In an advertising method, a first device generates a first signal, where a modulation type of the first signal is PSK modulation. The first signal sequentially includes a sequence part, a first part, and a second part. The sequence part includes at least one of a predefined sequence, a predefined signal, a preconfigured sequence, and a preconfigured signal. The first part includes first control information encoded by using a polar code. The second part includes first advertisement information. The first device sends the first signal on a first advertisement dedicated frequency hopping channel.