A channel measurement method, comprising: receiving, by an access network device, a sounding reference signal SRS from a terminal device; receiving, by the access network device from the terminal device, a power adjustment factor used by first antenna ports, wherein the first antenna ports are antenna ports used by the terminal device to send a data signal, and the power adjustment factor is determined based on an electromagnetic wave specific absorption rate SAR detected by the first antenna ports, wherein different SARs are detected for the first antenna ports, and different power adjustment factors are used by the first antenna ports; determining, by the access network device, a first uplink channel based on the SRS; and determining, by the access network device, a target channel based on the first uplink channel and the power adjustment factor used by the first antenna ports, wherein the target channel is a target uplink channel or a target downlink channel; wherein the receiving, by the access network device from the terminal device, a power adjustment factor used by first antenna ports comprises: receiving, by the access network device from the terminal device, a power adjustment factor used by a target antenna port in the first antenna ports, and a ratio of a power adjustment factor used by a third antenna port to the power adjustment factor used by the target antenna port, wherein the third antenna port is an antenna port other than the target antenna port in the first antenna ports; and the determining, by the access network device, a target channel based on the first uplink channel and the power adjustment factor used by the first antenna ports comprises: computing, by the access network device, the target channel based on the first uplink channel, the power adjustment factor used by the target antenna port, and the ratio. receiving, by an access network device, a sounding reference signal SRS from a terminal device; receiving, by the access network device from the terminal device, a power adjustment factor used by first antenna ports, wherein the first antenna ports are antenna ports used by the terminal device to send a data signal, and the power adjustment factor is determined based on an electromagnetic wave specific absorption rate SAR detected by the first antenna ports, wherein different SARs are detected for the first antenna ports, and different power adjustment factors are used by the first antenna ports; determining, by the access network device, a first uplink channel based on the SRS; and determining, by the access network device, a target channel based on the first uplink channel and the power adjustment factor used by the first antenna ports, wherein the target channel is a target uplink channel or a target downlink channel; wherein the receiving, by the access network device from the terminal device, a power adjustment factor used by first antenna ports comprises: receiving, by the access network device from the terminal device, a power adjustment factor used by a target antenna port in the first antenna ports, and a ratio of a power adjustment factor used by a third antenna port to the power adjustment factor used by the target antenna port, wherein the third antenna port is an antenna port other than the target antenna port in the first antenna ports; and the determining, by the access network device, a target channel based on the first uplink channel and the power adjustment factor used by the first antenna ports comprises: computing, by the access network device, the target channel based on the first uplink channel, the power adjustment factor used by the target antenna port, and the ratio. receiving, by the access network device from the terminal device, a power adjustment factor used by a target antenna port in the first antenna ports, and a ratio of a power adjustment factor used by a third antenna port to the power adjustment factor used by the target antenna port, wherein the third antenna port is an antenna port other than the target antenna port in the first antenna ports; and the determining, by the access network device, a target channel based on the first uplink channel and the power adjustment factor used by the first antenna ports comprises: computing, by the access network device, the target channel based on the first uplink channel, the power adjustment factor used by the target antenna port, and the ratio.