Proposed is a method for a terminal to decode a signal. In particular, the method for a terminal to decode a signal comprises: a step for demodulating a first low density parity check (LDPC)-coded signal; and a step for decoding a second signal obtained from the first demodulated signal through a trained neural network. The second signal is obtained by using: an output sequence generated on the basis of the trained neural network; and a log likelihood ratio (LLR) sequence of the first signal.