Patent ID: 8714449

Claim:
A security system comprising: a card including a transponder circuit to transmit data responsive to an energize signal; a contactless card reader for receiving data transmitted by the card, the contactless card reader including a scheduler configured and arranged to generate an output in response to determining that the contactless card reader is to begin transmitting; a controller communications circuit configured and arranged to respond to the output from the scheduler by calculating a transmit start time based upon a number of channels in a frequency-hop table between a current transmitting channel and an expected listening channel of a receiving device and an expected listening time that the receiving device is expected to begin listening on the expected listening channel, and starting a transmission based upon the determined transmit start time; a card energizing circuit for producing the energize signal, a battery circuit for powering the controller communications circuit and the card energizing circuit, and a power-control circuit to control use of the battery circuit in response to card proximity, wherein the contactless card reader is configured to store a log of access requests and to transmit the log of access requests at predetermined intervals that correspond to the output from the scheduler; and a controller that controls arming and disarming of the security system based on data wirelessly transmitted by the communications circuit and wherein the controller is configured and arranged to wirelessly communicate with multiple peripheral devices.