A compressive sensing-based signal processing method, comprising: determining distribution of signal components of an input signal in a baseband spectrum after frequency mixing has been performed on the input signal according to spectral distribution of the input signal; dividing the baseband spectrum according to different signal aliasing patterns formed by the distribution of the signal components, to form multiple frequency bands, wherein each of the frequency bands corresponds to one signal aliasing pattern; determining a frequency band comprising a largest quantity of aliased signals among the frequency bands, and using lowest sampling frequency required by the frequency band comprising the largest quantity of aliased signals as the lowest sampling frequency of the input signal according to the signal aliasing patterns in the frequency bands, wherein f s_ min = Q × f p, f s_ min is lowest sampling frequency, Q is maximum quantity of aliased signals in the frequency band, f p is a subband bandwidth, and performing sampling on the input signal at sampling frequency greater than or equal to the lowest sampling frequency, to obtain a sampled signal; determining a submatrix A Si, corresponding to an observation matrix A for compressive sensing sampling, in each frequency band of the multiple frequency bands according to the signal aliasing pattern in each frequency band of the multiple frequency bands, wherein i =1,..., K; separately restoring a baseband spectrum of the i th ( i =1,..., K) frequency band according to a signal restoration algorithm formula Z S i f = A S i + y f, wherein A S i + is a Moore Penrose inverse, matrix of a submatrix A Si of the i th frequency band, Z Si ( f) is the restored baseband spectrum of the i th frequency band, y ( f) is a discrete Fourier transformation of the sampled signal, and K is a total quantity of the frequency bands that are formed on the baseband spectrum; and splicing the restored baseband spectrums of the frequency bands, to obtain the entire baseband spectrum of the input signal, and restoring the input signal according to the baseband spectrum obtained through splicing. determining distribution of signal components of an input signal in a baseband spectrum after frequency mixing has been performed on the input signal according to spectral distribution of the input signal; dividing the baseband spectrum according to different signal aliasing patterns formed by the distribution of the signal components, to form multiple frequency bands, wherein each of the frequency bands corresponds to one signal aliasing pattern; determining a frequency band comprising a largest quantity of aliased signals among the frequency bands, and using lowest sampling frequency required by the frequency band comprising the largest quantity of aliased signals as the lowest sampling frequency of the input signal according to the signal aliasing patterns in the frequency bands, wherein f s_ min = Q × f p, f s_ min is lowest sampling frequency, Q is maximum quantity of aliased signals in the frequency band, f p is a subband bandwidth, and performing sampling on the input signal at sampling frequency greater than or equal to the lowest sampling frequency, to obtain a sampled signal; determining a submatrix A Si, corresponding to an observation matrix A for compressive sensing sampling, in each frequency band of the multiple frequency bands according to the signal aliasing pattern in each frequency band of the multiple frequency bands, wherein i =1,..., K; separately restoring a baseband spectrum of the i th ( i =1,..., K) frequency band according to a signal restoration algorithm formula Z S i f = A S i + y f, wherein A S i + is a Moore Penrose inverse, matrix of a submatrix A Si of the i th frequency band, Z Si ( f) is the restored baseband spectrum of the i th frequency band, y ( f) is a discrete Fourier transformation of the sampled signal, and K is a total quantity of the frequency bands that are formed on the baseband spectrum; and splicing the restored baseband spectrums of the frequency bands, to obtain the entire baseband spectrum of the input signal, and restoring the input signal according to the baseband spectrum obtained through splicing.