Energy-Efficient High-Capacity Optical CDMA Networks by Low-Weight Large Code-Set MPC

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.