Apple is working on a 5G-enabled iPad with mmWave support, according to DigiTimes (a subscription is required to read the entire article).
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mmWave (millimeter wave spectrum) is the band of spectrum between 30 GHz and 300 GHz. Wedged between microwave and infrared waves, this spectrum can be used for high-speed wireless communications. Another part of the spectrum that’s being used in 5G is sub-6 GHz, which includes the portion of spectrum lower than 6 GHz. These bands are effective at providing coverage and have capacity for a wide range of uses.
Chances the rumor is true, according to the Sellers Research Group (that’s me): 90%. Apple is almost certainly working on 5G-enabled iPhones with mmWave support, so such features on an iPad Pro would seem to be a no-brainer.