Members of AT&T’s technical and regulatory staff met with officials in the FCC’s Wireless Telecommunications Bureau on Thursday to discuss a possible new category of devices operating in the Citizens Broadband Radio Service (CBRS) 3.5 GHz band.
According to an ex parte filing (PDF), the meeting primarily focused on AT&T’s questions about whether the commission would entertain a proposal to increase the power levels for a new category of CBSDs, a term that generally refers to CBRS small cells.
The FCC currently has two categories for CBSDs: Category A refers to a lower power base station and Category B refers to a CBSD that must be deployed outdoors and has higher maximum power limits compared with Category A devices.
According to AT&T’s presentation (PDF), it is advocating a proposal to allow a new Category C CBSD with even higher power, which would allow for “operational, technical flexibility” and enable additional 5G use cases for CBRS as a midband anchor for 5G New Radio (NR).
Specifically, it proposes the addition of a third category with maximum allowable Equivalent Isotropically Radiated Power (EIRP) up to 62 dBm/10 MHz. EIRP refers to the total RF power radiated by the antenna. For Cat A devices, it’s 30 dBm/10 MHz and for Cat B CBRS devices, it’s 47 dBm/10 MHz
Under certain conditions, as determined by the Spectrum Access Controller (SAS), Cat C devices could take advantage of midband propagation characteristics, but AT&T said its proposal would continue to protect incumbents and not impact current SAS certifications.
The proposal comes as the CBRS industry prepares for initial commercial deployments in the General Authorized Access (GAA) portion of the band. The Priority Access License (PAL) portion of the band involves the auctioning of licenses and that’s not expected to happen until next year.