Transmission device, reception device, and communication system and remote operating device each including transmission device and reception device

A communication system comprising a transmission device and a reception device, wherein:

• the transmission device includes:
• a first control unit that outputs transmission data;
• a signal transmission unit that receives the transmission data and converts the transmission data to a first frequency signal and a second frequency signal, the first frequency signal having a first frequency, the second frequency signal having a second frequency different from the first frequency;
• and
• a receiver that receives a third frequency signal generated based on the transmission data, converts the third frequency signal to a reply receipt signal, and outputs the reply receipt signal to the first control unit, the third frequency signal having a third frequency different from both of the first frequency and the second frequency,
• the signal transmission unit is configured to:
• first transmit a first signal having the first frequency;
• and
• transmit the first frequency signal after transmitting the first signal;
• transmit a second signal having the first frequency after transmitting the first frequency signal;
• and
• transmit the second frequency signal after transmitting the first frequency signal and before transmitting the second signal,
• a signal length of the first frequency signal is equal to a signal length of the first signal,
• in a case where the reply receipt signal is not detected in a first time after output of the transmission data to the signal transmission unit, the first control unit outputs the transmission data again to the signal transmission unit as first retransmission data, and
• in a case where the reply receipt signal is not detected in the first time, the first control unit outputs the first retransmission data to the signal transmission unit after a lapse of a first standby time since the first time has elapsed,
• the reception device includes:
• a signal reception unit that receives the first signal, the second signal, the first frequency signal and the second frequency signal, outputs a first reception signal based on the first frequency signal, and outputs a second reception signal based on the second frequency signal, and
• a second control unit that receives the first reception signal and the second reception signal,
• wherein the second control unit outputs a first control signal in a case where at least one of the first reception signal or the second reception signal includes the transmission data.

A remote operating device comprising an input unit, a transmission device, a reception device and a controlled unit, wherein:

• the transmission device includes:
• a first control unit that outputs transmission data based on an instruction signal input from the input unit;
• a signal transmission unit that receives the transmission data and converts the transmission data to a first frequency signal and a second frequency signal, the first frequency signal having a first frequency, the second frequency signal having a second frequency different from the first frequency;
• and
• a receiver that receives a third frequency signal generated based on the transmission data, converts the third frequency signal to a reply receipt signal, and outputs the reply receipt signal to the first control unit, the third frequency signal having a third frequency different from both of the first frequency and the second frequency,
• the signal transmission unit is configured to:
• first transmit a first signal having the first frequency;
• and
• transmit the first frequency signal after transmitting the first signal;
• transmit a second signal having the first frequency after transmitting the first frequency signal;
• and
• transmit the second frequency signal after transmitting the first frequency signal and before transmitting the second signal,
• a signal length of the first frequency signal is equal td a signal length of the first signal,
• in a case where the reply receipt signal is not detected in a first time after output of the transmission data to the signal transmission unit, the first control unit outputs the transmission data again to the signal transmission unit as first retransmission data, and
• in a case where the reply receipt signal is not detected in the first time, the first control unit outputs the first retransmission data to the signal transmission unit after a lapse of a first standby time since the first time has elapsed,
• the reception device includes:
• a signal reception unit that receives the first frequency signal, the second signal, and the second frequency signal, outputs a first reception signal based on the first frequency signal, and outputs a second reception signal based on the second frequency signal;
• and
• a second control unit that receives the first reception signal and the second reception signal,
• the second control unit outputs the first control signal to the controlled unit in a case where at least one of the first reception signal or the second reception signal includes the transmission data.