SCMA detection method for multi-sampling-point joint detection based on MPA

The invention relates to the technical field of wireless communication, and discloses a multi-sampling-point joint detection SCMA detection method based on MPA, which comprises the following steps: S1, signal preprocessing: sampling point extraction is carried out on an oversampling signal of a base station receiving end according to user time delay information associated with the oversampling signal to obtain a preprocessed signal; s2, initial probability calculation: calculating an initial probability value of the preprocessed signal to obtain an initial probability value of a corresponding function node; s3, updating the function node: based on the initial probability value, updating the probability of the message transmitted to the function node by the variable node; s4, updating the variable node: normalizing the probability value of the message transmitted to the variable node by the function node, and then transmitting to the function node; s5, repeating the steps S3 and S4 until the iterative update o