Bluetooth sbc is a coded connection mode. Sbc is the floorboard of subband coding and the earliest format, which means subband coding in Chinese. SBC is the mandatory coding format of Bluetooth audio transmission protocol, and all Bluetooth will support this protocol. The bit rate of Bluetooth sbc is similar to that of mp3. Bluetooth will not encounter interference from other factors during data transmission. If Bluetooth is too far away from the connected device, it will automatically disconnect, which is one of the more humanized functions. However, due to not transcoding directly from the mobile phone, data may be lost when transmitting data, resulting in poor sound source. Working principle: firstly, the input signal is divided into several sub-band signals with different frequency bands through a set of band-pass filters, and then these signals are converted into baseband signals through frequency shift, and then sampled separately. Quantize and encode the sampled signal, synthesize the total code stream and send it to the receiving end. At the receiving end, the code stream is first divided into sub-band code streams corresponding to atomic band signals, and then the spectrum is decoded and moved to the original position. Finally, the reconstructed signal is obtained by band-pass filtering and addition.