Timing re-synchronization with reduced communication energy in frequency hopping communication networks

A method, comprising:

• discovering, by a main-powered communication device, a low duty cycle, periodic, quick-sample schedule of a battery-operated communication device within a frequency hopping sequence in a communication network;
• transmitting, during a scheduled sample, a control packet from the main-powered communication device to the battery-operated communication device, the control packet containing timing information, the control packet transmitted by the main-powered communication device to account for worst-case clock drift error between the battery-operated communication device and the main-powered communication device;
• receiving, in response to the control packet, a link-layer acknowledgment at the main-powered communication device, the acknowledgment containing timing information from the battery-operated communication device;
• and
• re-synchronizing timing between the battery-operated communication device and the main-powered communication device at the main-powered communication device based on the timing information in the acknowledgment.

An apparatus, comprising:

• a processor;
• a battery power supply;
• a transceiver configured to communicate in a communication network according to a frequency hopping sequence;
• and
• a memory configured to store a process executable by the processor, the process when executed by the processor operable to:
• quick-sample the frequency hopping sequence at a periodic rate corresponding to a substantially low duty cycle;
• receive, during a sample, a control packet from a main-powered communication device, the control packet containing timing information, the control packet transmitted by the main-powered communication device to account for worst-case clock drift error between the apparatus and the main-powered communication device;
• respond to the control packet with a link-layer acknowledgment to the main-powered communication device, the acknowledgment containing timing information from the apparatus;
• and
• re-synchronize timing between the apparatus and the main-powered communication device based on the timing information in the control packet.

An apparatus, comprising:

• a processor;
• a main-power power supply;
• a transceiver configured to communicate in a communication network according to a frequency hopping sequence;
• and
• a memory configured to store a process executable by the processor, the process when executed by the processor operable to:
• discover a low duty cycle, periodic, quick-sample schedule of a battery-operated communication device;
• transmit, during a scheduled sample, a control packet to the battery-operated communication device, the control packet containing timing information, the control packet transmitted to account for worst-case clock drift error between the battery-operated communication device and the apparatus;
• receive, in response to the control packet, a link-layer acknowledgment containing timing information from the battery-operated communication device;
• and
• re-synchronize timing between the battery-operated communication device and the apparatus based on the timing information in the acknowledgment.