Woodson agreed to the deal earlier in the week, but didn't sign until after passing a physical earlier Friday.
Woodson returned to his original NFL team last season after spending the previous seven years with Green Bay. The 37-year-old Woodson started all 16 games for the Raiders and had one interception, two sacks, three passes defensed, three forced fumbles and two fumble recoveries.
He expressed interest after the season in returning and the Raiders also wanted him back, leading to another one-year deal.
''At this age, being 37, everyone is looking for me to have a dramatic drop-off in what I do and at the end of the year they think he probably won't play anymore,'' Woodson said. ''So, I'm just taking it one year at a time. I'll do my best to help this team get over the hump and get back into the playoffs. Once that's done, we'll go from there.''
While Woodson was able to start all 16 games a year after missing nine because of injury in Green Bay and he brought the leadership Oakland was seeking, he was unable to improve the results on the field as the Raiders went 4-12 for a second straight year.
That extended their run of seasons without a winning record or playoff berth to 11, starting late in Woodson's first stint in Oakland.
The Raiders have placed a priority on signing players with a winning pedigree this offseason. Woodson joins new defensive linemen Justin Tuck and LaMarr Woodley and returning safety Usama Young as Raiders with Super Bowl titles in their careers. New cornerback Tarell Brown and defensive lineman Antonio Smith have played in Super Bowls previously.
''I think they are good moves,'' Woodson said. ''I think you are bringing in some experience and then I think you fill some other holes with some youth and you have that combination of the two, and I think that we'll be really good this year.''
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