Not in a lab. I am in a manufacturing production plant where I am about to implement [turn on] the 3702 APs as I mentioned. The HP111's are actually connected to an application for Auto-Guided Vehicles [AGV's].
The 802.11 specs say 802.11ac are backwards compatible with 802.11a radios in the M111's but my worry is, in a real environment with 802.11ac's supporting MIMO and transmitting three spatial streams, and with the older 802.11a radio in the M111's not being MIMO capable, will they stop working because of being overwhelmed by multipath signals?
Or is there something at the data layer that informs the 802.11ac radio not to transmit MIMO when responding? In a multi-device environment, I don't see, or understand anyway, how this would work.
i have a wireless router HP M111 that supports 802.11a for 5Ghz only, it does not have 802.11ac. I am installing a new design with Cisco 3702 APs which have 802.11ac radios. While I know 802.11ac is backward compatible with a, I am wondering if the device might have multipath issues due to the 3 spatial streams coming from the 802.11ac radios?

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