Large Effective Area Fiber Research Articles

High-resolution DPP-BOTDA over 50 km LEAF using return-to-zero coded pulses

Coded optical probe pulses in return-to-zero/non-return-to-zero (RZ/NRZ) formats are used for long-range distance sensing based on a differential pulse-width pair Brillouin optical time-domain analysis (DPP-BOTDA) in order to enhance the spatial resolution and measurement accuracy. It is found that using the RZ format maintains the Brillouin spectral shape, enhances the sensing range and leads to a higher signal-to-noise ratio compared to a single-pulse Brillouin optical time-domain analysis. With 512 bit RZ-coded pulse pairs of 60/55 ns for the DPP-BOTDA, a spatial resolution of approximately 0.5 m and a strain resolution of 12 microepsilon (which is equivalent to a 0.7 MHz Brillouin frequency shift) have been achieved over a 50 km large effective area fiber.

Ultra-High-Capacity DWDM transmission system for 100G and beyond

We review and summarize several 100G per channel high-capacity transmission systems enabled by advanced technologies such as multilevel modulation format, new low-loss and large effective area fiber, hybrid EDFA/Raman amplification, and digital coherent detection technologies. We show that high-speed QPSK, 8PSK, 8QAM, and 16QAM can all be generated using commercially available optical modulators using only binary electrical drive signals through novel synthesis methods, and that all of these modulation formats can be detected using digital coherent detection. We also show our latest research results on 400 Gb/s and 1 Tb/s per channel by using orthogonal DWDM transmission technologies.

Transmission 32 × 10 Gb/s using LEAF and RDF in C band and L band for DWDM dispersion compensation

AbstractWe propose the experiment transport of 32 channels 10 Gbit/s dense wavelength division multiplexing (DWDM) system which uses large effective area fiber (LEAF) in combination with reverse dispersion fiber (RDF), which is a dispersion compensation device, in C and L band wavelength range to solve the dispersion program. The system structure transmission length of 800‐km consisted of 75‐km LEAF and 5‐km RDF for ten fiber spans. Q factor should be greater than 6 dB for good performance, corresponding to a bit error rate (BER) of less than 10−9, and all 32 channels have been measured for both Q factor and BER. The proposed system is applicable for ultra long‐haul transmission in DWDM systems. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2489–2492, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24667

A hybrid radio-on-DWDM transport system for PHS/LAN/ITS/WiMAX applications

A hybrid radio-on-dense-wavelength-division-multiplexing (DWDM) transport system for personal handy system (PHS)/local area network (LAN)/intelligent transport system (ITS)/worldwide interoperability for microwave access (WiMAX) applications was proposed and demonstrated. Improved performance of bit error rate (BER) over a 100 km of large effective area fiber (LEAF) was obtained. Signal qualities meet the PHS demand with a data signal of 1.9 GHz / 10 Mbps , LAN demand with a data signal of 2.4 GHz / 11 Mbps , ITS demand with a data signal of 5.8 GHz / 20 Mbps , and WiMAX demand with a data signal of 10 GHz / 70 Mbps .

Radio-on-DWDM Transport Systems Based on Injection-Locked Fabry-Perot Laser Diodes

A radio-on-dense-wavelength-division-multiplexing (DWDM) transport system based on injection-locked Fabry-Perot laser diodes (FP LDs) with four microwave carriers and large effective area fiber (LEAF) transmission was proposed and demonstrated. Good performance of bit error rate (BER) and intermodulation distortion to carrier ratio (IMD/C) over a-50km of LEAF was obtained. Signal quality meets the demands of personal handy system (PHS)/vehicle information and communication system (VICS)/electronic toll collection (ETC)/satellite broadcasting (SB).

Transmission Performance Comparison between Dispersion Compensation Fiber and Reverse Dispersion Fiber in High Rate DWDM Dispersion Compensation Frame

We propose and demonstrate the experiment transport of 8 channels 20 Gbit/s dense wavelength division multiplexing (DWDM) system structure that consists of Erbium doped fiber amplifier (EDFA) and large effective area fiber (LEAF) as a positive dispersion fiber. Negative dispersion compensation fiber employing dispersion compensation fiber (DCF) and reverse dispersion fiber (RDF) measure the transmission length and system performance. The proposed 8 channels 20 Gbit/s DWDM system structure is in L band wavelength range. L band wavelength range is between 1570.42 nm∼1576.02 nm, channel spacing 100 GHz. Dispersion compensation fiber (DCF) and reverse dispersion fiber (RDF) both have good performance of high rate in DWDM dispersion compensation frame. Good performance of Q factor should be greater than 6 dB, corresponding to a bit error rate (BER) of less than 10 -9 , and it has been measured for all eight channels [1]. This proposed system is suitable for the application in the long distance transmission communication and ultra-long haul (ULH) networks systems.

Radio over dwdm transport systems for PHS/VICS/ETC/SB applications FBG

A radio over dense-wavelength-division-multiplexing (DWDM) transport system for personal handy system (PHS)/vehicle information and communication system (VICS)/electronic toll collection (ETC)/satellite broadcasting (SB) applications was proposed and demonstrated. Improved performance of bit error rate (BER) over a-100 km of large effective area fiber (LEAF) was obtained. Signal qualities meet the PHS demand with a data signal of 1.9 GHz/10 Mbps, VICS demand with a data signal of 2.5 GHz/12 Mbps, ETC demand with a data signal of 5.8 GHz/20 Mbps, and SB demand with a data signal of 12 GHz/25 Mbps.

Transmission of 8 DWDM Channels at 20 Gbit/s over 680 km using Large Effective Area Fiber as well as Reverse Dispersion Fiber

Article Transmission of 8 DWDM Channels at 20 Gbit/s over 680 km using Large Effective Area Fiber as well as Reverse Dispersion Fiber was published on September 1, 2007 in the journal Journal of Optical Communications (volume 28, issue 3).

1000 cascaded stages of optical 3R regeneration with SOA-MZI-based clock enhancement to achieve 10-gb/s 125 000-km dispersion uncompensated transmission

We propose an optical 3R regenerator that incorporates a clock enhancement stage based on a semiconductor optical amplifier (SOA)-based Mach-Zehnder interferometer and a 10-GHz all-optical clock recovery module employing a Fabry-Perot filter and an SOA. The experiments assess the optical 3R regeneration technique using a fiber recirculation loop containing 125-km dispersion uncompensated large effective area fiber with a total chromatic dispersion of 531.25 ps/nm. The optical 3R regeneration achieves error-free 125 000-km dispersion uncompensated return-to-zero transmission at 10 Gb/s over 1000 optical 3R stages. The bit-error-rate (BER) measurements show that there is only 1.2-dB power penalty at 10-9 BER between 125 000-km (Lap 1000) uncompensated transmission and back-to-back using pseudorandom bit sequence 223-1

Dual-stage soliton compression of a self-started additive pulse mode-locked erbium-doped fiber laser for 48 fs pulse generation

A dual-stage single-mode fiber (SMF) and large-effective-area fiber (LEAF) link for generating 48 fs pedestal-free pulses from a 40 MHz self-started additive pulse mode-locked erbium-doped fiber laser (APM-EDFL) with output peak power and pulse energy of 16 kW and 500 pJ, respectively, is demonstrated. With the SMF+LEAF link, a maximum pulse-width compression ratio of 7 and an optimized pulse-energy confining ratio of up to 85% can be achieved, and the soliton self-frequency shift effect of the APM-EDFL pulse can be greatly suppressed.

Transmission improvement of DWDM systems under VCSELs with injection-locked technique and LEAF transport

A 10-Gb/s dense wavelength-division-multiplexing (DWDM) transport system based on vertical-cavity surface-emitting lasers injection-locked technique and large effective area fiber (LEAF) transport is proposed and demonstrated. Improved bit-error-rate performance was observed over a 60-km LEAF transport, attributed to the laser frequency chirp and chromatic dispersion reductions. This demonstrated that such a DWDM transport system is very attractive for the 10-Gb/s backbone applications, which can interoperate with high-speed optical communication networks.

A 10 Gbps WDM transport system based on VCSELs to VCSELs injection locked technique and LEAF transport

A 10 Gbps wavelength-division-multiplexing (WDM) transport system based on vertical cavity surface emitting lasers (VCSELs) to VCSELs injection locked technique and large effective area fiber (LEAF) transport is proposed and demonstrated. Improved bit error rate (BER) performance was observed over a 50 km LEAF transport, attributed to the laser bandwidth enhancement and chromatic dispersion reduction. This demonstrated that such a WDM transport system is very attractive for the 10 Gbps backbone applications, which can inter-operate with high-speed optical communication networks.

A-10Gbit/s lightwave transport system based on VCSEL and SOA with external light injection technique

A-10Gbit/s lightwave transport system over a-50km large effective area fiber (LEAF) tranmission based on vertical cavity surface emitting laser (VCSEL) and semiconductor optical amplifier (SOA) with external light injection technique is proposed and demonstrated. Improved bit error rate (BER) performance was observed under direct modulation of 10Gbit/s, attributed to the LEAF to reduce the total fiber dispersion and SOA light injection technique to suppress the SOA-induced distortion. This demonstrated lightwave transport system is very attractive for the 10Gbit/s backbone applications, which can inter-operate with high-speed optical communication networks.

Dispersion-flattened designs of the large effective-area single-mode fibers with ring index profiles

Two kinds of the large effective-area fibers with the ring index profiles named RI and RII type were proposed. In view of the impossibility to deduce the expression of waveguide dispersion directly due to the complexity of the characteristic equations, a feasible approach to calculate waveguide dispersion was established successfully. The influences made by the geometric parameters and optical parameters on the waveguide dispersion and cutoff characteristics of low order modes were analyzed. The calculated results indicate that the dispersion-flattened and large effective-area performances can be achieved simultaneously by adjusting the geometric and optical parameters in a region of wavelengths. A dispersion-flattened fiber design with the total dispersion of about 4.5 ps/nm/km, dispersion slope of below 0.006 ps/nm 2/km and the effective areas from 95 to 118 μm 2 in the spectral range of 1540–1620 nm was presented and its tolerance analysis and bending loss characteristics at 1550 nm were also examined.

Transmission over 5.6 km large effective area and low-loss (1.7 dB/km) photonic crystal fibre

A 10 Gbit/s non-return-to-zero signal at 1550 nm over 5.6 km photonic crystal fibre (PCF) with 1.7 dB/km loss has been successfully transmitted, demonstrating the potential of PCF as transmission fibre. It is envisaged that photonic crystal fibres can be used in future optical communication systems not only as signal processing elements but also as the transmission medium.

A hybrid CATV/256-QAM/OC-48 DWDM system over an 80-km LEAF transport

A hybrid dense-wavelength-division-multiplexing (DWDM) system for CATV, 256-QAM and OC-48 trunking is proposed and demonstrated. It used two wavelengths for AM-VSB CATV, one wavelength for 256-QAM digital passband signals and four wavelengths for OC-48 (2.5 Gb/s) digital baseband signals transport. Good performances of carrier-to-noise ratio (CNR) /spl ges/ 50 dB, composite second order (CSO) /spl ges/ 67 dB and composite triple beat (CTB) /spl ges/ 65 dB were obtained for AM-VSB CATV; and low bit error rate (BER < 10/sup -9/) had been achieved for 256-QAM and OC-48 digital signals over an 80 km large effective area fiber (LEAF) transport.

Dispersion compensation and crosstalk reduction in a bidirectional dense wavelength division multiplexing cable television system

We propose and demonstrate a bidirectional dense wave- length division multiplexing cable television system that uses large effec- tive area fibers (LEAFs) as transmission fibers and chirped fiber grating (CFG) as a dispersion compensation device to reduce the dispersion and cross-phase modulation (XPM)-induced crosstalk. By comparing the system link with the transmission length of a 50-km single-mode fiber (SMF) without CFG, good performances of carrier-to-noise ratio (CNR) >50 dB, a composite second order (CSO) >69 dB, and a composite triple beat (CTB) >66 dB are obtained in our proposed system over a 50-km LEAF transport. © 2003 Society of Photo-Optical Instrumentation Engineers. (DOI: ORACLE)

Hybrid 10-Gb/s, 2.5-Gb/s, 64-QAM, and AM-VSB high-capacity wavelength-division-multiplexing transport systems using SMF and LEAF fibers

A four-wavelength high-capacity hybrid wavelength-division-multiplexing (WDM) system separately over 100-km standard single-mode fiber and nonzero dispersion-shifted fiber of large effective area fiber is demonstrated. The WDM wavelengths contain one 10-Gb/s signal, one 2.5-Gb/s signal, one 64-quadrature amplitude modulator signal of 110 channels, and one amplitude module with vestigial sideband signal of 80 channels. Satisfaction of a huge variety of receiving requirements and reduction of fiber nonlinearities-induced degradations by controlling channel powers are also considered. Such a hybrid WDM system would be attractive for multiservice trunk applications in advanced transport systems for providing both CATV and telecommunication services.

Penalty-free 10 Gbit/s single-channel co-pumped distributed Raman amplification using low RIN 14xx nm DFB pump

A penalty-free 10 Gbit/s single-channel transmission with co-pumped distributed Raman amplification using novel high power, low relative integrity noise (RIN), multimode 14xx nm distributed feedback pump is reported. No penalty from pump to signal RIN transfer was observed with co-pumped Raman gains up to 6 dB large effective area fibre (LEAF). In contrast, 0.5 dB penalty was observed with a fibre Bragg grating stabilised pump at 6 dB of Raman gain.

Bidirectional Transport of AM-VSB CATV System

We propose and demonstrate, for the first time, a bidirectional externally modulated NTSC AM-VSB 77-channel transport system over an 80-km large effective area fiber (LEAF) which used bidirectional transport and dense-wavelength-division-multiplexing (DWDM) techniques. By comparing with the system link with a transmission length of 80 km single-mode fiber (SMF) and truewave fiber (TWF), not only channel capacity was doubling, but also good carrier-to-noise ratio (CNR) > 50 dB, composite second order (CSO) > 68 dB and composite triple beat (CTB) ≥ 64 dB performances were obtained in our proposed system after an 80-km LEAF transport.