Repeater Spacing Research Articles

Four wave mixing, average amplified spontaneous emission, and channel spacing effects on the optical transceiver systems based on multi pumped Raman amplifiers

Abstract This study has clarified the four-wave mixing, average amplified spontaneous emission, and channel spacing effects on the optical transceiver systems based on multipumped Raman amplifiers. The employed spectral width is applied in the fiber core from 1450 nm to 1650 nm through the subgroups in the fiber link. The optical loss and fiber dispersion effects are demonstrated with the spectral wavelength band with different pumping levels. The optical loss is clarified in relation to different laser pumping levels and different number of links per fiber core channel at 1550 nm. As well as the dispersion factor is demonstrated in relation to different laser pumping levels and different number of links per fiber core channel at 1300 nm. Extended fiber length, amplifier gain, and repeater spacing are clarified with different laser pumping levels and different number of links variations per fiber core channel at 1550 nm. The data rate transmission is studied against different laser pumping levels and different number of links variations per fiber core channel at both 1550 nm and 1300 nm. The optimum fiber coupled power is demonstrated against different laser pumping levels and different number of links variations per fiber core channel at 1550 nm. The fiber coupling efficiency is studied and demonstrated against different laser pumping levels and different number of links variations per fiber core channel at 1550 nm.

Design and analysis of high-speed data optical fiber communication system through EDFA amplifier system

Abstract This study presented design and analysis of high-speed data optical fiber communication system through EDFA amplifier system. The design with practical data for parameters to maximize the transmission bit-rate is clarified. The bit rate distance product can be optimized for the improvement of performance of high-speed long haul repeater spacing with amplification technique. The basic amplification system for optical fiber communication system is clarified. Transmitter/receiver components with the circuit connections and the operation are also indicated in details. The practical circuit model of the transmitter and receiver are designed clearly in this work. The design of distribution maps to measure the Q factor and minimum bit error rate and many different simulation models for applied to achieve high-speed data optical fiber communication system.

On Single-Wire Power Line Microwave Communication Using Low-Loss Modes

Using only the thin-wire approximation, a closed-form solution for the current induced on an infinitely long conductor by a voltage source or an electric dipole in close proximity was found. For lossy conductors, the current consists of a continuous spectrum of radiation modes and a low-loss discrete mode, the Sommerfeld–Goubau (SG) mode. While the relative magnitude of these two components is sensitive to frequency and wire conductivity, the total current is nearly the same as for a perfect conductor over distances comparable to power line communication repeater spacing. For observation points not near the source, the current induced by the voltage and dipole sources differs only by a known constant. Hence, it is possible to use total current expressions from antenna theory to evaluate the performance of power line communication systems. These are used to show the advantage of a single-conductor communication channel to that of a wireless channel using high-gain antennas.

The Communication by Means of the Optical Fiber

A fiber optics is a transparent, flexible fabric made of plastic or glass with a diameter slightly bigger than human hair. It's mostly used to transmit light from one fiber end to the other. This kind of transmission is often used in fiber optic communication, where an optic fiber link delivers data over a longer distance and with a higher bandwidth than an electrical line. The optical fiber communication system and network is now undergoing a significant transformation from a static, scalable, energy-efficient, and flexible design to a dynamic, scalable, energy-efficient, and adaptable approach. We look at the evolution of optical network technologies and methods in the fifth century in this article. The fibre optics biosensor is extremely important in the production of biosensors since it helps to quickly miniaturise and integrate those targets. Fiber optics has advanced dramatically since the fourth generation, with data rates reaching 40-60 tbps, repeater spacing reaching 35000 km, and wavelengths reaching 1.5 micrometres.

Upgrading superior operation performance efficiency of submarine transceiver optical communication systems toward multi tera bit per second

This paper shows the enhancement of performance operation efficiency of submarine optical communication systems toward multi Tb/s. The performance and cost optimization within transceiver submarine communication system requires careful balancing of single mode fiber attributes. Commercial single mode optical fibers are employed for this task, which that are namely Vascade® L1000 fiber, Vascade® LS+ fiber, Vascade® LEAF® fiber, Vascade® S1000 fiber, Vascade® EX 1000 fiber, and Vascade® EX 3000 fiber. High transmission capacity and long distance repeated submarine systems are achieved with attenuation and dispersion managed solutions as well as the effects of water depth, water pressure, and water temperature are taken into account in this study. The importance of minimizing dispersion slope within choosing suitable hybrid commercial submarine optical fibers to ensure good channel performance and wide system bandwidth. Vascade® R1000 fiber (mixed Vascade® L1000 fiber plus Vascade® S1000 fiber) that is namely dispersion managed fiber (DMF) offers a solution for high submarine system capacity. The figure of merit, cost planning budget, average repeater spacing, and possible transmission bit rate are the key solution for the trade off different commercial submarine optical fibers.

Hybrid quantum repeater for qudits

We present a "hybrid quantum repeater" protocol for the long-distance distribution of atomic entangled states beyond qubits. In our scheme, imperfect noisy entangled pairs of two qudits, i.e., two discrete-variable $d$-level systems, each of, in principle, arbitrary dimension $d$, are initially shared between the intermediate stations of the channel. This is achieved via local, sufficiently strong light-matter interactions, involving optical coherent states and their transmission after these interactions, and optical measurements on the transmitted field modes, especially (but not restricted to) efficient continuous-variable homodyne detections ("hybrid" here refers to the simultaneous exploitation of discrete and continuous variable degrees of freedom for the local processing and storage of entangled states as well as their non-local distribution, respectively). For qutrits we quantify the light-matter entanglement that can be effectively shared through an elementary lossy channel, and for a repeater spacing of up to 10 km we show that the realistic (lossy) qutrit entanglement is even larger than any ideal (loss-free) qubit entanglement. After including qudit entanglement purification and swapping procedures, we calculate the long-distance entangled-pair distribution rates and the final entangled-state fidelities for total communication distances of up to 1280 km. With three rounds of purification, entangled qudit pairs of near-unit fidelity can be distributed over 1280 km at rates of the order of, in principle, 100 Hz.

OPTIMALISASI HMI SCADA UNTUK MONITORING DAN KONTROL REPEATER RADIO KOMUNIKASI MENGGUNAKAN MODEM GPRS INTEK J65i-X

Al Anamila Nur Aufa, Teguh Yuwono, in paper SCADA HMI optimization for monitoring and control repeater using radio communication modem GPRS INTEK J65i–X explain that radio communications at PT PLN ( Persero ) APD Central Java and Yogyakarta is still a major communication medium for coordinating the work , both maintenance and handling of interference between units . Repeaters in this case an important role in the communication process between APD dispatcher JTY with Area - Area and officers in the field because of the presence of the communication range of the repeater spacing becomes wider . In operation repeaters can be susceptible to interference that can result in radio communications in the areas covered by the repeater to be disrupted so that the communication between the dispatcher APD JTY with Area - Area and field workers to be blocked. Handling repeater for this disorder is not maximized due to the lack of real time monitoring of the state of the repeater , so that when the repeater impaired in the device or on the supply , the clerk did not know in person and just waiting for a report from the repeater keeper at any time at the shelter is not a repeater . There needs to be a device that can monitor the state of the repeater , which if detected interference at the source , supply and radio , PPE JTY officer may direct monitoring , so that it can assist in the handling and analysis of causes of hearing disorders without having to come to the site . GPRS Modem Utilization Intek J65i - X allows retrieval status of the repeater equipment where it can not be done at this time . With facilities tapped digital inputs and digital outputs on the modem , any condition of equipments such as radio signal repeater RX , TX radio signal , battery , charger and 220V supply state of the supply voltage can be detected . From changes in the supply voltage available , can be detected by a GPRS modem Intek J65i - X so that when there is an interruption in the HMI SCADA can termonitoring in real time . With the monitoring and control of a radio repeater communications , personnel no longer need to go to the location (site ) only to find the cause of the disturbance . Interference analysis can also be performed before treatment is held further disruption . Reset control radio can also be done quickly if the radio have to hang in its operation , so that the future will be able to improve the performance of SCADA systems PT PLN ( Persero ) APD Central Java and DI Yogyakarta. Keywords : repeater , modem GPRS Intek J65i - X , auxiliary relays , monitoring and control , HMI SCADA

New Trends of Transmission Capacity Evaluation of Submarine Fiber Cable systems with Different Ultra-High Multiplexing, Amplification and Propagation Techniques

This paper has presented the new trends of the performance evaluation of submarine fiber cable system with different ultra-high multiplexing and propagation techniques over a wide range of the affecting parameters. We have taken into account the ultimate optical transmission of 10,000 channels huge submarine cables under different depth conditions. Two amplification techniques are considered (the engagement of Raman and Erbium-doped fiber amplifiers). The double impact of both temperature and pressure is investigated through the defined depth penalty. Three transmission time division multiplexing techniques are studied, namely soliton, nonlinear and maximum time division multiplexing. Also, two multiplexing methods are considered in the design of ultra-wide wavelength division multiplexing (UW-WDM) (10,000 optical channels) and ultra-wide space division multiplexing UW-SDM (400 fiber links). Based on experimental data, both the deep ocean water temperature and pressure are tailored as functions of the water depth. The product of the transmitted bit rate and the repeater spacing is processed over wide ranges of the affecting parameters, where both the repeater spacing and the transmitted soliton bit rate are in positive correlations with the total number of links.

Maximization of repeater spacing in ultrawide-wavelength-division multiplexing optical communication systems based on multipumped laser diodes

We show that the amplifier bandwidth can be further increased and the gain spectrum can be tailored if one uses pumping with multiple laser wavelengths. We consider the wide-gain amplifier where four sets of multipumps are employed. We process two multiplexing techniques in long haul transmission cables where the number of channels is up to 9600 in ultrawide-wavelength-division multiplexing (UWWDM) with employment of the ultrawide-space-division multiplexing (UW-SDM) technique to merge the number of links up to 400 in the optical-fiber core over wide ranges of affecting sets of parameters. As well as the repeater spacing using a multi-pumping Raman amplifier, we investigate N R pumps in the optical pumping wavelength (from 1.36 to 1.44 μm) to amplify optical channels where the optical wavelength range (1.45–1.65 μm) satisfies near infrared optical transmission region.

Nonlinear Tolerant Spectrally-Efficient Transmission Using PDM 64-QAM Single Carrier FDM With Digital Pilot-Tone

We propose nonlinear tolerant single carrier frequency-division-multiplexing (SC-FDM) signal enhanced by digital pilot-tone for future high speed Ethernet transport like 400 G Ethernet. First, we discuss system configuration and the wavelength-division-multiplexed (WDM) transmission of SC-FDM signals employing polarization-division-multiplexed (PDM) 64-ary quadrature amplitude modulation (64-QAM). Next, we describe the long-haul transmission characteristics of 50 GHz-spaced 538 Gb/s × 7 ch WDM signals. We compare digital back-propagation (DBP) and digital pilot-tone for nonlinearity compensation and experimentally show that digital pilot-tone can effectively compensate the phase noise induced by inter-channel nonlinear effects with less computational complexity than DBP. Then we discuss a high-capacity transmission experiment employing 548 Gb/s PDM-64QAM SC-FDM; 102.3 Tb/s (224 × 548 Gb/s) C- and extended L-band WDM transmission is demonstrated over 240 km (3 × 80 km) of pure-silica-core fiber (PSCF) with all-Raman amplification. Thanks to the high nonlinear tolerance enhanced by pilot-tone, we can employ the 80 km repeater spacing used in conventional terrestrial systems. Assuming 20% forward error correction (FEC) overhead, a spectral efficiency of 9.1 b/s/Hz is achieved.

Hybrid quantum repeater with encoding

We present an encoded hybrid quantum repeater scheme using qubit-repetition and Calderbank-Shor-Steane codes. For the case of repetition codes, we propose an explicit implementation of the quantum error-correction protocol. Moreover, we analyze the entangled-pair distribution rate for the hybrid quantum repeater with encoding and we clearly identify a triple trade-off between the efficiency of the codes, the memory decoherence time, and the local gate errors. Finally, we show that in the presence of reasonable imperfections our system can achieve rates of roughly 24 Hz per memory for 20 km repeater spacing, a final distance of 1280 km, and a final fidelity of about 0.95.

Ultra High Transmission Capacity of Undersea Optical Fiber Cables for Upgrading UW-WDM Submarine Systems

This paper has proposed ultimate optical transmission of ultra multi transmission channels huge submarine cables has been investigated under different depth conditions. Conventional forward Raman amplification technique is con- sidered taking into account the reduction of the four wave mixing (FWM). The double impact of both ambient temperature and pressure effects are also investigated. The transmission technique is studied namely Soliton propagation technique. As well as two multiplexing methods are considered in the design namely ultra wide wavelength division multiplexing (UW-WDM) and ultra-wide space division multiplexing (UW-SDM). Based on experimental data, both the deep ocean water temperature and pressure are tailored as functions of the water depth. The product of the transmitted bit rate and the repeater spacing is processed over wide ranges of the affecting parameters.

Digital Compensation of Intercarrier Nonlinear Distortion With Carrier Phase Locking

Compensating for intercarrier nonlinear distortion allows launching higher power into the transmission fiber and it leads to an increase in the transmission distance. Numerical calculations show that the launch power is increased by 10 dB and the maximum transmission distance is more than tripled, when the optical repeater spacing of 80 km, dispersion-shifted fiber, and signal format of 10 Gb/s nonreturn-to-zero are assumed. It is experimentally demonstrated that waveform distortion due to the four-wave mixing (FWM) among different carriers in wavelength-division multiplexing (WDM) becomes deterministic by phase-locking optical carriers and that FWM distortion can be compensated at 5 Gb/s with three-channel condition by employing DSP at the transmitter or receiver.

On Ultimate Optical (10000 Channels) Transmission in Submarine Cables under Different Depth Conditions (Rigorous Analysis)

Ultimate optical transmission of 10000 channels huge submarine cables has been investigated under different depth conditions. Two amplification techniques are considered (the engagement of Raman and Erbium-doped fiber amplifiers). The double impact of both temperature and pressure is investigated through the defined depth penalty. Three transmission times division multiplexing techniques are studied namely soliton, nonlinear and maximum time division multiplexing. Also, two multiplexing methods are considered in the design of ultra-wide wavelength division multiplexing (UW-WDM) (10,000 optical channels) and ultra-wide space division multiplexing UW-SDM (400 fiber links). Based on experimental data, both the deep ocean water temperature and pressure are tailored as functions of the water depth. The product of the transmitted bit rate and the repeater spacing is processed over wide ranges of the affecting parameters, where both the repeater spacing and the transmitted soliton bit rate are in positive correlations with the total number of links.

Quantum repeaters using coherent-state communication

We investigate quantum repeater protocols based upon atomic qubit-entanglement distribution through optical coherent-state communication. Various measurement schemes for an optical mode entangled with two spatially separated atomic qubits are considered in order to nonlocally prepare conditional two-qubit entangled states. In particular, generalized measurements for unambiguous state discrimination enable one to completely eliminate spin-flip errors in the resulting qubit states, as they would occur in a homodyne-based scheme due to the finite overlap of the optical states in phase space. As a result, by using weaker coherent states, high initial fidelities can still be achieved for larger repeater spacing, at the expense of lower entanglement generation rates. In this regime, the coherent-state-based protocols start resembling single-photon-based repeater schemes.

Rigorous Analysis for Maximizing of Repeater Spacing using Multi-Pumping Raman Amplifier of Wide Gain

Rigorous Analysis for Maximizing of Repeater Spacing using Multi-Pumping Raman Amplifier of Wide Gain

British Telecom 565 Mbit/s lightline system

British Telecom is currently developing a 565 Mbit/s trunk optical fibre system which incorporates both multiplexing and line transmission. The system will operate at 1.3 µm over single-mode fibre with a 30 km repeater spacing. Extensive use is being made of ECL uncommitted logic arrays (ULAs) manufactured at British Telecom Research Laboratories (BTRL) and derived from the reliable ECL 40 process as used in submarine cable system integrated circuits. Details of the system design are presented together with the initial results of a laboratory system built out of commercially available components to establish confidence in the design.

NET EFFECTIVE GAIN OF MULTI-PUMPING RAMAN AMPLIFIER IN ULTRA-WAVELENGTH DIVISION MULTIPLEXING AND ULTRA-LONG – HAUL OPTICAL COMMUNICATION SYSTEMS

In the present paper, a net effective gain of multi -pumping Raman amplifier in ultra-wavelength division multiplexin g (UW-WDM) and ultra long-haul (ULH) optical communication systems has been modeled and parametrically investigated over wide ranges of affecting parameters, taking into account the polarization effect. NR pum ps are processed with or without equal spectral spacing. The effective fi ber core area, the gain coefficients and the amplified spontaneous emission power ASE (as a measure of the minimum detectable power) are calcul ated over the operating wavelength. The above three quantities ar e cast in simple polynomial forms. The average net Raman gain, the o n-off Raman gain, the signal-to-noise ratio at the effective length has been investigated also. The obtained results are employed to find the avera ge repeater spacing over the spectral range under the processing. It is concluded that for repeater spacing, the total injected Raman powers athe vital factor rather than the number of amplifiers, while for the gain spectral width, the number of amplifiers is the vital factor. The centr al wavelength of the subset of channels that propagates in a link indica tes the order of link. The total number of links in the core determines th e ultimate values of different effects.

A highly integrated 565 optical fibre system

This paper describes a 565 Mbit/s optical fibre system, developed by British Telecom Research Laboratories in association with Fulcrum Communications Ltd, which incorporates advanced integrated circuit (IC) technology and offers repeater spacings in excess of 40 km. An outline of the IC architecture and system design is presented together with the thermal management techniques adopted. Finally, a description is given of the results of a field trial of the system over a 77 km route between Birmingham and Derby.

WDM channels over 2000 km of standard singlemode fibre

2.5 Tbit/s transmission of 12.5 GHz-spaced 256 ultra-dense wavelength-division-multiplexing (WDM) channels over a standard singlemode fibre of 2000 km with a repeater spacing of 100 km is presented. A non-return-to-zero modulation format and C-band erbium-doped fibre amplifiers are exclusively used. The results demonstrate the upgradability of conventional WDM transmission networks towards UD-WDM transmission networks.