Ligado Suggests Lower Power Limits to Protect Aviation GPS

Ligado -- facing pushback from certified aviation GPS interests about possible interference from its terrestrial low-power broadband service (TLPS) (see 1805160009, 1709260048 and 1708070025) -- is pledging new power limits on its use of the 1526-1536 MHz band to protect those GPS receivers. A docket 11-109 filing Thursday amended its modification applications to set equivalent isotropically radiated power limits on its ancillary terrestrial component base stations and to require that its ATC base stations can't operate in that band near an FAA-established obstacle clearance surface. That should "fully protect" certified aviation GPS receivers, it said, adding those protections are consistent with issues brought up in Transportation Department test results on adjacent-band compatibility to GPS (see 1805160009). The company will take mitigation steps that include upgrading or replacing government devices as a fix to concerns about potential effects on U.S. government devices, "and expects a requirement." It said if the FCC approves its TLPS plans, it will invest as much as $800 million on its satellite and terrestrial network. Competitive Carriers Association President Steve Berry in a statement said the group agrees with Ligado "that mid-band spectrum offers important opportunities for deploying next generation technologies," and the FCC should "make as much spectrum available as possible for commercial use. ... The overwhelming consumer demand for wireless connectivity and next generation technologies including 5G have made it more important than ever for the FCC to look at every opportunity to free up additional spectrum where possible." The National Coordination Office for Space-Based Positioning, Navigation and Timing didn't immediately comment.