Suppression of carrier-aggregation service by first access node in response to backhaul contstraint of second access node
A method and system to control carrier aggregation in a wireless communication system including a first access node and a second access node, where the first access node has a first respective backhaul connection, where the second access node has a second respective backhaul connection, where the first access node supports serving user equipment devices (UEs) with standalone connectivity, and where the first and second access nodes cooperatively support serving UEs with dual connectivity. A method includes detecting that the second respective backhaul connection of the second access node is threshold heavily loaded. And the method includes, based at least in part on the detecting that the second respective backhaul connection of the second access node is threshold heavily loaded, causing the first access node to suppress an extent of carrier-aggregation service that the first access node will provide to any standalone-connected UEs, to help free up capacity for dual-connectivity service.
1 . A method for controlling carrier aggregation, the method being operable in a wireless communication system in which a first access node has a first respective backhaul connection and a second access node has a second respective backhaul connection that is separate from the first respective backhaul connection, the method comprising:
determining that a first set of user equipment devices (UEs) have standalone connectivity and are connected to the first access node and that a second set of UEs have dual connectivity and are connected to both the first access node and the second access node;
detecting that the second respective backhaul connection of the second access node is threshold heavily loaded; and
based at least on the detecting, causing the first access node to suppress an extent of carrier-aggregation service that the first access node provides to the first set of UEs that have the standalone connectivity.
2 . The method of claim 1 , wherein the first access node and the second access node are disposed at a cell site, the cell site including a cell site router (CSR) that provides connectivity between the first access node and the second access node and a core network, wherein the first respective backhaul connection extends between the first access node and the CSR, and wherein the second respective backhaul connection extends between the second access node and the CSR.
3 . The method of claim 2 , wherein detecting that the second respective backhaul connection of the second access node is threshold heavily loaded comprises detecting that a rate of data flow between the second access node and the CSR is threshold high.
4 . The method of claim 2 , wherein detecting that the second respective backhaul connection of the second access node is threshold heavily loaded comprises detecting that a rate of packet loss for communication between the second access node and the CSR is threshold high.
5 . The method of claim 2 , wherein detecting that the second respective backhaul connection of the second access node is threshold heavily loaded comprises detecting that a quantity of data buffered for transmission over the second respective backhaul connection is threshold high.
6 . The method of claim 1 , wherein the detecting is carried out by the second access node, the method further comprising the second access node notifying the first access node of the detecting, and wherein the causing is carried out by the first access node responsive to the notifying.
7 . The method of claim 1 , wherein suppressing the extent of carrier-aggregation service that the first access node provides comprises blocking setup of carrier aggregation for one or more UEs of the first set of UEs.
8 . The method of claim 1 , wherein suppressing the extent of carrier-aggregation service that the first access node provides comprises transitioning to impose a maximum limitation on quantity of carriers in a connection respectively of each of the first set of UEs having connectivity with the first access node.
9 . The method of claim 1 , wherein suppressing the extent of carrier-aggregation service that the first access node provides comprises transitioning to impose a maximum limitation on quantity of UEs that the first access node would serve concurrently with carrier aggregation.
10 . The method of claim 1 , wherein the first access node provides first service according to a first radio access technology (RAT), and wherein the second access node provides second service according to a second RAT.
11 . A wireless communication system configured to control carrier aggregation, the wireless communication system comprising:
a first access node disposed at a cell site and configured to provide first coverage in which to serve first user equipment devices (UEs) with standalone connectivity with respect to the first access node, wherein the first access node has a first respective backhaul connection; and
a second access node disposed at the cell site and configured to provide second coverage in which to serve second UEs with dual connectivity with respect to the first access node and the second access node, wherein the second access node has a second respective backhaul connection,
wherein the first access node is configured to respond to at least detected threshold high backhaul load on the second respective backhaul connection of the second access node by suppressing an extent of carrier aggregation that the first access node provides to the first UEs having connectivity with the first access node.
12 . The wireless communication system of claim 11 , wherein the cell site includes a cell site router (CSR) that provides connectivity between the first access node and the second access node and a core network, wherein the first respective backhaul connection extends between the first access node and the CSR, and wherein the second respective backhaul connection extends between the second access node and the CSR.
13 . The wireless communication system of claim 12 , wherein the detected threshold high backhaul load on the second respective backhaul connection of the second access node is based on a rate of data flow between the second access node and the CSR.
14 . The wireless communication system of claim 12 , wherein the detected threshold high backhaul load on the second respective backhaul connection of the second access node is based on a rate of packet loss for communication between the second access node and the CSR.
15 . The wireless communications system of claim 12 , wherein the detected threshold high backhaul load on the second respective backhaul connection of the second access node is based on a quantity of data buffered for transmission over the second respective backhaul connection.
16 . The wireless communication system of claim 11 , wherein the first access node is configured to learn of the detected threshold high backhaul load on the second respective backhaul connection of the second access node by receiving from the second access node a notification of the detected threshold high backhaul load.
17 . The wireless communication system of claim 11 , wherein suppressing the extent of carrier-aggregation service that the first access node provides comprises at least one of (i) blocking setup of carrier aggregation for one or more first UEs, (ii) transitioning to impose a maximum limitation on quantity of carriers in a connection respectively of each of one or more second UEs having connectivity with the first access node, or (iii) transitioning to impose a maximum limitation on quantity of UEs that the first access node would serve concurrently with the carrier aggregation.
18 . The wireless communication system of claim 11 , wherein the first access node provides first service according to a first radio access technology (RAT), and wherein the second access node provides second service according to a second RAT.
19 . A first access node operable in a wireless communication system, the wireless communication system further including a second access node, the first access node being configured to provide first coverage and having a first respective backhaul connection, and the second access node being configured to provide second coverage and having a second respective backhaul connection, the first access node comprising:
a wireless communication interface;
a network communication interface;
at least one processor;
non-transitory data storage; and
program instructions stored in the non-transitory data storage and executable by the at least one processor to carry out operations for controlling carrier-aggregation, the operations comprising:
determining that a first set of user equipment devices (UEs) have standalone connectivity and are connected to the first access node and that a second set of UEs have dual connectivity and are connected to both the first access node and the second access node,
detecting that the second respective backhaul connection of the second access node is threshold heavily loaded, and
based at least on the detecting, causing the first access node to suppress an extent of carrier-aggregation service that the first access node provides to the first set of UEs that have the standalone connectivity.
20 . The first access node of claim 19 , wherein the first access node and the second access node are disposed at a cell site, the cell site including a cell site router (CSR) that provides connectivity between the first access node and the second access node and a core network, wherein the first respective backhaul connection extends between the first access node and the CSR, and wherein the second respective backhaul connection extends between the second access node and the CSR.