Charlie Ergen, chairman of satellite-TV provider Dish Network Corp., made a $2 billion bid for radio frequencies from LightSquared Inc., the bankrupt wireless-broadband company owned by Philip Falcone’s hedge-fund firm, Bloomberg News reported yesterday. Ergen has offered to buy the spectrum even though the Federal Communications Commission has yet to approve its use. Reston, Va.-based LightSquared filed for bankruptcy last year after regulators blocked approval to build its network on concern it would interfere with global-positioning system signals. LightSquared would use the proceeds from selling its airwaves to pay off secured debt, according to the people. The company has until May 31 to accept the offer, which was made May 15.