Cookies Policy
We use cookies to improve our site and your experience. By continuing to browse our site you accept our cookie policy. Find out More
Close
  • Menu
About

About

I am a PhD student at the MAP-Tele Doctoral Programme in Telecommunications and a researcher at INESC TEC, in the CTM group. My main interests include optical fiber communication systems, specifically nonlinearity mitigation techniques and multimode fibers. My thesis proposal is entitled "Phase-Conjugated Twin Waves for Space-Division Multiplexed Systems", where I proposed to study spectrally efficient PCTW techniques to overcome the spectral efficiency loss inherent to the PCTW technique. 

Interest
Topics
Details

Details

Publications

2018

Experimental Evaluation of Resonant Tunnelling Diode Oscillators Employing Advanced Modulation Formats

Authors
Tavares, JS; Pessoa, LM; Salgado, HM;

Publication
International Conference on Transparent Optical Networks

Abstract
The performance of Resonant Tunnelling Diode (RTD) oscillators with an optical window is evaluated experimentally, in the transmission of advanced modulation formats using electrical and optical modulation, for the first time. Additionally, the impact of phase noise in the transmission performance is also assessed. © 2018 IEEE.

2017

Analysis of resonant tunnelling diode oscillators under optical modulation

Authors
Tavares, JS; Pessoa, LM; Figueiredo, JML; Salgado, HM;

Publication
International Conference on Transparent Optical Networks

Abstract
In this paper, we investigate the optical modulation characteristics of a resonant tunnelling diode (RTD) oscillator. This preliminary work on the first RTD-PD oscillators with an optical window available from the iBROW project demonstrate that this device can effectively be used to accomplish amplitude and frequency modulation with light injection. © 2017 IEEE.

2017

Nonlinear Compensation Assessment in Few-Mode Fibers via Phase-Conjugated Twin Waves

Authors
Tavares, JS; Pessoa, LM; Salgado, HM;

Publication
JOURNAL OF LIGHTWAVE TECHNOLOGY

Abstract
In this paper, we further explore the concept of phase-conjugated twin waves (PCTW) for nonlinear cancellation in space-division multiplexed (SDM) systems. Previously, we demonstrated that the PCTW technique can successfully provide nonlinear cancellation in SDM systems. In this paper, we investigate the cases where two and four spatial modes are copropagating in a multimode fiber, considering three link lengths (1000, 3200, and 8000 km). Weak-and strong-coupling regimes are also evaluated. Our numerical simulation results show an average performance improvement > 10 dB after a 1000 km transmission link.

2015

Phase Conjugated Twin Waves Based Transmission in Few Modes Fibers

Authors
Tavares, JS; Pessoa, LM; Salgado, HM;

Publication
2015 17th International Conference on Transparent Optical Networks (ICTON)

Abstract
Spatial division multiplexing (SDM) is seen as an effective technique to overcome the present limits of fiber capacity and satisfy future bandwidth requirements, by substantially increasing optical transport capacities [1-5]. Similarly to single-mode fiber based modern telecommunication systems, the nonlinear penalties will eventually become the ultimate limiting factor in SDM systems, arising from crosstalk effects in multimode core or few mode fibers, which generate intramodal and intermodal nonlinearities. Here we explore the concept of conjugated twin waves in few mode fibers based SDM optical systems, as a means to overcome these nonlinear impairments and assess the performance of SDM systems for different PCTW configurations and coupling regimes. Our numerical simulation results show that this technique is an effective means to overcome the nonlinear impairments arising in mode division multiplexed systems, improving performance by up to 10 dB, in the strong coupling regime.

2014

Experimental evaluation of a digitized fiber-wireless system employing sigma delta modulation

Authors
Pessoa, LM; Tavares, JS; Coelho, D; Salgado, HM;

Publication
OPTICS EXPRESS

Abstract
Digitized radio-over-fiber (D-RoF) transport schemes are being pointed as viable alternative solutions to their analog counterparts, in order to avoid distortion/dynamic range problems. Here we propose a novel D-RoF architecture that takes advantage of a bandpass sigma-delta modulator at the transmitter which subsequently permits the usage of a simpler/cheaper base station that avoids the employment of a digital to analog converter. The proposed architecture exploits the properties of the digital signal to enable the extraction of an higher carrier frequency through the employment of a bandpass filter. Furthermore, we present a comprehensive analysis regarding the impact of a low-cost electro-optic modulation on the quality of received demodulated signal. Finally, a comparison performance analysis between the conventional D-RoF and the proposed architecture is presented. We conclude that although the proposed architecture performs similarly to conventional D-RoF schemes, it is more competitive for either upgrading installed systems as well as for new deployments. (C) 2014 Optical Society of America