The invention discloses a time division duplex multi-carrier synchronous transmission method based on 5G, which relates to the technical field of communication, and comprises the following steps of: establishing a carrier mapping table, respectively mapping a plurality of logic carriers to predefined physical resource blocks, and marking uplink and downlink
switching time slots according to a time division mode; after a user terminal receives a
synchronization signal, alignment is carried out through a high-precision local
clock and the reference time of a main
base station, and a synchronization reference point is recorded with a
nanosecond-level
time resolution. According to the invention, through the dynamic synchronization control and
frequency domain interference suppression technology, the synchronization stability and the
data transmission reliability in a high-speed scene are significantly improved; a synchronous load scoring mechanism is introduced to realize efficient scheduling and conflict avoidance of synchronous resources in a multi-user concurrent environment; and in combination with interference
weight estimation and an adaptive filtering strategy, the anti-interference capability and environment adaptability of the
system are effectively enhanced, and the requirements of key services such as
the Internet of Vehicles and industrial control on low-
delay and high-reliability communication are comprehensively met.