The solution to increasingly congested Wi-Fi networks in dense urban areas lies primarily in middle-band spectrum, particularly in the 5.9 GHz band and potentially the 6 GHz band, said Wi-Fi Alliance CEO Ed Figueroa Wednesday. Having 80 MHz and 160 MHz channels is paramount, but that kind of channelization is tough to find in low bands, while high-frequency bands carry propagation limitations, he said at a Microsoft/New America’s Wireless Future Project panel.

With space primed to get more crowded with non-geostationary orbit (NGSO) satellite traffic, satellite operators and regulators increasingly will contend with collision and spectrum interference issues, experts said in interviews. A chief problem is that conjunction warnings to operators about possible collisions will go up exponentially due to that traffic, making it tougher to determine which possible collisions are the most likely and need addressing, said Secure World Foundation Program Planning Director Brian Weeden.

The FCC would slow launch of the 3.5 GHz Citizens Broadband Radio Service if it rewrites the rules for the band now, said Michael Calabrese, director of the Wireless Future Program at New America, in a meeting with Erin McGrath, aide to commissioner Mike O’Rielly. O’Rielly said last week he was asked by Chairman Ajit Pai to take charge of a review and restructuring of the rules (see 1703160029). Since the days after the November election, FCC Republicans have been expected to push forward changes to the rules (see 1611180037). O’Rielly has said the rules for the priority access licensees (PAL), the licensed component of the service, didn’t offer wireless companies enough certainty to ensure a successful PAL auction. Calabrese said in a filing Tuesday in docket 12-354 he counseled against reopening the rules on the geographic size, renewability or duration of the PALs: “Revisiting such basic aspects of the Order, which was adopted on a 5-0 vote nearly three years ago (with Recons on this same issue resolved nearly a year ago), would create uncertainty and tremendous delay on a historic policy innovation to promote spectrum sharing and access for a wide array of users and uses.” Calabrese backed FCC action on the vacant channel NPRM: “I reiterated the strong support of the Public Interest Spectrum Coalition (PISC) for the Commission’s still-pending proposal to preserve at least one vacant television channel in every market nationwide for unlicensed use. Leading chipmakers and other tech industry stakeholders have steadfastly maintained that the post- auction band plan and repacking policies must ensure at least three channels of 6 megahertz of unlicensed access in every market nationwide, especially in the most populated metro markets, to enable many emerging unlicensed use cases."

Higher Ground (HG) doesn't understand possible interference issues arising from its planned satellite earth station network for various broadband applications, with its "deficiencies in the relevant physics and engineering" putting fixed services (FS) at risk, said the Fixed Wireless Communications Coalition in an FCC International Bureau filing Tuesday. FWCC said HG's promise to comply with out-of-band emissions limits -- in response to concerns raised about adjacent channel interference -- is "troubling" since those are different problems. The coalition said HG assertions that low signal strength and small likelihood of proximity to an FS station means low risk of adjacent channel interference have no analysis to back them up. It said HG shows deficient technical understanding when it tries to argue there won't be interference from unwanted reflections in the environment. The filing responded to an HG ex parte filing earlier this month on meetings between CEO Rob Reis and International, Wireless, Public Safety and Homeland Security bureau and Office of Engineering & Technology representatives about FCC authorization of its earth stations and the subsequent opposition (see 1702100055). The firm argued the earth station transmit power levels will be a hundredth of point-to-point microwave stations' and that its software will let an earth station transmit only if its emissions are at least 6 dB below thermal noise at an FS receiver in line of sight. The Tri-State Generation and Transmission Association in filings Monday (see here, here and here) said it opposed HG's use of 5925-6425 MHz band, which it said could interfere with 6 GHz microwave paths. HG outside counsel Adam Krinsky of Wilkinson Barker -- echoing language in HG's consolidated opposition to the applications for review filed by FWCC, Enterprise Wireless Alliance, Utilities Technology Council and APCO -- emailed us Tuesday that the FCC, after more than 18 months of dialogue with the company and numerous demonstrations, concluded its interference protection regime "provides necessary safeguards against harmful interference and granted Higher Ground’s application. The applications for review are based on ‘what if’ speculation, they don’t provide any technical analysis or support, and they disregard the Order’s finding.” FWCC in a reply Tuesday said the only proof HG's system will prevent interference comes from the firm's statements. With no one ever before having done unilateral coordination of mobile transmitters among fixed receivers, "the stakes here warrant the Commission asking for more in the way of assurance than a further repetition of HG's own claims," FWCC said.

The FCC announced a pleading cycle on AT&T’s proposal to fold into its portfolio all of FiberTower’s 24 and 39 GHz licenses. AT&T said in a Jan. 31 blog post it plans to buy all of closely held FiberTower (see 1702010035) and some of the high-frequency spectrum AT&T will need for 5G. “Pursuant to a stock purchase agreement, AT&T Mobility would acquire all of the outstanding stock of FiberTower Corporation, after which FiberTower Corporation would become a wholly-owned subsidiary of AT&T Mobility,” the public notice confirmed. “The Applicants assert that the proposed transaction would serve the public interest by facilitating AT&T’s adoption of 5G technology, which, they claim, would benefit consumers by enhancing existing services and enabling the provision of new ones,” the FCC said. “The Applicants further assert that the proposed transfer of control does not raise spectrum aggregation or competitive concerns.” The agency said by its calculations, AT&T would get 7.2-796.8 MHz of 39 GHz spectrum “in 3165 counties in all or parts of 727 Cellular Market Areas.” Petitions to deny are due March 30, oppositions April 6, replies April 13.

The FCC should preserve at least three TV channels in every market consistent with the vacant channel NPRM, said Michael Calabrese, director of the Wireless Future Program at New America, in a meeting with Rachel Bender, aide to Chairman Ajit Pai. “An early Commission decision is needed to relieve the longstanding uncertainty about whether a minimum of at least three channels of unlicensed spectrum in the ongoing TV band will continue to be available for public use and private investment after the incentive auction,” Calabrese said, according to a Tuesday filing in docket 12-354. “Leading chipmakers and other tech industry stakeholders have steadfastly maintained that the post-auction band plan and repacking policies must ensure at least three channels of 6 megahertz of unlicensed access in every market nationwide, especially in the most populated metro markets, to enable many emerging unlicensed use cases.” Calabrese also made the case for rechannelizing the 5.9 GHz band to separate Wi-Fi from auto safety spectrum: Segmenting the band -- with exclusive public safety use at the top and shared commercial access on a co-equal basis below -- is the only win-win outcome."

Global efforts at spectrum harmonization alternately came under fire and were held up for applause by speakers Tuesday at Satellite 2017. The 2015 World Radiocommunication Conference raised questions about whether there's a fundamental breakdown of the ability to harmonize, said Dynamic Spectrum Alliance President Kalpak Gude. GSMA Senior Spectrum Adviser Veena Rawat said harmonization "is not dead." She said one constant issue with harmonization is the long period that can come between allocation of spectrum for a service and the actual rollout of those services in that band. She cited 600 MHz harmonization through the ITU in 2009, with countries today still transitioning their broadcasting.

The Wi-Fi Alliance raised concerns about an Amtrak waiver request to let the passenger rail service operate at higher power levels in the 5 GHz band than allowed by FCC rules. In December, Amtrak asked the FCC to change the rules under which its Wi-Fi network operates so it can offer more robust service along its key Northeast Corridor (see 1612220013). Amtrak said limits in the UNII-1 band, output power of 250 mW with antenna gain up to 6 dBi, would mean it would have to spend more on stations than if it were allowed to operate at higher power levels. In effect, it asked to operate at levels allowed for fixed point-to-point operations, even though its trains move from place to place. “Wi-Fi Alliance applauds Amtrak for recognizing Wi-Fi as a key component of service to its customers,” the alliance said in a filing in docket 16-415. “However, Amtrak should demonstrate that the benefit its customers will receive will not impose a cost on other users of the 5 GHz band. Wi-Fi Alliance therefore requests that the Commission require Amtrak to provide further evidence of compatibility with other 5 GHz operations before the Commission grants the requested waiver.” An IEEE committee raised similar concerns. “Amtrak has provided no technical details regarding their network, no simulation results or measured data, and no characterization of the environment,” said IEEE 802, which oversees local area and metropolitan area networks. “With no information we cannot begin to understand its impact on neighboring Wi-Fi networks.” Globalstar said that after the request was filed it commissioned a study by Roberson and Associates and asked Amtrak officials questions. “Based on its analysis and these discussions, Globalstar does not object to the Commission’s grant of Amtrak’s waiver request given its very limited deployment and unique design, as long as such grant is narrowly tailored and includes all of the conditions proposed by Amtrak in its request,” Globalstar wrote.

FCC staff took many actions in Chairman Tom Wheeler's last three weeks in office, including some that were controversial, despite Republican pressure to act by consensus during the transition to President Donald Trump. Then-Commissioner Ajit Pai warned in December about "midnight regulations." He and fellow Republican Mike O'Rielly objected to several items issued in January -- a Wireless Bureau report criticizing AT&T and Verizon zero rated data practices, and certain Media Bureau broadcast orders -- and they indicated the issues would be revisited in a GOP-run commission.

Electric utilities wanting to upgrade or expand their microwave radio networks often find all the 6 GHz channels already are assigned, requiring them to buy expensive gigahertz band repeaters, even while the 6 GHz band isn't affected by rain and the 11 GHz one is susceptible to rain fade, said engineering firm Burns & McDowell. The firm's comments, posted Wednesday in RM-11778, supported a Fixed Wireless Communications Coalition petition for changes in earth station licensing (see 1610180035). A microwave path seeking a coordinated pair of frequencies can take up to 24 months for approval and construction, but satellite earth stations can "dynamically change frequencies on the fly without coordination," the firm said.