Satellite Internet of Things multi-user uplink transmission scheme based on Chirp spread spectrum technology

The invention provides a satellite internet of things multi-user uplink transmission scheme based on a Chirp spread spectrum technology, which comprises the following steps of: establishing an uplink transmission system model which comprises a user information end, a Chirp spread spectrum modulation module, a repeated operation module, a summation module, a channel module, a chirp demodulating module, a superposition operation module and an incoherent demodulation module which are connected in sequence; and a selective repeated transmission and superposition receiving strategy based on the time diversity technology is provided. Specifically, a sending end carries out Chirp spread spectrum modulation of different spread spectrum factors on each piece of user information in sequence, a receiving signal is obtained through a channel after repeated operation and summation, and a receiving end carries out de-chirp operation, superposition operation and incoherent demodulation on the receiving signal in sequence to