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This paper the construction of the double weight (D\V) code family, one the recent codes for spectral amplitude coding (SAC) is studied. The DW code family is constructed using a matrix construction technique and a mapping scheme to increase the number of users. To obtain a single user's codeword the whole matrix must be constructed. In this paper a simplified equation based construction technique for the DW code family is proposed. This new simplified construction scheme depends on the three basic building blocks for the DW code family. General equations for the codeword construction and code length are given.

To increase the number of users in the double weight (DW) code family, a mapping technique is applied. This mapping technique increases the number of users but at a cost of unfixed cross-correlation property. The complementary detection technique used in spectral amplitude coding (SAC) systems, can completely cancel the multiple access interference (MAI) only if there is a fixed cross-correlation between different code sequences. In this paper we study the performance of the DW code family a alternative detection scheme that can support balance detection for unfixed cross-correlation property. Also a mathematical approach is proposed to reduce the number of fiber Bragg gratings and minimize the phase induced intensity noise.

This paper concentrates on double weight code family as a proposed code for the optical spectrum code division multiple access (OSCDMA) which has one cross correlation value. By eliminating the intersection columns of this code, the cross correlation value will be zero instead of one. This new derived code is called zero cross-correlation code (ZCC) (S. Amar et al., 2006). In ZCC code, the performance is expected to be better than MDW code because it offers low cross correlation value. It is easy to distinguish the desired signal from the interfering signal if the cross correlation value is low. Besides, a general new equation is obtained for code which has zero cross correlation value instead of basic matrix and mapping technique which are used in modified double weight code to obtain a specific code word.