Patent ID: 7620409

Claim:
A wireless system comprising: at least one initiating device; a responding device; wherein the wireless system is configured to perform wireless communication in which: the initiating and responding devices may communicate on more than one channel selected from a list of channels; the responding device intermittently has an interruption in its normal operation to listen for a transmission from an initiating device, each interruption of the responding device is sufficiently long to receive a transmission of at least one message requesting time synchronization information; the initiating device repeatedly sends a transmission of messages on each of two or more channels requesting time synchronization information of the responding device allowing time between transmissions for receiving a response from the responding device; the responding device receives the transmission from the initiating device during an interruption, the responding device remains on the same channel during the interruptions for a selected number of interruptions for receiving a transmission from the initiating device; the initiating device repeatedly sends the transmission messages requesting time synchronization information on channels selected from a series of sequences of channels, for a period of time during and in between a number of interruptions equal to or greater than the selected number of interruptions; each sequence of channels contains all channels from the list of channels in a different permutation; a message requesting time synchronization information is transmitted on each channel from the sequence of channels; each sequence of channels from the series of sequences of channels is used for transmissions of the message requesting time synchronization information such that the message requesting time synchronization information is transmitted on all channels from the list of channels during the selected number of interruptions; and the responding device sends time synchronization information of the responding device to the initiating device following a reception of the transmission from the initiating device.