Coherent lightwave transmission at 2 Gbit/s over 170 km of optical fibre using phase modulation

We report coherent lightwave transmission at a data rate of 2Gbit/s over 170 km of optical fibre. Phase modulation is employed, and a bit error rate lower than 10-9 is achieved. The receiver sensitivity of ?39.0 dBm 10-9 BER) is an improvement of 2.4 dB over the best previously published direct-detection result for non-return-to-zero transmission.     

Polarisation-independent 20 Gbit/s soliton data transmission over12500 km using amplitude and phase modulation soliton transmissioncontrol

Polarisation-independent error-free 20 Gbit/s soliton data transmission over 12500 km with flat system Q dependence on distance, has been demonstrated using static filtering and a semiconductor polarisation-independent amplitude and phase modulator for soliton transmission control     

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.<>     

Bipolar optical FSK transmission experiments at 150 Mbit/s and 1Gbit/s

Bipolar direct modulation has been used to overcome the nonuniform low-frequency modulation response of distributed-feedback laser transmitter in optical FSK transmission experiments at 150 Mb/s and 1 Gb/s. The heterodyne receiver sensitivity was -48 dBm for 150 Mb/s and -39 dBm for Gb/s, independently of the pseudorandom pattern length. There was no degradation in receiver sensitivity with transmission through more than 100 km of fiber     

Dispersion-supported transmission at 20 Gbit/s over 53 km standardsinglemode fibre

The optical transmission of 20 Gbit/s signals over a record distance of 53 km standard nondispersion-shifted singlemode fibre (SMF) without optical dispersion compensation has been demonstrated successfully using a directly modulated MQW DFB laser operating at 1544 nm     

Error-free soliton transmission at 20 Gbit/s over 7150 km throughall-optical synchronous phase modulation

All-optical soliton synchronous phase modulation through transmission fibre is shown to enable error-free propagation of 20 Gbit/s signals up to 7150 km without the need for dispersion management. Tolerance to imperfect clock-signal synchronisation is characterised experimentally     

40 Gbit/s straight-line RZ data transmission over 240 km ofstandard fibre

The authors report straight-line single-channel 40 Gbit/s RZ data transmission over 240 km of standard fibre with periodic dispersion compensation. To the authors' knowledge, this is the longest transmission distance reported in a straight-line transmission experiment, at 40 Gbit/s without any precoding. The back-to-back receiver sensitivity of the system was 18.9 dBm for a BER of 10^-9 . Transmitting data over 240 km of fibre induced a sensitivity penalty of 0.4 dB for a BER of 10^-9     

120 km lightwave transmission experiment at 1 Gbit/s using a new long-wavelength avalanche photodetector

A transmission experiment was performed to study the high-speed potential of a long-distance gigabit lightwave system employing a single-frequency 1.5 ?m laser and a new long wavelength III?V avalanche photodetector. A 120 km length of standard production single mode fibre was used in the test, in which a bit error rate of 2×10?10 was achieved at 1 Gbit/s. This distance is the longest reported to date for rates higher than 500 Mbit/s, and the product of bit rate and distance (120 km Gbit/s) is the highest value achieved for any bit rate. The distance was limited by the 32.3 dB loss of the transmission path together with a total of 5.6 dB in power penalties associated with chirp broadening of the laser line.     

Optical self-homodyne DPSK transmission at 1 and 2 Gbit/s over 86 km of fibre

Optical self-homodyne DPSK transmission has been achieved at 1 and 2 Gbit/s data rates with respective receiver sensitivities of ?34.4 dBm and ?32.4 dBm at 10?9 BER. No dispersion penalty was observed after transmission through 86 km of optical fibre with 17 ps/?m/km dispersion at the operating wavelength of 1.53 ?m.     

8 Gbit/s transmission over 30 km of optical fibre

We demonstrate, for the first time, 8 Gbit/s digital transmission over single-mode optical fibre. A 30 km link was achieved using a directly modulated 1.31 ?m multilongitudinal-mode laser and an avalanche photodiode receiver.     

150km optical fibre transmission network experiment with 2Gbit/s throughput

Optical time-division multiplexing is considered for synchronous gigabit/s long-distance ransmission networks. Experimental results are presented for a 150 km fibre network of 2 Gbit/s capacity. The problem of differential fibre propagation delay variations is addressed with signal processing developed for the implementation of closed-loop feedback control.     

160 Gbit/s soliton data transmission over 200 km

Polarisation- and time-domain-multiplexed 160 Gbit/s soliton signals have been successfully transmitted over 200 km for the first time. The soliton source was a 10 GHz regeneratively modelocked fibre laser and a planar lightwave circuit was used for optical multiplexing. The soliton pulse width was ~1.5 ps. A polariser and a nonlinear loop mirror were used for demultiplexing from 160 to 10 Gbit/s     

40 Gbit/s transmission over 202 km of standard fibre using midspanspectral inversion

The authors demonstrate for the first time the transmission of a 4×10 Gbit/s OTDM data sequence over two unrepeatered links of 100 km of nondispersion shifted fibre. The experiment is enabled using midspan spectral inversion and electroabsorption modulator sources and demultiplexers, and results in a record bit-rate-distance product of 8.1 Tbit/s km for a single channel over standard fibre     

21.4 Gbit/s transmission over 200 km multimode fibre using coherent optical OFDM

Multimode fibre (MMF) has been deployed for local area networks and for optical interconnects. MMF has long been perceived as the medium for short reach systems, although it can achieve very high capacity [1]. In fact, the longest transmission distance for a channel rate of 10 Gbit/s and beyond is 11 km, requiring feedback from the receiver to the transmitter [2], and 5 km without receiver feedback [3]. Nevertheless it is instructive to note three important advantages that MMF possesses over single-mode fibre (SMF). First, MMF has proven ease of installation, maintenance and handling, which in turn leads to cost reduction. Secondly, MMF has much larger core area than SMF, which translates into much greater nonlinearity tolerance over SMF. Thirdly, from the information theoretical point of view, because of the existence of many modes in MMF, it can provide much higher information capacity than SMF via multiple-input multiple- out (MIMO) signal processing [4, 5]. Therefore a natural and fundamental question should be asked: is the multimode fibre fit for highspeed (.10 Gbit/s) and high-capacity communication system beyond short reach (.100 km)? The aforementioned third point becomes more relevant as recent research has shown rapid progress in the channel speed, whereas the improvement of overall capacity seems to be stalled. A sense of spectral efficiency bottleneck is looming large in the optical communication community.     

2.488 Gbit/s transmission experiment at 1550 nm over 153 km standard single-mode fibre

The transmission experiments demonstrate that operation of 2.488 Gbit/s optical transmission systems over more than 150 km standard SMF is not dispersion limited using today's 1550 nm DFB-lasers. With an extinction ratio as low as 11 dB a dispersion and extinction ratio penalty of less than 0.7 dB was observed.<>     

400 Mbit/s, 372 km coherent transmission experiment using in-lineoptical amplifiers

Reports on an optical transmission experiment using four in-line optical amplifiers. With a net gain of 58000 (47.7 dB) from the amplifiers, the authors were able to increase the longest nonregenerated transmission distance to 372 km. The system penalty associated with the amplifiers was only 1.5 dB     

Loss-limited transmission at 140 Mbit/s over 30 km of single-mode fibre using a 1.3 ?m LED

Using an edge-emitting LED source, 140 Mbit/s was transmitted over 30 km of single-mode fibre. No penalty in receiver sensitivity due to chromatic dispersion was observed. The product of data rate and distance, 4.2 Gbit/skm, is the highest reported for loss-limited transmission over single-mode fibre using an LED source.     

1 Gbit/s optical FSK heterodyne transmission experiment over 100 km of single-mode fibre

A 1 Gbit/s optical FSK modulation/heterodyne detection transmission experiment has been conducted at a wavelength of 1497 nm. The receiver sensitivity is ?37dBm and no degradation is observed after transmission through 100 km of single-mode fibre.     

10 Gbit/s, 1200 km error-free soliton data transmission using erbium-doped fibre amplifiers

Soliton data signals at 10 Gbit/s have been successfully transmitted for the first time through a 1200 km dispersion-shifted fibre by using 24 erbium-doped fibre amplifiers. A bit error rate below 10/sup -13/ was obtained with 2/sup 20/-1 pseudorandom patterns.<>     

400 Mbit/s transmission test using A 1.53 ?m DFB laser diode and 104 km single-mode fibre

Transmission characteristics for a 400 Mbit/s signal over a 104 km single-mode fibre are reported. A DFB laser diode is restricted to a single longitudinal mode at 1.53 ?m. No degradation is observed in the error-rate performance at a low loss and a finite dispersion wavelength.