Malekizandi, Mohammadreza (2018)
Generation and Transmission of Optical Ultra-wideband Signals for Optical Fiber and Wireless Communication Links.
Technische Universität Darmstadt
Dissertation, Erstveröffentlichung
Kurzbeschreibung (Abstract)
The demand for high bandwidth in wireless communication in the past years has been growing rapidly as the personal smart devices are becoming more and more an inseparable part of modern life. Accordingly, the current wireless personal area network (WPAN) has to migrate to a higher radio frequency in order to satisfy the demand for high data rates. Ultrawideband (UWB) systems are considered to be one of the most promising technologies for short range broadband wireless communication, due to their numerous attractive features such as low power spectral density, wide bandwidth, enhanced ability for penetrating obstacles , immunity to multi-path fading, coexistence with other wireless systems and capability of providing Gbps data transmission. In the year 2002, the U.S. Federal Communications Commission approved the unlicensed use of the UWB spectrum from 3.1 GHz to 10.6 GHz, with a power spectral density lower than -41.3 dBm/MHz. Due to the low power spectral density, the wireless coverage of UWB technology is limited to a few meters, while the broadband access technology demands a larger coverage in range of kilometers. In order to satisfy this demand and also integrate the local UWB environment into the fixed wired network, UWB-over-fiber (UWBoF) is proposed as a promising solution. The concept of UWBoF is to transmit the UWB signals over optical channels in order to extend the coverage area and benefit from the features offered by the optical fiber such as, low loss and immunity to electromagnetic interference. Moreover, generating and encoding the UWB signals directly into the optical domain is highly desirable, in order to avoid the use of wideband electronics and the need for extra optical-electrical conversion. Furthermore, optical generation of UWB signals has many other advantages such as light weight, small size and large tunability. This dissertation proposes a novel concept on the optical generation of UWB pulses. In particular, the ultimate goal is to introduce a technique which satisfies the demands of the future fiber optic based WPAN industry such as: simplicity in transmitters and receivers, low cost, the most effective utilization of the imposed FCC mask, ability to deliver high data rates (range of Gbps), offering a huge coverage area (range of 10s of kilometers), compatibility with the time-division-multiplexing passive-optical-networks (TDM-PONs) and compatibility with the wavelength-division-multiplexing passive-optical-networks (WDM-PONs). Accordingly, a simple and cost effective approach based on the direct modulation of a semiconductor laser and optical filtering is investigated and experimentally demonstrated. The novel pulse shaping techniques are reported and their compliance to the FCC mask in terms of bandwidth, spectral power efficiency and wireless coverage is studied. The impact of the fiber transmission on the generated UWB signals based on the proposed technique is investigated and a coverage area of up to 60 km is experimentally verified. The compatibility of the transmitter with the TDM-PON is demonstrated through the generation and error-free transmission of a 1.25-Gbps UWB signal and a 10-Gbps-non-return-to-zero (NRZ) signal with the use of only one single light source and in different time slots of a TDM architecture. Additionally, the performance evaluation of a bidirectional, symmetric and WDM-compatible transmission of 1.25 Gbps UWB over 60 km fiber is performed and error-free transmission is obtained. Finally, transmission of a 2.5 Gbps UWB signal is made possible by employing a new modulation technique in the transmitter. The outstanding achievements of this thesis underline the great potential of UWBoF for the future of smart, cost effective, energy efficient and broadband WPAN applications.
Typ des Eintrags: | Dissertation | ||||
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Erschienen: | 2018 | ||||
Autor(en): | Malekizandi, Mohammadreza | ||||
Art des Eintrags: | Erstveröffentlichung | ||||
Titel: | Generation and Transmission of Optical Ultra-wideband Signals for Optical Fiber and Wireless Communication Links | ||||
Sprache: | Englisch | ||||
Referenten: | Küppers, Prof. Dr. Franko ; Berroth, Prof. Dr. Manfred | ||||
Publikationsjahr: | Juli 2018 | ||||
Ort: | Darmstadt | ||||
Datum der mündlichen Prüfung: | 21 Juni 2018 | ||||
URL / URN: | http://tuprints.ulb.tu-darmstadt.de/7522 | ||||
Kurzbeschreibung (Abstract): | The demand for high bandwidth in wireless communication in the past years has been growing rapidly as the personal smart devices are becoming more and more an inseparable part of modern life. Accordingly, the current wireless personal area network (WPAN) has to migrate to a higher radio frequency in order to satisfy the demand for high data rates. Ultrawideband (UWB) systems are considered to be one of the most promising technologies for short range broadband wireless communication, due to their numerous attractive features such as low power spectral density, wide bandwidth, enhanced ability for penetrating obstacles , immunity to multi-path fading, coexistence with other wireless systems and capability of providing Gbps data transmission. In the year 2002, the U.S. Federal Communications Commission approved the unlicensed use of the UWB spectrum from 3.1 GHz to 10.6 GHz, with a power spectral density lower than -41.3 dBm/MHz. Due to the low power spectral density, the wireless coverage of UWB technology is limited to a few meters, while the broadband access technology demands a larger coverage in range of kilometers. In order to satisfy this demand and also integrate the local UWB environment into the fixed wired network, UWB-over-fiber (UWBoF) is proposed as a promising solution. The concept of UWBoF is to transmit the UWB signals over optical channels in order to extend the coverage area and benefit from the features offered by the optical fiber such as, low loss and immunity to electromagnetic interference. Moreover, generating and encoding the UWB signals directly into the optical domain is highly desirable, in order to avoid the use of wideband electronics and the need for extra optical-electrical conversion. Furthermore, optical generation of UWB signals has many other advantages such as light weight, small size and large tunability. This dissertation proposes a novel concept on the optical generation of UWB pulses. In particular, the ultimate goal is to introduce a technique which satisfies the demands of the future fiber optic based WPAN industry such as: simplicity in transmitters and receivers, low cost, the most effective utilization of the imposed FCC mask, ability to deliver high data rates (range of Gbps), offering a huge coverage area (range of 10s of kilometers), compatibility with the time-division-multiplexing passive-optical-networks (TDM-PONs) and compatibility with the wavelength-division-multiplexing passive-optical-networks (WDM-PONs). Accordingly, a simple and cost effective approach based on the direct modulation of a semiconductor laser and optical filtering is investigated and experimentally demonstrated. The novel pulse shaping techniques are reported and their compliance to the FCC mask in terms of bandwidth, spectral power efficiency and wireless coverage is studied. The impact of the fiber transmission on the generated UWB signals based on the proposed technique is investigated and a coverage area of up to 60 km is experimentally verified. The compatibility of the transmitter with the TDM-PON is demonstrated through the generation and error-free transmission of a 1.25-Gbps UWB signal and a 10-Gbps-non-return-to-zero (NRZ) signal with the use of only one single light source and in different time slots of a TDM architecture. Additionally, the performance evaluation of a bidirectional, symmetric and WDM-compatible transmission of 1.25 Gbps UWB over 60 km fiber is performed and error-free transmission is obtained. Finally, transmission of a 2.5 Gbps UWB signal is made possible by employing a new modulation technique in the transmitter. The outstanding achievements of this thesis underline the great potential of UWBoF for the future of smart, cost effective, energy efficient and broadband WPAN applications. |
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Alternatives oder übersetztes Abstract: |
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URN: | urn:nbn:de:tuda-tuprints-75220 | ||||
Sachgruppe der Dewey Dezimalklassifikatin (DDC): | 600 Technik, Medizin, angewandte Wissenschaften > 620 Ingenieurwissenschaften und Maschinenbau | ||||
Fachbereich(e)/-gebiet(e): | 18 Fachbereich Elektrotechnik und Informationstechnik 18 Fachbereich Elektrotechnik und Informationstechnik > Institut für Mikrowellentechnik und Photonik (IMP) > Photonik und Optische Nachrichtentechnik 18 Fachbereich Elektrotechnik und Informationstechnik > Institut für Mikrowellentechnik und Photonik (IMP) |
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Hinterlegungsdatum: | 22 Jul 2018 19:55 | ||||
Letzte Änderung: | 22 Jul 2018 19:55 | ||||
PPN: | |||||
Referenten: | Küppers, Prof. Dr. Franko ; Berroth, Prof. Dr. Manfred | ||||
Datum der mündlichen Prüfung / Verteidigung / mdl. Prüfung: | 21 Juni 2018 | ||||
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