A wakeup method, comprising: performing, by a first signal processing circuit, monitoring at a first frequency while performing, by a second signal processing circuit, monitoring at a second frequency, wherein the second frequency is different from the first frequency; receiving, by the second signal processing circuit, a wakeup signal at the second frequency, wherein a bandwidth of the wakeup signal is less than a first value, the wakeup signal is transmitted by a first electronic device at a plurality of transmit frequencies or at a bandwidth greater than a second value, and the second value is greater than the first value; performing, by the first signal processing circuit, monitoring at the second frequency while performing, by the second signal processing circuit, monitoring at a third frequency, wherein the third frequency is different from both the first frequency and the second frequency; and receiving, by the first signal processing circuit, the wakeup signal at the second frequency; wherein the first signal processing circuit comprises an extremely narrow-band band-pass filter, an envelope detector, a comparator, and a correlator, and the method further comprises: outputting, by the first signal processing circuit, a first logical value, wherein the first logical value is used to indicate that the first signal processing circuit receives the wakeup signal; outputting, by the second signal processing circuit, a second logical value, wherein the second logical value is used to indicate that the second signal processing circuit does not receive the wakeup signal; and determining, by a first logical OR operation circuit based on the first logical value and the second logical value, that the wakeup signal is received. performing, by a first signal processing circuit, monitoring at a first frequency while performing, by a second signal processing circuit, monitoring at a second frequency, wherein the second frequency is different from the first frequency; receiving, by the second signal processing circuit, a wakeup signal at the second frequency, wherein a bandwidth of the wakeup signal is less than a first value, the wakeup signal is transmitted by a first electronic device at a plurality of transmit frequencies or at a bandwidth greater than a second value, and the second value is greater than the first value; performing, by the first signal processing circuit, monitoring at the second frequency while performing, by the second signal processing circuit, monitoring at a third frequency, wherein the third frequency is different from both the first frequency and the second frequency; and receiving, by the first signal processing circuit, the wakeup signal at the second frequency; wherein the first signal processing circuit comprises an extremely narrow-band band-pass filter, an envelope detector, a comparator, and a correlator, and the method further comprises: outputting, by the first signal processing circuit, a first logical value, wherein the first logical value is used to indicate that the first signal processing circuit receives the wakeup signal; outputting, by the second signal processing circuit, a second logical value, wherein the second logical value is used to indicate that the second signal processing circuit does not receive the wakeup signal; and determining, by a first logical OR operation circuit based on the first logical value and the second logical value, that the wakeup signal is received. outputting, by the first signal processing circuit, a first logical value, wherein the first logical value is used to indicate that the first signal processing circuit receives the wakeup signal; outputting, by the second signal processing circuit, a second logical value, wherein the second logical value is used to indicate that the second signal processing circuit does not receive the wakeup signal; and determining, by a first logical OR operation circuit based on the first logical value and the second logical value, that the wakeup signal is received.