Data sending and receiving method, apparatus, and device, and computer readable storage medium

A data receiving method, comprising:

• receiving the data sent by a first transmission frequency band;
• extracting extended data with a number of 2K on 2K spaced sub-carriers of the first transmission frequency band;
• and
• dividing the extracted and extended data with the number of 2K respectively by corresponding extended elements in an extended sequence with a length of 2K.

A data sending method, comprising:

• in a case where a transmission frequency band sends data by adopting an extended sequence modulation data sending rule, multiplying data to be transmitted on the transmission frequency band respectively by each extended element in an extended sequence with a length of 2K to obtain extended data with a number of 2K, wherein there is another extended element with a phase difference of π relative to each extended element in the extended sequence;
• and
• sending the extended data with the number of 2K on 2K consecutive sub-carriers of the transmission frequency band;
• wherein K is a positive integer greater than 1.