Communication device, communication system

A communication device comprising:

• a first circuit board in which a first component for communication is implemented;
• and
• a second circuit board in which a second component for communication is implemented,
• wherein a communication is performed between the first component and the second component,
• the first component includes a first transmitting unit and a control unit,
• the second component includes a storage unit, a judging unit, and a second transmitting unit,
• the first transmitting unit transmits a plurality of detection signals having different frequency spectrums to the second component,
• the storage unit of the second component stores information of detection signals that are to be received,
• upon receiving the detection signals from the first component, the judging unit of the second component judges authenticity of the received detection signals by referring to the information stored in the storage unit,
• the second transmitting unit transmits a judgment result of the judging unit to the first component, and
• when the judgment result received from the second component indicates that the detection signals are not authentic, the control unit of the first component adds a restriction to the communication performed between the first component and the second component.

A communication device comprising:

• a first circuit board in which a first component for communication is implemented;
• and
• a second circuit board in which a second component for communication is implemented,
• wherein a communication is performed between the first component and the second component,
• the second component includes a transmitting unit,
• the first component includes a judging unit and a control unit,
• the transmitting unit of the second component transmits a plurality of detection signals having different frequency spectrums to the first component,
• upon receiving the detection signals, the judging unit of the first component judges
• authenticity of the received detection signals, and
• when the judging unit judges that the received detection signals are not authentic, the control unit adds a restriction to the communication performed between the first component and the second component.

A communication system comprising:

• a first device having a first circuit board in which a first component for communication is implemented;
• and
• a second device having a second circuit board in which a second component for communication is implemented,
• wherein a communication is performed between the first device and the second device,
• the first component includes a transmitting unit, a judging unit, and a control unit,
• the second component includes a returning unit,
• the transmitting unit of the first component transmits a plurality of detection signals having different frequency spectrums to the second component,
• upon receiving the detection signals, the returning unit of the second component returns, as return signals, respective signal waveforms of the received detection signals to the first component,
• the judging unit of the first component judges authenticity of the received return signals by referring to the transmitted detection signals, and
• when the judging unit judges that the received return signals are not authentic, the control unit adds a restriction to the communication performed between the first component and the second component.

A communication device comprising:

• a first circuit board in which a first component for communication is implemented;
• and
• a second circuit board in which a second component for communication is implemented,
• wherein a communication is performed between the first component and the second component,
• the first component includes a transmitting unit, a judging unit, and a control unit,
• the second component includes a returning unit,
• the transmitting unit of the first component transmits, to the second component, a plurality of detection signals that are each a detection signal obtained by modulating a carrier signal by bits constituting a bit sequence that is generated from a pseudo-random bit sequence,
• upon receiving the detection signals, the returning unit of the second component returns, as return signals, respective signal waveforms of the received detection signals to the first component,
• the judging unit of the first component judges authenticity of the received return signals by referring to the transmitted detection signals, and
• when the judging unit judges that the received return signals are not authentic, the control unit adds a restriction to the communication performed between the first component and the second component.

A communication device for performing a communication with another device, comprising:

• a transmitting unit configured to transmit a plurality of detection signals having different frequency spectrums to the other device;
• a judging unit configured to, upon receiving signal waveforms of the transmitted detection signals from the other device as return signals, judge authenticity of the received return signals;
• and
• a control unit configured to add a restriction to the communication performed with the other device when the judging unit judges that the received return signals are not authentic;
• wherein
• the plurality of detection signals include:
• a detection signal obtained by modulating a carrier signal by bits constituting a first bit sequence;
• and
• a detection signal obtained by modulating the carrier signal by bits constituting a bit sequence that is composed of sequences of 0s and 1s that are each m times as many as each 0 and each 1 constituting the first bit sequence, wherein m is a natural number greater than 1.

A communication device for performing a communication with another device, comprising:

• a returning unit configured to, upon receiving a plurality of detection signals having different frequency spectrums, return, as return signals, respective signal waveforms of the received detection signals;
• wherein
• the other device includes:
• a transmitting unit configured to transmit the plurality of detection signals having different frequency spectrums to the communication device;
• a judging unit configured to, upon receiving the signal waveforms of the transmitted detection signals from the communication device as the return signals, judge authenticity of the received return signals;
• and
• a control unit configured to add a restriction to the communication performed with the communication device when the judging unit judges that the received return signals are not authentic.