Systems and methods for determining access node candidates for handover of wireless devices

Patent metadata

Field	Value
Publication number	US-9794840-B1
Application number	US-201414287891-A
Country	US
Kind code	B1
Filing date	May 27, 2014
Priority date	May 27, 2014
Publication date	Oct 17, 2017
Grant date	Oct 17, 2017

Abstract

Systems and methods are described for determining candidates for handover of wireless devices in a wireless network. A first access node in communication with one or more wireless devices may receive signal information for second access nodes from the wireless devices. A communication link between the first access node and each second access node may be used to transmit second access node network characteristics to the first access node. The first access node may store information about second access nodes in a neighbor relation table. If a removal condition is satisfied, one or more second access nodes may be removed from the first access node neighbor relation table and may be blacklisted. Blacklisted second access nodes may be monitored for improvements in signal information or network characteristics. Improved second access nodes may be removed from the blacklist based on a comparison with threshold values for signal information and network characteristics.

First claim

What is claimed is:

1. A method for determining access node candidates for handover of one or more wireless devices in communication with a first access node in a wireless network, the method comprising:
upon removing one or more second access nodes from a first access node neighbor relation table (NRT) based on an NRT removal condition, adding one or more of the removed second access nodes to a blacklist stored by the first access node or by a controller node in communication with the first access node, wherein blacklisted second access nodes are restricted from addition to the first access node NRT by an automatic neighbor relation (ANR) protocol;
upon detection of a reference signal from the one or more of the removed second access nodes meeting a threshold, comparing current and historical values for a signal information and network characteristics with threshold values for each of the blacklisted second access nodes, the signal information comprising a signal level or interference of each of the blacklisted second access nodes;
identifying a specific combination of network characteristics of a blacklisted second access node for removal from the blacklist, wherein the specific combination of network characteristics comprises: a utilization indicator of the blacklisted second access node being higher than a utilization threshold, a number of active radio resource connections (RRC) of the blacklisted second access node being lower than a connectivity threshold, and an average data volume per RRC connection of the blacklisted second access node being below a capacity threshold; and
removing the blacklisted second access node from the blacklist.

2. The method of claim 1 , further comprising calculating the NRT removal condition based on an amount of time elapsed since the first access node has received the signal information for each of the blacklisted second access nodes.

3. The method of claim 1 , wherein the second access node network characteristics further comprise a handover failure rate, for each of the blacklisted second access nodes.

4. The method of claim 1 , wherein the signal information for the one or more second access nodes is received from one or more of a plurality of wireless devices in wireless communication with the first access node.

5. The method of claim 1 , wherein the network characteristics for each of the one or more second access nodes are received over a communication link between the first access node and each of the second access nodes.

6. The method of claim 1 , wherein the utilization indicator comprises a physical resource block (PRB) usage.

7. The method of claim 3 , further comprising removing one or more blacklisted second access nodes from the first access node blacklist when the received handover failure rate for each of the one or more blacklisted second access nodes decreases below a threshold handover failure rate.

8. A system for determining access node candidates for handover of wireless devices in a wireless network, the system comprising a controller node:
a first access node coupled to the controller node, configured to:
remove from a first access node neighbor relation table (NRT) one or more second access nodes for which an NRT removal condition is satisfied;
add one or more of the removed second access nodes to a blacklist stored by the first access node or by the controller node in communication with the first access node, wherein blacklisted second access nodes are restricted from addition to the first access node NRT by an automatic neighbor relation (ANR) protocol;
upon detection of a reference signal from the one or more of the removed second access nodes meeting a threshold, compare current and historical values for a signal information and network characteristics with threshold values for each of the blacklisted second access nodes, the signal information comprising a signal level or interference of each of the blacklisted second access nodes;
identify a specific combination of network characteristics of a blacklisted second access node for removal from the blacklist, wherein the specific combination of network characteristics comprises: a utilization indicator of the blacklisted second access node being higher than a utilization threshold, a number of active radio resource connections (RRC) of the blacklisted second access node being lower than a connectivity threshold, and an average data volume per RRC connection of the blacklisted second access node being below a capacity threshold; and
remove the blacklisted second access node from the blacklist.

9. The system of claim 8 , wherein the first access node is further configured to calculate the NRT removal condition based on an amount of time elapsed since the first access node has received signal information for each of the second access nodes.

10. The system of claim 8 , wherein the second access node network characteristics further comprise a handover failure rate, for each of the blacklisted second access nodes.

11. The system of claim 8 , wherein the first access node is further configured to receive the signal information for the one or more second access nodes from one or more of a plurality of wireless devices in wireless communication with the first access node.

12. The system of claim 8 , wherein the first access node is further configured to receive the network characteristics for each of the one or more second access nodes over a communication link between the first access node and each of the second access nodes.

13. The system of claim 8 , wherein the utilization indicator comprises a physical resource block (PRB) usage.

14. The system of claim 10 , wherein the first access node is further configured to remove one or more blacklisted second access nodes from the first access node blacklist when the received handover failure rate for each of the one or more blacklisted second access nodes decreases below a threshold handover failure rate.

Assignees

• Sprint Spectrum Lp
• Sprint Sprectrum LP

Inventors

• Tailor Pinalkumari
• Kim Yun-Sung
• Kaur Manmeet

Classifications

• H04W36/0083 Primary

  Determination of parameters used for hand-off, e.g. generation or modification of neighbour cell lists · CPC title

• H04W36/00837

  Determination of triggering parameters for hand-off · CPC title

• H04W36/00835 Primary

  Determination of neighbour cell lists · CPC title