Abstract— In this paper, bit error probability of optical CDMA systems employing equal weight orthogonal (EWO) signaling and active correlator in the presence of single optical hard limiter (SHL) is investigated. The performance of mentioned systems, i.e. EWO-SHL systems, is analyzed under the Gaussian approximation of avalanche photo diode (APD) output where the effects of APD noise, thermal noise and interference are included. The effect of receiver’s power splitting ratio deviation from its ideal value on the performance of system is also studied. Moreover, the effect of dissimilarity between two APD parameters on the system performance is conducted. Concisely, this investigation shows that how the performance of EWO-SHL OCDMA systems using conventional receiver can be degraded when the assumption of perfect receiver parameters is violated.

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