Systems and methods to support node mobility in wireless networks

Abstract

A network includes a mobile network node (MNN) that includes a mobile node communications manager (MNCM) to facilitate wireless communications to a plurality of stationary network nodes (SNNs) in a wireless network via a wireless network protocol. The MNCM utilizes a multicast address received over the wireless network. The multicast address is assigned to a predetermined network time slot to communicate uplink data from the MNN to the SNNs. The MNN receives downlink data via a separate predetermined network address and time slot assigned to a given SNN.

What is claimed is: 
     
         1 . A device comprising:
 a transceiver configured to communicate via a wireless network; and   a processor configured to:
 receive, via the wireless network, a multicast address, wherein the multicast address is assigned to a first network time slot and addresses a plurality of nodes of the wireless network, 
 transmit uplink data to the plurality of nodes using the multicast address during the first network time slot, and 
 receive first downlink data from a first node of the plurality of nodes via a first address separate from the multicast address during a second network time slot different from the first network time slot, and 
 receive second downlink data from a second node of the plurality of nodes via a second address separate from the multicast address and different from the first address during a third network time slot different from the first network time slot. 
   
     
     
         2 . The device of  claim 1 , wherein the processor is configured to receive acknowledgements from the first and second nodes in response to the uplink data transmitted. 
     
     
         3 . The device of  claim 2 , wherein the processor is configured to receive the acknowledgements from the first and second nodes in a predetermined order. 
     
     
         4 . The device of  claim 1 , wherein the processor is configured to discard the second downlink data in response to the second downlink data being a duplicate of the first downlink data. 
     
     
         5 . The device of  claim 1 , wherein the second and third network time slots are dedicated time slots of a network frame for communicating over the wireless network. 
     
     
         6 . The device of  claim 1 , wherein the processor is configured to adjust a time clock based on a average amount of time drift that the device is from the first and second nodes. 
     
     
         7 . The device of  claim 1 , wherein the processor is configured to adjust a time clock based on a maximum amount of time drift that the device is from the first and second nodes. 
     
     
         8 . The device of  claim 1 , wherein the processor is configured to receive the first and second downlink data over a time slotted channel hopping (TSCH) protocol over the wireless network. 
     
     
         9 . The device of  claim 1 , wherein the multicast address and the first network time slot are assigned prior to the device joining the wireless network. 
     
     
         10 . The device of  claim 1 , wherein the multicast address and the first network time slot are assigned in response to the device joining the wireless network. 
     
     
         11 . The device of  claim 1 , wherein the first and second addresses and the second and third network time slots are assigned prior to the device joining the wireless network. 
     
     
         12 . The device of  claim 1 , wherein the first and second addresses and the second and third network time slots are assigned in response to the device joining the wireless network. 
     
     
         13 . The device of  claim 1 , wherein the processor is configured to, after transmitting the uplink data to the plurality of nodes using the multicast address, retransmit the uplink data to the plurality of nodes using the multicast address. 
     
     
         14 . The device of  claim 1 , wherein the device is a mobile robot. 
     
     
         15 . A method comprising:
 receiving, by a device and via a wireless network, a multicast address, wherein the multicast address is assigned to a first network time slot and addresses a plurality of nodes of the wireless network;   transmitting uplink data to the plurality of nodes using the multicast address during the first network time slot;   receiving first downlink data from a first node of the plurality of nodes via a first address separate from the multicast address during a second network time slot different from the first network time slot; and   receiving second downlink data from a second node of the plurality of nodes via a second address separate from the multicast address and different from the first address during a third network time slot different from the first network time slot.   
     
     
         16 . The method of  claim 15 , further comprising receiving, in a predetermined order, acknowledgements from the first and second nodes in response to the uplink data transmitted. 
     
     
         17 . The method of  claim 15 , further comprising, discarding the second downlink data in response to the second downlink data being a duplicate of the first downlink data. 
     
     
         18 . The method of  claim 15 , wherein the multicast address and the first network time slot are assigned prior to the device joining the wireless network or in response to the device joining the wireless network. 
     
     
         19 . The method of  claim 15 , wherein the first and second addresses and the second and third network time slots are assigned prior to the device joining the wireless network or in response to the device joining the wireless network. 
     
     
         20 . The method of  claim 15 , further comprising, after transmitting the uplink data to the plurality of nodes using the multicast address, retransmitting the uplink data to the plurality of nodes using the multicast address.