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The use of ultra-wide band (UWB) radio technique is proposed as a viable solution for the distribution of highdefinition audio/video content in fiber-to-the-home (FTTH) networks. The approach suitability is demonstrated by the transmission of standards-based UWB signals at 1.25 Gbit/s along different FTTH fiber links with 25 km up to 60 km of standard single-mode fiber length in a laboratory experiment. Experimental results suggest that orthogonal frequency division multiplexed UWB signals exhibit better transmission performance in FFTH networks than impulse radio UWB signals. Index Terms-Optical communications, Fiber-To-The-Home access networks, Ultra-Wide Band (UWB). I. INTRODUCTION ltra-Wide Band (UWB) has been indicated as one of the most promising techniques to be used in wireless communication networks. The growing interest in this technique is due to its low self-interference, tolerance to multipath fading, low probability of interception and capability of passing through walls while maintaining the communication [1]. Nowadays, UWB is appointed for high bit-rate wireless communications at picocell range, namely as a replacement of high definition (HD) video/audio cabling [2]. This paper proposes to extend this application to the distribution of HD audio/video content by the optical modulation and transmission of UWB signals in their native format through fiber-to-the-home (FTTH) access networks. This approach exhibits several advantages: (i) FTTH networks provide bandwidth enough to distribute a large number of UWB signals, as each one of them can occupy up to 7 GHz in current UWB regulation [3]. (ii) No trans-modulation is required at user premises. HD audio/video content is transmitted through the fibers in UWB native format. (iii) No frequency up-conversion is required at customer premises. The UWB signals are photo-detected, filtered, amplified and radiated directly to establish the wireless connection. (iv) FTTH networks are transparent to the specific UWB implementation Manuscript received 6th December 2007.

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The discrete changes model (DCM) of inter-core crosstalk (ICXT) in weakly-coupled homogeneous multi-core fibers (MCFs) is generalized to a dual polarization (DP) scheme. This model provides theoretical expressions for the two polarization fields of the ICXT at the MCF output. Therefore, it may be of particular interest in the design of direct-detection MCF systems where the photodetected ICXT results mainly from the beating between the ICXT field at the MCF output and the carrier of the interfered core. The DP-DCM is validated by comparison of the mean ICXT power and ICXT field amplitude estimates with the ones obtained with a rigorous, yet much more computationally demanding, model based on the coupled local mode theory (CLMT). Good agreement between the mean ICXT power estimates obtained with the DP-DCM and CLMT is observed when the inter-core coupling coefficient variation along the MCF is small. Good agreement is also observed when comparing the probability density functions of the ICXT field amplitude. Index Terms-multi-core fibers, crosstalk, discrete changes model, coupled local mode theory, dual polarization.