Four-user, 2.5-Gb/s, spectrally coded OCDMA system demonstration using low-power nonlinear processing

Abstract

Abstract-This paper describes the demonstration of 2.5-Gb/s four-user optical-code-division-multiple-access (OCDMA) system operating at bit-error rate 10 11 utilizing programmable spectral phase encoding, an ultrasensitive ( 200 fJ/b) periodically poled lithium-niobate-waveguide nonlinear waveform discriminator and 10G Ethernet receiver. A comprehensive description of this ultra-short-pulse spectral phase-coded OCDMA system is presented. On the subsystem level, two key component technologies, namely, femtosecond encoding/decoding and low-power high-contrast nonlinear discrimination, have been developed and characterized. At the system level, data for the four-user OCDMA system operating at 2.5 Gb/s for binary as well as multilevel code families are described.Index Terms-Multiaccess interference (MAI), nonlinear optics, optical code-division multiple access (OCDMA), optical signal processing, pulse shaping.

Multi-user, 10Gb/s spectrally phase coded O-CDMA system with hybrid chip and slot-level timing coordination

“…Our experimental setup is similar to the system used in our prior work [3,4]. A 10 Gb/s PRBS 2 23 -1 data stream is impressed on the ∼0.4 ps, 10 GHz mode-locked fiber laser output.…”

“…Optical code division multiple access (O-CDMA) is receiving increased attention due to its potential for local area network application [1][2][3][4][5][6][7][8]. In O-CDMA, multiple access is achieved by assigning different, minimally interfering code sequences to different transmitters, which must subsequently be detected in the presence of multi-access interference (MAI) from other users.…”

“…The ability to operate at low power per user is critical for scaling O-CDMA to greater numbers of users. In multi-user networking each receiver will see a sample of each of the multiple-access signals; therefore, the required amplifier saturation power scales with the number of users (as well as bit rate) [2,3].…”

Reduction of Multiple Access Interference in OCDMA Systems Using a Semiconductor Based TPA Device

“…Alternatively, nonlinear thresholding can be used to suppress M\AI while allowing properly decoded pulses through. Examples of such nonlinear thresholding devices are nonlinear optical loop mirrors (NOLM) and periodically poled lithium niobate (PPLN) fibres [3,4]. In this paper, we present a semiconductor based nonlinear thresholder and detector based on two-photon absorption (TPA) for use in an OCDMA system.…”

Sistemas ópticos incoherentes para la generación de señales arbitrarias basados en filtros fotónicos de microondas

“…2.12(a) se presenta un ejemplo con una secuencia de pulsos de anchura 200 fs. La aplicación más directa de este tipo de señales son las comunicaciones de datos, por ejemplo mediante una codificación en fase de los diferentes bits de información con cada uno de los pulsos [90,91]. No obstante, estas señales también encuentran aplicación en otros muchos campos como son el control de reacciones químicas y el movimiento molecular [92] o la microscopia y la captura de imágenes [93,94].…”