Communication method, device, and system

A terminal device, comprising at least one processor and one or more memories coupled to the at least one processor and storing programming instructions for execution by the at least one processor to cause the terminal device to perform operations of:

• receiving configuration information from a network device;
• receiving downlink control information from the network device;
• determining a first resource based on the configuration information, wherein the first resource is a resource that cannot be used to transmit a downlink data channel and a demodulation reference signal of the downlink data channel;
• determining a second resource based on the downlink control information, wherein the second resource comprises a resource used to transmit the downlink data channel and the demodulation reference signal of the downlink data channel;
• determining a third resource based on the first resource and the second resource, wherein the third resource is a resource that is in the second resource and that is used to transmit the downlink data channel and the demodulation reference signal of the downlink data channel;
• and
• receiving, on the third resource, the downlink data channel and the demodulation reference signal of the downlink data channel from the network device.

A network device, comprising at least one processor and one or more memories coupled to the at least one processor and storing programming instructions for execution by the at least one processor to cause the network device to perform operations of:

• sending configuration information to a terminal device, wherein the configuration information is used to determine a first resource, and the first resource is a resource that cannot be used to transmit a downlink data channel and a demodulation reference signal of the downlink data channel;
• sending downlink control information to the terminal device, wherein the downlink control information is used to determine a second resource, and the second resource comprises a resource used to transmit the downlink data channel and the demodulation reference signal of the downlink data channel;
• determining a third resource based on the first resource and the second resource, wherein the third resource is a resource that is in the second resource and that is used to transmit the downlink data channel and the demodulation reference signal of the downlink data channel;
• and
• transmitting, on the third resource, the downlink data channel and the demodulation reference signal of the downlink data channel to the terminal device.