Technical Field
The present disclosure relates to the field of NFC communications, and in particular to a method of routing, in a mobile device, NFC messages from an external NFC device to a target host.
Description of the Related Art
Mobile telephones and other types of mobile devices are increasingly being equipped with NFC (Near-Field-Communication) interfaces, which enable them to perform electromagnetic transponder functions in addition to their other functions. In particular, such devices are able to emulate the functions of an electromagnetic transponder, which could be of the contactless card type, or the contactless reader type. Such functionality for example enhances the mobile device, by allowing it to be used for various applications, for example as an electronic wallet allowing payments to be made for accessing services such as transport networks.
To emulate the operation of a contactless card, the mobile device is generally equipped with a contactless front-end integrated circuit (CLF), also called an NFC router. This router is equipped with a radio frequency (RF) transceiver front-end coupled to a low-range antenna to match the communication capabilities of an electromagnetic transponder. In some applications, a secure element, either integrated in the mobile device or contained in a micro-circuit of the subscriber identification module (SIM) or universal SIM, can be used to provide authentication.
NFC communications using a mobile device generally fall within one of three main modes of operation: tag emulation, in which the behavior of a certain type of wireless transponder is emulated by the mobile device; peer-to-peer communications, also referred to as P2P, in which bilateral communications are provided between the mobile device and another device; and reader/writer mode, also referred to as PCD (proximity coupling device), in which the mobile device reads tags by emitting an electromagnetic field.