LightSquared is on the defensive following a conference call yesterday hosted by the Coalition to Save Our GPS that outlined the group's objections to LightSquared's proposed dual terrestrial and satellite broadband network.

LightSquared said, "The FCC is requiring [it] to build a massive terrestrial network that reaches 260 million Americans by the end of 2015."

The Coalition to Save Our GPS has argued that LightSquared's proposed network will cause significant expense to both the private sector and the government. The group argues that possible disruptions in GPS services and the necessary technological fixes to alleviate any interference caused by LightSquared's network operating on the L-band, which is immediately adjacent to the band on which GPS runs, could run in the billions of dollars.

The coalition also argued that the FCC never intended for LightSquared's spectrum to be employed as a standalone nationwide network, but rather as a way to fill gaps in coverage. LightSquared told investors that it purchased the spectrum for $2 billion, but the coalition says that if used in the service of a standalone network, the FCC would have to auction the spectrum off, where it would fetch upwards of $12 billion.

"The idea that a New York hedge fund should get a $10 billion windfall at the expense of the taxpayer is just unacceptable," said Jim Kirkland, vice president and general counsel for Trimble, in yesterday's coalition call.

Terry Neal, senior vice president of public relations and communications for LightSquared, argued that, "like many wireless companies, including AT&T and Verizon, LightSquared is investing in spectrum that was licensed to it before the spectrum auction process was put in place."

Additionally, LightSquared referred to an FCC report dated April 6, which states that "extensive terrestrial operations have been anticipated in the L-band for at least eight years."