Hier finden Sie wissenschaftliche Publikationen aus den Fraunhofer-Instituten.

Capacity analysis in indoor wireless infrared communication using adaptive multiple subcarrier transmission

: Grubor, J.; Jungnickel, V.; Langer, K.-D.


Marciniak, M. ; IEEE Lasers and Electro-Optics Society:
7th International Conference on Transparent Optical Networks 2005. Proceedings. Vol.2 : Barcelona, Catalonia, Spain, July 3 - 7, 2005; Collocated with 4th European Symposium on Photonic Crystals, ESPC 2005, July 4 - 5, 4th Workshop on All-Optical Routing, WAOR 2005, July 4 - 5, 2nd Global Optical & Wireless Networking, GOWN 2005, Seminar, July 6, COST 270 Workshop on Reliability Issues in Next Generation Optical Networks, RONEXT 2005, July 4 - 5, Photonic Integrated Components & Applications Workshop, PICAW 2005, July 5, COST 291 Workshop on Issues and Challenges in Optical Networking, July 4 and e-Photon/ONe Special Session, July 6
Piscataway, NJ: IEEE, 2005
ISBN: 0-7803-9236-1
International Conference on Transparent Optical Networks (ICTON) <7, 2005, Barcelona>
European Symposium on Photonic Crystals (ESPC) <4, 2005, Barcelona>
Workshop on All-Optical Routing (WAOR) <4, 2005, Barcelona>
Global Optical and Wireless Networking Seminar (GOWN) <2, 2005, Barcelona>
Workshop on Reliability Issues in Next Generation Optical Networks (RONEXT) <2005, Barcelona>
Photonic Integrated Components and Applications Workshop (PICAW) <2005, Barcelona>
Workshop on Issues and Challenges in Optical Networking <2005, Barcelona>
Fraunhofer HHI ()
adaptive modulation; channel capacity; indoor communication; optical communication; power control; signal processing; telecommunication control

In the research field of indoor wireless IR communications state-of-the-art systems achieve high data rates through angular or spatial diversity. An innovative concept for performance improvement in IR system, based on signal processing and adaptive modulation, is proposed. This technique, known from DSL, and currently under discussion for RF wireless, seems also attractive for IR indoor systems, but needs to be examined under the specific conditions of the wireless optical channel (new problem statement). As first evaluation step, we perform capacity analysis to assess potential data rates in the multi-path IR channel present in most rooms. We derive the optimal power control for IR channels subject to an optical power constraint. Results show that, depending on the channel state, system capacity dramatically varies which can be efficiently exploited only by an adaptive system.