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This paper proposes a novel design of an integrated multi-arm power splitter based on photonic crystal waveguides. A 1 × 5 power splitter is proposed by introducing line defects to form a one input waveguide arm and five output waveguide arms. The plane wave expansion method (PWE) is used to investigate the dispersion characteristics of the light coupling between the guided modes in the photonic band gap (PBG) from 0.037 ω/2πc to 0.095 ω/2πc frequency range. Using Finite-Difference Time Domain (FDTD) method, we calculated the power splitting across each output arm; 52.2% in arm C, 16.9% in arm D, 14.6% in arm E, 12.1% in arm A and 3.4% in arm B. The total observed transmission efficiency of the splitter is 99.2%. Further, the time response of electric field along the Y direction (Ey) which is perpendicular to the X-Z plane is studied. The output arms C, E, D and B show beam shaped envelope response while the remaining output arm A exhibit negligible variation with time. The compact and low cost proposed design contributes to the state of art progress in the field of photonics integrated circuits (PICs) technology where the power splitter plays a prominent role of splitting optical power between all the optical elements integrated in the chip. [ABSTRACT FROM AUTHOR]

In this paper, we have investigated wavelength division multiplexed (WDM) hybrid (ring-tree-star) topology. Eight optical add/drop multiplexers (OADMs) are used to make ring structure. The single mode fiber and dispersion compensating fiber and semiconductor optical amplifier (SOA) are employed between each OADM to achieve a maximum. To increase the number of users each OADM node of ring network is connected to star and tree network topology which can accommodate more than 2048 users. Various system parameters (for different channel spacing, different input power signal, different data rates and the fiber length) are varied to investigate the system performance in the term of BER and Q factor. [ABSTRACT FROM AUTHOR]

In this paper, the performance of bi-directional passive optical network (BPON) has been evaluated and compared at different bit rates in the scenario of triple play service. The triple-play service is realized as a combination of data, voice and video signals. This architecture is investigated for symmetrical data traffic for uplink and downlink transmission and its performance is also evaluated in terms of Q -factor and eye height at different transmission distance. The Q -factor results show the acceptable performance at 10 Gbps data rate for downstream and upstream transmission, as it accommodates 128 optical network units (ONUs). Further the proposed system's performance is compared with the current state-of-the-art PON architectures. [ABSTRACT FROM AUTHOR]

In this paper, the cost effective bi-directional passive optical network architecture with wavelength remodulated scheme is investigated. To realize the cost-effective PON, remodulation scheme is used, in which the downstream optical signal is reused as a carrier for the upstream transmission as it eliminates the need for an extra laser source at optical network units. The performance of proposed passive optical network is analyzed and compared for various modulation formats such as Non Return to Zero (NRZ), Return to Zero (RZ) and On–Off Keying (OOK) with 64 optical networks units (ONUs) at different traffic speed for downlink and uplink, respectively. It has been observed that the most suitable data format for proposed PON network is NRZ. Further the proposed system performance is compared with the current state-of-the-art PON architectures. [ABSTRACT FROM AUTHOR]

A simple genetic algorithm is implemented to perform multi parameter optimization of Raman Fiber Amplifier for 100 channel S band dense wavelength division multiplexed system at 25 GHz interval. A cost effective system using single Raman pump is investigated aiming at maximum average gain. The single counter propagating pump is optimized to frequency of 211.528 THz and 652.93 mW power level with optimum Raman fiber length of 44.064 Km. There is evidence to show that the optimum solution presents a small gain variation (less than 3 dB) over an effective bandwidth covering 197–199.475 THz. The optimized configuration enabled an adequate system performance in terms of acceptable Q -factor (19.52 dB) and BER (1.46 × 10 −21 ). [ABSTRACT FROM AUTHOR]

Abstract: In this paper, four modulation formats including nonreturn-to-zero (NRZ), nonreturn-to-zero raised cosine (NRZ-RC), return-to-zero (RZ), return-to-zero raised cosine (RZ-RC) DWDM system with different hybrid optical amplifiers are introduced. We show that NRZ-DPSK and RZ-DPSK degrade the performance when Raman amplifier is considered. The obtained results reported that RZ and RZ-RC DWDM system with Raman-EDFA provide better results and cover 1512 and 1260km of transmission distance, respectively, with acceptable quality factor (>15dB) and bit error rate (<10−9). Further, it is also confirmed that using the hybrid optical amplifiers is a best alternative to increase the span distance. [Copyright &y& Elsevier]

Abstract: In this paper, we investigate pre-, post-, symmetrical dispersion and power compensation in parallel for 96 channels×10Gbps non-return to zero DWDM system using pumped dispersion compensating fiber (PDCF) and pumped single mode fiber (PSMF). The results of three compensation methods have been compared in the term of bit error rate, eye closure penalty and Quality factor and it is found that both post-, and symmetrical compensation methods are provide better results for short haul communication but for long haul communication post-compensation method is the best alternative among other. The impact of bit error rate and eye closure penalty is also observed for large transmission distances and cover 420km using post-compensation method with acceptable bit error rate (2.3×10−10) and eye closure (1.73dB). [Copyright &y& Elsevier]

Abstract: In this paper 10Gbps WDM systems at 16, 32 and 64 channels have been investigated with EDFA, RAMAN and SOA amplifiers individually and the performance has been compared on the basis of transmission distance and dispersion with and without nonlinearities. It is demonstrated that when the dispersion is 2ps/nm/km and the number of channels are less, then SOA provide better results because as we increases the number of channels, the gain saturation problem arises due to cross gain modulation, the cross phase modulation and four wave mixing. When dispersion is increased from 2 to 10ps/nm/km, EDFA provides better results than SOA in the term of BER and output power, but it shows non-uniform gain spectrum. We also observed that RAMAN amplifier provides better results for L band amplification and gain flatting issue because it can substantially reduce the impact of fiber nonlinearity. [Copyright &y& Elsevier]

Abstract: In this paper, we investigated the performance of multi terabits DWDM system consisting of hybrid optical amplifier RAMAN-EDFA for different data format such as non-return to zero (NRZ), return to zero (RZ) and differential phase shift keying (DPSK). We find that in 64×10 and 96×10Gbps, RZ is more adversely affected by nonlinearities, where as NRZ and DPSK is more affected by dispersion. We further show that RZ provide good quality factor (13.88dB and 15.93dB for 64 and 96 channels), less eye closure (2.609dB and 3.191dB for 64 and 96 channels) and acceptable bit error rate (3.89×108 and 1.24×109 for 64 and 96 channels) at the respective distance as compare to other existing modulation format. We further investigated the maximum single span distance covered by using existing data formats. [Copyright &y& Elsevier]

Abstract: In this paper, we investigated the post-, pre- and symmetrical power compensation methods for a different position of hybrid optical amplifier RAMAN–EDFA in fiber link. The effect of increase in signal input power for three power compensation methods is compared in terms of bit error rate, eye closure penalty and output received power. It is found that the post power compensation method is superior to pre- and symmetrical power compensation methods. Further, the effect of variation in length of the standard single mode fiber and dispersion-compensated fiber for three power compensation configurations has also been observed. We observed that RAMAN–EDFA as post power compensation method provides least bit error rate (10−40) and high output power (12dBm) at −15dBm signal input power at fiber link. [Copyright &y& Elsevier]

In this paper, we have investigated the wavelength division multiplexed (WDM) system using ring network topology. This network is used to increase the capacity with eight optical add/drop multiplexers (OADMs) by using dispersion compensating fiber and semiconductor optical amplifier (SOA) to achieve a distance up to 1600 km. It is observed that network shows the acceptable results at 15 Gbps data rate with 100 GHz channel spacing. The OADM nodes are also varied to investigate the network performance in the term of BER and Q -factor. [ABSTRACT FROM AUTHOR]

The performance of DWDM ring network topology is investigated with 13 × 15 Gbps channels without using dispersion compensating fiber among the 3 channels are added and droped using OADM, respectively. Each OADM node having 70 km distance between each other. This ring network topology is evaluated by considering the signal quality factor and BER for different input power at all nodes. Further, this ring network topology is also investigated for different data rate at all nodes. [ABSTRACT FROM AUTHOR]

In this paper, two stage hybrid optical amplifier (HOA) composed of a single erbium doped fiber amplifier and Raman amplifier is proposed for dense wavelength division multiplexed (DWDM) system and investigate the impact of reduced channel spacing. The performance has been evaluated in the term of gain, gain flatness and noise figure. Also, using gain equalization technique, hybrid optical amplifier that has a gain flatness of 3 dB, and a noise figure of less than 7.4 dB is observed. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the performance of optical/hybrid optical amplifier for 64×10Gbps dense wavelength division multiplexed system has been compared. It is observed that hybrid optical amplifier (RAMAN–EDFA) provides better results as compared to conventional amplifiers. The impact of modulation formats (NRZ, RZ and DPSK) on hybrid optical amplifier has been further investigated and it is found that 64×10, RZ is more adversely affected by nonlinearities, where as NRZ and DPSK is more affected by dispersion. [Copyright &y& Elsevier]