Error-free 250 km transmission in standard fibre using compact 10 Gbit/s chirp-managed directly modulated lasers (CML) at 1550 nm

10 Gbit/s transmission over 250 km of standard fibre at 1550 nm with 4.8 dB penalty using a transmitter comprising a directly modulated DFB laser, a multi-cavity filter and a standard receiver, is demonstrated.     

800 Gbit/s (80×10.66 Gbit/s) transmission over 3200 km ofnon-zero dispersion shifted fibre with 100 km amplified spans employingdistributed Raman amplification

80×10.66 Gbit/s wavelength division multiplexing transmission over 3200 km fibre with 100 km amplifier spacing and 50 GHz channel spacing is demonstrated. Error-free transmission of all 80 channels is achieved by employing distributed Raman amplification, forward error correction and low dispersion slope TrueWave^R fibre     

Optical time-division multiplexed transmission at 8 Gbit/s using single laser and semiconductor optical power amplifier

The authors report transmission over 57 km of single-mode fibre in a two-channel, 8 Gbit/s optical time-division multiplexed system experiment using a transmitter with a single laser and a semiconductor optical power amplifier at the transmitter output. The amplifier operates with a net gain of 11.5 dB, which corresponds to 0.8 dB gain compression, and a fibre coupled output power of +6 dBm. The amplifier facet output power for which the gain is compressed by 3 dB is +13 dBm. The experimental system uses neither an isolator nor an optical filter.<>     

New data regeneration scheme for multi-Gbit/s fibre-optic links

A novel optical regeneration scheme without using nonlinear clock recovery elements has been demonstrated in a transmission experiment at 2.4 Gbit/s over 35 km of fibre. In this scheme, the clock is superimposed on the data signal at the transmitter end, and is separated from the composite signal by passive filters at the receiver end for data regeneration     

1 Tbit/s km transmission experiment at 16 Gbit/s using conventional fibre

Describes a single-channel optical transmission experiment that achieved a bit rate-distance product of 1 Tbit/s km over conventional (non-dispersion-shifted) fibre. The transmitter was a directly modulated, 1.3 mu m-wavelength, distributed feedback laser. The receiver employed a semiconductor optical preamplifier and a high-impedance pinHEMT front-end.<>     

Ultralow error rate and dispersion-free transmission of 2.5 Gbit/s SONET for gigabit networks

It is demonstrated that for an NRZ modulated 1310 nm optical transmitter, dispersion-free transmission can be achieved up to approximately 250 km using dispersion-shifted singlemode fibre (DS-SMF) and optical pulse compression. This result implies that DS-SMFs have a potential advantage over standard SMFs for dual-window (1310/1550 nm) multigigabit per second transmission systems. Results on the long-term error performance of experimental prototype 2.5 Gbit/s SONET optical transmission systems are presented with measured error rates smaller than 10/sup -15/.<>     

1.2 Gbit/s, 52.5 km optical fibre transmission experiment usingOEICs on GaAs-on-InP heterostructure

High-performance, long-wavelength OEICs on a GaAs-on-InP heterostructure were fabricated. For the transmitter OEIC, high-speed operation up to 2.4 Gbit/s was achieved, and a receiver sensitivity as high as -26.0 dBm for a 1.2 Gbit/s NRZ signal was realised for the receiver OEIC. To confirm the usefulness of these OEICs for optical fibre networks, a 1.2 Gbit/s optical fibre transmission experiment was successfully carried out over a 52.5 km span     

Comparison of direct and external modulation for CATV lightwave transmission at 1.5 mu m wavelength

The use of a high-power 1.5 mu m DFB laser and a linearised Ti:LiNbO/sub 3/ Mach-Zehnder modulator as a transmitter in a CATV lightwave system is reported. The performance is compared with directly-modulated 1.5 mu m-wavelength DFB lasers in 60 channel transmissions over 16 km of conventional singlemode fibre. The transmission of 52 high-frequency channels is demonstrated (450-750 MHz) in anticipation of future CATV upgrades.<>     

Wavelength-division-multiplexed optical transmission system with single-mode fibre and a dual-wavelength hybrid laser light source

Wavelength-division-multiplexed optical fibre transmission over a 45km single-mode fibre using a hybrid dual-wavelength InP CSBH laser light source emitting at 1.3 ?m and 1.5 ?m has been demonstrated. This simple and economic system provides two distinct optical data channels without requiring electronic or optical multiplexing. Optical crosstalk was unobservable while operating the separate optical channels at 1.5 Gbit/s and 90 Mbit/s, respectively. The use of a single light source eliminates multiple fibre-to-source alignments, reducing transmitter packaging costs.     

10 gigabit Ethernet long-haul transmission without in-line EDFAs

In this contribution, we present experimental results on optical packet transmission of two 10 gigabit ethernet channels (10Ge) over 252 km link of standard single mode fibre (Ssmf, itu-t Recommendation G.652) and 287 km long link composed of 85 km ofSsmf and 202 km of non-zero dispersion-shifted (Nz DSF, itu-t Recommendation G.655) without deployment of in-line erbium-doped fiber amplifiers (Edfas). All the active components, dispersion compensating fibre (Dcf) modules and optical band-pass filters were placed at the transmitter and at the receiver side of the link. To our best knowledge, this is the first report of pure Ethernet transmission without in-lineEdfas over such a distance. The results are encouraging especially for operators of national research and educational networks who rely on leased dark fibres and prefer as long transmission as possible without deployment of in-line amplifiers.     

5 Gbit/s, +10 dBm lossless transmission in 10 km distributed erbium fibre amplifier

The first data transmission over a distributed erbium-doped fibre amplifier is reported. A +10 dBm input signal, intensity modulated at 5 Gbit/s has been transmitted without loss or distortion over a 10 km fibre, pumped with a total of 50 mW pump power at 1485 nm.<>     

Adaptive quantised feedback equalisation for FSK heterodynetransmission at 150 Mbit/s and 1 Gbit/s

An adaptive quantised feedback equaliser has been used in an FSK heterodyne receiver to overcome the nonuniform frequency modulation response of a DFB laser transmitter in FSK transmission experiments at 150 Mbit/s and 1 Gbit/s with fibre spans of 121 km and 136 km, respectively     

2.5 Gbit/s, 10073 km straight line transmission system experiment using 199 Er-doped fibre amplifiers

A 2.5 Gbit/s, 50 km span straight line transmission over 10000 km using 199 Er-doped fibre amplifiers was successfully demonstrated. The simultaneous transmission of supervisory control and response signals was also confirmed.<>     

3.2 Tbit/s (80 × 40 Gbit/s) phase-shaped binary transmissionover 3 × 100 km with 0.8 bit/s/Hz efficiency

50 GHz-spaced 80 × 40 Gbit/s WDM transmission over 300 km of TeraLight^TM fibre is demonstrated without polarisation demultiplexing, using the PSBT format. A record capacity of 3.2 Tbit/s is thus achieved over the C-band only, with a spectral efficiency of 0.8 bit/s/Hz     

New type of optical fibre analogue SSB data communication system using edge‐emitting LED coupled to single‐mode optical fibre

This paper describes a single‐mode(SM) optical fibre SSB data communication system for use in place of power‐line data transmission. In the optical transmitter, SSB data is fed through the squarewave frequency (SWFM) modulator to the edge‐emitting LED (ELED) module. The light beam of the ELED module is fed to the SM optical fibre having a length of 12km. In the optical receiver, the light beam received through the SM optical fibre is detected by the PIN photodiode module, and fed to the SWFM detector to obtain the double‐pulse frequency modulation (DPFM) signal voltage. The DPFM signal voltage at the output of the SWFM detector is fed to the low‐pass filter (LPF) to obtain analogue SSB data. When the transmission was experimentally carried out, the spurious component was as low as −50–−70 dB and the SNR of SSB data as high as more than 65–70 dB. The optical transmitter and receiver were attached to the conventional analogue SSB data communication system to constitute a new optical fibre analogue SSB data communication system. During the field test utilizing the new system, the crosstalk and SNR were 60–70 dB and 60–70 dB on each channel, respectively. Copyright © 1999 John Wiley & Sons, Ltd.     

1 Gbit/s bipolar optical FSK transmission experiment over 121 km offibre

Bipolar direct modulation has been used to overcome the nonuniform low-frequency modulation response of a DFB laser transmitter in a 1 Gbit/s optical FSK transmission system. The heterodyne receiver sensitivity (nP¯) was -39 dBm for a 2²³-1 bit pseudorandom pattern, with no degradation in receiver sensitivity after transmission through 121 km of fibre     

Ultra-low-loss (0.1484 dB/km) pure silica core fibre and extensionof transmission distance

A pure silica core fibre with unprecedented low-loss of 0.1484 dB/km has been successfully fabricated. With a large effective area of 118 μm², this ultra-low-loss fibre extends transmission distance by 33% compared to conventional Ge-SMF, and over 400 km distance transmission is possible with Raman amplification     

Soliton transmission over more than 90 km using distributederbium-doped fibres

The transmission of 11.5 ps solitons over 93.4 km of distributed erbium-doped fibre is reported. By inserting a 29.3 km long midsection singlemode fibre instead of 32.5 km of erbium-doped fibre, the signal excursions are lowered, and 9.0 ps solitons are transmitted over 90.2 km     

1.6 Tbit/s (40 × 42.7 Gbit/s) WDM transmission over 2400 kmof fibre with 100 km dispersion-managed spans

Transmission of 40 × 42.7 Gbit/s WDM channels is demonstrated over 2400 km of fibre with 100 km amplifier spacing and 100 GHz channel spacing. Dispersion-managed fibre spans, carrier-suppressed return-to-zero modulation format and hybrid Raman/erbium-doped fibre inline amplifiers were employed to achieve a record 40 Gbit/s, WDM transmission distance with 100 km terrestrial span lengths     

Gbit/s transmission experiments with a 1.3 ?m high-speed surface-emitting LED and multimode graded-index fibre

Using a 1.3 ?m wide-bandwidth surface-emitting LED, transmission experiments were performed with 50/125 ?m multimode, graded-index fibre. Pulse shaping and equalisation were used in achieving a 10-9 bit-error rate at 1.0 Gbit/s over 3.0 km with a system margin of 1.1 dB. At 500 Mbit/s the margin increased to 7.0 dB. The 3.0 Gbit km/s data rate-distance product represents a new level of performance for a surface-emitting LED and multimode fibre.