Financial terms were not released.
The 6-foot-2, 190-pound DeCoud has spent his entire six-year NFL career with the Atlanta Falcons and went to the Pro Bowl in 2012. He has started 78 of his last 79 games, including 15 last year when he registered 83 tackles and returned a fumble 30 yards for a touchdown.
''Thomas provides a veteran in the secondary who is familiar with the NFC South and has been a very solid player,'' Panthers coach Ron Rivera said in a press release. ''We are pleased to add him to a safety group that has good experience and production.''
It's unclear what DeCoud's arrival will mean for safety Charles Godfrey, who missed 14 games last season with a torn Achilles tendon. The Panthers could save more than $5 million if the release the veteran safety - meaningful money for a team that doesn't have much room to maneuver under the NFL salary cap.
Plus, the Panthers already signed free-agent safety Roman Harper from the New Orleans Saints earlier this offseason.
DeCoud was a third-round draft pick of the Falcons in 2009 and has played in 89 games with 507 career tackles, 14 interceptions, three sacks, four forced fumbles and three fumble recoveries. He has played in five playoff games, starting four.
Like DeCoud, Dickson is also a former third-round draft pick who has played his entire career with one team.
The 6-foot-4, 255-pound Dickson started 44 games and played in 60 during his four seasons with the Baltimore Ravens. He has 111 career receptions for 1,178 yards and seven touchdowns since joining the league in 2010.
Dickson also brings plenty of playoff experience to Carolina.
He has played in eight playoff games with five starts and helped the Ravens win the Super Bowl two years ago.
''Ed is a young player who has shown he is a capable blocker as well as receiver in the league,'' Rivera said in a release. ''He provides experienced depth at the tight end position and we look forward to having him in the mix.''
Greg Olsen has been the team's starting tight end for the last three seasons and is expected to remain the team's go-to guy in short-yardage situations. But Dickson offers a nice complement for quarterback Cam Newton as the Panthers look to refocus on their running game this season.
Dickson's best season came in 2011 when he started 16 games and caught 54 passes for 528 yards with five touchdowns.
Last season he started 14 games for the Ravens and caught 25 catches for 273 yards and one touchdown.
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