Wolfgang Pöhlmann

A 10 Gb/s eye opening monitor IC for decision-guided optimization of the frequency response of an optical receiver

The use of high bit rates for TDM transmissions on long haul fiber links is not only limited by the speed of electronic components but also by problems like fiber dispersion, polarization mode dispersion and fiber nonlinearities, especially if an installed standard fiber is used. An approach to alleviate these problems is the use of electronic signal-processing functions and advanced modulation schemes. This single chip eye opening monitor (EOM) is for use as part of such a signal processing unit. Apart from the data signal, a regenerated clock of arbitrary phase is needed to generate a dc output voltage proportional to the horizontal eye opening with a response time of <1 ms. The IC, in 50 GHz-f/sub T/ SiGe bipolar technology, covers bit rates from 2 to 12.5 Gb/s and dissipates 4.95 W from -5 V.

A silicon-bipolar amplifier for 10 Gbit/s with 45 dB gain

A 10 Gbit/s limiting main amplifier for use in optical transmission systems was implemented in an advanced 0.4 /spl mu/m silicon-bipolar technology. The device has one differential input and two differential outputs. It is mounted and bonded on a softboard carrier for all of the following measurements. The small signal differential gain is 45 dB and the bandwidth is 9 GHz. The output voltage is limited to 400 mV/sub pp/ differential at each output. The minimum input voltage for 1.10/sup -9/ bit error ratio at a pseudo random word of length 2/sup 23/-1 was measured to be 2.25 mV/sub pp/. The chip area is 1.8 mm/spl times/3.1 mm. The power dissipation is 400 mW at a single supply voltage of -4 V. >

40 Gbit/s quaternary dispersion supported transmission over 31 km standard singlemode fibre without optical dispersion compensation

Using electrical time division multiplexing and demultiplexing, 40 Gbit/s transmission over an uncompensated standard singlemode fibre link is reported for the first time. The system includes a decision circuit realised in SiGe HBT technology.

2.24-Gbit/s 151-km optical transmission system using high-speed integrated silicon circuits

Optical transmission experiments performed at 2.24 Gb/s using standard single-mode fiber with dispersion zero at 1.3 mu m are discussed. In the optical transmitter, a 1.5- mu m-wavelength distributed feedback laser is directly modulated by means of a special electrical drive pulse shaping technique. A link length of up to 151 km is bridged. This is the longest repeater distance at 2 Gb/s using direct detection without optical amplifiers reported so far. Moreover, the transmission system includes multiplexing and demultiplexing equipment using specially developed high-speed silicon integrated circuits. The whole system is assembled in a version suitable for field trial applications. >