Communication system, communication apparatus, and communication method

A communication device, including one or more processors, configured to restart supply of power that has been stopped in a sleep state upon reception of a startup instruction signal,

• wherein the communication device includes a signal processing unit that includes transmission data in a start completion signal, when generating the start completion signal that is a response signal to the startup instruction signal;
• wherein the communication device further includes a power supply control unit configured to control power supply;
• wherein the startup instruction signal includes power supply interval information indicating an interval of power supply performed during the sleep state by the power supply control unit;
• wherein the communication device further includes a reception unit configured to receive a signal transmitted by an external communication device;
• wherein the signal processing unit includes a lower signal processing unit configured to determine whether or not the signal received by the reception unit is the startup instruction signal;
• wherein the power supply control unit is configured to supply power to the reception unit and the lower signal processing unit during the sleep state according to an interval indicated by the power supply interval information;
• and
• wherein the external communication device is configured to transmit the startup instruction signal according to the interval indicated by the power supply interval information.

A communication method, comprising:

• transmitting, by a first communication device, a startup instruction signal;
• restarting, by a second communication device, supply of power stopped in a sleep state when receiving the startup instruction signal from the first communication device, and including transmission data in the start completion signal, when generating a start completion signal that is a response signal to the startup instruction signal, wherein the startup instruction signal includes power supply interval information indicating an interval of power supply performed during the sleep state by the second communication device;
• controlling power supply by the second communication device;
• receiving, by the second communication device, a signal transmitted by the first communication device;
• determining, by the second communication device, whether or not the signal received by the second communication device is the startup instruction signal;
• supplying, by the second communication device, power to a reception unit and a lower signal processing unit during the sleep state according to an interval indicated by the power supply interval information.