Tech subcommittee to hold hearing on LightSquared

He questioned why the FCC allowed LightSquared to get as far as it has in the regulatory process before discovering the interference problems, but he suggested there could still be an engineering solution to the interference problem.

He noted that the interference is a result of GPS devices receiving signals from outside of their designated frequencies — not by LightSquared's signal bleeding into the GPS band. He said he hopes it would be possible for GPS companies to modify their receivers to work in the presence of LightSquared's network.

Walden said his hearing will probe why the FCC did not discover the interference problem earlier and what can be done about it now.

Sen. Chuck GrassleyCharles (Chuck) Ernest GrassleyPavlich: The claim Trump let the mentally ill get guns is a lie Congress fails miserably: For Asian-Americans, immigration proposals are personal attacks Grassley, Dems step up battle over judicial nominees MORE (R-Iowa) has pledged to block President Obama's two nominees to fill FCC vacancies unless the agency releases internal documents related to its review of LightSquared.

The company is financed in large part by billionaire Phil Falcone of Harbinger Capital. But the company is now reportedly running low on cash and risks losing a contract with Sprint unless it can receive regulatory approval in the coming weeks.