Bidirectional transmission at 10 Gbit/s using 3.125 GBaud PDM-QPSK over 100 km of SMF is investigated. We observe no penalty for transmission of 10 GHz spaced channels. Preamplification improves the receiver sensitivity from -45.9 dBm to -53.0 dBm. © 2010 Optical Society of America.

Bidirectional 10 Gbit/s long-reach WDM-PON using digital coherent receivers

High spectral efficiency offered by the coherent optical communication links makes them attractive for the next-generation optical communication links. Using advanced modulation schemes such as dual-polarization quadrature-amplitude modulation (DP-QAM) data rates beyond 200 Gb/s can be achieved. A key component of such links is the wide-bandwidth and high-linearity coherent optical receiver. In this paper, we present a fully differential (FD) optical receiver architecture consisting of a variable-gain transimpedance amplifier (VG-TIA) followed by a VG amplifier (VGA). The proposed optical receiver employs a dual-feedback automatic gain control (AGC) loop that controls both the front-end VG-TIA and the following VGA to achieve both low-noise and high-linearity operation. A new photodiode (PD) dc current cancellation scheme is developed and implemented for the full differential front-end TIA. A prototype dual-TIA chip is fabricated in a 0.13- $\mu \text{m}$ SiGe BiCMOS process. The presented TIA achieves 20-pA/ $\sqrt {\text {Hz}}$ input-referred noise (IRN) density, 27-GHz, 3-dB bandwidth, and 1.5% total harmonic distortion (THD) at 1-mApp input PD current and 500-mVpp output voltage swing. This enables the 34-GBd operation with the bit error rate (BER) of $10^{-10}$ and $5.4\times 10^{-4}$ using DP-QPSK and DP-16-QAM formats at optical signal-to-noise ratios (OSNRs) of 25 and 30 dB, respectively, demonstrating the 100- and 200-Gb/s single wavelength optical coherent receiver operation. The dual-TIA chip occupies an area of $1.4\,\,\text {mm}\times 1.6$ mm and consumes 313 mW per channel at 34 GBd from a 3.3-V supply.

34-GBd Linear Transimpedance Amplifier for 200-Gb/s DP-16-QAM Optical Coherent Receivers

Fast, low-noise and sensitive avalanche photo-receivers are needed for surging short-reach photonic applications. Limitations concerning bandwidth, throughput and energy consumption should be overcome. In this work, we comprehensively study the performance opportunities provided by avalanche p-i-n photodetectors with lateral silicon-germanium-silicon heterojunctions. Our aim is to circumvent the need for chip-bonded electronic amplifiers. In particular, we demonstrate that avalanche photodetectors based on silicon-germanium-silicon heterostructures yield reliable opto-electrical performances, with high gain-bandwidth products up to 480 GHz and low effective ionization ratios down to 0.15. Moreover, they improve power sensitivities for high-speed optical signals and have a low energy dissipation of only a few fJ per received information bit. These results pave the way for high-performing receivers for energy-aware data links, in next-generation short-distance data communications.

/pdf/silicon-germanium-avalanche-receivers-with-fj-bit-energy-28re04htja.pdf

Silicon-Germanium Avalanche Receivers With fJ/bit Energy Consumption

A heterogeneously integrated widely tunable III-V-on-silicon ring laser with unidirectional operation is demonstrated. 40 nm tuning range (from 1560 nm to 1600 nm) is obtained using the Vernier effect between two ring resonators incorporated in the ring laser cavity. Unidirectional operation is obtained by integrating a DBR reflector coupling the clockwise and counterclockwise mode of the ring laser cavity. Unidirectional operation is obtained over the entire tuning range with about 10 dB suppression of the clockwise mode. The laser linewidth is lower than 1 MHz over the entire tuning range, down to 550 kHz in the optimum operation point. The waveguide-coupled output power is above 0 dBm over the entire tuning range.

https://biblio.ugent.be/publication/8527616/file/8527619.pdf

Unidirectional, widely-tunable and narrow-linewidth heterogeneously integrated III-V-on-silicon laser

Through co-design of a dual SiGe transimpedance amplifier and an integrated silicon photonic circuit, we realized for the first time an ultra-compact and low-power silicon single-polarization coherent receiver operating at 40 GBd. A bit-error rate of <;3.8 × 10
 -3
 was obtained for an optical signal-to-noise ratio of 14 dB for QPSK modulation (80 Gb/s), and 26.5 dB for 16-QAM (160 Gb/s). We also demonstrate robust performance of the receiver over temperature and wavelength.

/pdf/a-40-gbd-qpsk-16-qam-integrated-silicon-coherent-receiver-4u5ogfqchg.pdf

A 40-GBd QPSK/16-QAM integrated silicon coherent receiver

We demonstrate the codesign and cointegration of an ultracompact silicon photonic receiver and a low-power-consumption (155 mW/channel) two-channel linear transimpedance amplifier array. Operation below the forward error coding (FEC) threshold both for quadrature phase-shift keying (QPSK) and 16-quadrature amplitude modulation (QAM) at 28 Gbaud is demonstrated.

/pdf/compact-low-power-consumption-28-gbaud-qpsk-16-qam-jk3nqftxfs.pdf

J. Bauwelinck

Papers

Compact Low-Power-Consumption 28-Gbaud QPSK/16-QAM Integrated Silicon Photonic/Electronic Coherent Receiver