Ligado Challenges GPS Incompatibility Claims

The National Executive Committee for Space-Based Positioning, Navigation and Timing has been painted "a very inaccurate picture of Ligado's current proposal," the company said in a letter to Excom posted Thursday in FCC docket 11-109. The letter from Ligado CEO Doug Smith, plus one from Dennis Roberson of Ligado consultant Roberson and Associates, were in response to a letter to Excom from the chairman of the Space-Based PNT Advisory Board (PNTAB) they said inaccurately said Ligado's LTE plans aren't substantially different from what Ligado as LightSquared previously proposed and which Excom rejected in 2012. The power levels and bands to be utilized are considerably different, Smith said, saying Ligado's plans don't face objections from major GPS companies, unlike the previous iteration of the LTE plan under LightSquared. The PNTAB letter also falsely asserts Ligado's system will be high-power, will include terrestrial use of frequencies just below GPS and will share spectrum with GPS, he said. Roberson said the PNTAB letter about Ligado coexistence with GPS ignores testing Roberson did to demonstrate their compatibility. PNTAB Chairman John Stenbit didn't comment.