{"id":16427,"date":"2020-04-24T17:00:34","date_gmt":"2020-04-24T17:00:34","guid":{"rendered":"https:\/\/one.sightlinemg.com\/defensenews\/uncategorized\/2020\/04\/24\/recalculating-gps-l-band-and-the-pentagons-untenable-position-on-5g\/"},"modified":"2026-08-08T17:50:46","modified_gmt":"2026-08-08T17:50:46","slug":"recalculating-gps-l-band-and-the-pentagons-untenable-position-on-5g","status":"publish","type":"post","link":"https:\/\/one.sightlinemg.com\/defensenews\/commentary\/2020\/04\/24\/recalculating-gps-l-band-and-the-pentagons-untenable-position-on-5g\/","title":{"rendered":"Recalculating: GPS, L-band and the Pentagon\u2019s untenable position on 5G"},"content":{"rendered":"\n

Last week, Ajit Pai, the chairman of the Federal Communication Commission, submitted the L-band Ligado spectrum proposal for approval, which, he said, will \u201cmake more efficient use of underused spectrum and promote the deployment of 5G\u201d with \u201cstringent conditions to prevent harmful [GPS] interference.\u201d All five FCC commissioners voted<\/a> to affirm the proposal, which was formally published in a 70-page report.<\/p>\n\n\n\n

L-band is a critical piece of spectrum that will help accelerate the deployment of U.S. 5G so we can compete and ultimately win against China. The Department of Defense argues that use of the L-band<\/a> (as Ligado proposes) will interfere with GPS, which is essential to our military and economy.<\/p>\n\n\n\n

The FCC\u2019s final order concludes that the testing upon which the DoD and other opponents based their GPS interference claims was invalid. L-band opponents\u2019 interference measurement (termed 1dB C\/No) is \u201cinappropriate\u201d and \u201cthere is no connection presented in the technical studies\u201d that prove this measure of interference \u201crelates to performance-based metrics\u201d of a GPS receiver.<\/p>\n\n\n\n

In short, the FCC said there is no harmful GPS interference, and opponents have been using a flawed methodology and an invalid test with which the FCC \u201cstrongly disagree[s].\u201d<\/p>\n\n\n\n

The FCC\u2019s recent report is not the first time the Ligado proposal was determined to cause no GPS interference. In early 2019, the National Telecommunications and Information Administration under David Redl reviewed the Ligado proposal carefully \u2014 along with the 20 government agencies that comprise the review body \u2014 and determined there is no interference. The NTIA then wrote a recommendation for approval and, before it could get to the FCC, it was blocked, eventually leading to Redl\u2019s dismissal.<\/p>\n\n\n\t