A Practical Approach to Generating First-Order Rician Channel Statistics in a RC plus CATR Chamber at mmWave

Abstract

This paper investigates utilizing a hybrid configuration that merges a Reverberation Chamber (RC) with a Compact Antenna Test Range (CATR) to achieve a controllable K-factor for testing directive antennas. The focus has been on the lower frequency bands of FR2 (24.25-29.5 GHz). The study encompasses a thorough evaluation of 39 unique configurations. A stationary horn antenna is consistently employed throughout the investigation for reference K-factor characterization, with considerations such as integrating absorbers, attenuators, and varied CATR polarizations. An examination of the signal-to-noise ratio reveals that the samples consistently maintain a substantial margin above the noise level, demonstrating independence across all cases. The Bootstrap Anderson-Darling goodness-of-fit test is employed to meticulously assess conformity to Rician and/or Rayleigh distributions, yielding results that closely align with anticipated outcomes. The analysis encompasses crucial parameters, including total received power, stirred power, unstirred power, and K-factor, with an additional exploration into frequencydependent modeling. Notably, total received, stirred, and unstirred powers exhibit an inverse relationship with frequency, while the K-factor does not demonstrate a clear frequencydependent pattern. Fitted models effectively capture frequency variability for stirred power but fall short in elucidating K-factor trends. A noteworthy insight emerges when utilizing CATR signal co-polarized with the horn antenna, resulting in heightened K-factors, reduced system losses, and improved frequency stability.