Patent ID: 8488581

Claim:
A method of conducting a financial transaction via radio frequency communications, the method comprising: operating a host computer, the host computer having an application program for controlling an interrogator, the host computer configured to: cause the transmission of a first wireless command from the interrogator to initiate identification of one of a population 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 the population; cause the interrogator to receive a first reply from the one radio frequency communications device in response to the first wireless command; cause the transmission of a second wireless command from the interrogator to initiate identification of one of a subpopulation of at least one radio frequency communications device, the second wireless command including second bits that are configured to elicit one or more responses from the subpopulation; cause the interrogator to receive a second reply from the one radio frequency communications device in response to the second wireless command; cause the identification of the identifier of the one radio frequency communications device when there is no collision in response to the second wireless command; and cause the transmission of a third wireless command to individually identify the one radio frequency communications device using the identifier of the one radio frequency communications device, the third wireless command requesting the one radio frequency communications device to transmit a subsequent reply; and cause the debiting of an account associated with the one radio frequency communications device based at least in part on at least a portion of the replies from the one radio frequency communications device.