班娜 transliterates Western female names like Banna, Bana, and occasionally Banya. The
娜 (nà) suffix is one of the standard phonetic markers for foreign female names ending in -na/-nah:
安娜 (Anna),
戴安娜 (Diana),
苏珊娜 (Susanna).
班 (bān) phonetically picks up the bann- syllable.