Spectral efficiency of coded phase modulation for high-speed fiber optic communication

2004 ◽  
Author(s):  
G. Kramer ◽  
A. van Wijngaarden ◽  
A. Ashikhmin ◽  
X. Wei
Keyword(s):  
Spectral Efficiency ◽  
Phase Modulation ◽  
High Speed ◽  
Fiber Optic ◽  
Fiber Optic Communication ◽  
Optic Communication

Tributary Mapping Multiplexing an Efficient Technique for High Speed Fiber Optic Communication

2018 ◽  
Vol 6 (2) ◽  
Author(s):  
Usman Illahi ◽  
Javed Iqbal ◽  
Muhammad Ismail Sulaiman ◽  
Muhammad Alam ◽  
Mazliham Mohd Su'ud
Keyword(s):  
Spectral Efficiency ◽  
High Speed ◽  
Fiber Optic ◽  
Single Channel ◽  
Efficient Technique ◽  
High Dispersion ◽  
Optical Filtering ◽  
Fiber Optic Communication ◽  
Optic Communication ◽  
Dispersion Tolerance

<p>A novel technique of multiplexing called Tributary Mapping Multiplexing (TMM) is<br />applied to a single channel wavelength division multiplexing system and performance is monitored on the basis of simulation results. To elaborate the performance of TMM in this paper, a 4-User TMM system over single wavelength channel is demonstrated. TMM showed significant tolerance against narrow optical filtering as compared to that of conventional TDM at the rate of 40 Gbit/s. The above calculations are made by optical filter bandwidth and dispersion tolerance that was allowed at minimum. The spectral efficiency achieved by this TMM was 1 b/s/Hz and it was executed by using transmitters and receivers of 10 Gbit/s without polarized multiplexing. The high spectral efficiency, high dispersion tolerance and tolerance against strong optical filtering makes TMM an efficient technique for High<br />Speed Fiber Optic Communication.</p>

scholarly journals Time Domain Equalization and Digital Back-Propagation Method-Based Receiver for Fiber Optic Communication Systems

2020 ◽  
Vol 2020 ◽  
pp. 1-13 ◽  
Author(s):  
Fazal Muhammad ◽  
Farman Ali ◽  
Usman Habib ◽  
Muhammad Usman ◽  
Imran Khan ◽  
...  
Keyword(s):  
Optical Fiber ◽  
Spectral Efficiency ◽  
Communication Systems ◽  
High Speed ◽  
Fiber Optic ◽  
Detection System ◽  
Data Rate ◽  
Modulation Formats ◽  
Fiber Optic Communication ◽  
Optic Communication

Fiber optic communication systems (FOCSs) have attained a lot of attention by revolutionizing the telecommunication industry and offering new possibilities with the technical advancements in state-of-the-art high speed digital electronics. Advanced modulation formats make use of the phase, amplitude, and polarization of the optical signals at the same time to provide high spectral efficiency as compared with 1 bit/s/Hz for the intensity modulation direct detection system (IMDD), but are highly prone to transmission impairments. Thus, the effects that add up to the optical fiber impairments such as optical fiber chromatic dispersion (OFCD), polarization model dispersion (PMD), and phase offset and noise (POaN) need to be addressed at the receiver side. The development of components and algorithms to minimize these effects in next generation FOCSs with 100 Gbps data rate and beyond with long-haul transmission is still a challenging issue. In this paper, digital signal processing- (DSP-) assisted dispersion and nonlinear compensation techniques are presented to compensate for physical layer impairments including OFCD, PMD, and POaN. The simulations are performed considering Dual Polarization- (DP-) QPSK modulation format to achieve two-fold data rate to achieve spectral efficiency of 3.28 bits/s/Hz by making use of the polarization diversity and system performance is investigated in terms of bit error rate (BER), constellation diagrams, and quality factor (Q-factor) for different values of optical signal-to-noise ratio (OSNR), launch power (PL), and fiber length.

Optical data signals in fiber optic communication links with fading

2019 ◽  
pp. 94-104
Author(s):  
I. Juwiler ◽  
I. Bronfman ◽  
N. Blaunstein
Keyword(s):  
Spectral Efficiency ◽  
Fiber Optic ◽  
Fiber Optic Cable ◽  
Optical Signals ◽  
Dispersion Properties ◽  
Optical Cable ◽  
Time Dispersion ◽  
Communication Links ◽  
Fiber Optic Communication ◽  
Optic Communication

Introduction: This article is based on the recent research work in the field of two subjects: signal data parameters in fiber optic communication links, and dispersive properties of optical signals caused by non-homogeneous material phenomena and multimode propagation of optical signals in such kinds of wired links.Purpose: Studying multimode dispersion by analyzing the propagation of guiding optical waves along a fiber optic cable with various refractive index profiles of the inner optical cable (core) relative to the outer cladding, as well as dispersion properties of a fiber optic cable due to inhomogeneous nature of the cladding along the cable, for two types of signal code sequences transmitted via the cable: return-to-zero and non-return-to-zero ones.Methods: Dispersion properties of multimode propagation inside a fiber optic cable are analyzed with an advanced 3D model of optical wave propagation in a given guiding structure. The effects of multimodal dispersion and material dispersion causing the optical signal delay spread along the cable were investigated analytically and numerically.Results: Time dispersion properties were obtained and graphically illustrated for two kinds of fiber optic structures with different refractive index profiles. The dispersion was caused by multimode (e.g. multi-ray) propagation and by the inhomogeneous nature of the material along the cable. Their effect on the capacity and spectral efficiency of a data signal stream passing through such a guiding optical structure is illustrated for arbitrary refractive indices of the inner (core) and outer (cladding) elements of the optical cable. A new methodology is introduced for finding and evaluating the effects of time dispersion of optical signals propagating in fiber optic structures of various kinds. An algorithm is proposed for estimating the spectral efficiency loss measured in bits per second per Hertz per each kilometer along the cable, for arbitrary presentation of the code signals in the data stream, non-return-to zero or return-to-zero ones. All practical tests are illustrated by MATLAB utility.

THE DESIGN AND FABRICATION OF HIGH-SPEED HBT CIRCUITS FOR FIBER-OPTIC COMMUNICATION SYSTEMS

1994 ◽  
Vol 05 (03) ◽  
pp. 253-274 ◽  
Author(s):  
MASAO OBARA ◽  
JUNKO AKAGI
Keyword(s):  
Measurement System ◽  
Communication Systems ◽  
High Speed ◽  
Fiber Optic ◽  
Heterojunction Bipolar Transistor ◽  
Fiber Amplifiers ◽  
Speed Measurement ◽  
Fiber Optic Communication ◽  
Optical Fiber Amplifiers ◽  
Optic Communication

AlGaAs/GaAs heterojunction bipolar transistor (HBT) high speed ICs have been paving the way for the most sophisticated fiber-optic communication systems since the late 1980s. Recently 20 Gbps HBT ICs have been developed to accommodate the emergence of optical fiber amplifiers. HBT technology is now proceeding towards the development of 40 Gbps systems where the lack of high speed measurement system remains an issue.

A Managerial Analysis of Fiber Optic Communications

2009 ◽  
pp. 866-872
Author(s):  
Mahesh S. Raisinghani ◽  
Hassan Ghanem
Keyword(s):  
Optical Fiber ◽  
High Speed ◽  
Fiber Optic ◽  
Single Bundle ◽  
Digital Subscriber Line ◽  
Last Mile ◽  
Fiber Optic Communication ◽  
Optic Communication ◽  
Voice Data ◽  
Roll Out

A form of fiber-optic communication delivery in which an optical fiber is run directly onto the customers’ premises is called Fiber to the Premises (FTTP). This contrasts with other fiber-optic communication delivery strategies such as Fiber to the Node (FTTN), Fiber to the Curb (FTTC), or Hybrid Fiber-Coaxial (HFC), all of which depend upon more traditional methods such as copper wires or coaxial cable for “last mile” delivery (Fiber to the Premises, 2007). While high-speed fiber-optic cables are more often used to provide the primary links, the “last mile” to each home still plays an important role in the quality of service and bringing high-speed broadband to an area that is largely dependent on this last-mile connection. FTTP involves laying optical fiber from a central location (switch) to a termination point (the home or business), and could potentially deliver broadband at speeds of up to 100Mbps. The actual speed is determined by the size of the Passive Optical Network (PON). The technology is capable of transmitting data at speeds of up to 2.5Gbps; this amount is divided by the number of termination points on the PON to determine the actual bandwidth to each end point. Replacing copper infrastructures with fiber to every home in an area is an expensive proposition, but the rewards could be great for telecom providers. An FTTP infrastructure would enable those providers to not only provide high-speed broadband; they could also expand into other areas such as cable programming. The Baby Bells have another incentive to roll out FTTP as well; the FCC requires them to share their copper wires with their competitors, but that requirement would not apply to new FTTP infrastructures. This ruling gives providers a major incentive to roll out FTTP, despite the large initial investment that is required. Copper, the predominant connection to the home used today, has inherent limitations both in terms of length from home to switch, and amount of bandwidth that is provided. FTTP also has a great advantage over Digital Subscriber Line (DSL), which provides broadband over existing copper, because DSL infrastructures must have more central relay points due to distance limitations. DSL is limited to only a few thousand feet between the switch and the home; FTTP allows for up to 49.6 miles (80 kilometers) between the home and the central switch. Cable broadband already has a head start, but FTTP offers some advantages, in that cable has a limited upstream bandwidth. FTTP, while still very new, holds great promise. It will enable providers to easily provide customers with a single bundle of services that comprise voice, data, and video. Ultimately, FTTP will deliver higher bandwidth to the home, and a wider range of services at an affordable price. While some FTTP projects focus on replacing existing copper cable, new “greenfield” areas such as new housing developments are likely to see FTTP from the very beginning (WiseGeek, 2007).

scholarly journals New high-speed system for controlling the parameters of a nuclear reactor in a nuclear power plant

2019 ◽  
Vol 140 ◽  
pp. 02001 ◽  
Author(s):  
Roman Davydov ◽  
Valery Antonov ◽  
Sergey Makeev ◽  
Yury Batov ◽  
Valentin Dudkin ◽  
...  
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Control Systems ◽  
High Speed ◽  
Nuclear Power ◽  
Nuclear Reactor ◽  
Fiber Optic ◽  
Fiber Optic Communication ◽  
Optic Communication ◽  
Communication Lines

The necessity of modernizing current control systems for functional units of a nuclear power plant, as well as the development of new control systems with a high degree of reliability and speed, is substantiated. The advantages of using optical sensors and fiber-optic communication lines to solve these problems are noted. Cases for which it is necessary to develop new fiber-optic sensors for monitoring parameters, for example, the flow of coolant or feed water, are considered. In some of them, it is more expedient to use standard designs of fiber-optic sensors to control the operating parameters of various blocks, for example, to control the electric field strength. A device and a control scheme for the parameters of the units and systems of a nuclear power plant using fiber-optic communication lines have been developed. The results of measuring various parameters of a nuclear reactor are presented. They showed that our proposed fiber-optic control and monitoring system for nuclear power plants operates more reliably and efficiently than systems with analogue control and measurement channels. The use of fiber-optic systems allows real-time remote control and high-speed control in terms of issuing commands to devices. This is very important when servicing a nuclear power plant while it is operating in extreme conditions.

Sign in / Sign up

Export Citation Format

Share Document