Ligado, Iridium Intesify Disagreement Over Interference Analysis

Iridium relies on "more invective than fact" in its latest filing in the back-and-forth between it and Ligado over possible Ligado broadband terrestrial network interference to Iridium's mobile satellite service (MSS), Ligado said in a statement Tuesday. Iridium, in a docket 11-109 filing Monday, said Ligado's attacks (see 1701170053) on Iridium's claims of a significant interference risk (see 1612140061) said it used methodologies "widely endorsed by industry and the FCC," while Ligado is misusing FCC ancillary terrestrial component (ATC) rules to try to dodge its obligations to protect MSS providers. Spectrum management principles and FCC rules make clear Ligado must mitigate any ATC interference to MSS operations, Iridium said. It said its analysis shows it's not viable to have terrestrial and satellite services in adjacent spectrum, with potential growth of either coming at the cost of the other, and without an agreement from Ligado to modify its ATC proposal to avoid interfering with Iridium in the adjacent band, the FCC should deny Ligado's ask to convert its 1627.5-1637.5 MHz operations to a terrestrial wireless broadband service. Ligado in its statement said the filing "ignores the substantial compromise that Ligado has put on the table, and suggests that this is more about competitive advantage than spectrum policy. Given that Iridium has twice said it 'does not oppose Ligado’s plans' and other proceedings have successfully shown that satellite and terrestrial can coexist in close proximity, it’s unfortunate that Iridium is not spending its resources discussing those solutions when they are so clearly present."