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arXiv · 2610.14890

Directional and Quasi-Omnidirectional Indoor Channel Measurements at Upper 6 GHz

Chengsong Fu·Hongbo Zhao·Jianer Zhou·Xiongbin Yu·Weichao Li·Chen Zhuang·Meng Li·Wenquan Feng·Xiaofeng Tao
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Abstract

Physical directional and quasi-omnidirectional antenna pairs are compared at 6.425--7.125 GHz over 32 position-matched indoor links per configuration: 23 line-of-sight (LOS) and nine non-LOS (NLOS) links in an open hall and an L-shaped corridor. Peak-gain normalization retains antenna-pattern weighting in the measured path loss, shadow-fading residuals, RMS delay spread (DS), and PDP-equivalent $K$ factor. Hall LOS close-in exponents are nearly identical at 2.10/2.11 for directional\slash quasi-omnidirectional pairs, yet median DS values differ markedly at 1.78/36.52 ns. Directional DS is lower at all LOS positions, with smaller fitted shadow-fading residuals and higher $K$ factors. Representative PDPs associate these differences with reduced off-axis delayed energy. In corridor NLOS, the directional floating-intercept slope is negative, consistent with distance-dependent antenna-pattern weighting under the fixed pointing rule, whereas the quasi-omnidirectional slope is positive and DS ordering varies by position. These results quantify practical antenna-filtered channels without angular-scan synthesis, with unequal weak-path sensitivity contributing to the observed differences.

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Chengsong Fu, Hongbo Zhao, Jianer Zhou, Xiongbin Yu, Weichao Li, Chen Zhuang, Meng Li, Wenquan Feng, Xiaofeng Tao. 2026-10-10. Directional and Quasi-Omnidirectional Indoor Channel Measurements at Upper 6 GHz. https://arxiv.org/abs/2610.14890

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