IEEE PHOTONICS TECHNOLOGY LETTERS, VOL. 24, NO. 8, APRIL 15, 2012 649 Energy-Autonomous Picocell Remote Antenna Unit for Radio-Over-Fiber System Using the Multiservices Concept Christophe Lethien, David Wake, Bernard Verbeke, Jean-Pierre Vilcot, Christophe Loyez, Malek Zegaoui, Nathan Gomes, Nathalie Rolland, and Paul-Alain Rolland Abstract— The study reported in this letter deals with the extension of the multiservices concept to radio-over-fiber sys- tems with energy-autonomous picocell remote antenna units. Continuous-power, radio-frequency, and digital signals have been combined in a single multimode fiber for the first time. The results clearly demonstrate no impairment of the optically powered remote antenna unit compared to an electrically powered version. The proposed system complies with the classical baseband Ethernet high-data-rate network (10 GbE – bit error rate 10 -12 ). The measured error vector magnitude for the radio-frequency (IEEE802.11g) signal transmission through the designed system stays around 2%, including both the optical transmission over 100-m OM3 multimode fiber and a wireless coverage of 5 m. Index Terms— Energy-autonomous access point, multimode fiber, radio-over-fiber (ROF), 10 GbE, wavelength multiplexing, zero-power devices. I. I NTRODUCTION T HE aim of this study is to propose a multi-services system based on glass multimode fiber and wavelength multi- plexing devices. As the bandwidth capacities of multimode fibers is not fully exploited in the case of a classical home network, we propose to use the same fiber distribution system for a fixed IP/Ethernet digital signal and a radio frequency (RF) wireless signal. Additionally, the wireless access points used to process the RF signal are supplied by optical means, ie through the distribution fiber, which means they do not Manuscript received October 20, 2011; revised December 23, 2011; accepted January 10, 2012. Date of publication January 23, 2012; date of current version March 28, 2012. This work was supported in part by the European Regional Development Fund (ERDF) and in part by the Nord-Pas- de-Calais Region, France, under the CPER CIA Fund. C. Lethien is with the History of Science Department, Institut d’Electronique, de Microélectronique et de Nanotechnologie (IEMN)-IRCICA, Villeneuve d’Ascq 59652, France (e-mail: christophe.lethien@iemn.univ-lille1.fr). D. Wake and N. Gomes are with the Department of Electronics, Broadband and Wireless Communications Group, University of Kent, Canterbury CT2 7NT, U.K. (e-mail: d.wake@kent.ac.uk; n.j.gomes@kent.ac.uk). B. Verbeke, J.-P. Vilcot, C. Loyez, M. Zegaoui, N. Rolland, and P.-A. Rolland are with IEMN, UMR 8520, Université des Sciences et Technologies de Lille, Villeneuve d’Ascq 59652, France, and also with the Research Federation IRCICA USR 3380, Villeneuve d’Ascq 59652, France (e-mail: bernard.verbeke@iemn.univ-lille1.fr; jean- pierre.vilcot@iemn.univ-lille1.fr; christophe.loyez@iemn.univ-lille1.fr; malek.zegaoui@iemn.univ-lille1.fr; nathalie.rolland@iemn.univ-lille1.fr; Paul-Alain.Rolland@IEMN.Univ-Lille1.fr). Color versions of one or more of the figures in this letter are available online at http://ieeexplore.ieee.org. Digital Object Identifier 10.1109/LPT.2012.2185224 need any electrical power supply. With the reported topology based on energy autonomous Remote Antenna Units (RAUs), link cost is reduced owing to additional radio over fiber deployment. The energy autonomy of wireless devices is a key issue to get a self sufficient wireless network. Energy harvesting is a potential solution to supply wireless systems with ambient energy such as solar, vibration, thermoelectricity [1, 2]. In the field of picocell radio over fiber systems, the power consumption (∼250 mW) of a RAU [3] is relatively high to achieve the bidirectional communication with electronic components (amplifier, laser, photodiodes) only powered by some harvesting sources (100 μW). Primary or secondary batteries have to be charged or replaced, leading to a human maintenance on the picocell access points. To reach a zero power radio over fiber network where the RAUs do not integrate either coin, battery or energy harvesting devices, the developed concept proposed in this Letter is to distribute the required power by optical fiber. A high power laser, localized in the central office, is used to distribute optical power through a fiber network to supply RAUs which incorporate a passive fiber pigtailed photovoltaic converter (fig. 1). In each RAU, the optical power is converted to the electrical domain and is used to supply a laser, a photodiode and a RF amplifier, to be able to achieve the wireless communication. In [4], the RF and the power signals are transmitted respectively on singlemode and multimode fibers. Wake et al [3, 5] have developed a radio over multimode fiber system which included an optically powered RAU. A dual transmission over a single multimode fiber has already been reported [6]. In this letter, three types of signal (digital, RF and con- tinuous power) have been transmitted through one single glass multimode fiber (GMMF – 50/125 μm – 100m length – OM3 type – downlink) using coarse wavelength division multiplexing (CWDM) devices. To the best of the authors’ knowledge, such a topology is reported for the first time leading to an energy autonomous picocell RAU. The proposed concept is an evolution of the recent works published in [7, 8] where the simultaneous transmission of digital and RF signals (IEEE 802.11g) on a single OM4 glass multimode fiber is studied. The first part of this Letter describes the methodology and the design of an energy autonomous remote antenna unit (RAU). The last part of this Letter reports on a comparative study between electrically and optically powered RAU; spectrum masks and error vector magnitude (EVM) 1041–1135/$31.00 © 2012 IEEE