Techniques for the compensation for chromatic-dispersion effects in fiber-wireless systems

Fibre-wireless systems have been extensively studied over the past years with a view towards the development of broadband-access solutions [1–3]. In such networks, base stations can be made simple and compact when the radio-frequency (RF) signals are generated in the central stations, but severe constraints are thus imposed on the fiber links. One of the major problems encountered is the dispersion-induced RF power fading, which is also known as the carrier-suppression effect [4]. When using conventional intensity modulation of an optical source (Figure 1), the resulting signal consists of an optical carrier and two sidebands. The three spectral components of such an optical double-sideband (ODSB) signal experience different propagation speeds in the fiber. As the photo-detected RF signal results from the combination of the beating of each sideband with the optical carrier, destructive interference may cause cancellation of the power, P
RF
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