Joris Van Kerrebrouck

A Wide-Band, 5-Tap Transversal Filter With Improved Testability for Equalization up to 84 Gb/s

A millimeter wave integrated transversal filter operating at up to 84 Gb/s is presented. The implemented topology offers improved testability, which allows for filter characterization in both the time and frequency domain. The filter has an input and output return loss better than 10 dB up to 67 GHz. Using this filter, frequency equalization of an NRZ input to either an NRZ or a duobinary output is demonstrated at 84 Gb/s across a channel consisting of a 5 cm differential grounded coplanar waveguide trace and a pair of 80 cm coaxial cables. The filter is implemented in 130 nm SiGe BiCMOS process, has a die area of 2.5 mm × 1.4 mm and consumes 210 mW from a 2.5 V power supply.

An asymmetric high serial rate TDM-PON with single carrier 25 Gb/s upstream and 50 Gb/s downstream

We report a 2:1 rate asymmetric high serial rate time division multiplexing passive optical network (TDM-PON) with single carrier 25 Gb/s upstream and 50 Gb/s downstream. In the upstream, we present a first 25 Gb/s three-level modulated burstmode receiver employing a 1/4-rate linear burst-mode avalanch photodiode transimpedance amplifier and a custom decoder IC. We successfully demonstrated burst-mode sensitivity of -20.4 dBm with 18 dB dynamic burst-to-burst for 25 Gb/s upstream links. In another direction, a downstream in upper O-band is proposed and demonstrated with three-level duo-binary modulation at 50 Gb/s in real time. The upstream and downstream transmission experiments show that the proposed asymmetric 50 G/25 G high serial rate TDM-PON can support ≥32 users while covering more than 20 km reach.

ATTO: Wireless Networking at Fiber Speed

To provide a tremendous wireless capacity (100Gbps/m2) and latencies <10μs, ultra-small floor-integrated cells are proposed. RF-over-fiber, coherent communication and a dedicated 2D PON structure support the interconnection and selection of the cells and allow to minimize the required transceiver electronics.

Maximally Flat and Least-Square Co-Design of Variable Fractional Delay Filters for Wideband Software-Defined Radio

This paper describes improvements in a Farrow-structured variable fractional delay (FD) Lagrange filter for all-pass FD interpolation. The main idea is to integrate the truncated sinc into the Farrow structure of a Lagrange filter, in order that a superior FD approximation in the least-square sense can be achieved. Its primary advantages are the lower level of mean-square-error (MSE) over the whole FD range and the reduced implementation cost. Extra design parameters are introduced for making the trade-off between MSE and maximal flatness under different design requirements. Design examples are included, illustrating an MSE reduction of 50% compared to a classical Farrow-structured Lagrange interpolator while the implementation cost is reduced. This improved variable FD interpolation system is suitable for many applications, such as sample rate conversion, digital beamforming and timing synchronization in wideband software-defined radio (SDR) communications.

Real-time 100 Gbps/lambda/core NRZ and EDB IM/DD transmission over multicore fiber for intra-datacenter communication networks

A BiCMOS chip-based real-time intensity modulation/direct detection spatial division multiplexing system is experimentally demonstrated for both optical interconnects. 100 Gbps/λ/core electrical duobinary (EDB) transmission over 1 km 7-core multicore fiber (MCF) is carried out, achieving KP4 forward error correction (FEC) limit (BER < 2E-4). Using optical dispersion compensation, 7 × 100 Gbps/λ/core transmission of both non-return-to-zero (NRZ) and EDB signals over 10 km MCF transmission is achieved with BER lower than 7% overhead hard-decision FEC limit (BER < 3.8E-3). The integrated low complexity transceiver IC and analog signal processing approach make such a system highly attractive for the high-speed intra-datacenter interconnects.

16 Gbps RoF link at 20 ghz carrier frequency using a silicon photonics transmitter and receiver

In future radio access networks, radio-over-fiber links will be a key enabling technology. A link which is cost-effective in both deployment and operation will be of paramount importance to the development of such networks. Using silicon photonics for the transmitter and receiver is a cost-effective and high-performance solution. In this work we present a link which can transport up to 16 Gbps 16-QAM data on a 20 GHz carrier over 5 km of SMF. The transmitter is a III-V-on-Si directly modulated laser and the receiver is a Ge-on-Si photodetector on a silicon photonic integrated circuit, co-integrated with a SiGe BiCMOS TIA. This is to the best of our knowledge the first Si PIC based RoF link with a directly modulated laser.

Adaptive Transmit-Side Equalization for Serial Electrical Interconnects at 100 Gb/s Using Duobinary

The ever-increasing demand for more efficient data communication calls for new, advanced techniques for high speed serial communication. Although newly developed systems are setting records, off-line determination of the optimal equalizer settings is often needed. Well-known adaptive algorithms are mainly applied for receive-side equalization. However, transmit-side equalization is desirable for its reduced linearity requirements. In this paper, an adaptive sign–sign least mean square equalizer algorithm is developed applicable for an analog transmit-side feed-forward equalizer (FFE) capable of transforming non-return-to-zero modulation to duobinary (DB) modulation at the output of the channel. In addition to the derivation of the update strategy, extra algorithms are developed to cope with the difficult transmit–receive synchronization. Using an analog six tap bit-spaced equalizer, the algorithm is capable of optimizing DB communication of 100Gb/s over 1.5-m Twin-Ax cable. Both simulations and experimental results are presented to prove the capabilities of the algorithm demonstrating automated determination of FFE parameters, such that error-free communication is obtained (BER

40-Gb/s TDM-PON downstream with low-cost EML transmitter and 3-level detection APD receiver

<10^{-13}

40-Gb/s TDM-PON Downstream Link With Low-Cost EML Transmitter and APD-Based Electrical Duobinary Receiver

using PRBS9).