A Blind Receiver Using Optical Hard-Limiters for Optical Code Division Multiple Access

We propose a receiver using two optical hardlimiters (OHL’s) for optical code division multiple access (CDMA). In the receiver the likelihood ratio test is made by using the photocounts obtained by the intensities in the weighted positions of the signature sequence. Before the test, two OHL’s enable the proposed receiver to remove the effect of the multiaccess interference (MAI), without knowledge of other users: in this sense it is a blind receiver. This blindness leads the proposed receiver to be a much simpler receiver than the multiuser receivers. We analyze the bit error rate (BER) of the proposed receiver in the optical CDMA system using optical orthogonal codes (OOC’s). Some numerical results show that the proposed receiver has better performance compared to the decorrelating receiver, which is one of multiuser receivers.