Controlling handover of a UE based on data buffering
Disclosed is a method and system to help manage handover of a UE based on data buffering. In accordance with the disclosure, when a base station receives data destined for a UE, the base station may record the received data into a data buffer for temporary storage and retrieve the data at some later time to transmit the data to the UE. The base station may then determine, based at least in part on an amount of elapsed time from recording the data to retrieving the data, whether to invoke handover of the UE from being served by the base station to being served by a different, neighboring base station.
1. A method of managing handover of a user equipment device (UE) from a source base station serving the UE to a target base station, the method comprising:
receiving data by the source base station, the data being destined to the UE;
recording the received data in a data buffer of the source base station;
retrieving the recorded data from the data buffer;
transmitting the retrieved data from the source base station to the UE;
measuring elapsed time from the recording to the retrieving; and
invoking handover of the UE from the source base station to the target base station based at least in part on the measured elapsed time.
2. The method of claim 1 , further comprising determining that the measured elapsed time from the recording to the retrieving is greater than a predefined threshold, wherein invoking handover of the UE is based at least in part on the determining that the measured elapsed time is greater than the predefined threshold.
3. The method of claim 2 , wherein the received data comprises a plurality of data packets, wherein measuring elapsed time from the recording to the retrieving comprises measuring elapsed time from recording to retrieving each data packet of the plurality of data packets, wherein determining that the measured elapsed time from the recording to the retrieving is greater than the predefined threshold comprises determining that, for at least a threshold quantity of the plurality of data packets, the measured elapsed time from the recording and the retrieving is greater than the predefined threshold, and wherein invoking handover of the UE is further based on the measured elapsed time being greater than the predefined threshold for at least the threshold quantity of the plurality of data packets.
4. The method of claim 1 , wherein the received data comprises a plurality of data packets, wherein measuring elapsed time from the recording to the retrieving comprises determining an average elapsed time from recording to retrieving each data packet of the plurality of data packets, and wherein handover of the UE is invoked based on the determined average elapsed time being greater than a predefined threshold.
5. The method of claim 1 , wherein the received data comprises a plurality of data packets, and wherein measuring elapsed time from the recording to the retrieving comprises, for each respective data packet of the plurality of data packets:
identifying a first time at which the respective data packet is recorded in the data buffer;
identifying a second time at which the respective data packet is retrieved from the data buffer; and
determining a time difference between the first and second times.
6. A base station comprising:
an antenna structure for engaging in communication with user equipment devices (UEs) via an air interface;
a backhaul communication interface for engaging in backhaul communication on a core access network; and
a controller configured to control a handover of a UE served by the base station, wherein the controller is configured to:
receive data via the backhaul communication interface, the data being destined to the UE,
record the received data in a data buffer of the base station,
retrieve the recorded data from the data buffer,
transmit the retrieved data to the UE via the antenna structure,
measure elapsed time from the recording to the retrieving, and
invoke handover of the UE from the base station to a target neighboring base station based at least in part on the measured elapsed time.
7. The base station of claim 6 , wherein the controller is further configured to determine that the measured elapsed time from the recording to the retrieving is greater than a predefined threshold, wherein the controller invokes handover of the UE based at least in part on the determining that the measured elapsed time is greater than the predefined threshold.
8. The base station of claim 7 , wherein the received data comprises a plurality of data packets, wherein measuring elapsed time from the recording to the retrieving comprises measuring elapsed time from recording to retrieving each data packet of the plurality of data packets, wherein determining that the measured elapsed time from the recording to the retrieving is greater than the predefined threshold comprises determining that, for at least a threshold quantity of the plurality of data packets, the measured elapsed time from the recording and the retrieving is greater than the predefined threshold, and wherein invoking handover of the UE is further based on the measured elapsed time being greater than the predefined threshold for at least the threshold quantity of the plurality of data packets.
9. The base station of claim 6 , wherein the received data comprises a plurality of data packets, wherein measuring elapsed time from the recording to the retrieving comprises determining an average elapsed time from recording to retrieving each data packet of the plurality of data packets, and wherein handover of the UE is invoked based on the determined average elapsed time being greater than a predefined threshold.
10. The base station of claim 6 , wherein the received data comprises a plurality of data packets, and wherein measuring elapsed time from the recording to the retrieving comprises, for each respective data packet of the plurality of data packets:
identifying a first time at which the respective data packet is recorded in the data buffer;
identifying a second time at which the respective data packet is retrieved from the data buffer; and
determining a time difference between the first and second times.
11. The base station of claim 6 , wherein the base station is a Long Term Evolution (LTE) eNodeB and the air interface is an LTE air interface.
12. A method of managing handover of a user equipment device (UE) from a source base station serving the UE to a target base station, the method comprising:
receiving, by the source base station, data destined to the UE, wherein the received data comprises first data and second data;
recording the first and second data in a data buffer of the source base station;
retrieving the first data from the data buffer;
transmitting the first data from the source base station to the UE;
discarding the second data from the data buffer; and
performing a quality control process comprising at least one of the following:
(i) measuring elapsed time from the recording to the retrieving, and invoking handover of the UE from the source base station to the target base station based at least in part on the measured elapsed time, or
(ii) measuring a quantity of the discarded second data, and invoking handover of the UE from the source base station to the target base station based at least in part on the measured quantity of the discarded second data.
13. The method of claim 12 , wherein invoking handover of the UE from the source base station to the target base station based at least in part on the measured elapsed time comprises:
determining that the measured elapsed time from the recording to the retrieving is greater than a predefined threshold; and
invoking handover of the UE from the source base station to the target base station based at least in part on the determining that the measured elapsed time from the recording to the retrieving is greater than the predefined threshold.
14. The method of claim 12 , wherein invoking handover of the UE from the source base station to the target base station based at least in part on the measured quantity of the discarded second data comprises:
determining that the measured quantity of the discarded second data is greater than a predefined threshold; and
invoking handover of the UE from the source base station to the target base station based at least in part on the determining that the measured quantity of the discarded second data is greater than the predefined threshold.
15. The method of claim 12 , wherein performing the quality control process comprises:
measuring the elapsed time from the recording to the retrieving;
measuring the quantity of the discarded second data; and
invoking handover of the UE from the source base station to the target base station based on both (i) the measured elapsed time being greater than a predefined threshold amount and (ii) the measured quantity of the discarded second data being greater than a predefined threshold quantity.
16. The method of claim 13 , wherein the first data comprises a plurality of data packets, wherein measuring elapsed time from the recording to the retrieving comprises measuring elapsed time from recording to retrieving each data packet of the plurality of data packets, wherein determining that the measured elapsed time from the recording to the retrieving is greater than the predefined threshold comprises determining that, for at least a threshold quantity of the plurality of data packets, the measured elapsed time from the recording and the retrieving is greater than the predefined threshold, and wherein invoking handover of the UE based at least in part on the measured elapsed time comprises invoking handover of the UE based at least in part on the measured elapsed time being greater than the predefined threshold for at least the threshold quantity of the plurality of data packets.
17. The method of claim 12 , wherein the first data comprises a plurality of data packets, wherein measuring elapsed time from the recording to the retrieving comprises determining an average elapsed time from recording to retrieving each data packet of the plurality of data packets, and wherein invoking handover of the UE based at least in part on the measured elapsed time comprises invoking handover of the UE based at least in part on the determined average elapsed time being greater than a predefined threshold.
18. The method of claim 12 , further comprising determining a fullness state of the data buffer, wherein the source base station discards the second data from the data buffer based on the determined fullness state of the data buffer being greater than a predefined fullness threshold.
19. The method of claim 12 , further comprising determining that the second data has been recorded in the data buffer for at least a predefined threshold duration, wherein the source base station discards the second data from the data buffer based on the determining that the second data has been recorded in the data buffer for at least the predefined threshold duration.
20. The method of claim 12 , wherein the received data comprises a plurality of data packets, and wherein measuring elapsed time from the recording to the retrieving comprises, for each respective data packet of the plurality of data packets:
identifying a first time at which the respective data packet is recorded in the data buffer;
identifying a second time at which the respective data packet is retrieved from the data buffer; and
determining a time difference between the first and second times.