1 Department of Photonics Engineering, Technical University of Denmark2 Coding and Visual Communication, Department of Photonics Engineering, Technical University of Denmark3 Metro-Access and Short Range Systems, Department of Photonics Engineering, Technical University of Denmark
In this Ph.D. project, design and performance evaluation of mm-wave radio over fiber links for diverse applications including video transmission are conducted. Major objective of this Thesis is to study performance of video and data signals transmitted in radio over fiber (RoF) setups with a constraint on complexity. For wireless personal area networks distribution, we explore the notion of joint optimization of physical layer parameters of a fiber-wireless link (optical power levels, wireless transmission distance) and the codec parameters (quantization, error-resilience tools) based on the peak signal-to-noise ratio as an objective video quality metric for compressed video transmission. Furthermore, we experimentally demonstrate uncompressed 1080i highdefinition video distribution in V-band (50–75 GHz) and W-band (75–110 GHz) fiber-wireless links achieving 3 m of wireless transmission in both cases. For the W-band, experimental assessment of passive and active approaches for implementation of base stations is included, and the channel coding use is assessed. Use of millimeter-wave signals in metropolitan mobile backhaul is also considered in this Thesis. We propose a setup enabling efficient wired/wireless backhaul of picocell networks. Gigabit signal transmission is realized in combined fiber-wireless-fiber link enabling simultaneous backhaul of dense metropolitan and suburban areas. In this Thesis, we propose a technique to combat periodic chromatic dispersion-induced radio frequency (RF) power fading in a simple intensity modulation-direct detection mm-wave RoF link through introduction of a degree of frequency tunability at the RoF transmitter. We study advanced RoF infrastructures to better suit video transmission. To enable efficient dynamic multicast/broadcast of video services, we have proposed and evaluated an approach of increasing the functionality of the optical remote node by including the wireless channel replication and allocation. Another approach for multicast of RF signals - delivering multiple simultaneously upconverted lightwaves from the central office to designated BSs is evaluated for diverse lightwave generation and data modulation techniques. Mm-wave RoF links employing various lightwave generation techniques are experimentally demonstrated for diversified fiber infractructure including standard single mode fiber, multimode fiber and dispersion shifted fiber in order to estimate the feasibility of mm-wave wireless video services’ delivery through fiber infrastructure with different nonlinear impairments and dispersion.
Main Research Area:
Vegas Olmos, Juan José, Forchhammer, Søren, Tafur Monroy, Idelfonso