Search

Fast‐OFDM‐based intensity‐modulation and direct‐detection (IM/DD) has been proposed for deployment of cost‐efficient optical access networks, due to its implementation simplicity and high spectral efficiency. In this article, the accuracy of the generalised memory polynomial (GMP) for the non‐linear modelling of optical Fast‐OFDM links is studied, including memory effects and considering different model parameters. After model validation using measured data of a 10 km single mode fibre link, the GMP is used for performance investigations of a distortion compensation approach to optical Fast‐OFDM, for up to 16PAM modulation formats and different number of Fast‐OFDM subcarriers. This study firstly reports the performance results of optical 16PAM‐Fast‐OFDM systems using either 2PAM‐ or 4PAM‐based training signals for digital post‐distortion and FFT‐based channel estimation, and firstly investigates the influence of the zero padding (ZP) length on the performance of optical Fast‐OFDM. Excellent performance improvements are achieved using the proposed distortion compensation scheme, relative to conventional system implementation. [ABSTRACT FROM AUTHOR]

The performance of a noncoherent decoder based on a pair of distributed‐based transversal filters architecture is reported. Analysis based on experimental results validates the decoder as a proof‐of‐concept using microwave integrated circuits. Front‐end transversal filters are designed with large degree of freedom to generate and correlate temporal phase‐coded signals. Receiving functions are aligned with slots of spectrally encoded channels to make available spectral amplitude‐coding electronic‐code division multiple access. Noncoherent ultra‐wideband receiver concepts are applied to model the decoder synchronized to shot noise pulse trains. The despreading operation involves capturing sufficient amount of energy to demodulate matched and unmatched users. Electronic transversal filters implemented with a suitable number of taps allow bipolar detection of concurrent users whereas the noncoherent reception of energy of sub‐bands is fundamental to achieve orthogonality among channels, as we show in this article. [ABSTRACT FROM AUTHOR]

In this letter, we present an exact and generic semianalytical tool for the noise characterization of distributed preamplifiers suitable for very high-capacity optical transmission. The accuracy and flexibility of this tool allow the noise characterization to be effected in terms of input and output current and/or voltage spectral density. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 30: 416–418, 2001. [ABSTRACT FROM AUTHOR]