There is a growing interest in detecting and processing Global Navigation Satellite System (GNSS) signals in indoors and urban\r\ncanyons by handheld devices. To overcome the signal attenuation problem in such adverse fading environments, long coherent\r\nintegration is normally used. Moving the antenna arbitrarily while collecting signals is generally avoided as it temporally decorrelates\r\nthe signals and limits the coherent integration gain. This decorrelation is a function of the antenna displacement and geometry\r\nof reflectors and angle of arrival of the received signal. Hence, to have an optimum receiver processing strategy it is crucial to\r\ncharacterize the multipath fading channel parameters. Herein, Angle of Arrival (AoA) and Angle Spread (AS) along with signal\r\nspatial correlation coefficient and fading intensity in GNSSmultipath indoor channels are defined and quantified theoretically and\r\npractically. A synthetic uniform circular array utilizing a right-hand circular polarized (RHCP) antenna has been used to measure\r\nthe spatial characteristics of indoor GNSS fading channels. Furthermore, rotating effect of a circular polarized antenna on the\r\nsynthetic array processing and AoA estimation has been characterized. The performance of the beamforming technique via array\r\ngain is also assessed to explore the advantages and limitations of beamforming in fading conditions.
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