METHOD FOR KEEPING WORKING STATE OF SMART CARD ENTERING FIELD AGAIN, AND SMART CARD

摘要

A method for keeping a working state of a smart card entering a field again, and the smart card. The method comprises: when a smart card is in an electromagnetic field of an electronic device and is activated, send a waiting time extension instruction to an electronic device, the waiting time extension instruction at least comprising a preset waiting duration (S201); after the smart card receives a response to the waiting time extension instruction returned by the electronic device, start a timer, a timing time of the timer being a preset waiting duration (S202); when the smart card detects that the smart card leaves the field, determining whether the timer times out; and if not, keep the current state of the smart card to be an activation state, a built-in power supply of the smart card supplies power to the smart card when the smart card leaves the field (S203); and when the smart card enters the field again, determine whether the timer times out; and if not, keep the current state of the smart card to be an activation state (S204).