Wireless communication handover procedure

Abstract

A method includes communicating with a remote device using a first access node of an access network; determining, by a centralized stack node of the access network, that a quality of a first wireless communication link between the remote device and the first access node is below a threshold; identifying a second access node in the access network for which a quality of a second wireless communication link between the remote device and the second access node is above the threshold; responsive to identifying the second access node, updating, by a centralized controller of the stack node, an access node identifier associated with a connection with the remote device to be an identifier for the second access node; and communicating with the remote device using the second access node.

What is claimed is: 
     
         1 . A vehicle comprising:
 a plurality of access nodes including a first access node and a second access node; and   a stack node coupled to the first and second access nodes, the stack node including a stack node controller configured to:
 implement a communication stack to facilitate a connection with a vehicle key; 
 communicate with the vehicle key using a first wireless communication link between the first access node and the vehicle key; and 
 determine that a quality of a second wireless communication link between the second access node and the vehicle key is greater than a quality of the first wireless communication link; and 
 in response to determining that the quality of the second wireless communication link is greater than the quality of the first wireless communication link, communicate with the vehicle key using the second wireless communication link. 
   
     
     
         2 . The vehicle of  claim 1 , wherein communicating with the vehicle key using the second wireless communication link comprises communicating with the vehicle key using the second wireless communication link instead of the first wireless communication link. 
     
     
         3 . The vehicle of  claim 1 , wherein the plurality of access nodes comprises a third access node, wherein the stack node is coupled to the third access node. 
     
     
         4 . The vehicle of  claim 1 , wherein the stack node controller is configured to receive periodic indications of the quality of the second wireless communication link, and wherein determining the quality of the second wireless communication link comprises determining the quality of the second wireless communication link based on the received periodic indications. 
     
     
         5 . The vehicle of  claim 1 , wherein the stack node controller is configured to, in response to determining that the quality of the second wireless communication link is greater than the quality of the first wireless communication link, update an access node identifier to be an identifier for the second access node, wherein the stack node controller is configured to select an access node from the plurality of access nodes for communication with the vehicle key based on the access node identifier. 
     
     
         6 . The vehicle of  claim 5 , wherein the stack node further comprises a memory, and wherein updating an access node identifier comprises updating an access node identifier in a service table stored in the memory. 
     
     
         7 . The vehicle of  claim 5 , wherein the stack node controller is configured to send a transmit command to the access node of the plurality of access nodes specified by the access node identifier. 
     
     
         8 . The vehicle of  claim 5 , wherein the stack node controller is configured to send a receive command to the access node of the plurality of access nodes specified by the access node identifier to instruct the access node of the plurality of access nodes specified by the access node identifier to receive a data packet from the vehicle key and provide such received data packet to the stack node controller. 
     
     
         9 . The vehicle of  claim 1 , wherein an instance of the communication stack used to communicate with the vehicle key using the first access node is the same instance as the communication stack used to communicate with the vehicle key using the second access node. 
     
     
         10 . The vehicle of  claim 1 , wherein the communication stack is a Bluetooth Low Energy (BLE) communication stack, the stack node controller is a BLE controller, and the stack node further comprises a BLE host. 
     
     
         11 . The vehicle of  claim 1 , wherein the communication stack is a Bluetooth Low Energy (BLE) communication stack, wherein the stack node controller is configured to implement a link layer of the BLE communication stack, and wherein the first access node is configured to implement a physical layer of the BLE communication stack. 
     
     
         12 . The vehicle of  claim 1 , wherein determining that the quality of the second wireless communication link is greater than the quality of the first wireless communication link comprises:
 determining that the quality of the first wireless communication link is below a threshold; and   determining that the quality of the second wireless communication link is above the threshold.   
     
     
         13 . The vehicle of  claim 1 , wherein the stack node and the first access node are integrated in a first integrated circuit. 
     
     
         14 . The vehicle of  claim 1 , wherein the first access node does not implement the communication stack, and wherein the second access node does not implement the communication stack. 
     
     
         15 . The vehicle of  claim 1 , wherein the plurality of access nodes are deployed around the vehicle. 
     
     
         16 . The vehicle of  claim 1 , wherein determining that the quality of the second wireless communication link is greater than the quality of the first wireless communication link comprises determining that a received signal strength indicator (RSSI) value of the second wireless communication link is greater than an RSSI value of the first wireless communication link. 
     
     
         17 . The vehicle of  claim 1 , wherein the quality of the first wireless communication link is based on a signal to Interference plus noise ratio (SINR) level associated with the first wireless communication link. 
     
     
         18 . The vehicle of  claim 1 , wherein the quality of the first wireless communication link is based on a value measured by the first access node. 
     
     
         19 . The vehicle of  claim 1 , wherein the quality of the first wireless communication link is based on a value measured by the stack node based on a signal provided by the first access node. 
     
     
         20 . The vehicle of  claim 1 , wherein the stack node controller is configured to search for an access node of the plurality of access nodes when the quality of the first wireless communication link drops below a threshold, and wherein the stack node controller is configured to determine that the quality of the second wireless communication link is greater than a quality of the first wireless communication link in response to the searching.