A method for acquiring channel responses of a self-interference channel in a full-duplex communication device, comprising: obtaining estimate values of a channel response of the self-interfering channel by performing channel estimation for the self-interference channel through transmitting a plurality of reference signals at a plurality of frequency points, wherein a time interval between adjacent reference signals is less than a coherence time of the self-interference channel, and a frequency-domain interval between adjacent reference signals is less than a coherence bandwidth of the self-interfering channel; determining a frequency interval with stable frequency domain response of the self-interference channel according to the estimate values of the channel response of the self-interference channel; selecting among the plurality of frequency points, from the frequency interval with stable frequency domain response of the self-interference channel, a random frequency point or a frequency point with a relatively significant channel response as a transmission frequency point for a reference signal; acquiring, based on the estimate values of the channel response of the self-interfering channel, an interrelation between channel responses at the transmission frequency point and at a non-transmission frequency point among the plurality of frequency points; transmitting the reference signal at the transmission frequency point without transmitting the reference signal at the non-transmission frequency point; calculating a channel response Ĥ r at the transmission frequency point according to a received signal Y r at the transmission frequency point; calculating a channel response H i at the non-transmission frequency point according to the channel response Ĥ r at the transmission frequency point and the interrelation between channel responses at the transmission frequency point and at the non-transmission frequency point; and estimating channel responses in all time domain and frequency domain by performing interpolation separately or simultaneously in frequency domain and time domain. obtaining estimate values of a channel response of the self-interfering channel by performing channel estimation for the self-interference channel through transmitting a plurality of reference signals at a plurality of frequency points, wherein a time interval between adjacent reference signals is less than a coherence time of the self-interference channel, and a frequency-domain interval between adjacent reference signals is less than a coherence bandwidth of the self-interfering channel; determining a frequency interval with stable frequency domain response of the self-interference channel according to the estimate values of the channel response of the self-interference channel; selecting among the plurality of frequency points, from the frequency interval with stable frequency domain response of the self-interference channel, a random frequency point or a frequency point with a relatively significant channel response as a transmission frequency point for a reference signal; acquiring, based on the estimate values of the channel response of the self-interfering channel, an interrelation between channel responses at the transmission frequency point and at a non-transmission frequency point among the plurality of frequency points; transmitting the reference signal at the transmission frequency point without transmitting the reference signal at the non-transmission frequency point; calculating a channel response Ĥ r at the transmission frequency point according to a received signal Y r at the transmission frequency point; calculating a channel response H i at the non-transmission frequency point according to the channel response Ĥ r at the transmission frequency point and the interrelation between channel responses at the transmission frequency point and at the non-transmission frequency point; and estimating channel responses in all time domain and frequency domain by performing interpolation separately or simultaneously in frequency domain and time domain.