Striker signs until January from Leeds to join brother Stephen in blue
The move to Portman Road see the Republic of Ireland international, who trained with his new team-mates for the first time this morning, reunited with his brother, Stephen.
Noel joined Reading in the summer of 2008, with his older sibling already at the club and they were team-mates for a year.
The 31-year-old striker had spells at Dunfermline and Dundee United, where he scored 28 goals in 75 appearances, before heading to the Madejski.
He spent five years with the Royals, scoring 39 goals in 162 appearances and helped the club win the Championship title in 2012 alongside another current Blue, Jay Tabb.
A year later he joined his former Reading boss Brian McDermott at Leeds.
Born in Waterford, Noel has been capped three times by Ireland at senior level and he will wear the number 16 shirt during his time at Portman Road.