"I know I will suffer," said the 37-year-old French World Cup winner, whose participation at Ewood Park remains subject to international clearance.
"For the next game it's going to be difficult for me but I am very excited about playing for this club."
Pires was released by Villarreal in July as a free agent having spent four years with the Spanish outfit.
After working on his fitness with the Gunners during the summer, the veteran midfielder, who scored 84 goals in 284 appearances for his former club between 2000 and 2006, is now after more silverware at Villa Park.
Nice to see you signed Pires - an experienced player from France and a good player
"I would love to win a trophy - the Carling Cup or FA Cup. It would be nice to compete for a Champions League place too. I love to have objectives and challenges," stated Pires.
"This move represents a new opportunity and a new challenge for me. I have seen the young players in action because I watched the last game against Manchester United [They drew 2-2].
"There are a lot of injuries at the moment but Villa have some top youngsters. This is very important for the future of the club. The most important thing is having a good mix. That gives you good opportunities to win trophies."
Meanwhile, Aston Villa midfielder Barry Bannan has secured a new three-and-a-half year contract in the same week he made his debut for Scotland against the Faroe Islands.
The 20-year-old is the latest youngster to commit their future at Villa Park, following recent new deals for Marc Albrighton and Ciaran Clark.
Bannan said: "Everything this season has been unbelievable. I could never have imagined it going so well for me. To get the deal is icing on the cake really."
Source: BBC Sport