A near field communication (NFC) system includes a portable device having an embedded NFC antenna, an add-on module blocking the embedded NFC coil and an NFC transfer coil wrapped around the add-on module to eliminate blocking of the embedded NFC antenna. A predetermined set of NFC antenna tuning parameters is associated with each add-on module and is applied by the device's NFC controller upon identifying the docked add-on module. In an embodiment, the NFC transfer coil includes linked first and second NFC coils which replicate NFC signals in each other. The NFC transfer coil may include a ferrite shield between each of the linked NFC coils and the add-on module to minimize the creation of eddy currents that may degrade the performance of the embedded NFC antenna.