Performance analysis of multiwavelength OOCDMA fiber-optic networks

Abstract

The performance of multiwavelength optical orthogonal code-division multiple-access (OOCDMA) communication networks is investigated. The basic network is assumed to consist of a number of multiwavelength laser sources coupled into a graded-index multimode fiber which is in turn coupled to avalanche photodiode (APD) receivers. The analysis involves the determination of error probability of the network taking the effects of laser phase noise, modal noise, multiple-user interference and receiver noises into account. The error performance of a three-wavelength (case 1) fiber-optic network is compared with that of a four-wavelength (case 2) network considering the same number of users in both networks. From the analysis, it is observed that: (a) case 1 (case 2) is better than case 2 (case 1) when the received laser power P s is low (high); and (b) when the power is medium, case 1 (case 2) is better when the modal parameter is large (small). It is also found that the effect of modal noise is dominant when P s is large, while the effect of laser phase noise is dominant when P s is small.