System and method for data transfer in frequency hopping wireless networks

A method for transferring data in a frequency hopping wireless network between an end device and a coordinator device comprising the steps of:

• a. the coordinator device scanning a plurality of frequencies for request for services messages during a time slot where no data packets are being transferred;
• b. the end device sending a request for services message on a first frequency of the plurality of frequencies, where the request for services message includes a preamble identifiable by the coordinator device;
• c. if the coordinator device detects the request for services message preamble on the first frequency, the coordinator devices receiving the remainder of the request for services message using the first frequency and sending a service packet message to the end device from which it received the request for services message using the first frequency;
• d. if the end device detects the service packet message on the first frequency within a time interval, the end device receiving the service packet message from the coordinator device using the first frequency;
• and
• e. if the end device does not detect the service packet message on the first frequency within the time interval, the end device initiates another attempt to transfer data by sending another request for services message on a second frequency of the plurality of frequencies scanned by the coordinator device.

A frequency hopping wireless network system, the system comprising:

• a coordinator device configured to:
• scan a plurality of frequencies for request for services messages during a time slot where no data packets are being transferred;
• detect a request for service preamble on one of the plurality of frequencies and, responsive thereto, receive the remainder of the request for services message on the one frequency and send a service packet message to an end device from which it received the request for services message on the one frequency, where the service packet message includes:
• i. a current frequency sequence value of the coordinator device's pseudorandom number sequence, and
• ii. beacon timing information that indicates when periodic beacon messages from the coordinator device occur;
• and
• an endpoint device configured to:
• send a request for services message on a first frequency of the plurality of frequencies scanned by the coordinator device, where the request for services message includes a preamble identifiable by the coordinator device;
• receive the service packet message from the coordinator device and, responsive thereto, change the end point's current frequency sequence value and timing information to match the frequency sequence and beacon timing information values sent by the coordinator device in order to synchronize the end device with the coordinator device.