Search

Energy efficiency has become a major paradigm in the design and operation of future telecommunication networks. Recent studies show that the aggregate power consumption of in-building IT networks (residential and office) is massive and comparable with that of data centers due to the large number of buildings. In this paper, we analyze the energy efficiency of next-generation in-building IT networks to deliver high-speed mobile access to end users via integrated optical/wireless networks using Radio-over-Fiber (RoF) technology. Based on a validated energy efficiency model, our results show that although individual point-to-point RoF links are not as energy efficient as legacy Baseband-over-Fiber links, RoF networks may actually be more energy-efficient when designed keenly with small cells sizes and when the static energy consumption of the remote units is above a particular threshold. Under the assumptions used in this paper, we show that the DRoF-based architectures can be designed to more energy efficient for cell sizes

Future in-building networks will most likely consist of two segments - optical and wireless; they will use little or no copper media. In previous work, we've analysed a number of green optical/wireless in-building network designs. In this paper, we present a study of why, where and how these networks can be deployed. We consider three different technologies: legacy Baseband-over-Fiber, Analog Radio-over-Fiber and Digital Radio-over-Fiber, in two different deployment scenarios: indoor networks and high user density open space/outdoor networks. We also consider two different deployment goals: improved coverage and increased capacity. Our results indicate that for indoor networks cell sizes should be between ∼10 m – 15 m with DRoF technologies while for high user density outdoor/open-space networks, cell sizes 80 m for open space buildings).

Radio-over-Fiber (RoF) based network architectures would allow centralization of signal processing and signal conditioning functions and simple, cost-effective remote units at the cell site. RoF technology results in remote units with few components, however, certain aspects of the technology may inadvertently lead to high power consuming components. In this paper, we experimentally investigate the effect of electrical-optical-electrical (E/O/E) loss and signal bandwidth on the energy consumption of analog and digitized RoF (ARoF and DRoF) links. We also analyze the energy efficiency of multiple services on a single RoF distribution network. Our results show that E/O/E loss significantly degrades the energy efficiency of the ARoF links. DRoF is robust to the E/O/E loss on the optical link but is affected by the loss due to reconstruction of the radio frequency signal at higher Nyquist zones. We also show that increasing the bandwidth improves the energy efficiency. Finally, we demonstrate that the extra energy savings from having multiple services on a single RoF link depends on the wireless environment.

With the growing popularity of high-performance computing devices such as tablets and smart-phones, and the growing trends of cloud-based services, forecasts indicate that the majority of Internet traffic will originate from inside of the buildings. Thus indoor network infrastructure needs to provide both better capacity and better coverage. Meanwhile, energy efficiency of the network becomes an additional requirements on the network design, due to the rising concern of the carbon footprint of telecommunication industry over the past few years. In this paper, we discuss a few fundamental trade-offs that need to be considered when designing energy-efficient networks. We also discuss the energy efficiency of Radio-over-Fiber (RoF) links and compare RoF-based architectures with legacy Basebandover- Fiber (BoF) for two scenarios: growing network capacity and improving network coverage. We demonstrate that the understanding and the analysis of main energy hogs and their trade-offs in various network architectures is a key factor in optimizing the design of energy-efficient network architecture.

We demonstrate, for the first time, simultaneous routing of wireless 2 Gb/s IR-UWB and 1.25 Gb/s wired services using XGM-SOA. This technique has potential applications for integration of wireless and wired services for in-building networks.

We propose and demonstrate, for the first time, service multicasting by all-optical routing of 1 Gb/s IR-UWB using XGM of SOA. This technique has potential applications for integrating IR-UWB with WDM PON and in-building networks.

Radio-over-fibre systems can efficiently deliver broadband wireless services in access and in-building networks. RoF signal transport and routing techniques are presented which are robust against fibre dispersion and provide capacity-on-demand for high-capacity multi-tone radio signals.