On The Performance of The Effects of Temperature Variation in Ultrafast Incoherent Fiber-Optic CDMA Systems With SOA-Based Tunable Dispersion Compensator

Abstract

Recent studies show that temperature variation in ultrafast incoherent fiberoptic code-division multiple-access (FO-CDMA) systems using picosecond multiwavelength codes is a realistic problem even though dispersion-compensating fiber is utilized. The phenomenon creates distortions in auto-and cross-correlation functions and then worsens system performance. A physical-layer mitigation approach has been reported by using a recently demonstrated semiconductor-optical-amplifier-based tunable dispersion compensator to fully recover the auto-correlation peaks. Applying the concept of "chip granularity" to account for the effects of temperature variation to the cross-correlation functions, this paper formulates a new performance-analytical model for such FO-CDMA systems. The model also supports adjustable quality-of-services through code weight control.

On the Use of SOA-Based Tunable Dispersion Compensator in Ultrafast Incoherent Fiber-Optic CDMA Systems Under Temperature Variation

“…While the cross-correlation functions (from interfering codewords) are also distorted by the FTV time skew and dispersion [6], [7], they generally have much lower power and thus fail to trigger the gain-compression mechanism of the SOA-TDC. The deleterious effect of these distorted cross-correlation functions to the ultrafast incoherent FO-CDMA system performance need to be quantified and modelled accordingly.…”

“…The deleterious effect of these distorted cross-correlation functions to the ultrafast incoherent FO-CDMA system performance need to be quantified and modelled accordingly. As studied [6], [7], the envelope of the kth wavelength of the multiwavelength pulses from the picosecond supercontinuum laser under FTV can be modelled as…”

“…The deleterious effects of fiber temperature variation (FTV) to ultrafast incoherent fiber-optic code-division multiple-access (FO-CDMA) systems using picosecond multiwavelength codes have recently been studied [1]- [5]. Causing dispersion and time skew to these multiwavelength codes, FTV can distort the auto-and crosscorrelation functions seen at receivers and thus create detection errors in transmitted data bits [6], [7]. In addition, chromatic dispersion (CD) accumulated in a long fiber link requires the application of dispersion compensating fiber (DCF).…”

“…Besides completely eliminating the residual CD, Ahmed, et al [3]- [5] proposed a semiconductor-optical-amplifier (SOA)-based tunable dispersion compensator (TDC) to compensate for the FTV distortion to the autocorrelation function, however, not to the cross-correlation function. To account for the effect of the FTV-distorted cross-correlation function (at the SOA-TDC output) to the performance of this kind of FO-CDMA systems, new analytical models were studied [6], [7].…”

“…The deleterious effects of FTV to this system are studied and quantified in terms of "chip granularity" [3]. In Section 3, a recent multiple-quality-of-service (QoS) analytical model [7] is applied to study the performance of this FO-CDMA system with different amounts of FTV (in terms of chip granularity) and QoS (in terms of code weight).…”