In this paper, we have proposed a novel spreading code-set based on the prime code families, hereby referred to as “transposed sparse-padded modified prime code” for synchronous optical code-division multiple-access (OCDMA) networks. The proposed code-set is compared with modified prime codes (MPCs) in terms of correlation properties, bit-error rate (BER), and cardinality. This new low-weight large code-set has better correlation characteristics as compared with MPC families and, as results indicated, the new code-set has considerably improved the BER and power consumption of the OCDMA networks. We have analyzed the performance of the proposed code-set in both incoherent ON–OFF keying and pulse position modulation OCDMA systems, while the multiple access interference was the major degrading quality. The results indicate that at the BER floor of 10-9, the proposed code-set can accommodate greater number of users and consume less power as compared with the MPC under the same transmission conditions.
© 2012 IEEE
Jin Qian, M. Massoud Karbassian, and H. Ghafouri-Shiraz, "Energy-Efficient High-Capacity Optical CDMA Networks by Low-Weight Large Code-Set MPC," J. Lightwave Technol. 30, 2876-2883 (2012)