Why? Microwave bands are limited in capacity, particularly in countries and bands where spectrum is limited due to congestion. Even if you can get additional frequencies, scaling capacity means aggregating multiple channels that results in high equipment costs and potentially expensive recurring spectrum fees. E-Band alone is not sufficient either. With more bandwidth available that enables higher capacities, E-Band suffers from a number of potential limitations, from short link distances and high susceptibility to rain outage and pole/tower sway to difficult and time-consuming installation/antenna alignment.