Pedro, 25, had been training with the Cumbrians and impressed in reserve games against Barrow and Burnley.
The Angola-born wide-man has spent much of his career in the Dutch league with teams such as Feyenoord and Heracles, plus stints in Bulgaria and Romania.
"We've seen enough to know that he adds something different to the group," said head of recruitment Lee Dykes.
He told the club website: "This is a chance for him to show everyone what he can do."
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Carlisle United have signed free-agent winger Louis Pedro on a short-term contract that will expire on 21 May.