Processing preamble usage data to select a handover target in a wireless communication system
View Patent ↗A source eNodeB initiates a handover of a user equipment. The source eNodeB receives preamble usage data transferred by a set of neighboring eNodeBs. The source eNodeB processes the preamble usage data to select a target eNodeB from the set of neighboring eNodeBs. The source eNodeB sends a handover request for delivery to the target eNodeB.
1. A method of operating an Evolved Node B (eNodeB) to initiate a handover, the method comprising:
receiving, by the eNodeB, preamble usage data for a set of neighboring eNodeBs, the preamble usage data transferred by corresponding eNodeBs of the set of neighboring eNodeBs over a backhaul link;
selecting, by the eNodeB, a target eNodeB from the set of neighboring eNodeBs based on the preamble usage data;
sending, by the eNodeB, a handover request for delivery to the target eNodeB.
2. The method of claim 1 further comprising:
processing the preamble usage data to identify an eNodeB of the set of neighboring eNodeBs having a highest count of unallocated contention-free preambles, wherein the identified eNodeB is selected as the target eNodeB.
3. The method of claim 2 , further comprising:
receiving a measurement report from a user equipment engaged in a voice over Long Term Evolution (VOLTE) session.
4. The method of claim 2 , further comprising:
receiving a measurement report from a user equipment having an RRC connection.
5. The method of claim 1 further comprising:
receiving a measurement report from a user equipment engaged in a VOLTE session; and processing the preamble usage data to identify an eNodeB of the set of neighboring eNodeBs operating a longest time with at least one unallocated contention-free preamble, wherein the identified eNodeB is selected as the target eNodeB.
6. The method of claim 1 further comprising:
processing the preamble usage data to identify an eNodeB of the set of neighboring eNodeBs having a lowest count of detected random access preambles, wherein the identified eNodeB is selected as the target eNodeB.
7. The method of claim 1 further comprising:
processing the preamble usage data to identify an eNodeB of the set of neighboring eNodeBs having a lowest count of bit errors corrected by Hybrid automatic repeat request (HARQ) on the physical random access channel (PRACH), wherein the identified eNodeB is selected as the target eNodeB.
8. The method of claim 1 further comprising:
processing the preamble usage data to identify an eNodeB of the set of neighboring eNodeBs having a lowest count of HARQ nacks of PRACH, wherein the identified eNodeB is selected as the target eNodeB.
9. The method of claim 1 further comprising:
processing the preamble usage data to identify an eNodeB of the set of neighboring eNodeBs operating a longest time without detecting a random access preamble, wherein the identified eNodeB is selected as the target eNodeB.
10. The method of claim 1 further comprising:
processing the preamble usage data to identify an eNodeB of the set of neighboring eNodeBs having a highest count of PRACH opportunities without a detected preamble, wherein the identified eNodeB is selected as the target eNodeB.
11. An Evolved Node B (eNodeB) system comprising:
a backhaul interface including communication circuitry configured to communicate with neighboring eNodeBs over a backhaul link;
a processing system including processing circuitry communicatively coupled to the backhaul interface and configured to:
receive, via the backhaul interface, preamble usage data for a set of neighboring eNodeBs, the preamble usage data transferred by corresponding eNodeBs of the set of neighboring eNodeBs over the backhaul link;
process the preamble usage data to select a target eNodeB from the set of neighboring eNodeBs based on the preamble usage data, and
direct the backhaul interface to send a handover request for delivery to the target eNodeB.
12. The eNodeB system of claim 11 wherein to process the preamble usage data, the processing system is configured to: identify an eNodeB of the set of neighboring eNodeBs having a highest count of unallocated contention-free preambles.
13. The eNodeB system of claim 11 further comprising:
an OFDMA interface,
wherein the processing system is further configured to receive, from the OFDMA interface, a measurement report transferred by a user equipment engaged in a voice over Long Term Evolution (VOLTE) session, and
wherein to process the preamble usage data, the processing system is configured to identify an eNodeB of the set of neighboring eNodeBs having a highest count of unallocated contention-free preambles.
14. The eNodeB system of claim 11 further comprising:
an OFDMA interface,
wherein the processing system is further configured to receive, from the OFDMA interface, a measurement report transferred by a user equipment having an RRC connection, and
wherein to process the preamble usage data, the processing system is configured to identify an eNodeB of the set of neighboring eNodeBs having a highest count of unallocated contention-free preambles.
15. The eNodeB system of claim 11 further comprising:
an OFDMA interface,
wherein the processing system is further configured to receive, from the OFDMA interface, a measurement report transferred by a user equipment engaged in a VOLTE session, and
wherein to process the preamble usage data, the processing system is configured to identify an eNodeB of the set of neighboring eNodeBs operating a longest time with at least one unallocated contention-free preamble.
16. The eNodeB system of claim 11 wherein to process the preamble usage data, the processing system is configured to identify an eNodeB of the set of neighboring eNodeBs having a lowest count of detected random access preambles.
17. The eNodeB system of claim 11 wherein to process the preamble usage data, the processing system is configured to identify an eNodeB of the set of neighboring eNodeBs having a lowest count of bit errors corrected by Hybrid automatic repeat request (HARQ) on the physical random access channel (PRACH).
18. The eNodeB system of claim 11 wherein to process the preamble usage data, the processing system is configured to identify an eNodeB of the set of neighboring eNodeBs having a lowest count of HARQ nacks of PRACH.
19. The eNodeB system of claim 11 wherein to process the preamble usage data, the processing system is configured to identify an eNodeB of the set of neighboring eNodeBs operating a longest time without detecting a random access preamble.
20. The eNodeB system of claim 11 wherein to process the preamble usage data, the processing system is configured to identify an eNodeB of the set of neighboring eNodeBs having a highest count of PRACH opportunities without a detected preamble.