ABSTRACT High order modulation formats allow to reach higher spectral efficiency and data rate. H... more ABSTRACT High order modulation formats allow to reach higher spectral efficiency and data rate. However, their practical implementation is limited by their reduced tolerance to noise and to the optical signal power that can be launched into the fiber without generating excessive nonlinear signal distortions. In this paper, it is demonstrated that Turbo Equalization routines can be used to mitigate performance degradations stemming from optical fiber propagation effects both in optical fiber dispersion managed and unmanaged coherent detection links. The effectiveness of this solution is analyzed both numerically and experimentally for different transmission systems.
Combined effect of polarization mixing and differential group delay (DGD) on sinusoidal and rando... more Combined effect of polarization mixing and differential group delay (DGD) on sinusoidal and random jitter tolerance is investigated. Requirements for tolerable DGD, loop bandwidth and loop delay are extrapolated.
ABSTRACT The relatively high phase noise of coherent optical systems poses unique challenges for ... more ABSTRACT The relatively high phase noise of coherent optical systems poses unique challenges for forward error correction (FEC). In this letter, we propose a novel semianalytical method for selecting combinations of interleaver lengths and binary Bose-Chaudhuri-Hocquenghem (BCH) codes that meet a target post-FEC bit error rate (BER). Our method requires only short pre-FEC simulations, based on which we design interleavers and codes analytically. It is applicable to pre-FEC BER $sim 10^{-3}$ , and any post-FEC BER. In addition, we show that there is a tradeoff between code overhead and interleaver delay. Finally, for a target of $10^{-5}$ , numerical simulations show that interleaver-code combinations selected using our method have post-FEC BER around $2times $ target. The target BER is achieved with 0.1 dB extra signal-to-noise ratio.
Optical Transmission Systems, Subsystems, and Technologies IX, 2011
ABSTRACT We propose and demonstrate a 2 × 2 multiple-input multiple-output (MIMO) wireless over f... more ABSTRACT We propose and demonstrate a 2 × 2 multiple-input multiple-output (MIMO) wireless over fiber transmission system. Seamless translation of two orthogonal frequency division multiplexing (OFDM) signals on dual optical polarization states into wireless MIMO transmission at 795.5 Mbit/s net data rate is enabled by using digital training-based channel estimation. A net spectral efficiency of 2.55 bit/s/Hz is achieved.
2011 International Topical Meeting on Microwave Photonics jointly held with the 2011 Asia-Pacific Microwave Photonics Conference, 2011
We present a photonic generation and down-conversion method for realizing a 40Gbps wireless link ... more We present a photonic generation and down-conversion method for realizing a 40Gbps wireless link at the 75–110 GHz band exploiting the recent advances in photonic coherent detection technologies and digital signal processing. Furthermore, we analyze the capacities of hybrid optical fiber-wireless links at the 75–110GHz band, and propose several approaches to overcome the challenges towards 100Gbps wireless capacity.
LEOS 2008 - 21st Annual Meeting of the IEEE Lasers and Electro-Optics Society, 2008
Maximum likelihood based feedforward RF carrier synchronization scheme is proposed for a coherent... more Maximum likelihood based feedforward RF carrier synchronization scheme is proposed for a coherently detected phase-modulated radio-over-fiber link. Error-free demodulation of 100 Mbit/s QPSK modulated signal is experimentally demonstrated after 25 km of fiber transmission.
ABSTRACT High order modulation formats allow to reach higher spectral efficiency and data rate. H... more ABSTRACT High order modulation formats allow to reach higher spectral efficiency and data rate. However, their practical implementation is limited by their reduced tolerance to noise and to the optical signal power that can be launched into the fiber without generating excessive nonlinear signal distortions. In this paper, it is demonstrated that Turbo Equalization routines can be used to mitigate performance degradations stemming from optical fiber propagation effects both in optical fiber dispersion managed and unmanaged coherent detection links. The effectiveness of this solution is analyzed both numerically and experimentally for different transmission systems.
Combined effect of polarization mixing and differential group delay (DGD) on sinusoidal and rando... more Combined effect of polarization mixing and differential group delay (DGD) on sinusoidal and random jitter tolerance is investigated. Requirements for tolerable DGD, loop bandwidth and loop delay are extrapolated.
ABSTRACT The relatively high phase noise of coherent optical systems poses unique challenges for ... more ABSTRACT The relatively high phase noise of coherent optical systems poses unique challenges for forward error correction (FEC). In this letter, we propose a novel semianalytical method for selecting combinations of interleaver lengths and binary Bose-Chaudhuri-Hocquenghem (BCH) codes that meet a target post-FEC bit error rate (BER). Our method requires only short pre-FEC simulations, based on which we design interleavers and codes analytically. It is applicable to pre-FEC BER $sim 10^{-3}$ , and any post-FEC BER. In addition, we show that there is a tradeoff between code overhead and interleaver delay. Finally, for a target of $10^{-5}$ , numerical simulations show that interleaver-code combinations selected using our method have post-FEC BER around $2times $ target. The target BER is achieved with 0.1 dB extra signal-to-noise ratio.
Optical Transmission Systems, Subsystems, and Technologies IX, 2011
ABSTRACT We propose and demonstrate a 2 × 2 multiple-input multiple-output (MIMO) wireless over f... more ABSTRACT We propose and demonstrate a 2 × 2 multiple-input multiple-output (MIMO) wireless over fiber transmission system. Seamless translation of two orthogonal frequency division multiplexing (OFDM) signals on dual optical polarization states into wireless MIMO transmission at 795.5 Mbit/s net data rate is enabled by using digital training-based channel estimation. A net spectral efficiency of 2.55 bit/s/Hz is achieved.
2011 International Topical Meeting on Microwave Photonics jointly held with the 2011 Asia-Pacific Microwave Photonics Conference, 2011
We present a photonic generation and down-conversion method for realizing a 40Gbps wireless link ... more We present a photonic generation and down-conversion method for realizing a 40Gbps wireless link at the 75–110 GHz band exploiting the recent advances in photonic coherent detection technologies and digital signal processing. Furthermore, we analyze the capacities of hybrid optical fiber-wireless links at the 75–110GHz band, and propose several approaches to overcome the challenges towards 100Gbps wireless capacity.
LEOS 2008 - 21st Annual Meeting of the IEEE Lasers and Electro-Optics Society, 2008
Maximum likelihood based feedforward RF carrier synchronization scheme is proposed for a coherent... more Maximum likelihood based feedforward RF carrier synchronization scheme is proposed for a coherently detected phase-modulated radio-over-fiber link. Error-free demodulation of 100 Mbit/s QPSK modulated signal is experimentally demonstrated after 25 km of fiber transmission.
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Papers by Darko Zibar