Performance Analysis of 2-D Optical Codes with Arbitrary Cross-Correlation Values under the Chip-Asynchronous Assumption

In this letter, the performance of two-dimensional (2-D) optical codes in incoherent optical code-division multiple-access systems is analyzed without the traditional pessimistic chip-synchronous assumption. We apply a combinatorial method for a more accurate analysis, which can be generalized to 2-D optical codes with arbitrary maximum cross-correlation values. As numerical examples, the performances of 2-D optical codes with the maximum cross-correlation values of one and two are compared under the chip-synchronous and chip-asynchronous assumptions