Aalto University Schools of Technology - electronic academic dissertations - http://otalib.aalto.fi/fi/kokoelmat_tiedonhaku/e-julkaisut/vaitoskirjat/
Dissertation for the degree of Doctor of Science in Technology to be presented with due permission for public examination and debate in Auditorium S1 at Helsinki University of Technology (Espoo, Finland) on the 2nd of March 2001 at 12 o'clock noon.
Overview in PDF format (ISBN 951-22-5372-0) [541 KB]
Dissertation is also available in print (ISBN 951-22-5354-2)
This thesis discusses the development of micro- and millimeterwave wideband radio channel measurement and modeling techniques for future radio networks. Characterization of the radio channel is needed for radio system, wireless network, and antenna design. A radio channel measurement system was designed for 2.154, 5.3 GHz and 60 GHz center frequencies, and completed at the two lower frequencies. The sounder uses a pseudonoise code in the transmitter. In the receiver, first a sliding correlator, and later direct digital sampling, where the impulse response is detected by digital post processing, were realized. Certain implementation questions, like link budget, effects of phase noise on impulse response and direction of arrival estimation, and achievable performance using the designed concept, are discussed.
Measurement campaigns included in this thesis were realized at 5.3 GHz frequency in micro- and picocells. A comprehensive measurement campaign performed inside different buildings was thoroughly analyzed. Propagation mechanisms were studied and empirical models for both large scale fading and multipath propagation were developed. Propagation through walls, diffraction through doorways, and propagation paths outside the building were observed. Pathloss in LOS was lower than the free space pathloss, due to wave guiding effects. In NLOS situation difference in the pathloss models in different buildings was significant. Behavior of the spatial diversity was estimated on the basis of spatial correlation functions extracted from the measurement data; an antenna separation of a fraction of a wavelength gives sufficient de-correlation for significant diversity gain in indoor environments at 5.3 GHz in NLOS.
This thesis consists of an overview and of the following 7 publications:
Keywords: radio channel sounder, indoor radio channel, wideband correlator, radio channel modeling
This publication is copyrighted. You may download, display and print it for Your own personal use. Commercial use is prohibited.
© 2001 Helsinki University of Technology