OF DOCTORAL DISSERTATION HELSINKI UNIVERSITY OF TECHNOLOGY P. O. BOX 1000, FI-02015 TKK http://www.tkk.fi Author Tuomo von Lerber Name of the dissertation Applications of fiber optical resonators in measurement and telecommunications technology Date of manuscript April 10, 2007 Date of the final manuscript August 27, 2007 Date of the dissertation October 5, 2007 Monograph Article dissertation (...

Bio-molecular recognition is detected by the unique optical properties of self-assembled gold nanoparticles on the unclad portions of an optical fiber whose surfaces have been modified with a receptor. To enhance the performance of the sensing platform, the sensing element is integrated with a microfluidic chip to reduce sample and reagent volume, to shorten response time and analysis time, as ...

The development of optical fibers has revolutionized telecommunications by enabling long-distance broadband transmission with minimal loss. In turn, the ubiquity of high-quality, low-cost fibers has enabled a number of additional applications, including fiber sensors, fiber lasers, and imaging fiber bundles. Recently, we showed that a multimode optical fiber can also function as a spectrometer ...

This paper presents the effect of dispersion and Multi Access Interference (MAI) of optical fiber on the Bit Error Rate (BER) performance of a Direct Sequence Optical Code Division Multiple Access (DS-OCDMA) network by means of intensity modulation and ORC. By using Mat lab simulations, Signal-toNoise Ratio (SNR) versus Received Optical Power (ROP) of an OCDMA transmission system can be evaluat...

We report simultaneous control of the orbital angular momentum (OAM) and beam profile of vortex beams generated in two-mode polarization-maintaining optical fiber. Two higher-order eigenmodes of the fiber are combined to form optical vortices. Reduced coherence between the fiber modes decreases the mode purity. Varying the coherence of the fiber modes changes the average OAM while maintaining a...

Next generation wireless networks must provide high broadband access, which can be achieved by combining the fiber optics and wireless technologies. In this paper we analyze a mm-wave radio over fiber (RoF) optical access network architecture, combining radio subcarrier multiplexing techniques to improve system efficiency with fiber dispersion mitigation provided by optical single sideband modu...

We have developed a fluorescence-based fiber-optical biosensor, which can selectively detect different antibodies in serial at preselected positions inside a single piece of fiber. The fiber is a microstructured polymer optical fiber fabricated from TOPAS cyclic olefin copolymer, which allows for UV activation of localized sensor layers inside the holes of the fiber. Serial fluorescence-based s...