GPS industry group denies responsibility for interference issues

By Brendan Sasso - 08/17/11 05:03 PM ET

Global Positioning System device makers fired back at wireless startup LightSquared in a filing with the Federal Communications Commission on Monday, claiming they are not responsible for interference problems between their devices and LightSquared’s planned network.

Last week, LightSquared sent a letter to the FCC pinning the blame for the interference issues on GPS makers for failing to follow appropriate standards in designing their receivers.

But in its most recent filing, the U.S. GPS Industry Council accused LightSquared of misrepresenting the technical issues causing the interference.

“LightSquared is wrong, and its arguments reflect its fundamental lack of technical understanding of GPS and the profound technical difference between how communication and satellite navigation signals operate and are received,” the GPSIC wrote.

LightSquared had accused GPS makers of not following Defense Department standards in designing their receivers, but the GPSIC noted that the Defense Department standards apply to military, not commercial, receivers.

“[LightSquared’s] August 11 Letter changes nothing, and must be rejected as just another flawed effort on LightSquared’s part to deflect attention from the technical and regulatory inappropriateness of introducing 4G LTE service into the 1525-1559 MHz and 1626.5-1660.5 MHz bands,” the GPSIC wrote, referring to the sections of spectrum that LightSquared plans to use for its nationwide broadband network.

In its own FCC filing on Monday, LightSquared said the GPS industry should have addressed potential interference concerns 10 years ago, when LightSquared’s predecessor company first proposed the network.

The company has agreed to use its land-based network on only the lower half of its spectrum in an effort to minimize problems.

Additionally, LightSquared has offered to pay for research and development into new technologies to prevent its network from affecting GPS devices.

GPS is considered critical to public safety because it is used by emergency responders, airplane navigators and the military.