According to a tenth aspect, an embodiment of this application further provides a communication system. The communication system may include a core network device and a network device. The core network device is configured to perform the wake up signal sending method shown in any implementation of the second aspect.
The network device is configured to perform the wake up signal sending method shown in any implementation of the third aspect.
In a possible implementation, the system further includes a communication device, and the communication device is configured to perform the wake up signal sending method shown in any implementation of the first aspect.