The team didn't announce the move nor did it send out a notice to the media, but the transaction was listed on the Raiders' website.
Troupe was released by Tampa Bay last week when Jeremy Stevens was activated from the suspended list. A former second-round pick of Tennessee, Troupe has 106 career receptions for 1,056 yards and seven touchdowns.
He was most recently with Tampa Bay, having signed with the Bucs as a free agent in the offseason. But Troupe didn't have a pass in the first two games and was let go when Stevens became eligible.
The Raiders have been seeking help at the position because defenses have been focusing much of their attention of taking Miller out of the passing game. Though he leads the Raiders with six catches, Miller has been forced to stay in to help pass block because of the leaky protection up front.
"With our other tight ends we don't necessarily have a dominant blocker," head coach Lane Kiffin said earlier this week. "They're more pass-receiving type guys. As far as numbers and catches, (Miller) has hurt himself a little bit that way because he's so good that we use him so much in protection."
Madsen played in Oakland's season-opener against Denver but did not catch a pass. He was inactive the following game against Kansas City.
A wide receiver in college who was converted to tight end by the Raiders in 2006, Madsen had played in 31 games with four starts and caught 19 passes for 248 yards and two touchdowns during his two-plus seasons in Oakland.
Raiders sign tight end Troupe
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