Summary: | The channel modeling committees of the IEEE 802.15.3 a and 802.15 .4a task groups
devoted considerable effort to developing ultrawideband (UWB) wireless channel
models applicable to systems that operate between 3.1 and 10.6 GHz under both line-ofsight (LOS) and non-line-of-sight (NLOS) conditions in residential, office, outdoor, industrial and body-centric environments at ranges up to 15 m. However, there has been increasing demand for deploying wireless systems in other unconventional environments that have not yet been well characterized. In this thesis, we present four major contributions concerning two such environments: the passenger cabin of a typical midsize airliner and outdoor industrial. First, we have characterized TJWB path gain and
time dispersion over the range 3.1-10.6 GHz within the empty passenger cabin of a
Boeing 737-200 aircraft based on several hundred measured complex channel frequency
responses (CFRs). We found that: (1) the coverage pattern takes the form of chevronshaped contours with path gain decreasing least rapidly along the aisle seats and most rapidly along the window seats, and (2) there is significant advantage to using higher portions of the UWB band for short-range applications and reserving lower portions of the band for longer range applications in such environments. Second, we have characterized the shape of the UWB channel impulse response (CIR) and the fading statistics experienced by individual multipath components (MPCs) over the range 3.1-
10.6 GHz within the Boeing 737-200 aircraft based upon 3300 measured CFRs. We have
also modified the channel simulator developed by IEEE 802.15.4a to generate UWB
CIRs that are representative of those that we observed within the cabin. Third, we have
characterized the effect of human presence on path gain and time dispersion over the
range 3.1-6.1 GHz within the passenger cabin of the Boeing 737-200 aircraft with and
without volunteers in the passenger seats based on a few hundred measured CFRs. We
found that human presence has substantially effects on RF propagation within the aircraft
and that it should be considered when characterizing the performance of in-cabin
wireless systems. Lastly, we present a range-extended VNA-based UWB channel sounder suitable for characterizing UWB propagation in outdoor industrial environments.
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