Trimble featured twice in last year's Six Nations - in the wins over Italy and England - and admits he is looking for more game time this time around after securing his domestic future.
"We have some big games coming up, so I am happy I was able to agree my new contract before we went into the busy period," Trimble said.
"Our game this weekend against Biarritz is my first priority.
"I want to play well with Ulster and challenge for an Ireland place in the Six Nations and the World Cup."
And Trimble wasn't the only one in the Irish set up pleased he had signed a new contract; with head coach Declan Kidney also expressing his satisfaction at the deal.
"It is important for the provinces and Ireland to keep as many of our top players playing here," Kidney said.