The Gunners slumped to a 2-0 home defeat by Manchester City on Sunday which saw them lose further ground on the top four of the Premier League.
Wenger insists Arsenal are in the market to bolster their squad during the January transfer window, but will only do so if they can find the right quality of player.
The Gunners have been linked with a string of players across Europe, with Lyon playmaker Yoann Gourcuff and West Ham midfielder Mohamed Diame the latest rumoured to be on Wenger's radar, while a new contract for Theo Walcott is expected to be pushed through shortly.
With the club set to see new commercial deals kick in following their £390million move to Emirates Stadium and with plenty of cash in reserve, resources which were further boosted by last summer's sale of captain Robin van Persie to Manchester United, Wenger insists Arsenal will be able to invest heavily in the playing staff.
"My plan is to keep all of the players we have and then to add maybe, if possible, two new players to the squad. We will spend big (again) because we had restricted finances because we had built the stadium and had to pay that back," Wenger said in an interview with Al Jazeera Sport recorded before the City defeat and broadcast on Talksport this morning.
"You look at any club who has done that, and they have gone down (in performance). We stayed at the top level, yes without winning the Premier League, but we were always at the top level.
"Now we have come out in a much stronger position financial again, so we can spend.
"But our way is a bit like Barcelona as well, to produce the core of the team from inside and add from outside the players who give really a plus."
Wenger accepts Arsenal will always be an easy target for those who claim the board put the balance sheet ahead of success on the pitch.
"The biggest challenge so far is to convince people we have a good team, that we have good quality and that we lead the club in the right way, because many people doubt that," Wenger continued.
"I am convinced this team has a fantastic mentality, fantastic quality and with the right level of confidence, if we can create the momentum, we can be a positive surprise until the end of the season."
Wenger may have transformed the fortunes of the Gunners since taking over at Highbury in September 1996, but the Frenchman accepts his time will soon "be up" as the club must one day look for new leadership.
"It is (time up), because I am 63 years old and will not work at 100. That, though, is not the most important, what is important is that when you are somewhere, you give your best," said Wenger, whose side host Swansea in their FA Cup third-round replay on Wednesday night. "How long will I stay? I have a contract until 2014, and I always respected my contracts.
"It is important is that the club goes the right direction - we have a very young team who have fantastic qualities and [it is important] that I help them to get their qualities transformed into positive results.
"Let's not forget that last year we finished third [in the Premier League], as long as that is seen as a disaster, it is not too bad for the future of the club."