Johnson, 29, spent the last four seasons in Cincinnati, where he played in all
16 regular-season games each year as a special teamer and reserve linebacker.
The Louisville product registered a career-high 83 tackles in 2008.
Johnson was selected by the Arizona Cardinals in the fifth round of the 2006
The Steelers also signed long snapper Matt Katula, released tight end Wes
Lyons and placed wide receiver Connor Dixon on the waived/injured list.