Complementary FIR Filter Pair for Distributed Impairment Compensation of WDM Fiber Transmission

A method of designing a complementary filter pair is proposed to reduce error accumulation in the split-step backward propagation for distributed impairment compensation of wavelength-division-multiplexing transmission. The complementary filter pair is designed so that the individual errors of the two filters cancel each other. A 12 times 100 Gb/s 16-ary quadrature amplitude modulation transmission system in nonzero dispersion-shifted fiber is simulated using such a filter pair. The required filter length is halved by the complementary filter pair design for a transmission distance of 1200 km.