Patent Description:
The wireless communication networks have wireless access nodes which exchange wireless signals with the wireless user devices over radio frequency bands. The wireless signals use wireless network protocols like Fifth Generation New Radio (5GNR), Long Term Evolution (LTE), Institute of Electrical and Electronic Engineers (IEEE) <NUM> (WIFI), and Low-Power Wide Area Network (LP-WAN). The wireless access nodes exchange network signaling and user data with network elements that are often clustered together into wireless network cores.

The wireless network elements comprise Access and Mobility Management Functions (AMFs), User Plane Functions (UPFs), and the like. Some of the network elements are grouped into wireless network slices to deliver data communication services that feature low-latency, high-bandwidth, or some other service quality. For example, a UPF in a wireless network slice may be optimized for the augmented-reality application in the wireless user device that is served by the wireless network slice.

To select a wireless access node, the wireless user device scans frequencies to detect wireless access nodes and determine their Received Signal Strength (RSS). The wireless user device selects the wireless access node with the best RSS for wireless attachment. The wireless user device subsequently detects and reports RSS for the wireless access nodes, and the serving wireless access node may select another wireless access node based on RSS report. The serving wireless access node may select a target wireless access node to handover a wireless user device. The serving wireless access node may select a secondary wireless access node to deliver a dual connectivity service.

Unfortunately, the serving wireless access nodes do not effectively select other wireless access nodes to optimize service for the wireless user devices. Moreover, the serving wireless access nodes do not efficiently move the wireless user devices to their optimal wireless access nodes. <CIT> relates to triggering wireless local area network (WLAN) discovery and handover procedures in coexisted LTE and WLAN networks. A method comprises receiving, from a first base station, information that has been exchanged between the first eNB and a second base station and that relates to at least one wireless local area network access point connected or co-located with the first base station or the second base station; and performing a wireless local area network discovery procedure with the at least one wireless local area network access point based upon the received information. <CIT> relates to using data provided by an access point of a WLAN to assist a mobile device in cell reselection. If a serving cell of a cellular communications network is unsuitable for providing cellular service, a candidate cell co-located with the serving cell can be selected as the serving cell based on quality of service metrics associated with the serving cell and the candidate cell. The mobile device can be proactively commanded to switch to the candidate cell for receiving cellular service.

A wireless communication network serves User Equipment (UE) based on co-location and Received Signal Strength (RSS). A serving wireless access node selects itself for an uplink and downlink when no candidate wireless access nodes are co-located with the serving node. The serving node selects a candidate node for the uplink and downlink when the candidate node is co-located with the serving node and has an RSS level that exceeds a first threshold. The serving node selects itself for the uplink and selects a candidate node for the downlink when the candidate node is co-located with the serving node and has an RSS between the first threshold and a second threshold. The UE may trigger slice-specific access node selection by entering idle mode. The serving access node may condition the selection of a candidate access node on whether the candidate node supports a wireless network slice for the UE.

<FIG> illustrates an exemplary wireless communication network <NUM> to serve User Equipment (UE) <NUM> based on co-location and Received Signal Strength (RSS). Wireless communication network <NUM> comprises UE <NUM> and wireless access nodes <NUM>-<NUM>. Wireless access nodes <NUM>-<NUM> are co-located with access node <NUM>. Co-location requires that access nodes <NUM>-<NUM> be physically located within <NUM> feet of one another - often mounted on the same tower or structure. Wireless access nodes <NUM>-<NUM> are not co-located with wireless access node <NUM> because they are not within <NUM> feet of wireless access node <NUM>. UE <NUM> comprises a computer, phone, vehicle, sensor, robot, or some other data appliance with data communication circuitry. Wireless communication network <NUM> delivers wireless data service to UE <NUM>, and exemplary wireless data services include machine-control, internet-access, media-streaming, social-networking, and/or some other networking product. Wireless communication network <NUM> is simplified for clarity and typically includes far more UEs and access nodes than shown.

Various examples of network operation and configuration are described herein. In some examples, UE <NUM> wirelessly attaches to wireless access node <NUM> which is referred to as the "serving" access node. Other wireless access nodes <NUM>-<NUM> are referred to as "candidate" access nodes. Serving access node <NUM> determines if any candidate access nodes <NUM>-<NUM> are co-located with serving access node <NUM>. Although candidate access nodes <NUM>-<NUM> are co-located with serving access node <NUM> in this example, serving access node <NUM> selects itself for the uplink and the downlink for UE <NUM> when no candidate access nodes are co-located with serving wireless access node <NUM>. In response to the self-selection, serving access node <NUM> wirelessly exchanges user data with UE <NUM> over the uplink and the downlink. When a candidate access node is co-located with serving access node <NUM> and has an RSS level that exceeds a first threshold, serving access node <NUM> selects the candidate access node for the uplink and the downlink for UE <NUM>. For example, candidate access node <NUM> is co-located with serving access node <NUM> and may have an RSS that exceeds the first threshold. When multiple candidate access nodes have RSS levels that exceed the first threshold, the candidate with the highest RSS is selected. When candidate access node <NUM> is co-located with serving access node <NUM> and has the highest RSS that exceeds the first threshold, candidate access node <NUM> wirelessly exchanges the user data with UE <NUM> over the uplink and the downlink. When candidate access nodes are co-located with serving access node <NUM> and have RSS levels that fall below the first threshold but exceed a second threshold, serving access node <NUM> selects itself for the uplink for UE <NUM> and selects one of these candidate access nodes for the downlink for UE <NUM>. For example, candidate access node <NUM> is co-located with serving access node <NUM> and may have an RSS that falls below the first threshold but exceeds the second threshold. When multiple candidate access nodes have RSS levels between the first and second thresholds, the candidate with the highest RSS is selected. When candidate access node <NUM> is selected due to its co-location with serving access node <NUM> and a highest RSS between the first and second thresholds, candidate access node <NUM> wirelessly transfers user data to UE <NUM> over downlink while serving access node <NUM> receives user data from UE <NUM> over the uplink.

In some examples, UE <NUM> enters idle mode, and serving access node <NUM> selects one of candidate wireless access nodes <NUM>-<NUM> to serve UE <NUM> in response to UE <NUM> entering idle mode. UE <NUM> may use a wireless network slice before entering idle mode and serving access node <NUM> selects a candidate access node that supports the wireless network slice in response to UE <NUM> entering idle mode. The wireless network slice might comprise Ultra Reliable Low Latency Communications (URLLC), enhanced Mobile Broadband (eMBB), massive Machine Type Communication (mMTC), or some other network service. UE <NUM> may use Carrier Aggregation (CA) before entering idle mode and serving access node <NUM> could select a candidate access node that supports CA in response to UE <NUM> entering idle mode. Wireless access nodes could maintain data structures that translate neighbor access node identifiers into slice and CA capability.

Advantageously, serving wireless access node <NUM> effectively selects candidate wireless access nodes <NUM>-<NUM> to optimize service delivery for UE <NUM> based on RSS, co-location, and possibly slice support. Moreover, serving wireless access node <NUM> efficiently moves UE <NUM> to the optimal wireless access node - possibly optimized the UE's recent wireless network slice.

UE <NUM> and wireless access nodes <NUM>-<NUM> communicate over wireless links that use wireless technologies like Fifth Generation New Radio (5GNR), Long Term Evolution (LTE), Millimeter Wave (mmW), Institute of Electrical and Electronic Engineers (IEEE) <NUM> (WIFI), Low-Power Wide Area Network (LP-WAN), Bluetooth, and/or some other wireless communication protocols. In some examples, serving access node <NUM> comprises an LTE access node and candidate access nodes <NUM>-<NUM> comprise 5GNR access nodes. In other examples, serving access node <NUM> comprises a 5GNR access node and candidate access nodes <NUM>-<NUM> comprise LTE, mmW, WIFI, LP-WAN, Bluetooth, and/or some other type of wireless access nodes - including combinations thereof.

Wireless access nodes <NUM>-<NUM> communicate with one another and a network core over network connections that comprise metallic wiring, glass fibers, radio channels, or some other communication media. The network connections use technologies like IEEE <NUM> (ETHERNET), Internet Protocol (IP), Time Division Multiplex (TDM), Data Over Cable System Interface Specification (DOCSIS), General Packet Radio Service Transfer Protocol (GTP), mmW, 5GNR, LTE, WIFI, LP-WAN, Bluetooth, virtual switching, inter-processor communication, bus interfaces, and/or some other data communication protocols. UE <NUM> and wireless access nodes <NUM>-<NUM> include radios. UE <NUM> and wireless access nodes <NUM>-<NUM> comprise microprocessors, software, memories, transceivers, bus circuitry, and the like. The microprocessors comprise Digital Signal Processors (DSP), Central Processing Units (CPU), Graphical Processing Units (GPU), Application-Specific Integrated Circuits (ASIC), and/or the like. The memories comprise Random Access Memory (RAM), flash circuitry, disk drives, and/or the like. The memories store software like operating systems, user applications, radio applications, and network functions. The microprocessors retrieve the software from the memories and execute the software to drive the operation of wireless communication network <NUM> as described herein.

<FIG> illustrates an exemplary operation of wireless communication network <NUM> to serve UE <NUM> based on co-location and RSS. The operation may differ in other examples. UE <NUM> detects and reports Received Signal Strength (RSS) for wireless access nodes <NUM>-<NUM> to serving access node <NUM> (<NUM>). Serving access node <NUM> determines if any candidate access nodes <NUM>-<NUM> are co-located with serving access node <NUM> (<NUM>). When no candidate access node is co-located with serving wireless access node <NUM> (<NUM>), serving access node <NUM> selects itself for the uplink and the downlink for UE <NUM> (<NUM>) and wirelessly exchanges user data with UE <NUM> over the uplink and the downlink (<NUM>). When candidate access nodes are co-located with serving access node <NUM> (<NUM>), serving access node <NUM> determines when these candidates have an RSS level that exceeds a first threshold (<NUM>). When one of these candidate access nodes has an RSS level that exceeds the first threshold (<NUM>), serving access node <NUM> selects the candidate access node for the uplink and the downlink for UE <NUM> (<NUM>), and the selected candidate access node wirelessly exchanges the user data with UE <NUM> over the uplink and the downlink (<NUM>). When candidate access nodes are co-located with serving access node <NUM> (<NUM>) but have RSS levels that falls below the first threshold (<NUM>), serving access node <NUM> determines if any of these candidate access nodes have RSS levels that exceed a second threshold (<NUM>). When candidate access nodes are co-located with serving access node <NUM> (<NUM>) and have RSS levels lower than the first threshold (<NUM>) and higher than the second threshold (<NUM>), serving access node <NUM> selects itself for the uplink for UE <NUM> and selects the candidate access node for the downlink for UE <NUM> (<NUM>). Serving access node <NUM> wirelessly receives user data from UE <NUM> over the uplink (<NUM>) and the selected candidate access node transfers user data to UE <NUM> over the downlink (<NUM>).

<FIG> illustrates an exemplary operation of wireless communication network <NUM> to serve UE <NUM> based on co-location and RSS. The operation may differ in other examples. UE <NUM> wirelessly receives a pilot signal from serving Access Node (AN) <NUM> and responsively attaches to serving AN <NUM>. UE <NUM> receives pilot signals from candidate access nodes <NUM>-<NUM> and reports RSS to serving AN <NUM>. Serving AN <NUM> determines if any candidate access nodes are co-located with serving access node <NUM>. For example, serving AN <NUM> may host a data structure that correlates neighbor access nodes like candidate nodes <NUM>-<NUM> with their co-location status. When no candidate access nodes <NUM>-<NUM> are co-located with serving wireless access node <NUM>, serving access node <NUM> selects itself for the uplink and the downlink for UE <NUM>. In this example, candidate access nodes <NUM>-<NUM> are co-located. When some candidate access nodes are co-located with serving access node <NUM>, serving access node <NUM> determines if any of these candidate access nodes have an RSS level that exceeds a first threshold and selects one of these candidate access nodes for the uplink and downlink for UE <NUM>. In this example, the RSS for co-located nodes <NUM>-<NUM> falls below the first threshold. When none of the candidate access nodes that are co-located also have an RSS level that exceeds the first threshold, serving access node <NUM> determines if any of the co-located candidate access nodes have RSS levels that exceed a second threshold. In this example, serving access node <NUM> selects candidate access node <NUM> because candidate access node <NUM> is co-located with serving access node <NUM> and has an RSS level between the first threshold and the second threshold. Serving access node <NUM> signals candidate access node <NUM> to serve UE <NUM> over the downlink. Serving access node <NUM> signals UE <NUM> to use candidate access node <NUM> for the downlink. UE <NUM> transfers user data to external systems over the uplink to serving AN <NUM>. UE <NUM> receives user data from the external systems over the downlink from candidate access node <NUM>.

<FIG> illustrates exemplary Fifth Generation (<NUM>) wireless communication network <NUM> to serve UE <NUM> based on co-location, RSS, and slice. <NUM> wireless communication network <NUM> comprises an example of wireless communication network <NUM>, although network <NUM> may differ. <NUM> wireless communication network <NUM> comprises: UE <NUM>, RUs <NUM>-<NUM>, DUs <NUM>-<NUM>, CU <NUM>, and core <NUM>. RUs <NUM>-<NUM> are co-located within <NUM> feet of one another and may be mounted on the same tower.

UE <NUM> attaches to CU <NUM> over LTE RU <NUM> and DU <NUM>. UE <NUM> interacts with core <NUM> over LTE RU <NUM>, DU <NUM>, and CU <NUM> to authorize UE <NUM> for a wireless network slice like URLLC, eMBB, or mMTC. UE <NUM> exchanges user data with the wireless network slice in core <NUM> over LTE RU <NUM>, DU <NUM>, and CU <NUM>. The wireless network slice in core <NUM> may exchange the user data with external systems.

UE <NUM> eventually goes into idle mode. In idle mode, UE <NUM> occasionally checks the network for incoming messages. UE <NUM> determines RSS for 5GNR RUs <NUM>-<NUM> and reports the RSS levels to CU <NUM>. In response to UE <NUM> entering idle mode, CU <NUM> determines if any candidate RUs for UE <NUM> are co-located with serving RU <NUM>. When no candidate RUs are co-located with serving RU <NUM>, CU <NUM> selects serving RU <NUM> for the uplink and the downlink for UE <NUM>. In response to the selection of RU <NUM>, UE <NUM> exchanges user data with the wireless network slice in core <NUM> over the uplink and the downlink that traverse LTE RU <NUM>, DU <NUM>, and CU <NUM>.

In this example, CU <NUM> determines that candidate 5GNR RUs <NUM>-<NUM> are co-located with serving LTE RU <NUM>. If one of these candidate RUs <NUM>-<NUM> supports the wireless network slice and has an RSS level that exceeds a first threshold, then CU <NUM> selects that candidate RU for the uplink and the downlink for UE <NUM>. When co-located 5GNR RU <NUM> supports the wireless network slice and has an RSS that exceeds the first threshold, UE <NUM> exchanges user data with the wireless network slice over the uplink and the downlink that traverse 5GNR RU <NUM>, DU <NUM>, and CU <NUM>.

In this example, candidate 5GNR RUs <NUM>-<NUM> are co-located with serving LTE RU <NUM>. If one of candidate RUs <NUM>-<NUM> supports the wireless network slice and has an RSS level between the first threshold and a second threshold, then CU <NUM> selects that candidate RU for the downlink for UE <NUM>. When co-located 5GNR RU <NUM> supports the wireless network slice and has an RSS between the first threshold and the second threshold, UE <NUM> exchanges user data with the wireless network slice over the uplink that traverses LTE RU <NUM>, DU <NUM>, and CU <NUM> and over the downlink that traverses 5GNR RU <NUM>, DU <NUM>, and CU <NUM>.

In some examples, UE <NUM> and serving access node <NUM> use Carrier Aggregation (CA) before UE <NUM> enters idle mode. In response to UE <NUM> entering idle mode, CU <NUM> selects a co-located access node for the uplink and downlink for UE <NUM> when the candidate supports CA and has an RSS level that exceeds the first threshold. CU <NUM> may also select a co-located access node for the downlink for UE <NUM> when that candidate supports CA and has an RSS level between the first threshold and the second threshold.

<FIG> illustrates exemplary UE <NUM> in <NUM> wireless communication network <NUM>. UE <NUM> comprises an example of UE <NUM>, although UE <NUM> may differ. UE <NUM> comprises LTE radio <NUM>, 5GNR radios <NUM>, user circuitry <NUM>, and user components <NUM>. User components <NUM> comprise sensors, controllers, displays, or some other user apparatus that generates slice data. Radios <NUM>-<NUM> comprise antennas, amplifiers, filters, modulation, analog-to-digital interfaces, DSP, memory, and transceivers that are coupled over bus circuitry. User circuitry <NUM> comprises memory, CPU, user interfaces and components, and transceivers that are coupled over bus circuitry. The memory in user circuitry <NUM> stores an operating system (OS), user applications (APP), and network applications for Physical Layers (PHY), Media Access Controls (MAC), Radio Link Controls (RLC), Packet Data Convergence Protocols (PDCP), and Radio Resource Control (RRC) <NUM>. The antennas in LTE radio <NUM> are wirelessly coupled to LTE RU <NUM> over an LTE link. The antennas in 5GNR radios <NUM> are wirelessly coupled to 5GNR RUs <NUM>-<NUM> over a 5GNR links. Transceivers (XCVRs) in radios <NUM>-<NUM> are coupled to transceivers in user circuitry <NUM>. Transceivers in user circuitry <NUM> are coupled to user components <NUM>. The CPU in user circuitry <NUM> executes the operating system, user applications, and network applications to exchange network signaling and user data RUs <NUM>-<NUM> over radios <NUM>-<NUM>.

<FIG> illustrates exemplary Radio Units (RUs) <NUM>-<NUM>, Distributed Unit (DU) <NUM>, and Centralized Unit (CU) <NUM> in <NUM> wireless communication network <NUM>. RUs <NUM>-<NUM>, DU <NUM>, and CU <NUM> comprise examples of wireless access nodes <NUM>-<NUM>, although nodes <NUM>-<NUM> may differ. RUs <NUM>-<NUM> comprise examples of RUs <NUM>-<NUM>, although RUs <NUM>-<NUM> may fifer. DU <NUM> comprises an example of DU <NUM>, although DU <NUM> may differ. RUs <NUM>-<NUM> comprise antennas, amplifiers, filters, modulation, analog-to-digital interfaces, DSP, memory, radio applications, and transceivers that are coupled over bus circuitry. DU <NUM> comprises memory, CPU, user interfaces and components, and transceivers that are coupled over bus circuitry. The memory in DU <NUM> stores operating systems and network applications for PHY, MAC, and RLC. CU <NUM> comprises memory, CPU, user interfaces and components, and transceivers that are coupled over bus circuitry. The memory in CU <NUM> stores operating systems and network applications for PDCP and RRC <NUM>. The antennas in LTE RU <NUM> are wirelessly coupled to UE <NUM> over an LTE link. The antennas in 5GNR RUs <NUM>-<NUM> are wirelessly coupled to UE <NUM> over 5GNR links. Transceivers in RUs <NUM>-<NUM> are coupled to transceivers in DU <NUM>. Transceivers in DU <NUM> are coupled to transceivers in CU <NUM>. Transceivers in CU <NUM> are coupled to core <NUM>. The DSP and CPU in RUs <NUM>-<NUM>, DU <NUM>, and CU <NUM> execute the operating systems, radio applications, and network applications to exchange network signaling and user data with UE <NUM> and network core <NUM>.

<FIG> illustrates exemplary wireless access nodes <NUM>-<NUM> in <NUM> wireless communication network <NUM>. LTE access node <NUM> comprises LTE RU <NUM>, a portion of DU <NUM> (PHY, MAC, RLC), and a portion of CU <NUM> (PDCP, RRC <NUM>). 5GNR access node <NUM> comprises 5GNR RU <NUM>, a portion of DU <NUM> (PHY, MAC, RLC), and a portion of CU <NUM> (PDCP). 5GNR access node <NUM> comprises 5GNR RU <NUM>, a portion of DU <NUM> (PHY, MAC, RLC), and a portion of CU <NUM> (PDCP). 5GNR access node <NUM> comprises 5GNR RU <NUM>, a portion of DU <NUM> (PHY, MAC, RLC), and a portion of CU <NUM> (PDCP). 5GNR access node <NUM> comprises 5GNR RU <NUM>, a portion of DU <NUM> (PHY, MAC, RLC), and a portion of CU <NUM> (PDCP). 5GNR access node <NUM> comprises 5GNR RU <NUM>, a portion of DU <NUM> (PHY, MAC, RLC), and a portion of CU <NUM> (PDCP). RUs <NUM>-<NUM> wirelessly exchange network signaling and user data with UE <NUM>. RRC <NUM> in CU <NUM> exchanges network signaling with network core <NUM>. The PDCPs in CU <NUM> exchange user data with UE <NUM> and with the wireless network slice in network core <NUM>. When UE is attaches to LTE access node <NUM>, RRC <NUM> selects candidate 5GNR access nodes <NUM>-<NUM> to serve UE <NUM> based on RSS, co-location, slice, and CA as described herein.

<FIG> illustrates an exemplary operation of <NUM> wireless communication network <NUM> to serve UE <NUM> based on co-location, RSS, and slice. The operation may differ in other examples. LTE RU <NUM> transfers a pilot signal for LTE AN <NUM>. UE <NUM> receives the pilot signal from RU <NUM>. RRC <NUM> in UE <NUM> attaches to RRC <NUM> of LTE AN <NUM> in CU <NUM> over RU <NUM> and DU <NUM>. RRC <NUM> in UE <NUM> interacts with RRC <NUM> in CU <NUM> over RU <NUM> and DU <NUM> to authorize UE <NUM> for the wireless network slice. UE <NUM> exchanges user data with the wireless network slice in core <NUM> over LTE RU <NUM> and the LTE AN <NUM> portions of DU <NUM> and CU <NUM>.

UE <NUM> goes into idle mode, and in response, RRC <NUM> in UE <NUM> determines RSS for 5GNR RUs <NUM>-<NUM> based on their pilot signals. RRC <NUM> in UE <NUM> reports the RSS levels to RRC <NUM> in CU <NUM> over RU <NUM> and DU <NUM>. In response to UE <NUM> entering idle mode, RRC <NUM> for LTE AN <NUM> in CU <NUM> determines if any candidate 5GNR ANs <NUM>-<NUM> are co-located with serving LTE AN <NUM>. When no candidate ANs are co-located with serving LTE AN <NUM>, RRC <NUM> in CU <NUM> selects itself (LTE AN <NUM>) for the uplink and the downlink for UE <NUM> when it leaves idle mode. As shown in dotted lines if LTE AN <NUM> were selected (it is not in this example), UE <NUM> would exchange user data with the wireless network slice in core <NUM> over LTE RU <NUM> and the LTE AN <NUM> portions of DU <NUM> and CU <NUM>.

In this example, RRC <NUM> for LTE AN <NUM> in CU <NUM> determines that candidate ANs <NUM>-<NUM> are co-located with serving AN <NUM>. If one of these candidate ANs <NUM>-<NUM> supports the wireless network slice and has an RSS level that exceeds the first threshold, then RRC <NUM> for LTE AN <NUM> in CU <NUM> selects this candidate AN for the uplink and the downlink for UE <NUM> - otherwise AN <NUM> is still used. When candidate 5GNR AN <NUM> is selected for the uplink and the downlink for UE <NUM>, RRC <NUM> in CU <NUM> signals the RRC for AN <NUM> in CU <NUM> to serve UE <NUM> over the uplink and downlink to the wireless network slice. The RRC for AN <NUM> in CU <NUM> signals the RLC for AN <NUM> in DU <NUM> to serve UE <NUM> over the uplink and downlink to the wireless network slice. RRC <NUM> for AN <NUM> in CU <NUM> signals RRC <NUM> in UE <NUM> to use LTE AN <NUM> for the uplink and downlink to the wireless network slice. UE <NUM> attaches to the RLC of LTE AN <NUM> in DU <NUM> over RU <NUM>. As shown by dotted lines if 5GNR AN <NUM> were selected for the uplink and downlink (it is not in this example), UE <NUM> would exchange user data with the wireless network slice in core <NUM> over the uplink and the downlink that traverse 5GNR RU <NUM> and the 5GNR AN <NUM> portions of DU <NUM> and CU <NUM>. The operation proceeds to <FIG>.

<FIG> illustrates an exemplary operation of <NUM> wireless communication network <NUM> to serve UE <NUM> based on co-location, RSS, and slice. The operation may differ in other examples. The operation continues from the discussion of <FIG> above. If one of co-located and candidate ANs <NUM>-<NUM> supports the wireless network slice and has an RSS level between the first threshold and the second threshold (and no candidate ANs are above the first threshold), then RRC <NUM> for AN <NUM> in CU <NUM> selects this candidate AN for the downlink for UE <NUM> - otherwise AN <NUM> is still used. When candidate AN <NUM> is selected for the downlink for UE <NUM>, RRC <NUM> for AN <NUM> in CU <NUM> signals the RRC for AN <NUM> in CU <NUM> to serve UE <NUM> over the downlink for the wireless network slice. The RRC for AN <NUM> in CU <NUM> signals the RLC for AN <NUM> in DU <NUM> to serve UE <NUM> over the downlink for the wireless network slice. RRC <NUM> for AN <NUM> in CU <NUM> signals RRC <NUM> in UE <NUM> to use 5GNR AN <NUM> for the downlink from the wireless network slice. RRC <NUM> in UE <NUM> attaches to the RLC of LTE AN <NUM> in DU <NUM> over RU <NUM>. UE <NUM> transfers user data to the wireless network slice in core <NUM> over the uplink that traverses LTE RU <NUM> and the LTE AN <NUM> portions of DU <NUM> and CU <NUM>. UE <NUM> receives user data from the wireless network slice in core <NUM> over the downlink that traverses 5GNR RU <NUM> and the 5GNR AN <NUM> portions of DU <NUM> and CU <NUM>.

The wireless data network circuitry described above comprises computer hardware and software that form special-purpose networking circuitry to serve UEs based on co-location, RSS, and slice. The computer hardware comprises processing circuitry like CPUs, DSPs, GPUs, transceivers, bus circuitry, and memory. To form these computer hardware structures, semiconductors like silicon or germanium are positively and negatively doped to form transistors. The doping comprises ions like boron or phosphorus that are embedded within the semiconductor material. The transistors and other electronic structures like capacitors and resistors are arranged and metallically connected within the semiconductor to form devices like logic circuitry and storage registers. The logic circuitry and storage registers are arranged to form larger structures like control units, logic units, and Random-Access Memory (RAM). In turn, the control units, logic units, and RAM are metallically connected to form CPUs, DSPs, GPUs, transceivers, bus circuitry, and memory.

In the computer hardware, the control units drive data between the RAM and the logic units, and the logic units operate on the data. The control units also drive interactions with external memory like flash drives, disk drives, and the like. The computer hardware executes machine-level software to control and move data by driving machine-level inputs like voltages and currents to the control units, logic units, and RAM. The machine-level software is typically compiled from higher-level software programs. The higher-level software programs comprise operating systems, utilities, user applications, and the like. Both the higher-level software programs and their compiled machine-level software are stored in memory and retrieved for compilation and execution. On power-up, the computer hardware automatically executes physically-embedded machine-level software that drives the compilation and execution of the other computer software components which then assert control. Due to this automated execution, the presence of the higher-level software in memory physically changes the structure of the computer hardware machines into special-purpose networking circuitry to serve UEs based on co-location, RSS, and slice.

Claim 1:
A method of operating a wireless communication network to serve a User Equipment, UE, based on co-location and Received Signal Strength, RSS, levels, the method comprising:
a serving wireless access node selecting (<NUM>) the serving wireless access node for an uplink and a downlink for the UE when candidate wireless access nodes are not co-located with the serving wireless access node, and in response, wirelessly exchanging (<NUM>) user data with the UE over the uplink and the downlink;
the serving wireless access node selecting (<NUM>) one of the candidate wireless access nodes for the uplink and the downlink for the UE when the one of the candidate wireless access nodes is co-located with the serving wireless access node and has a highest one of the RSS levels that exceeds a first threshold;
the one of the candidate wireless access nodes wirelessly exchanging (<NUM>) the user data with the UE over the uplink and the downlink when the one of the candidate wireless access nodes is co-located with the serving wireless access node and has the highest one of the RSS levels that exceeds the first threshold;
the serving wireless access node selecting the serving wireless access node for the uplink for the UE and selecting (<NUM>) another one of the candidate wireless access nodes for the downlink for the UE when the other one of the candidate wireless access nodes has the highest one of the RSS levels that falls below the first threshold and that exceeds a second threshold, and wirelessly receiving (<NUM>) an uplink portion of the user data from the UE over the uplink; and
the other one of the candidate wireless access nodes wirelessly transferring (<NUM>) a downlink portion of the user data to the UE over the downlink when the other one of the candidate wireless access nodes is co-located with the serving wireless access node and has the highest one of the RSS levels that falls below the first threshold and exceeds the second threshold.