METHOD AND APPARATUS FOR TESTING OPTICAL FIBER BY USING BIORTHOGONAL CODES AND MOORE-PENROSE GENERALIZED INVERSES

摘要

An optical fiber measuring method and apparatus using a biorthogonal code and a moore-penrose inverse matrix are provided to improve the SNR(Signal to Noise Ratio) by coding optical pulse by the biorthogonal code and to measure the size of an optical signal. An optical fiber measuring method an optical fiber using a biorthogonal code and a moore-penrose inverse matrix comprises: a step of setting i as 1 and setting the final measurement value(S200); a step of coding optical pulse according to an i-th codeword of n bit biorthogonal code matrix and injecting to the optical fiber(S210); a step of measuring an i-th optical signal generated when the coded optical pulse is reflected at the optical fiber and storing in the memory(S220); a step of recovering n numbers of signals by multiplying each of n elements of an i-th row matrix and the i-th optical signal of the moore-penrose inverse as to the n bit biorthogonal code matrix(S250); a step of moving the n signals on time-axis and removing the time difference between the n signals(S260); a step of obtaining the average of n signals with time-axial movement and calculating an i-th measurement value(S270); a step of adding the i-th measurement value at the final measurement value, renewing the final measurement value, storing the final measurement value at the memory, and removing the i-th optical signal from the memory; and a step of comparing whether the i is 2n or not, adding 1 to the i if the i is small, going on the S210,S220 steps, and considering the value finally stored in the memory as the final measurement value if the i is 2n.