A signal processing method, wherein the method comprises: obtaining, by an optical receiver, a to-be-processed signal block obtained through analog-to-digital conversion processing; determining, by the optical receiver, a prediction signal block corresponding to the to-be-processed signal block; determining, by the optical receiver, a noise compensation coefficient of the to-be-processed signal block based on the to-be-processed signal block and the prediction signal block; and performing, by the optical receiver, noise compensation on the to-be-processed signal block based on the noise compensation coefficient, characterized in that the to-be-processed signal block comprises R 1 to R n, and R 1 to R n are n symbols transmitted in a time sequence, wherein n is an integer greater than or equal to 2; and the determining, by the optical receiver, the noise compensation coefficient based on the to-be-processed signal block and the prediction signal block comprises: obtaining, by the optical receiver, R n + 1 to R n + m - 1, wherein R n + 1 to R n + m - 1 are m-1 symbols following R n that are transmitted in a time sequence; determining, by the optical receiver, a first matrix and a second matrix, wherein the first matrix is [ S 1 S 2... S n], the second matrix is R 1 R 2 R 3...... R n R 2 R 3 R 4...... R n + 1 R 3......... R m R n + m − 1, and S 1 to S n are n symbols comprised in the prediction signal block and transmitted in a time sequence; and each column of the second matrix comprises an initial symbol of the column and m-1 symbols related to the initial symbol in the to-be-processed signal block, wherein n is greater than m, and m is an integer greater than 1; and multiplying, by the optical receiver, the first matrix by an inverse matrix of the second matrix, to obtain a noise compensation matrix comprising the noise compensation coefficient, wherein the noise compensation matrix is [ h 1, h 2...... h m]. obtaining, by an optical receiver, a to-be-processed signal block obtained through analog-to-digital conversion processing; determining, by the optical receiver, a prediction signal block corresponding to the to-be-processed signal block; determining, by the optical receiver, a noise compensation coefficient of the to-be-processed signal block based on the to-be-processed signal block and the prediction signal block; and performing, by the optical receiver, noise compensation on the to-be-processed signal block based on the noise compensation coefficient, characterized in that the to-be-processed signal block comprises R 1 to R n, and R 1 to R n are n symbols transmitted in a time sequence, wherein n is an integer greater than or equal to 2; and the determining, by the optical receiver, the noise compensation coefficient based on the to-be-processed signal block and the prediction signal block comprises: obtaining, by the optical receiver, R n + 1 to R n + m - 1, wherein R n + 1 to R n + m - 1 are m-1 symbols following R n that are transmitted in a time sequence; determining, by the optical receiver, a first matrix and a second matrix, wherein the first matrix is [ S 1 S 2... S n], the second matrix is R 1 R 2 R 3...... R n R 2 R 3 R 4...... R n + 1 R 3......... R m R n + m − 1, and S 1 to S n are n symbols comprised in the prediction signal block and transmitted in a time sequence; and each column of the second matrix comprises an initial symbol of the column and m-1 symbols related to the initial symbol in the to-be-processed signal block, wherein n is greater than m, and m is an integer greater than 1; and multiplying, by the optical receiver, the first matrix by an inverse matrix of the second matrix, to obtain a noise compensation matrix comprising the noise compensation coefficient, wherein the noise compensation matrix is [ h 1, h 2...... h m]. obtaining, by the optical receiver, R n + 1 to R n + m - 1, wherein R n + 1 to R n + m - 1 are m-1 symbols following R n that are transmitted in a time sequence; determining, by the optical receiver, a first matrix and a second matrix, wherein the first matrix is [ S 1 S 2... S n], the second matrix is R 1 R 2 R 3...... R n R 2 R 3 R 4...... R n + 1 R 3......... R m R n + m − 1, and S 1 to S n are n symbols comprised in the prediction signal block and transmitted in a time sequence; and each column of the second matrix comprises an initial symbol of the column and m-1 symbols related to the initial symbol in the to-be-processed signal block, wherein n is greater than m, and m is an integer greater than 1; and multiplying, by the optical receiver, the first matrix by an inverse matrix of the second matrix, to obtain a noise compensation matrix comprising the noise compensation coefficient, wherein the noise compensation matrix is [ h 1, h 2...... h m].