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This paper investigates the transmission of an injection-locked optical orthogonal frequency-division multiplexing (ILO-OFDM) scheme over an optical fiber. In the ILO-OFDM system, an optically injection-locked semiconductor laser is utilized to directly modulate the OFDM signal on the optical carrier. With a sufficiently large injection strength and a negative shift of the detuning frequency, the modulation sidebands become asymmetric similar to a single sideband modulation (SSB). The SSB spectrum is advantageous for minimizing the chromatic dispersion-induced power variation. Using simulation we show that ILO-OFDM system can be used to compensate for chromatic dispersion in long-haul applications. [ABSTRACT FROM AUTHOR]

A modeling approach to power amplifier design for implementation in OFDM radio units is presented. The power amplifier model assesses the impact of linear memory effects within the system using a Wiener representation, and employs a linear novel parametric estimation technique using Hilbert space. In addition, in order to model the nonlinear memory effects the previous topology is generalized by inserting the truncated Volterra filter before the static nonlinearity. Predistortion based on the Hammerstein model is introduced to deal with the nonlinear response. The new general algorithm is proposed to evaluate the Hammerstein model parameters for an OFDM system. A representative test bed was designed and implemented. The assessment of the new methods for PA and PD modeling are confirmed by experimental measurements. The measurement results reveal the preference of the new techniques over the existing approaches. [ABSTRACT FROM AUTHOR]