An optical transceiver configured to be used in a dense wavelength division multiplexing (DWDM) system, in communication with a remote optical transceiver over a single optical fiber using a wavelength band, the optical transceiver comprising: an optical transmitter configured to receive a first electrical signal and to convert the first electrical signal into a first optical signal that is to be transmitted over the single optical fiber to the remote optical transceiver, the first optical signal having a first center wavelength within the wavelength band; an optical receiver configured to receive a second optical signal from the remote optical transceiver and to convert the second optical signal into a second electrical signal, the second optical signal having a second center wavelength within the wavelength band and carrying second wavelength information of the second optical signal inserted by the remote optical transceiver; a transmission unit configured to receive a first data signal, insert first wavelength information into the first data signal, and send the first data signal including the first wavelength information as the first electrical signal to the optical transmitter; and a processing unit operatively coupled to the optical transmitter and the optical receiver, characterized in that the processing unit is configured to: obtain the first wavelength information of the first optical signal and second wavelength information of the second optical signal; and compare the first wavelength information of the first optical signal and the second wavelength information of the second optical signal so as to control a wavelength separation interval between the first optical signal and the second optical signal within the wavelength band for reducing interferences between the first optical signal and the second optical signal. an optical transmitter configured to receive a first electrical signal and to convert the first electrical signal into a first optical signal that is to be transmitted over the single optical fiber to the remote optical transceiver, the first optical signal having a first center wavelength within the wavelength band; an optical receiver configured to receive a second optical signal from the remote optical transceiver and to convert the second optical signal into a second electrical signal, the second optical signal having a second center wavelength within the wavelength band and carrying second wavelength information of the second optical signal inserted by the remote optical transceiver; a transmission unit configured to receive a first data signal, insert first wavelength information into the first data signal, and send the first data signal including the first wavelength information as the first electrical signal to the optical transmitter; and a processing unit operatively coupled to the optical transmitter and the optical receiver, characterized in that the processing unit is configured to: obtain the first wavelength information of the first optical signal and second wavelength information of the second optical signal; and compare the first wavelength information of the first optical signal and the second wavelength information of the second optical signal so as to control a wavelength separation interval between the first optical signal and the second optical signal within the wavelength band for reducing interferences between the first optical signal and the second optical signal. obtain the first wavelength information of the first optical signal and second wavelength information of the second optical signal; and compare the first wavelength information of the first optical signal and the second wavelength information of the second optical signal so as to control a wavelength separation interval between the first optical signal and the second optical signal within the wavelength band for reducing interferences between the first optical signal and the second optical signal.