1.25 Gbit/s ITU-T G.984.2 burst-mode transimpedance amplifier without reset pins

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A 10Gb/s burst-mode TIA with on-chip reset/lock CM signaling detection and limiting amplifier with a 75ns settling time

Emerging symmetric 10Gb/s passive optical network (PON) systems aim at high network transmission efficiency by reducing the RX settling time that is needed for RX amplitude recovery in burst-mode (BM). A conventional AC-coupled BM- RX has an inherent tradeoff between short settling time and decision threshold droop, which makes an RX settling time shorter than 400ns hard to achieve. Some techniques have been developed to overcome this limitation, demonstrating a settling time of 150 to 200ns. Our previous work uses feed-forward automatic offset compensation (AOC) to achieve a response time as short as 25.6ns. However, a feed-forward scheme using peak detectors is intrinsically less accurate and results in relatively high power consumption. In this paper, we present a DC-coupled 10Gb/s BM-TIA and burst-mode limiting amplifier (BM- LA) chipset that uses a feedback type AOC circuit with switchable loop BW. This new technique is capable of removing input DC offset in less than 75ns, and offers continuous decision threshold tracking during payload, to cope with the maximum length of CID. The differential TIA output port senses a CM reset signal provided by the succeeding BM-LA, and activates an on-chip reset and lock function. This BM-LA also integrates auto reset/activity generation circuits providing the AOC BW switching signal, so that this time-critical signal is not required from the PON system

Experiments on a 10 Gb/s fast-settling high-sensitivity burst-mode receiver with on-chip auto-reset for 10G-GPONs [Invited]

This paper presents a 10 Gb/s avalanche-photodiode-based DC-coupled reshaping and reamplifying (2R) burst-mode receiver with on-chip auto-reset generation and multiple data rate support, designed for 10G-GPONs. A short 2R settling time of 75 ns (150 ns for lower-rate operation), a high receiver sensitivity of -31.3 dBm, and a large loud/soft ratio of 25.3 dB are demonstrated at 2.5/5/10 Gb/s in burst-mode operation. Allowing multi-rate operation without external reset signals, it shows great potential for use in emerging symmetric 10G-GPON systems and allows for more flexible future optical access networks

Mixed Use of Analytical Derivatives and Algorithmic Differentiation for NMPC of Robot Manipulators

International audienceIn the context of nonlinear model predictive control (NMPC) for robot manipulators, we address the problem of enabling the mixed and transparent use of algorithmic differentiation (AD) and efficient analytical derivatives of rigid-body dynamics (RBD) to decrease the solution time of the subjacent optimal control problem (OCP). Efficient functions for RBD and their analytical derivatives are made available to the numerical optimization framework CasADi by overloading the operators in the implementations made by the RBD library Pinocchio and adding a derivative-overloading feature to CasADi. A comparison between analytical derivatives and AD is made based on their influence on the solution time of the OCP, showing the benefits of using analytical derivatives for RBD in optimal control of robot manipulators

Crystallization diagram for antisolvent crystallization of lactose : using design of experiments to investigate continuous mixing- induced supersaturation

This study investigates the effects of key process parameters of continuous mixing-induced supersaturation on the antisolvent crystallization of lactose using D-optimal Design of Experiments (DoE). Aqueous solutions of lactose were mixed isothermally with antisolvents using a concentric capillary mixer. Process parameters investigated were the choice of antisolvent (acetone or isopropanol), concentration of lactose solution, total mass flow rate, and the ratio of mass flow rates of lactose solution and antisolvent. Using a D-optimal DoE a statistically significant sample set was chosen to explore and quantify the effects of these parameters. The responses measured were the solid state of the lactose crystallized, induction time, solid yield and particle size. Mixtures of α-lactose monohydrate and β-lactose were crystallized under most conditions with β-lactose content increasing with increasing amount of antisolvent. Pure α-lactose monohydrate was crystallized using acetone as the antisolvent, with mass flow ratios near 1:1, and near saturated solutions of lactose. A higher resolution DoE was adopted for acetone and was processed using multivariate methods to obtain a crystallization diagram of lactose. The model was used to create an optimized process to produce α-lactose monohydrate and predicted results agreed well with those obtained experimentally, validating the model. The solid state of lactose, induction time, and solid yield were accurately predicted