Constructions of Optimal Optical Orthogonal Codes with Weights Set 5,7 via Cyclic Packing

Double-weight optical orthogonal codes are variable-weight optical orthogonal codes (OOCs), which have been widely applied in optical networks and systems. Some works have been devoted to optimal n , W , 1 , Q -OOCs with max w : w ∈ W ≤ 6 . So far, there is no explicit construction of optimal n , W , 1 , Q -OOCs with W = 5,7 . It is known that heavier-weight codewords have better code performance than lighter-weight codewords. So, in this paper, we use cyclic packing to construct two infinite classes of optimal OOCs with weights set 5,7 explicitly, for any prime p ≡ 3 mod 4 and p ≥ 7 . In addition, for 1 ≤ t < p − 1 / 2 , by breaking t blocks of size 7 into 3 of 31 p , 5,7 , 1 , 1 / 2 , 1 / 2 -OOCs and 41 p , 5,7 , 1 , 2 / 3 , 1 / 3 -OOCs, we obtain new infinite classes of optimal 31 p , 3,5,7 , 1 , 7 t / p − 1 + 6 t , p − 1 / 2 p − 1 + 6 t , p − 1 − 2 t / 2 p − 1 + 6 t -OOCs and 41 p , 3,5,7 , 1 , 14 t / 3 p − 1 + 4 t , 2 p − 1 / 3 p − 1 + 4 t , p − 1 − 2 t / 3 p − 1 + 4 t -OOCs, respectively.

Performance Investigation of 2-D Optical Orthogonal Codes for OCDMA

In this paper, comparative analysis of code performance of dissimilar optical 2-D codes from Optical Orthogonal code family has been studied. Optical 2-D codes considered from OOC family are (n,w,1,2) OOC, SPS/OOC, OCFHC/OOC, EPC/OCS and VWOOC. By utilizing hard limiting error probability (HEP) equations and combinatorial method, code performance of each considered code is evaluated in detail. On the basis of detailed comparative performance analysis, EPC/OCS is concluded as best performing codes among all other optical codes under consideration. EPC/OCS possesses much better correlation properties, along with lower hit probability values which are responsible for its supremacy in performance characteristics to the other OOCs considered.