A signal processing apparatus, comprising: a receiving unit, configured to receive an analog signal; a frequency band adjustment unit, configured to adjust a frequency band of the analog signal to a lowest frequency band when the frequency band of the analog signal received by the receiving unit falls outside the lowest frequency band in multiple preconfigured frequency bands; a processing unit, configured to process, by using a signal processing channel in the lowest frequency band, the analog signal whose frequency band has been adjusted to the lowest frequency band by the frequency band adjustment unit; wherein the processing unit comprises: an analog signal splitting subunit, configured to split, according to a preconfigured policy, the analog signal that has been adjusted to the lowest frequency band, so that the analog signal that has been adjusted to the lowest frequency band forms at least two analog sub-signals; a down-conversion processing subunit, configured to perform down-conversion processing on the at least two analog sub-signals obtained by means of splitting by the analog signal splitting subunit; an analog-to-digital conversion subunit, configured to perform analog-to-digital conversion on the at least two analog sub-signals obtained after the down-conversion processing subunit performs down-conversion, so as to form at least two digital sub-signals corresponding to the at least two analog sub-signals; a digital signal aggregation subunit, configured to aggregate, into one digital signal, the at least two digital sub-signals obtained after the analog-to-digital conversion subunit performs analog-to-digital conversion; and wherein the analog signal splitting subunit is configured to determine, according to a sampling rate of an analog-to-digital converter, a quantity of sub-signals into which the analog signal is to be split, and split the analog signal into analog sub-signals of the quantity of sub-signals by using a power splitting/combining network. a receiving unit, configured to receive an analog signal; a frequency band adjustment unit, configured to adjust a frequency band of the analog signal to a lowest frequency band when the frequency band of the analog signal received by the receiving unit falls outside the lowest frequency band in multiple preconfigured frequency bands; a processing unit, configured to process, by using a signal processing channel in the lowest frequency band, the analog signal whose frequency band has been adjusted to the lowest frequency band by the frequency band adjustment unit; wherein the processing unit comprises: an analog signal splitting subunit, configured to split, according to a preconfigured policy, the analog signal that has been adjusted to the lowest frequency band, so that the analog signal that has been adjusted to the lowest frequency band forms at least two analog sub-signals; a down-conversion processing subunit, configured to perform down-conversion processing on the at least two analog sub-signals obtained by means of splitting by the analog signal splitting subunit; an analog-to-digital conversion subunit, configured to perform analog-to-digital conversion on the at least two analog sub-signals obtained after the down-conversion processing subunit performs down-conversion, so as to form at least two digital sub-signals corresponding to the at least two analog sub-signals; a digital signal aggregation subunit, configured to aggregate, into one digital signal, the at least two digital sub-signals obtained after the analog-to-digital conversion subunit performs analog-to-digital conversion; and wherein the analog signal splitting subunit is configured to determine, according to a sampling rate of an analog-to-digital converter, a quantity of sub-signals into which the analog signal is to be split, and split the analog signal into analog sub-signals of the quantity of sub-signals by using a power splitting/combining network. an analog signal splitting subunit, configured to split, according to a preconfigured policy, the analog signal that has been adjusted to the lowest frequency band, so that the analog signal that has been adjusted to the lowest frequency band forms at least two analog sub-signals; a down-conversion processing subunit, configured to perform down-conversion processing on the at least two analog sub-signals obtained by means of splitting by the analog signal splitting subunit; an analog-to-digital conversion subunit, configured to perform analog-to-digital conversion on the at least two analog sub-signals obtained after the down-conversion processing subunit performs down-conversion, so as to form at least two digital sub-signals corresponding to the at least two analog sub-signals; a digital signal aggregation subunit, configured to aggregate, into one digital signal, the at least two digital sub-signals obtained after the analog-to-digital conversion subunit performs analog-to-digital conversion; and wherein the analog signal splitting subunit is configured to determine, according to a sampling rate of an analog-to-digital converter, a quantity of sub-signals into which the analog signal is to be split, and split the analog signal into analog sub-signals of the quantity of sub-signals by using a power splitting/combining network.