Abstract: The stringent reliability and latency requirements of industrial networks are challenged by harsh propagation environments. To design effective communication systems, a thorough understanding of the underlying channel characteristics is essential. Deploying multiple, spatially distributed Access Points (APs) is a promising strategy to overcome these challenges by creating resilient communication links through macro-diversity. This paper presents an experimental characterization of a multi-AP radio channel in a representative industrial laboratory environment, focusing on the 6 GHz band (upper FR1), enabling the investigation of frequency-dependent propagation mechanisms beyond traditional sub-6 GHz cellular bands. We analyze key statistical properties, including inter-link correlation, coherence distance, and coherence bandwidth, to assess the potential for both macro- and micro-diversity. The results demonstrate that the channels from distributed APs are largely uncorrelated, highlighting a significant opportunity for macro-diversity. Conversely, the measured coherence distances far exceed typical device dimensions, suggesting limited returns from single-device spatial diversity. An evaluation of selection combining, equal-gain combining, and maximal-ratio combining techniques confirms that distributed APs can provide substantial diversity gains, ranging from 2.6 dB to 23.1 dB. These findings validate the deployment of coordinated, distributed AP architectures as a crucial strategy for achieving robust, low-latency connectivity in future industrial settings.

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