Jewell's side advanced to the second round of the League Cup with a 3-1 win over Bristol Rovers on Tuesday, but he remains frustrated in the transfer market.
"It's been a really frustrating few weeks. We've thought we've had deals tied up and then things have happened. What could have gone wrong has gone wrong but we've just got to be patient," he told Press Association Sport.
Ipswich begin their Championship campaign at home to Blackburn Rovers on Saturday.