Patent ID: 8638709

Claim:
A method of conducting a financial transaction via radio frequency communications, the method comprising: transmitting a first wireless command from an interrogator to initiate identification of at least one radio frequency communications device, the first wireless command including first bits that are configured to elicit one or more responses from a population of one or more radio frequency communication devices; receiving a first reply from a radio frequency communications device in response to the first wireless command; transmitting a second wireless command from the interrogator to initiate identification of the radio frequency communications device, the second wireless command including second bits that are configured to elicit one or more responses from a subpopulation of the population; receiving a second reply from the radio frequency communications device in response to the second wireless command; determine at least a portion of identifier of the radio frequency communications device when there is no collision in response to the second wireless command; and causing the debiting of an account associated with the radio frequency communications device based at least in part on at least a portion of the replies from the radio frequency communications device.