LightSquared Blames GPS Receivers for Spectrum Interference

LightSquared is blaming the GPS industry's failure to comply with the Department of Defense's (DoD) filtering standards for interference issues involving its proposed broadband wireless network. DoD standards issued in September 2008 calls for GPS receivers to filter out transmissions from adjacent bands in order to achieve the performance intended to be provided by the GPS system.


LightSquared said the GPS industry has ignored the DoD standard and spurned international recommendations for GPS receiver design. Whereas the DoD standard grants GPS a 4 MHz "guard band", LightSquared said GPS manufacturers are rejecting its offer of a 23 MHz guard band that would be created by LightSquared's decision to begin its terrestrial operations in the lower half of the downlink band. Instead, the GPS industry is seeking a 34 MHz guard band.


In a letter to the FCC, LightSquared Executive Vice President for Regulatory Affairs & Public Policy Jeffrey Carlisle states: "Had the GPS industry complied with DoD's recommended filtering standards for GPS receivers, there would be no issue with LightSquared's operations in the lower portion of its downlink band... If all spectrum users demanded the irrational guard band solutions that GPS manufacturers are demanding, we would not have broadband in this country and efficient spectrum use would take a backseat to the squeakiest wheel." http://www.LightSquared.com