Optical broadband in-home networks for converged service delivery

Broadband access networks, and in particular fibre-to-the-home (FTTH) networks, are offering abundantly available bandwidth in the local loop with high quality of services. Under such broadband connectivity conditions, in-home networks should not represent the bottleneck for high capacity service delivery to consumers. However, current in-home networks are a blend of different networks, each optimized for a particular kind of services and cannot meet such high capacity and quality of service requirements. Converging the delivery of various services over a single wired home network will provide an immediate advantage of reducing the costs and complexity for both network operators and end users. Optical fibre is attractive as the medium for such converged in-home networks thanks to its low loss, large bandwidth, electromagnetic resilience to interference (EMI). The main work presented in this thesis aims at developing low-cost, high speed, optical broadband in-home networks which can support the distribution of multiple-format services. 1 mm core diameter plastic optical fibre (POF) is a promising transmission medium for short-range communication. The main advantages of POF are its easy installation, easy splicing and the possibility of using lowcost optical transceivers. POF technologies for the transport of broadband wireless signals and converged wired and wireless services are explored in this thesis. By employing radio-over-POF technologies, a full solution based on an eye-safe optical transmitter and graded-index POF has been developed. A prototype of real-time high definition (HD) video broadcasting using ultra wideband (UWB) technologies over a large-core POF network is demonstrated for the first time. In order to study the convergence capability of a POF based optical backbone, techniques to introduce multiple services over a simple POF architecture have been investigated. Converged delivery of wired and wireless signals (UWB, DVB-T), and multiple wireless (WiMAX, LTE, UWB) signals are discussed in detail. Discrete multi tone (DMT) modulation format and fractional QAM (3×2N) schemes are employed for the baseband stream to achieve an improved spectrum efficiency. Furthermore, employing a bit-and power-loading algorithm, a flexible POF backbone utilizing frequency reuse for wireless and wired signals is presented. Finally, from the network perspective, most studies on POF so far have been based on a point-to-point (P2P) network topology. This thesis investigates point-to-multipoint (P2MP) POF infrastructures with different topologies (tree and bus). A POF based passive optical network (PON) concept is proposed with various transmission scenarios. The system performance of single/multiple service delivery, unique/bi-directional transmission, and different optical transceiver concepts is investigated in detail. It is shown that a distribution of converged multi-Gigabit/s baseband stream and a UWB service over a POF-PON architecture to four end users can be achieved. Based on the studies mentioned above, the world’s first field trial of G.hn standard over single POF-PON for triple-play service distribution is demonstrated using commercially available integrated POF devices. All the techniques, concepts, system designs presented in this thesis underline the strong potential of optical fibres (especially POF) for the delivery of broadband services to wired and wireless devices for in-home networks. Thus, the benefits of broadband FTTH networks can be extended to end users via versatile fibre-in-the-home (FITH) solutions.