Characterization of the ORBIT Indoor Testbed Radio Environment

We perform a set of measurements of channel frequency responses at different points in the room that accommodates the ORBIT indoor testbed using a vector network analyzer (VNA). To validate the data collected with VNA we use spectrum analyzer (SA) measurements, as well. Four measurements are performed over non-overlapping 100 MHz bands in the industrial, scientific, and medical (ISM) band, and in the unlicensed national information infrastructure (UNII) band. The fifth measurement spans the coarsely sampled .4 to 6 GHz band. From the measured frequency responses we calculate path loss model parameters. The path loss exponent is between 1.1 and 2 and the dynamic range of the signal is around 25 dB across different bands. Based on the frequency responses measured over the .4 to 6 GHz band we determine multipath intensity profiles (MIP) with fine time granularity. The comparison of MIPs to the ray tracing simulations generated with WiSE software indicates that the surfaces perpendicular to the plane defined by the transmit and receive antennas represent a significant source of reflections. However, the reflections from the floor, dropped ceiling, and roof are suppressed by the antenna elevation patterns.