Jan Codenie

Comparison of a bipolar and a CMOS front end in broadband optical transimpedance amplifiers

In this paper, first a new configuration for a preamplifier circuit used in broadband optical communication networks is presented. Secondly this differential transimpedance amplifier has been implemented in both a bipolar and a CMOS process. Simple formulas for the main characteristics are derived for both implementations. Measurements show the good performance of the configuration used, and highlight the differences between both implementations.

Implementation of a digital amplitude detector based on the Cordic transform

A digital implementation of an amplitude detector for Automatic Gain Control in a complex modulation format receiver is presented. The algorithm is based on the Co-Ordinate Rotation Digital Computer method which makes the amplitude detection very fast and accurate. The efficient topology enables realisation in a standard programmable gate array. Measurements on a 16QAM burst mode receiver are presented.

Performance of Burst-mode Receiver and Optical Repeater Units in SuperPON.

This paper describes the TDMA uplink of the ACTS PLANET project, realizing a high split long range access network using optical amplification. An overview of the network topology and the different building blocks is given. In particular, the differentiating burst mode receiver, the optical repeater units and the amplified splitter controller will be discussed. Bit error measurements were performed to define the system limits of the access network. It is shown that a feeder length of 90 km, in combination with a split factor of 2000 and a drop section length of 10 km are feasible.

Control of upstream optical repeaters for SuperPON access networks

This paper reports on the control systems for upstream optical repeaters in a long range high-split ratio SuperPON access network. Optical amplification means of fast switching semiconductor optical amplifiers is used. Two methods to control the drive current of the optical amplifiers are described: a feed forward self-triggered scheme and a topology using a priori known talker identity information. Trade-offs between both systems will be discussed. The first alternative was used in a lab demonstrator set-up, while the second will be used in a small field trial.

A lab demonstration of a SuperPON optical access network

This paper contains experimental results obtained from the ACTS PLANET (Photonic Local Access NETwork) Lab demonstrator, which confirm the technical feasibility of the SuperPON concept. The SuperPON is an optical fibre-based ATM access network which can support a large number of subscriber Optical Network Units (ONUs) up to 2048 and cover a long distance of 100 km.

16 QAM burst mode receiver for upstream communication over CATV networks

This paper discusses a 16 QAM burst mode receiver system for upstream communication over the CATV network. A prototype is realised in a hybrid analog-digital technology using standard programmable logic components. Efficient data transport is ensured by partially overlapping phase, amplitude and symbol timing recovery during a preamble with fixed content. Important technical issues and measurements are presented.

Fast synchronization algorithms of burst-mode 16 QAM receiver for video-on-demand applications

This paper describes a novel TDMA/FDMA combined 16 QAM receiver architecture developed for video-on-demand applications. A burst-operated rapid synchronization scheme is proposed which employs an efficient training preamble for overlapped operation of automatic gain control, carrier phase acquisition and symbol timing alignment. All the dedicated synchronization algorithms are digitally implemented, using field programmable gate arrays (FPGA), for a data rate of 10.8 Mbit/s. Several analytic relationships for control accuracy, acquisition time and signal to noise ratio (S/N) are derived. Experimental results demonstrate that the proposed method significantly decreases the required preamble length to 23 symbols, together with a dynamic range of 11 dB and a sensitivity of minus 56 dBm for a bit-error-rate (BER) of 5 * 10-9. The BER performance with frequency offset and input power variation is also investigated.

A monolithic temperature-compensated 160 MHz current controlled oscillator

In this paper the authors present simulation and measurement results of a monolithic 160 MHz multivibrator circuit. A simple temperature compensation technique is proposed. The circuit was realised in a Si 1.3 /spl mu/m bipolar semicustom process with an f/sub t/ of 8.3 GHz. Measurements show that the temperature sensitivity can be improved from 2125 ppm//spl deg/C to 187 ppm//spl deg/C.

Burst Mode Bipolar Laser Driver for a Multipoint to Point Passive Optical Network at 155.52 Mbit/s

A burst mode bipolar laser driver for a multipoint to point passive optical network at 155.52 Mbit/s has been developed. This integrated circuit is specially designed for commercially available packaged lasers, and is optimised for low power dissipation and cost. Measurements show a rise and fall-time of 1.2 ns.