Overview
The 3GPP B1 (2100 MHz) LTE band is the sixth most popular band used by public mobile operators for LTE network deployments, and is typically deployed due to the existing regulatory framework in place governing 2100 MHz spectrum, as well as the ability for operators to refarm unused spectrum allotments for 4G. 2100 MHz band 1 spectrum provides a good compromise between capacity/density and penetration/range.
Mobile carriers have flexibility to deploy LTE using band 1 as a single band or as part of a multi-band network, with reportedly over 50 mobile networks deployed (April 2018). LTE-A or LTE-Advanced Pro technologies can be deployed using carrier aggregation to combine various bandwidths of band 1 with other carriers.