The invention provides a brain-computer interface decoding method and
system based on multi-
modal signal fusion, and relates to the technical field of brain-computer interfaces. The method comprises the following steps: S1, acquiring a multi-mode
signal, unifying a time reference and starting a sliding
window detection intention; s2, de-prompting, sequential bias checking and permutation correction,
artifact suppression and band-pass filtering are carried out; s3, channel and
modal quality is calculated, and a reliability weight and a rejection
list are generated and marked; s4, multi-scale coding is carried out, cross-
modal alignment is realized through learnable time
delay compensation, and a first fusion representation is obtained; s5, performing layering and cross attention fusion under reliability gating so as to align and reconstruct constraint to keep
semantic consistency, and obtaining joint
semantic representation; and S6, sequence-level decoding is carried out to output
semantics / states / instructions. According to the method, bias and
noise are suppressed, time
delay difference and cross-main-body equipment change are resisted, and decoding accuracy, robustness and practicability are remarkably improved.