Rambis said that Fredette, a former lottery pick, is expected to be signed Monday.
"Between now and then a lot of things can happen, so I anticipate that that's what's going to happen and we've just got to try and integrate him and see if we can use him in some way," Rambis said. "He's obviously a very good shooter and somebody who can open the floor for us, so we'll see how he fits in."
Fredette has played this season with the Knicks' D-League team, the Westchester Knicks. He's averaged 22.3 points and 4.8 assists in 28 games. He also scored a record 35 points to be named the MVP of the D-League All-Star Game last Saturday.
Rambis said the Knicks' coaching staff had monitored Fredette's play via game tape.
"He obviously can shoot the basketball; that's what he's known for," Rambis said. "We've got to see if he can actually handle the basketball and be able to create shots for himself and create shots for others within the team concept, so it will be an adjustment for him.
"It's not going to be an easy transition and guys who are in the D-League ... at that point in time, they're not NBA ballplayers. So it's a different level to make the step up here."
The Knicks (23-33) currently have 14 players under contract, so they do not have to make a corresponding roster move to add Fredette.
Fredette, the 2011 National Player of the Year and NCAA scoring champ out of BYU, hasn't found a steady role in the NBA. He has been with three NBA teams since being selected by the Sacramento Kings with the 10th overall pick in the 2011 draft.
Fredette, 26, has played in 229 games over the past four seasons, averaging 6.1 points in 13 minutes per game.
Asked about Fredette bouncing around the NBA, Rambis said, "Sometimes it takes players a few years to figure out how to adjust to the game and the NBA level, so we'll see if he made those adjustments."