The FCC has invited public comment on a Petition for Rule Making (RM-11715) that would make a significant portion of the 10.0 to 10.5 GHz band available for wireless broadband services. The Petition by Mimosa Networks Inc proposes a band plan for 10.0 to 10.5 GHz that, it says, would protect frequencies most often used by radio amateurs. The petition hinges on FCC adoption of rule changes that would put the 10 GHz band under Subpart Z of the Commission’s Part 90 rules. Subpart Z currently sets out regulations governing wireless licensing, technical standards, and operational standards in the 3650 to 3700 MHz band.

“[T]he application of the coordination procedures and requirements provided in Subpart Z will ensure that Amateur Radio operations in the band will not be disrupted,” Mimosa told the FCC. “In addition, as a further safeguard, Mimosa proposes a band plan for the 10.0-10.5 GHz band that would protect frequencies in the band that are most often used by Amateur Radio operators.” The proposed band plan would specify 10.350 to 10.370 GHz as an “Amateur Calling Band,” and 10.450 to 10.500 GHz for Amateur-Satellite operations in the midst of 21 wireless broadband channels and a small guard band.

Mimosa has proposed to include in the rules a requirement for wireless broadband service operation in the band “to avoid harmful interference with Amateur service and Amateur-Satellite service operations in the band.”

In the international Table of Frequency Allocations, the primary allocation in Region 2 (the Americas) is to Radiolocation. Amateur Radio is secondary in the entire band, while Amateur-Satellite is secondary at 10.450 to 10.500 GHz. In ITU Regions 1 and 3, the Fixed Service is co-primary; two “country footnotes” — essentially exceptions that individual countries have carved out in the allocations table — provide for primary Fixed and Mobile allocations in named countries, however. While these include Mexico and several other Region 2 countries, the US and Canada are not among them. Mimosa asserted in its Petition that including 10.0-10.5 GHz under Subpart Z “would bring ITU Region 2 into alignment with Regions 1 and 3.”

“In Mimosa’s view, the coordination procedures and requirements provided in Subpart Z will ensure that Amateur Radio operators will be able to continue using the 10.0-10.5 GHz band as they do currently,” the company told the FCC, “without any disruption of their activities resulting from the Commission’s making the band available for wireless broadband services.”

Mimosa contended that its proposal would “promote the Commission’s goal of providing broadband access to all Americans, would benefit wireless Internet service providers, mobile wireless carriers, and telecommunications equipment providers, and would benefit the national economy.” Mimosa cited the band’s “long-reach, high-capacity characteristics” and called 10 GHz “a promising candidate for wireless broadband.”

ARRL Chief Executive Officer David Sumner, K1ZZ, said that while the League appreciates Mimosa’s efforts to acknowledge existing and growing 10 GHz Amateur Radio activity, several aspects of the petition are of concern.

“Use of the band for fixed or mobile wireless broadband would be contrary to the international Table of Frequency Allocations and would inject a new sharing consideration that is not contemplated in the preparatory work being done for World Radiocommunication Conference 2015 (WRC-15),” he said. “Mimosa’s proposed power limit of 55 dBW EIRP is very high, particularly for point-to-multipoint operations, and no mechanism has been proposed for ensuring that harmful interference to amateur operations does not occur.”

Sumner said that while the ARRL has not yet adopted a position with respect to the petition, “some aspects of the petition require careful study.”

Interested parties may comment on RM-11715 using the FCC’s Electronic Comment Filing System (ECFS).