Patent ID: 7346061

Claim:
A method of commencing near-field wireless communications between an initiator device and a target device, comprising the steps of: detecting, by the initiator, a presence of a radio frequency(RF) field; transmitting a first electromagnetic wave to the target, the electromagnetic wave configured to carry a request at a first transmission rate selected from a plurality of transmission rates when an RF field is not detected within a time period defined by T IDT +n×T RFW , where T IDT is an initial delay time, n is a random number, and T RFW is an RF waiting time to start one of either an active and a passive mode of communication; and initiating communication between the initiator and the target in one of the active mode and the passive mode of communication, wherein when in the active communication mode, the target performs the steps of detecting a presence of a radio frequency(RF) field, transmitting a response to the initiator by transmitting a second electromagnetic wave from the target when the RF field is not detected in said detecting step within a time period defined by T ADT +n×T RFW , where T ADT is an active delay time, n is a random number, and T IDT >T ADT , wherein when in the passive communication mode, the target performs the step of sending a response to the initiator energized from the first electromagnetic wave received from the initiator, said sending step including performing load modulation.