Performance of on-off keying optical code-division multiple access using feedback-controlled spreading sequences

Optical code-division multiple access (OCDMA) using feedback-controlled spreading sequences (FCSSs) (FCSS/OCDMA) is presented. The bit-error rate characteristics of asynchronous FCSS/OCDMA are demonstrated by simulations in the presence of avalanche photodiode noise and thermal noise. The results indicate that FCSS/OCDMA achieves the single-user performance of conventional on-off keying (OOK) OCDMA (OOK-OCDMA) with double optical hard-limiters.