Tyfone Inc. has received a patent for its system that enables people to use removable memory cards to add payments capabilities to their mobile phones.

The patent, entitled "Electronic Transaction Card," was announced Monday by the Portland, Ore., technology company.

The Tyfone system incorporates near-field communication chips into memory cards that can be installed in phones that lack built-in NFC components.

Numerous payments companies have tested NFC chips that are built into phones, but such phones are not yet widely available. NFC chips function like contactless payment cards.

Tyfone said it completed a test of its u4ia (pronounced "euphoria") mobile payments technology in June.