State detection system, detection device, state detection method and state detection program

A detection device comprising:

• a receiver to receive signals of a same sequence repeatedly transmitted at a predetermined period by a transmission device via a propagation path of the signals transmitted by the transmission device;
• block division circuitry configured to divide the signals received by the receiver into blocks in units of the period;
• time correlation calculation circuitry configured to calculate a time correlation between the signals divided into blocks by the block division circuitry in units of the period;
• and
• determination circuitry configured to determine that an object on the propagation path is in a stationary state in a case where the time correlation calculated by the time correlation calculation circuitry is equal to or greater than a predetermined threshold value.

A state detection method for detecting a state of an object on a propagation path of a signal transmitted by a transmission device that transmits a predetermined signal, the state detection method comprising:

• receiving, via the propagation path, signals of a same sequence repeatedly transmitted at a predetermined period by the transmission device;
• dividing the signals received in receiving into blocks in units of the period;
• calculating a time correlation between the signals divided into blocks in dividing in units of the period;
• and
• determining that the object is in a stationary state in a case where the time correlation calculated in calculating is equal to or greater than a predetermined threshold value.