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Static and Dynamic Characteristics
Series: De Gruyter STEM

Abstracts

Future 5 G networks can enhance their wireless capacity and speed by effectively using high-frequency millimetre waves. Radio over fibres (RoF) is the promising technology to deliver millimetre waves over optical fibres as it integrates radio domain with wireless domain. The current study employed cost-effective non-return to zero scheme to encode 10 Gbps – 60 GHz data and wavelength division multiplexing scheme to transmit four channels over 60 km optical fibre link.

Abstract

A serially coupled double-ring resonator using the low loss multilayer silicon wire waveguide is presented that has featured high out-of-band rejection and high finesse. The round trip loss and Q factor has also been calculated and found moderate. However, extremely low loss waveguide has shown reduced coupling between the ring and the waveguide.

Abstract

This article presents the architecture of optical microring resonator based on surface plasmon polaritons using different profile materials like silicon (Si), silver (Ag) and gold (Au). It is observed that 3.53e-005 w/m, 6.92e-005 w/m, 7.05e-005 w/m received optical powers are achieved in silicon (Si), silver (Ag) and gold (Au) profile materials, respectively, of optical microring resonator at 0.1 w/m minimum input transmission power for 1.55 μm input transmission wavelength. The result shows that the silicon profile is best for designing the optical microring resonator in terms of received optical power.

Abstract

In the evolvement of current passive optical networks (PONs), there is ever increasing bandwidth demand due to dynamic service requirements. This introduces challenge for the choice of multiplexing technique and physical layer bounds like fiber length, data rate, and number of users are critical over a suitable architecture. In this article, hybrid wave division multiplexing-time division multiplexing PON is analyzed using variable length of fiber with data rates up to 40 Gbps over a maximum of 128 end users. Comparative study using different frequency spacing’s has shown that it has negligible effect on the Q-factor performance parameter. Further in the work, variable data rates required for different services is successfully transmitted up to 30 km to 128 number of users for an acceptable level of bit error rate.

Abstract

This article proposed an all-digital code converter schematic. It converts input binary code into gray code output with an operating data rate of 50 Gbps. The design is based on exploiting nonlinear attributes with semiconductor optical amplifier, which is otherwise contemplated as cons if utilized as an amplifier. It is realized with a semiconductor optical amplifier placed symmetrically with both arms of Mach–Zehnder interferometer, and phase modulation occurs amid wings of the Mach–Zehnder structure. Accordingly, numerical simulations have been executed for the applied data inputs. Consequent gray code output patterns have been verified that resemble with theoretical digital logical outcome. Evaluations with design have illustrated impressive optical performance metric extinction factor beyond 10 dB for the imperative constituents and constraints, with semiconductor optical amplifier confine factor beyond 0.3, pump current of 0.4 A, active length of 0.05 mm, and with modulator chirp factor and on–off ratio beyond 0.5 and 10 dB, respectively. Accordingly, this investigation could be an assist for the impending optical computing complex networks for the contemporary digital globe, requiring code conversion as one of the imperative practices.

Abstract

In mode division multiplexing (MDM) free space optical (FSO) communication system, the atmospheric turbulences such as fog, rain, and haze cause adverse effects on system performance. This paper investigates the mitigation of atmospheric turbulences of FSO using MDM and decision feedback equalizer (DFE) with minimum mean square error (MMSE) algorithm. The implementation of the MMSE algorithm is used to optimize both the feedforward and the feedback filter coefficients of DFE. The proposed system comprises three parallel 2.5Gbit/s channels using Hermite–Gaussian modes. A data rate of 7.5Gbit/s over 40 m, 800 m, 1400 m, and 2km under medium fog, rain, haze, and clear weather, respectively, has been achieved. In addition, it is noticed that the link distance is reduced while increasing the attenuation. The simulation results revealed that a DFE improves the performance MDM FSO system while maintaining high throughput and desired low bit error rate.

Abstract

A novel architecture of N×N bidirectional-reconfigurable multiwavelength optical cross connect (B-RMOXC) based on tunable Fiber Bragg grating and optical circulator is proposed. B-RMOXC network is one of crucial network element for wavelength routing in dense wavelength division multiplexing system. This paper presents a high speed, power compensated bidirectional optical cross connect and verified the performance of bidirectionality with 0.8-nm channel spacing having bit rate of 10 Gbps at different transmission distances. Optical signal-to-noise ratio of 36.62 dB and 35.55 dB is achieved with acceptable Quality factor of 6.26 and 6.99 respectively for upstream and downstream at 60 km having input transmission power of −12 dBm. It is found that the data can be communicated bidirectionally to a distance of 60 km in the presence of fiber nonlinearities without optical amplifier.