Data acquisition method, device and system

The application relates to a data acquisition method, device and system and is applied to an FPGA data acquisition system. The FPGA data acquisition system comprises an analog-to-digital converter andan IQ demodulation arithmetic unit which are in communication with each other. The FPGA data acquisition system is in communication with an analog signal source. The method comprises: when the analog-to-digital converter acquires an analog signal carrying data information from the analog signal source, the analog signal is converted into a digital signal, and the digital signal is sent to the IQdemodulation arithmetic unit; the IQ demodulation arithmetic unit receives the digital signal, divides the digital signal into a plurality of sequential groups of digital signals, and performs IQ demodulation operation on the plurality of groups of digital signals by adopting a parallel operation mode; the IQ demodulation arithmetic unit combines the demodulation results of the plurality of groupsof digital signals accordi