We present a review of physical networking options and enabling system technologies for efficient unification of optical and wireless access backhaul infrastructure. Different physical layer integration architectures are reviewed in conjunction with the possible wireless signal transport schemes. We also review some of our research work as one possible physical layer integration technique using RF-overlay passive optical network incorporating an optical tandem single sideband (OTSSB) modulation scheme for simultaneous transport of wired and wireless signals.
High-speed card-to-card optical interconnects are highly demanded in high-performance computing and data centers. Compared with other solutions, free-space optical interconnects have the capability of providing both reconfigurability and flexibility. In this paper we propose and experimentally demonstrate a free-space based reconfigurable optical interconnect architecture and it is capable of connecting cards located both inside the same rack as well as in different racks. Results show that 3×10 Gb/s data transmission is achieved with a worst-case receiver sensitivity better than -9.38 dBm.
In this paper a novel high bandwidth optical wireless communication system for indoor personal area networking
applications with both ubiquitous coverage and mobility feature is proposed and tradeoffs are studied. Gigabit-per-second
optical wireless communication system with limited mobility provided to users has been demonstrated by proof-of-
concept experiments for the first time. It has also been shown that when incorporating with the WiFi-based
localization system, our proposed system can provide high-speed error-free operation with mobility over the entire room.
Radio-over-Fiber (RoF) systems have been actively researched to provide future wireless broadband services. In this
paper we review the schemes and strategies that have been carried out in Radio-over-Fiber networks over the years to
realize high-performance RoF links.
Hybrid fiber-wireless networks for fixed wireless access operating in the millimeter-wave wave (mm-wave) frequency
region have been actively pursued to provide untethered connectivity to ultra-high bandwidth communications. The
architecture of such radio networks requires a large number of antenna base stations with high throughput to be deployed
to maximize the geographical coverage with main switching and routing functionalities located in a centralized location.
The transportation of mm-wave wireless signals within the hybrid network is subject to low opto-electronic conversion
efficiency, fiber chromatic dispersion and also signal degradation due to nonlinearity along the link. One of the major
technical challenges in implementing such networks lies in the mitigation of the various optical impairments that the
wireless signals experience within the hybrid network. In this paper, we present an overview of the different techniques
and schemes to overcome some of the signal impairments in transporting mm-wave radio signals over optical networks.
We study the impact of Amplified Spontaneous Emission (ASE) noise on a Semiconductor Optical Amplifier (SOA)-based optical pulse delay discriminator and SOA-based distance ranger. Our experiments show that ASE reduces the sensitivity of these SOA-based devices and we confirm this finding by carrying out extensive simulations by modeling the ASE response of SOAs. The simulation results, obtained by numerical integration of these equations in MATLAB<sup>TM</sup> using the NIMROD<sup>TM</sup> portal, are in qualitative agreement with experimental results.
Broadband wireless access operating in the microwave and millimeter-wave frequency windows has been actively investigated for future ultra broadband communications. The drastic increase in the throughout of each base station in these systems necessitates the use of an optical fiber backbone to provide broadband interconnections between the central office and all the antenna base stations. With such a network layout, significant reduction of the antenna base station complexity can be achieved by moving the routing, switching and processing functionalities to the central office. By taking advantage of optical networking techniques such as wavelength division multiplexing (WDM), the total capacity of the hybrid fiber-wireless network can be greatly enhanced and efficient optical fiber architectures can be realized. In this paper we present an overview of the research that has been carried out in fiber-wireless networks incorporating WDM, with a particular focus on the optical interfaces in such networks.