modulator section 114 modulates the multipath signal 20 in a predetermined modulation method, and outputs a modulated signal 14.
摘要:
A data communication apparatus which improves security against eavesdropping is provided for secret communication using Y-00 protocol. A multi-level code generation section 111 generates, based on key information 11, a multi-level code sequence 12 in which a signal level changes so as to be approximately random numbers. A level conversion section 113 irreversibly converts the multi-level code sequence 12 such that a converted multi-level code sequence 19 does not constitute a mapping of the multi-level code sequence 12. A multi-level processing section 112 generates a multi-level signal 13 having a plurality of levels each corresponding to a combination between the information data 10 and the multi-level code sequence 12. A modulator section 114 modulates a multi-level signal 14 in a predetermined modulation method and outputs a modulated signal 15.
摘要:
A data communication apparatus which causes the eavesdropper to take a significantly increased time to analyze a cipher text and provides high concealability is provided. A multi-level code generation section 111a generates, based on predetermined key information 11, a multi-level code sequence 12 in which a signal level changes so as to be approximately random numbers. A multi-level processing section 111b combines the multi-level code sequence 12 and information data 10, and generates a multi-level signal 13 having a plurality of levels corresponding to the combination of the multi-level code sequence 12 and the information data 10. A modulator section 112 treats the multi-level signal a predetermined modulating processing and generates a modulated signal. The multi-level code generation section 111a generates the multi-level code sequence 12 in accordance with a changed random number sequence which results from changing a bit series of a binary random number sequence generated based on the predetermined key information.
摘要:
Provided is a data communication apparatus which is highly concealable and significantly increases time necessary for an eavesdropper to analyze cipher text. A multi-level code generation section (156a) generates, by using predetermined key information, a multi-level code sequence in which a signal level changes so as to be random numbers. The multi-level processing section (111b) combines a multi-level code sequence and information data, and generates a multi-level signal having a level corresponding to a combination of the multi-level code sequence and the information data. In the multi-level code generation section (156a), a random number sequence generation section (157) generates a binary random number sequence by using the predetermined key information. A multi-level conversion section (158) generates a multi-level code sequence from the binary random number sequence in accordance with a predetermined encoding rule.
摘要:
A data communication apparatus, performing a secret communication, is provided to reduce a random number generation speed using a plurality of random number generators. The data communication apparatus includes random number generation sections generating random numbers, which are each a multi-level pseudo random number, using predetermined key information includes a multi-level signal modulation section selecting a level, from among multi-levels previously prepared, selected level corresponding to information data and a multi-level sequence, which is composed of a combination of values of the random numbers and generating a multi-level modulated signal including a noise having a predetermined noise level using the selected level. Levels of a multi-level signal are in a range of the noise level, and a signal point allocation is set such that all values which are possibly taken by each of the random numbers are allocated to the plurality of levels of the multi-level signal.