The Ravens confirmed the new deals on their official Twitter feed. Terms of the agreements were not immediately released.
Now that the initial free-agent frenzy is over, most teams are focused on plugging the remaining holes on their roster. Brown and Carter represent depth signings for the Ravens.
Brown played an extremely limited role within the offense last season. He made 14 catches for 112 yards and no touchdowns across 10 games, including two starts.
There was an opportunity for him to step up after Steve Smith Sr. suffered a season-ending Achilles injury midway through the campaign. He failed to capitalize, as Mike Clay of SiriusXM showcased using Pro Football Focus grades:
Mike Clay @MikeClayNFL
PFF ranking among 121 qualified WR last year: 6 Steve Smith 19 Kamar Aiken 72 Jeremy Butler 79 Chris Givens 96 Mike Wallace 120 Marlon Brown2016-3-15 18:38:53
Typically in that type of situation, both the player and the team decide it's best to go their separate ways. But the Ravens must believe the best is yet to come for the 24-year-old, 6'5'' wideout.
He'll serve in a depth role once again. Smith is expecting to play once Week 1 rolls around, assuming his recovery continues at a steady pace. Baltimore also added fellow deep threat Mike Wallace on Tuesday to upgrade the receiving group.
The 26-year-old linebacker split last season between Cincinnati and Baltimore. He didn't register any stats in two games with the Ravens.
He'll likely spend training camp battling for a spot on the final roster as a depth linebacker and special teams contributor.
These aren't the type of signings that are going to whip the fanbase into a frenzy, of course. But they help fill out the roster with players who already have experience with the franchise.
They should provide reasonable reserve value for the Ravens next season. The team just has to hope they aren't thrust into high-profile roles due to a rash of injuries.