Higher-order dispersion mitigation for spectrum-sliced FFH-OCDMA using adaptive prime-hop codes

摘要

The fast frequency hopping optical CDMA with prime-hop codes (PHCs) provides great flexibility and increases spectral efficiency in comparison with direct sequence methods. Applying the spectrum-sliced incoherent source will further reduce the system cost. However, the dispersion in such an incoherent system becomes a limiting factor to the bit error rate. A novel adaptive PHC scheme to such systems is proposed in this article. The main impact of the scheme is to reduce the power loss and the bit error rate (BER) degradation due to higher-order dispersion. The impact of inherit beat noise in spectrum slicing systems is also alleviated. Performance comparisons between the adaptive PHC and original PHC schemes indicate that the former is more suitable for use in the considered incoherent system, accommodating up to 17% more users for a given BER. The proposed adaptive method can be universally applied to mitigate dispersion effects in the similar 2D OCDMA systems.