Ex-US congressman sentenced to 22 months for insider trading

Stephen Buyer was a Republican from Indiana in the U.S. House of Representatives between 1993 and 2011 .

He was found guilty on four counts of securities fraud at a trial in March .

Buyer bought Sprint stock after learning from a T-Mobile executive that the telecommunications companies were in merger talks.

Prosecutors sought three years in prison for Buyer , saying he had abused clients' trust.