Rapper T.I. performs in Atlanta Sunday May 24, 2009. The Grammy-winning rapper is to report by noon Tuesday to the Federal Correction Institution at Forrest City, Ark., to serve a a sentence for federal weapons conviction. [Agencies]

ATLANTA – Rapper T.I. gave his fans a rousing send-off before he heads to prison on a federal weapons conviction.

The Grammy-winning rapper told the audience at a Sunday night concert in Atlanta's Philips Arena that he would stay optimistic while serving his sentence for a year and a day.

"I'm going to stand up tall, head up high," he said. "Thank you for all of your support."

Many in the packed crowd of about 16,000 people held up encouraging signs, like one reading "T.I. We Will Miss U!"

The 28-year-old rapper, whose real name is Clifford J. Harris Jr., must report by noon Tuesday to the Federal Correction Institution at Forrest City, Ark.

He was arrested after prosecutors said he tried to buy unregistered machine guns and silencers from undercover federal agents in 2007.

During the concert, T.I. said he hoped that everyone learned from his mistakes. He brought his five children on stage to stand next to him, often holding one of them while he performed "No Matter What" — a single off the almost double-platinum album "Paper Trail."

T.I., who won a Grammy for "Swagga Like Us," also performed all his hits from "What You Know" to "Bring 'Em Out" to his recent chart-topping singles "What Ever You Like" and "Live Your Life." Teenage rapper Soulja Boy also joined him on stage.

"What I need y'all to do is pray for me while I'm gone," he said. "I'll see y'all in 366 days."