WO2018037333A1

WO2018037333A1 - Measurement coordination between two radio access technologies

Info

Publication number: WO2018037333A1
Application number: PCT/IB2017/055045
Authority: WO
Inventors: Tero H. M. HENTTONEN; Benoist P. Sebire; Amaanat ALI
Original assignee: Nokia Technologies Oy; Nokia Usa Inc.
Priority date: 2016-08-22
Filing date: 2017-08-21
Publication date: 2018-03-01

Abstract

Coordination is performed by a first base station and with a second base station for a joint operation of communication between the first base station, the second base station, and a UE. The first base station uses a first RAT to communicate with the UE and the second base station uses a different, second RAT to communicate with the UE. The coordinating determines a measurement configuration to be used by the UE to measure one or more cells of the second base station. The first base station sends the measurement configuration to the UE. As part of the joint operation, communication is performed by the first base station (and the second base station) with the UE. Measurements are made by the UE and sent to one or both of the first and second base stations, in accordance with the measurement configuration.

Description

MEASUREMENT COORDINATION BETWEEN TWO RADIO ACCESS

TECHNOLOGIES

TECHNICAL FIELD

[0001] This invention relates generally to wireless networks and, more specifically, relates to coordination between multiple base stations for measurements in wireless networks.

BACKGROUND

[0002] This section is intended to provide a background or context to the invention disclosed below. The description herein may include concepts that could be pursued, but are not necessarily ones that have been previously conceived, implemented or described. Therefore, unless otherwise explicitly indicated herein, what is described in this section is not prior art to the description in this application and is not admitted to be prior art by inclusion in this section. Abbreviations that may be found in the specification and/or the drawing figures are defined below, after the main part of the detailed description section.

[0003] Because the number, usage, and data requirements of wireless devices keeps increasing, wireless cellular networks are transitioning to new radios supporting new radio access technologies (RATs) to support these increases. The base stations (also called gNBs or NR eNBs) supporting the 5G RATs need to be able to communicate and coordinate with eNBs supporting LTE. This communication and coordination is commonly referred to as interworking, and the two base stations with two different RATs (or two different sets of RATs) need to interwork to be able to communicate with UEs using, e.g., dual connectivity and other techniques. To ensure the interworking is operating efficiently, information on UE radio conditions, e.g., based on UE measurements, can be beneficial to one or both of the base stations.

BRIEF SUMMARY

[0004] This section is intended to include examples and is not intended to be limiting.

[0005] In an exemplary embodiment, a method comprises coordinating, by a first base station and with a second base station, a joint operation of communication between the first base station, the second base station, and a user equipment, wherein the first base station uses a first radio access technology to communicate with the user equipment and the second base station uses a different, second radio access technology to communicate with the user equipment, and wherein the coordinating determines a measurement configuration to be used by the user equipment to measure one or more cells of the second base station. The method comprises sending by the first base station the measurement configuration to the user equipment. The method also comprises communicating, as part of the joint operation, by the first base station with the user equipment. [0006] An additional exemplary embodiment includes a computer program, comprising code for performing the method of the previous paragraph, when the computer program is run on a processor. The computer program according to this paragraph, wherein the computer program is a computer program product comprising a computer-readable medium bearing computer program code embodied therein for use with a computer.

[0007] An exemplary apparatus includes one or more processors and one or more memories including computer program code. The one or more memories and the computer program code are configured to, with the one or more processors, cause the apparatus to perform at least the following: coordinating, by a first base station and with a second base station, a joint operation of communication between the first base station, the second base station, and a user equipment, wherein the first base station uses a first radio access technology to communicate with the user equipment and the second base station uses a different, second radio access technology to communicate with the user equipment, and wherein the coordinating determines a measurement configuration to be used by the user equipment to measure one or more cells of the second base station; sending by the first base station the measurement configuration to the user equipment; and communicating, as part of the joint operation, by the first base station with the user equipment.

[0008] An exemplary computer program product includes a computer-readable storage medium bearing computer program code embodied therein for use with a computer. The computer program code includes: code for coordinating, by a first base station and with a second base station, a joint operation of communication between the first base station, the second base station, and a user equipment, wherein the first base station uses a first radio access technology to communicate with the user equipment and the second base station uses a different, second radio access technology to communicate with the user equipment, and wherein the coordinating determines a measurement configuration to be used by the user equipment to measure one or more cells of the second base station; code for sending by the first base station the measurement configuration to the user equipment; and code for communicating, as part of the joint operation, by the first base station with the user equipment.

[0009] In another exemplary embodiment, an apparatus comprises: means for coordinating, by a first base station and with a second base station, a joint operation of communication between the first base station, the second base station, and a user equipment, wherein the first base station uses a first radio access technology to communicate with the user equipment and the second base station uses a different, second radio access technology to communicate with the user equipment, and wherein the coordinating determines a measurement configuration to be used by the user equipment to measure one or more cells of the second base station; means for sending by the first base station the measurement configuration to the user equipment; and means for communicating, as part of the joint operation, by the first base station with the user equipment. [0010] In an additional exemplary embodiment, a method comprises participating in coordination, controlled by a first base station and participated in by a second base station, of a joint operation of communication between the first base station, the second base station, and a user equipment, wherein the first base station uses a first radio access technology to communicate with the user equipment and the second base station uses a different, second radio access technology to communicate with the user equipment, and wherein the coordination determines a measurement configuration to be used by the user equipment to measure one or more cells of the second base station. The method comprises communicating, as part of the joint operation, by the second base station with the user equipment.

[0011] An additional exemplary embodiment includes a computer program, comprising code for performing the method of the previous paragraph, when the computer program is run on a processor. The computer program according to this paragraph, wherein the computer program is a computer program product comprising a computer-readable medium bearing computer program code embodied therein for use with a computer.

[0012] An exemplary apparatus includes one or more processors and one or more memories including computer program code. The one or more memories and the computer program code are configured to, with the one or more processors, cause the apparatus to perform at least the following: participating in coordination, controlled by a first base station and participated in by a second base station, of a joint operation of communication between the first base station, the second base station, and a user equipment, wherein the first base station uses a first radio access technology to communicate with the user equipment and the second base station uses a different, second radio access technology to communicate with the user equipment, and wherein the coordination determines a measurement configuration to be used by the user equipment to measure one or more cells of the second base station; and communicating, as part of the joint operation, by the second base station with the user equipment.

[0013] An exemplary computer program product includes a computer-readable storage medium bearing computer program code embodied therein for use with a computer. The computer program code includes: code for participating in coordination, controlled by a first base station and participated in by a second base station, of a joint operation of communication between the first base station, the second base station, and a user equipment, wherein the first base station uses a first radio access technology to communicate with the user equipment and the second base station uses a different, second radio access technology to communicate with the user equipment, and wherein the coordination determines a measurement configuration to be used by the user equipment to measure one or more cells of the second base station; and code for communicating, as part of the joint operation, by the second base station with the user equipment.

[0014] In another exemplary embodiment, an apparatus comprises: means for participating in coordination, controlled by a first base station and participated in by a second base station, of a joint operation of communication between the first base station, the second base station, and a user equipment, wherein the first base station uses a first radio access technology to communicate with the user equipment and the second base station uses a different, second radio access technology to communicate with the user equipment, and wherein the coordination determines a measurement configuration to be used by the user equipment to measure one or more cells of the second base station; and means for communicating, as part of the joint operation, by the second base station with the user equipment.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In the attached Drawing Figures:

[0016] FIG. 1, split into FIGS. 1A and IB, is a block diagram of one possible and non-limiting exemplary system in which the exemplary embodiments may be practiced;

[0017] FIG. 2 is a flowchart and signaling diagram for LTE-NR initial measurement configuration in accordance with an exemplary embodiment;

[0018] FIG. 3 shows one example of information conveyed within the measurement configuration from an LTE eNB to the NR eNB, in an exemplary embodiment;

[0019] FIG. 4 shows one example of information conveyed within the measurement configuration of FIG. 3, as originally created by the LTE eNB;

[0020] FIG. 5 shows one example of information conveyed within the measurement configuration of FIG. 3, after modification by the NR eNB;

[0021] FIGS. 6 and 7 are logic flow diagrams for measurement coordination between two radio access technologies, and illustrate the operation of an exemplary method or methods, a result of execution of computer program instructions embodied on a computer readable memory, functions performed by logic implemented in hardware, and/or interconnected means for performing functions in accordance with exemplary embodiments. DETAILED DESCRIPTION OF THE DRAWINGS

[0022] The word "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. All of the embodiments described in this Detailed Description are exemplary embodiments provided to enable persons skilled in the art to make or use the invention and not to limit the scope of the invention which is defined by the claims.

[0023] The exemplary embodiments herein describe techniques for measurement coordination between two radio access technologies. Additional description of these techniques is presented after an exemplary system into which the exemplary embodiments may be used is described. [0024] Turning to FIG. 1, which is split into FIGS. 1A and IB, this figure shows a block diagram of one possible and non-limiting exemplary system in which the exemplary embodiments may be practiced. In FIG. 1, a user equipment (UE) 110 is in wireless communication with a wireless network 100. A UE is a wireless, typically mobile device that can access a wireless network. The UE 110 includes one or more processors 120, one or more memories 125, and one or more transceivers 130 interconnected through one or more buses 127. Each of the one or more transceivers 130 includes a receiver, Rx, 132 and a transmitter, Tx, 133. The one or more buses 127 may be address, data, or control buses, and may include any interconnection mechanism, such as a series of lines on a motherboard or integrated circuit, fiber optics or other optical communication equipment, and the like. The one or more transceivers 130 are connected to one or more antennas 128. The one or more memories 125 include computer program code 123. The UE 110 includes a measurement (Meas.) module 140, comprising one of or both parts 140-1 and/or 140-2, which may be implemented in a number of ways. The measurement module 140 may be implemented in hardware as measurement module 140-1, such as being implemented as part of the one or more processors 120. The measurement module 140-1 may be implemented also as an integrated circuit or through other hardware such as a programmable gate array. In another example, the measurement module 140 may be implemented as measurement module 140-2, which is implemented as computer program code 123 and is executed by the one or more processors 120. For instance, the one or more memories 125 and the computer program code 123 may be configured to, with the one or more processors 120, cause the user equipment 110 to perform one or more of the operations as described herein. The UE 110 communicates with two eNBs 170 via corresponding wireless links 111. That is, the UE 110 communicates with the MeNB via link 111-1 and communicates (e.g., possibly at the same time) with the SeNB 170-2 via link 111-2.

[0025] Each base station 170 is a base station that provides access by wireless devices such as the UE 110 to the wireless network 100. Each base station 170 (and the UE 110) supports dual connectivity. Concerning dual connectivity, see, e.g., the dual connectivity sections of 3GPP TS 36.300 V13.4.0 (2016-06). These sections include sections 4.9, 6.5, 7.6, and 10.1.2.8. The MeNB 170-1 is considered to be a "master" eNB, which uses a first RAT (or set of RATs, which may include multiple cells that may be on multiple bands) for LTE. It is noted that the

MeNB/SeNB may be in a HetNet scenario, e.g., with macro and small cells, or in a peer-to-peer relationship (e.g., macro cell to macro cell), or both; in fact, all possible scenarios are envisioned. Meanwhile, the SeNB 170-2 (also called an NR eNB or gNB) 170-2 is considered to be a "secondary" eNB, and this uses a second RAT (or set of RATs, which may include multiple cells that may be on multiple bands) for next generation (which may also be referred to as new radio) technologies. For instance, current LTE eNBs such as the LTE eNB 170-1 typically use "existing" (as of the time this is written) spectrum (and corresponding carriers) below 6 GHz. The new radio in the NR eNB 170-2 will use "new" (again, as of the time this is written) spectrum (and corresponding carriers), possibly including new spectrum below 6 GHz and new spectrum above 6 GHz, including millimeter wave spectrum. They may also use different air interfaces as part of the RATs. For instance, LTE eNBs 170-1 may use the Uu interface between the eNB 170-1 and the UE 110, while the NR eNB 170-2 may use a newly defined air interface between the NR eNB 170-2 and the UE 110. Other differences in RATs are also possible. It is noted that the gNB is a current acronym used for a new radio/new generation radio and corresponding network (e.g., access) node. The original acronym was next generation NB = ngNB, but that was abbreviated to have only three letters in RAN3, hence gNB. The name is not yet fixed, and may end up, e.g., as NR BS as well, but gNB is the current acronym.

[0026] The LTE eNB 170-1 is considered to be the master node for the embodiments herein, which means the LTE eNB 170-1 is primarily responsible for communication and coordination between the LTE eNB 170-1 and NR eNB 170-2. The role of the master eNB is explained in 3GPP TS 36.300. The communication and coordination between the eNBs 170-1 and 170-2 is commonly referred to as interworking. The NR eNB 170-2 in these examples is the secondary node for the embodiments herein. However, this relationship between master and secondary node can be reversed (e.g., the NR eNB 170-2 can be the master node and the LTE eNB 170-1 can be the secondary node).

[0027] The LTE eNB 170-1 includes one or more processors 152-1, one or more memories 155-1, one or more network interfaces (N/W I/F(s)) 161-1, and one or more transceivers 160- 1 interconnected through one or more buses 157- 1. Each of the one or more transceivers 160- 1 includes a receiver, Rx, 162-1 and a transmitter, Tx, 163-1. The one or more transceivers 160-1 are connected to one or more antennas 158-1. The one or more memories 155-1 include computer program code 153-1. The eNB 170-1 includes a measurement coordination (MC) module 150, comprising one of or both parts 150-1 and/or 150-2, which may be implemented in a number of ways. The measurement coordination module 150 may be implemented in hardware as measurement coordination module 150-1, such as being implemented as part of the one or more processors 152-1. The measurement coordination module 150-1 may be implemented also as an integrated circuit or through other hardware such as a programmable gate array. In another example, the measurement coordination module 150 may be implemented as measurement coordination module 150-2, which is implemented as computer program code 153-1 and is executed by the one or more processors 152-1. For instance, the one or more memories 155-1 and the computer program code 153-1 are configured to, with the one or more processors 152-1, cause the LTE eNB 170-1 to perform one or more of the operations as described herein. The one or more network interfaces 161-1 communicate over networks such as via the links 176 and 131. Two or more LTE or NR eNBs 170 communicate using, e.g., link 176. The link 176 may be wired or wireless or both and may implement, e.g., an Xn and/or X2 interface [0028] The one or more buses 157-1 may be address, data, or control buses, and may include any interconnection mechanism, such as a series of lines on a motherboard or integrated circuit, fiber optics or other optical communication equipment, wireless channels, and the like. For example, the one or more transceivers 160-1 may be implemented as a remote radio head (RRH) 195-1, with the other elements of the LTE eNB 170-1 being physically in a different location from the RRH, and the one or more buses 157-1 could be implemented in part as fiber optic cable to connect the other elements of the LTE eNB 170-1 to the RRH 195-1.

[0029] The NR eNB 170-2 includes one or more processors 152-2, one or more memories 155-2, one or more network interfaces (NAV I/F(s)) 161-2, and one or more transceivers 160-2 interconnected through one or more buses 157-2. Each of the one or more transceivers 160-2 includes a receiver, Rx, 162-2 and a transmitter, Tx, 163-2. The one or more transceivers 160-2 are connected to one or more antennas 158-2. The one or more memories 155-2 include computer program code 153-2. The NR eNB 170-2 includes a measurement coordination (MC) module 115, comprising one of or both parts 115-1 and/or 115-2, which may be implemented in a number of ways. The measurement coordination module 115 may be implemented in hardware as measurement coordination module 115-1, such as being implemented as part of the one or more processors 152-2. The measurement coordination module 115-1 may be implemented also as an integrated circuit or through other hardware such as a programmable gate array. In another example, the measurement coordination module 115 may be implemented as measurement coordination module 115-2, which is implemented as computer program code 153-2 and is executed by the one or more processors 152-2. For instance, the one or more memories 155-2 and the computer program code 153-2 are configured to, with the one or more processors 152-2, cause the NR eNB 170-2 to perform one or more of the operations as described herein. The one or more network interfaces 161-2 communicate over networks such as via the links 176 and 131.

[0030] The one or more buses 157-2 may be address, data, or control buses, and may include any interconnection mechanism, such as a series of lines on a motherboard or integrated circuit, fiber optics or other optical communication equipment, wireless channels, and the like. For example, the one or more transceivers 160-2 may be implemented as a remote radio head (RRH) 195-2 with the other elements of the NR eNB 170-2 being physically in a different location from the RRH, and the one or more buses 157-2 could be implemented in part as fiber optic cable to connect the other elements of the NR eNB 170-2 to the RRH 195-2.

[0031] It is noted that description herein may indicate that "cells" perform functions, but it should be clear that the base station that manages the cell will perform the functions. The cell makes up part of the base station. That is, there can be multiple cells per base station. For instance, there could be three cells for a single base station carrier frequency and associated bandwidth, each cell covering one-third of a 360 degree area so that the single base station's coverage area covers an approximate oval or circle. Furthermore, each cell can correspond to a single carrier and a base station may use multiple carriers. So if there are three 120 degree cells per carrier and two carriers, then the base station has a total of 6 cells.

[0032] The wireless network 100 may include a network control element (NCE) 190 that may include MME (Mobility Management Entity)/SGW (Serving Gateway) functionality, and which provides connectivity with a further network, such as a telephone network and/or a data communications network (e.g., the Internet). The base stations 170 are coupled via a link 131 to the NCE 190. The link 131 may be implemented as, e.g., an SI interface. The NCE 190 includes one or more processors 175, one or more memories 171, and one or more network interfaces (NAV I/F(s)) 180, interconnected through one or more buses 185. The one or more memories 171 include computer program code 173. The one or more memories 171 and the computer program code 173 are configured to, with the one or more processors 175, cause the NCE 190 to perform one or more operations.

[0033] The wireless network 100 may implement network virtualization, which is the process of combining hardware and software network resources and network functionality into a single, software -based administrative entity, a virtual network. Network virtualization involves platform virtualization, often combined with resource virtualization. Network virtualization is categorized as either external, combining many networks, or parts of networks, into a virtual unit, or internal, providing network-like functionality to software containers on a single system. Note that the virtualized entities that result from the network virtualization are still implemented, at some level, using hardware such as processors 152 or 175 and memories 155 and 171, and also such virtualized entities create technical effects.

[0034] The computer readable memories 125, 155-1 or -2, and 171 may be of any type suitable to the local technical environment and may be implemented using any suitable data storage technology, such as semiconductor based memory devices, flash memory, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory. The computer readable memories 125, 155-1 or -2 and 171 may be means for performing storage functions. The processors 120, 152-1 or -2, and 175 may be of any type suitable to the local technical environment, and may include one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on a multi-core processor architecture, as non-limiting examples. The processors 120, 152-1 or -2, and 175 may be means for performing functions, such as controlling the UE 110, LTE eNB 170-1 or NR eNB 170-2, and other functions as described herein.

[0035] Having thus introduced one suitable but non-limiting technical context for the practice of the exemplary embodiments of this invention, the exemplary embodiments and further information will now be described with greater specificity.

[0036] A study item on New Radio Access Technology (NR) (see NTT DOCOMO, "New SID Proposal: Study on New Radio Access Technology", 3GPP TSG RAN Meeting #71, Goteborg (or Gothenburg), Sweden, 7-10 March, 2016, RP-160671) and on Study on Architecture and Security for next Generation System (NG) (see SA WG3, "New Study on Architecture and Security for Next Generation System", 3GPP TSG SA Meeting #71, Gothenburg (or Goteborg), Sweden, 9-11 March 2016, SP-160227) have been agreed to in 3GPP. The LTE-NR tight interworking is an operation where LTE and NR radios are jointly operated to provide better data rates and improved reliability for UE data transmission.

[0037] To set up and maintain the LTE-NR for this joint operation (e.g., tight interworking), some UE measurements are required, which has been the subject of some discussion. For instance, in LTE DC, the RRM measurements are all decided purely by the master eNB 170-1 without any information from the secondary eNB 170-2. This is possible since both the MeNB and SeNB operate within the same LTE system, so the MeNB can utilize the criteria for SeNB mobility according to its own policies.

[0038] After examining these issues, the inventors have made the following assumptions, which are non-limiting examples of possible assumptions (depending on implementation).

[0039] Assumption 1: Use of joint operation may be decided by the master node (which may be assumed to be the LTE eNB 170-1 in many but not all situations). Note that while this may be a logical assumption, it could be possible to still obtain measurement configuration also from the NR entity. For example, evolved LTE (eLTE) is always connected to an NG core - so the measurement configuration for NR could be obtained via the NG core as well.

[0040] Assumption 2: The master node (=e.g., LTE) can configure measurements of secondary node access (=e.g., NR) radio quality. Together with assumption 1, this means that the master node is the one in an exemplary embodiment that would decide which measurements to configure and how to trigger joint operation, at least initially. As described below, communication between the master and second node may be performed to modify operation. In an exemplary embodiment, the master node decides on the measurements, but the SeNB can indicate modifications or other requests. The master node may or may not take the SeNB requests into account.

[0041] Assumption 3: The measurement configuration does not have to be changed depending on the joint operation state. For instance, the measurements configured initially (e.g., for determining whether the master node decides to request joint operation from the secondary node) are independent of the joint operation status and can be maintained (at the master node' s discretion).

[0042] Assumption 4: The secondary access (e.g., NR) measurements are configured within the master (=e.g., LTE) RRC measurement framework. For instance, this can mean that the measurements for the NR are defined within the LTE RRC measurement framework independent of the joint operation, and are just configured in the same way as any other measurements in the LTE RRC measurement framework. [0043] Assumption 5: The master node (e.g., LTE) configures the measurements but the secondary node (=e.g., NR) can request which measurement events to configure. The master node (=e.g., LTE) can decide which events to accept. It seems reasonable to assume that, like with DC, the UE would monitor whether the secondary (NR) link would be operational.

[0044] Assumption 6: The UE 110 monitors the secondary node (=NR) for radio link failure (which may be handled according to secondary radio link failure (S-RLF) monitoring according to LTE DC terminology as per 3GPP TS 36.300). Further, the UE could either stop the measurements at S-RLF or continue them. If the UE were to stop the measurements, the LTE eNB 170-1 should be notified, and the eNB/UE configuration could have a mismatch. Therefore, it is better to retain the configuration until told otherwise.

[0045] Assumption 7: The UE 110 retains at least the measurement configuration for secondary node after RLF of the secondary node. However, it seems reasonable to assume that the master (LTE) node could still release the configuration even after RLF on the secondary node.

[0046] Assumption 8: The master (= e.g., LTE) can always release the secondary (=e.g., NR) measurement configuration. This means that the master is able to release the configuration without consulting the secondary node, e.g., in case the secondary node fails and is not reachable anymore.

[0047] Based on these assumptions, we propose in an exemplary embodiment that the LTE-NR measurement configuration exchanged between LTE and NR eNBs can include exact configuration along with a "purpose" of each measurement. The purpose can then be used to determine (e.g., or align) how to configure the measurements (and in turn synchronize the measurement reporting from the UE).

[0048] In brief, the stages of doing so are explained as follows for an exemplary embodiment. Firstly, the LTE eNB 170-1 requests joint operation with the NR eNB 170-2, and the LTE eNB 170-1 will input its existing NR measurements along with a measurement "purpose" for each of the measurements. Secondly, the NR eNB 170-2 can then indicate/propose a similar container with potentially updated configuration including the "purpose" of the event(s) and/or exact parameter configuration for each event and (optionally) whether the NR eNB 170-2 wishes to receive the measurement reports directly from UE 110. The NR eNB 170-2 sends this proposed measurement configuration to LTE eNB 170-1. Thirdly, the LTE eNB 170-1 then decides which parts of the proposed configuration to accept, informs the NR eNB 170-2 of the final configuration. Lastly, the LTE eNB 170-1 sends the actual configuration of the measurement events to the UE 110.

[0049] Hence, the LTE eNB 170-1 (assuming the LTE eNB is the master) remains in full control of the measurements while still allowing the NR eNB 170-2 to assist in the details of the measurement events. [0050] When the NR eNB 170-2 signals to the LTE eNB to receive the measurement reports directly from the UE 110, the LTE eNB 170-1 is free to either configure the UE to send the measurement reports to both the NR eNB 170-2 and the LTE eNB 170-2, or to only one of the LTE eNB 170-1 or the NR eNB 170-2. In the latter case, the LTE eNB 170-1 may configure itself or the NR eNB 170-2 to forward such measurement reports.

[0051] As a consequence, upon receiving the configuration, the UE knows which measurements to perform and to which node to report them (LTE eNB, NR eNB or both).

[0052] The techniques can be characterized by, e.g., the following embodiments:

[0053] 1) A first node maintains a measurement configuration related to joint operation with a second node.

[0054] la) The configuration may comprise a plurality of measurement "items" that contain at least configuration and optionally also the "purpose" for which resource management purpose the item is intended.

[0055] lb) Such purpose may be, e.g., "change of cell", "release of cell", "release of joint operation", "add joint operation", "release joint operation", and the like.

[0056] 2) When requesting joint operation with a second node, the first node may provide the measurement configuration to the second node.

[0057] 2a) The second node determines whether it wishes to alter the received measurement configuration.

[0058] 2b) If the second node desires additional information to be measured or modifications to the configuration provided by the first node, the second node may provide information regarding modified configuration (e.g., additions or deletions of events, or parameter changes to some events) to the first node's configuration.

[0059] 2c) The second node may also indicate for each measurement event in the measurement configuration whether the second node desires to receive measurement reports either directly from the UE, from the first node, or from both.

[0060] 3) If the first node receives information regarding modified measurement configuration from the second node, the first node decides whether to act according to none, some or all parts of the information regarding modified measurement configuration, and the first node creates the final measurement configuration.

[0061] 3a) After creating the final measurement configuration, the first node indicates the final measurement configuration to the second node and to the UE. This causes the UE to start using the measurement configuration.

[0062] FIG. 2 is a flowchart and signaling diagram for LTE-NR initial measurement configuration in accordance with an exemplary embodiment, and indicates one example of the above operations. In FIG. 2, the UE and LTE eNB 170-1 communicate via a Uu interface 410 (e.g., over the link 111-1), and the LTE eNB 170-1 communicates with the NR eNB 170-2 via, e.g., an Xn interface 420, e.g., over the link 176.

[0063] In operation 1, the LTE eNB 170-1 configures the measurement configuration for joint operation for the UE 110, which configuration has been decided by LTE (e.g., the LTE eNB 170-1). This configuration is performed via a message in this example. In response, the UE 110 takes measurements for joint operation according to the NR measurement configuration 423. The measurements for joint operation may be from both LTE and NR eNBs - e.g., this could be an event that triggers when both LTE and NR measurements indicate good enough quality. See operation 425. In operation 2, the UE 110 responds via a message with a measurement report 428 for the joint operation according to the measurement configuration 423. In operation 3, the LTE eNB 170-1 makes a decision to request LTE-NR joint operation. Responsive to this, in operation 4, the LTE eNB 170-1 requests 429 via a message the LTE-NR joint operation (which includes the NR measurement configuration 300-1). In other words, this request 429 is to start actual DC operation for both the LTE and NR eNBs and the UE and both LTE/NR nodes and the UE are aware of this operation.

[0064] In operation 5, in response to receiving the request, the NR eNB 170-2 decides whether the measurement configuration is sufficient for the NR eNB 170-2. Possible operations for this include operation 5-1, in which in response to the measurement configuration not being sufficient, the NR eNB 170-2 makes modifications to the measurement configuration. Another possible operation includes operation 5-2, in which in response to the measurement configuration being sufficient, the NR eNB 170-2 does not make modifications to the measurement configuration. The modifications 430 may include one or more of the following modifications: adding additional events 430-1; deleting events 430-2; and/or performing parameter changes to one or more events 430-3.

[0065] In operation 6, the NR eNB 170-2 indicates the proposed NR measurement configuration 300-2 (with modifications, if any) via a message to the LTE eNB 170-1. In block 170-1, the LTE eNB 170-1 decides how to accomplish the measurement configuration. In operation 8, the LTE eNB 170-1 indicates, via a message, the final NR measurement configuration 300-3 to the NR eNB 170-2.

[0066] In operation 9, the LTE eNB 170-1 reconfigures, via signaling, the final measurement configuration 300-4 including the LTE-NR joint operation configuration (e.g., including measurement configuration for both LTE and NR) to the UE 110. The UE 110, LTE eNB 170-1 and NR eNB 170-2 then start (see operation 433) LTE-NR joint operation, e.g., to perform dual connectivity. In response to operation 9, the UE 110 in operation 435 takes measurements of the LTE eNB 170-1 and NR eNB 170-2, in accordance with the final joint operation configuration received in operation 9. That is, the UE will perform measurements (e.g., RSRP, RSRQ, or other UE radio conditions) of the LTE eNB 170-1 and NR eNB 170-2 according to the configuration and report (see operation 10) the results to the LTE eNB and/or NR eNB according to its configuration for measurement reporting. FIG. 2 only shows the UE reporting to the LTE eNB 170-1, but this is merely exemplary. Taking measurements is an end result of the changing configuration. The LTE eNB 170- 1 then uses that reported information to decide whether the LTE eNB can continue, revise, or stop the joint operation (see operation 450). Additionally, NR cells can be added and removed based on the reported measurement results. The LTE eNB 170-1 can filter the results in operation 440 and deliver filtered results to the NR eNB 170-2 in operation 11. Such results delivered to the NE eNB 170-2 may be some or all of the results reported by the UE 110 to the LTE eNB 170-1 in operation 10. See examples of filtering provided below.

[0067] One or more of the measurement configurations 300-1, 300-2, 300-3, and 300-4 may be the same. One or more of these may also be different. An example using different measurement configurations 300-1, 300-2 is provided below, but this is not limiting.

[0068] Furthermore, when a discrepancy exists between the configurations requested by the second node (e.g., the NR eNB 170-2 in FIG. 2) and the final configuration signaled to the UE by the first node (e.g., the LTE eNB 170-1 in FIG. 2), the node receiving the measurement reports may decide to filter them before forwarding them to the other node. This would be particularly useful for periodic measurements. Consider the following examples.

[0069] a) If the second node expects a periodicity of 500ms while the first node settles for a periodicity of 250ms, and the UE is configured to send the measurement reports to the first node with a 250ms periodicity, the first node then forwards only every second report to the second node.

[0070] b) If the second node expects a periodicity of 100ms while the first node settles for a periodicity of 300ms, and the UE is configured to send the measurement reports to the second node with a 100ms periodicity, the second node then forwards only every third report to the first node.

[0071] The table in FIG. 3 shows one example of the information conveyed within the measurement configuration 300 from LTE eNB to the NR eNB. The measurement configuration 300 in this examples comprises N measurement items #1 310-1, #2 310-2, through #N 310-N. Each measurement item 310 comprises a corresponding purpose 320, an event ID 330, one or more triggering parameters 340, and a "Report delivered to NR?" field 350. The purpose 320 may be, e.g., "change of cell", "release of cell", "release of joint operation", "add joint operation", "release joint operation", and the like. The event ID 330 is a listing of the event ID, which, e.g., allows for it to be determined if a measurement item 310 is missing or corrupted. The triggering parameters 340 are the parameters used to trigger the purpose 320. The "Report delivered to NR?" field 350 indicates whether the reports should be delivered to the NR eNB 170-2 or not (e.g., TRUE = deliver to NR; FALSE = do not deliver to NR). These entries in the measurement items 320 are merely exemplary and similar or different entries may be used, and there may be fewer or more entries. [0072] A specific example is now presented. As a concrete example, once the LTE eNB 170-1 decides (at operation 3 in FIG. 2) to request NR-LTE operation, the LTE eNB 170-1 then delivers its proposed measurement configuration to NR eNB at operation 4 of FIG. 2. The proposed measurement configuration for this example is illustrated by FIG. 4. In this example, there are two measurement items #1 310-1 and #2 310-2 shown. The measurement item #1 310-1 comprises the following: the purpose 320-1 of start joint operation (op.); the event ID 330-1 of 1 (one); the triggering parameters 340-1 of LTE-NR A3 (340-11), RSRP (340-12), threshold = -1 dB (340-13), and periodicity = event (340-14); and the "Report delivered to NR?" field 350-1 is FALSE.

[0073] The measurement item #2 310-2 comprises the following: the purpose 320-2 of release joint operation (op.); the event ID 330-1 of 2 (two); the triggering parameters 340-2 of NR measurement event A2 (340-21), RSRQ (340-22), threshold = -95 dB (340-23), and periodicity = event (340-24); and the "Report delivered to NR?" field 350-1 is FALSE. Basically, the measurement item #1 310-1 indicates the purpose is to start joint operation based on the LTE-NR measurement event A3 (i.e., NR neighbor becomes an offset better than LTE serving cell) having an RSRP measurement given a threshold of -1 dB with a periodicity of a single event. For this situation, the expectation is that if LTE quality is 1 dB < NR quality, then joint operation can start. The measurement item #2 310-2 indicates the purpose is to release joint operation based on the NR measurement event A2 (i.e., the serving cell becomes lower than a threshold) having an RSRQ measurement given a threshold of -95 dB with a periodicity of a single event.

[0074] Then NR eNB 170-2 then decides (in operation 5 of FIG. 2) to modify the measurement configuration as illustrated in FIG. 5. The reference number 510 indicates the configuration that was modified by the NR eNB 170-2. In this case, the triggering parameter 340-12 has been modified (510-1) from "threshold = -1 dB" to "threshold = 0 dB", and the "Report delivered to NR?" field 350-1 has been modified (510-2) from FALSE to TRUE. This modifies the threshold for RSRP to zero (0) dB and also sets the "Report delivered to NR?" field 350-1 to TRUE to that RSRP reports are delivered to the NR eNB 170-2.

[0075] Once receiving this in operation 6, the LTE eNB decides (in operation 7) whether to accept the proposed measurement configuration modifications or not and informs the NR eNB of the final measurement configuration (in operation 8) and configures the UE with the same final measurement configuration (in operation 9).

[0076] FIGS. 6 and 7 are logic flow diagrams for measurement coordination between two radio access technologies, and illustrate the operation of an exemplary method or methods, a result of execution of computer program instructions embodied on a computer readable memory, functions performed by logic implemented in hardware, and/or interconnected means for performing functions in accordance with exemplary embodiments. FIG. 6 is assumed to be from the perspective of a master node such as the MeNB 170-1, e.g., under control of the measurement control module 150-1. FIG. 7 is assumed to be from the perspective of a secondary node such as the SeNB 170-2.

[0077] Referring to FIG. 6, in block 610, MeNB 170-1 performs coordinating, by a first base station (the MeNB in an example) and with a second base station (the SeNB in this example, a joint operation of communication between the first base station, the second base station, and a user equipment, The first base station uses a first radio access technology to communicate with the user equipment and the second base station uses a different, second radio access technology to communicate with the user equipment. The coordinating determines a measurement configuration to be used by the user equipment to measure one or more cells of the second base station.

[0078] In block 620, the MeNB performs sending by the first base station the measurement configuration to the user equipment. The MeNB, in block 630, performs communicating, as part of the joint operation, by the first base station with the user equipment.

[0079] In the examples that follow, the method in FIG. 6 is called example 1.

[0080] Example 2. The method of example 1, further comprising the first base station receiving, based on the measurement configuration, measurement reports from the user equipment comprising one or more measurements of radio conditions at the user equipment based on one or more signals from the second base station, and the first base station reporting the one or more measurements to the second base station.

[0081] Example 3. The method of example 2, wherein:

[0082] the measurement reports further comprise one or more first measurements from the user equipment of radio conditions at the user equipment based on one or more signals from the first base station;

[0083] the one or more measurements of the radio conditions at the user equipment based on the one or more signals from the second base station are second measurements; and

[0084] the first base station filters out the one or more second measurements prior to forwarding the one or more second measurements to the second base station.

[0085] Example 4. The method of example 3, wherein:

[0086] the first base station receives the measurement reports at a periodicity;

[0087] the measurement configuration has a difference in periodicity between a first periodicity for the one or more first measurements and a second periodicity for the one or more second measurements; and

[0088] the forwarding the one or more second measurements to the second base station occurs based on the second periodicity for the one or more second measurements.

[0089] Example 5. The method of example 1, wherein the measurement configuration includes a configuration for the user equipment to send measurement reports only to the second base station, and wherein the method further comprises receiving by the first base station measurement reports from the second base station of one or more measurements of radio conditions at the user equipment based on one or more signals from the first base station.

[0090] Example 6. The method of example 1, further comprising the first base station receiving, based on the measurement configuration, measurement reports from the user equipment comprising one or more measurements of radio conditions at the user equipment based on one or more signals from the first base station.

[0091] Example 7. The method of any one of examples 1 to 6, wherein coordinating further comprises:

[0092] sending from the first base station to the second base station a request for joint operation, wherein the request comprises a proposed measurement configuration to be used by the user equipment to measure radio conditions at the user equipment for the second base station;

[0093] receiving at the first base station a response from the second base station comprising a second proposed measurement configuration, the second proposed measurement configuration comprising either the proposed measurement configuration or a modified measurement configuration ;

[0094] determining a final measurement configuration based on the second proposed measurement configuration; and

[0095] sending a message to the user equipment indicating the final measurement configuration.

[0096] Example 8. The method of example 7, wherein the second proposed measurement configuration comprises the modified measurement configuration, and modifications to the proposed measurement configuration comprise one or more of the following: one or more additional events have been added; one or more events have been deleted; and one or more parameter changes have been performed to one or more events.

[0097] Example 9. The method of one of examples 7 or 8, wherein the final measurement configuration further comprises indication of measurement configuration to be used by the user equipment to measure radio conditions at the user equipment for the first base station.

[0098] Example 10. The method of any one of examples 1 to 9, wherein coordinating comprises communicating one or more measurement items for the measurement configuration between the first and second base stations, and at least one of the measurement items comprises one or more of the following: a value indicating a purpose of a measurement configuration to be used by the user equipment; one or more triggering parameters indicating when the measurement should be performed; and an indication of whether a report for the measurement should be delivered to the second base station.

[0099] Example 11. The method of any one of examples 1 to 10, wherein one of the first radio access technology or the second radio access technology is a long term evolution technology and an other of the first radio access technology or second radio access technology is a new radio technology.

[00100] Referring to FIG. 7, this is assumed to be performed by the SeNB 170-2. In block 710, the SeNB performs participating in coordination, controlled by a first base station (the MeNB in an example) and participated in by a second base station (the SeNB in this example), of a joint operation of communication between the first base station, the second base station, and a user equipment. The first base station uses a first radio access technology to communicate with the user equipment and the second base station uses a different, second radio access technology to communicate with the user equipment. The coordination determines a measurement configuration to be used by the user equipment to measure one or more cells of the second base station. In block 720, the SeNB performs communicating, as part of the joint operation, by the second base station with the user equipment.

[00101] The method in FIG. 7 is referred to as example 12 below.

[00102] Example 13. The method of example 12, further comprising the second base station receiving, based on the measurement configuration, measurement reports from the user equipment comprising one or more measurements of radio conditions at the user equipment based on one or more signals from the first base station, and the second base station forwarding the one or more measurements to the first base station.

[00103] Example 14. The method of example 13, wherein:

[00104] the one or more measurements of the radio conditions at the user equipment based on the one or more signals from the first base station are first measurements;

[00105] the measurement reports further comprise one or more second measurements from the user equipment of radio conditions at the user equipment based on one or more signals from the second base station; and

[00106] the second base station filters out the one or more first measurements prior to forwarding the one or more first measurements to the first base station.

[00107] Example 15. The method of example 14, wherein:

[00108] the second base station receives the measurement reports at a periodicity;

[00109] the measurement configuration has a difference in periodicity between a first periodicity for the one or more first measurements and a second periodicity for the one or more second measurements; and

[00110] the forwarding the one or more first measurements to the first base station occurs based on the first periodicity for the one or more first measurements.

[00111] Example 16. The method of example 12, further comprising receiving, based on the measurement configuration, measurement reports from the first base station of one or more measurements of radio conditions at the user equipment based on one or more signals from the second base station. [00112] Example 17. The method of example 12, further comprising the second base station receiving, based on the measurement configuration, measurement reports from the user equipment comprising one or more measurements of radio conditions at the user equipment based on one or more signals from the second base station.

[00113] Example 18. The method of any one of examples 12 to 17, wherein participating in the coordination further comprises:

[00114] receiving, at the second base station and from the first base station, a request for joint operation, wherein the request comprises a proposed measurement configuration to be used by the user equipment to measure radio conditions at the user equipment for the second base station;

[00115] deciding by the second base station whether the proposed measurement configuration is sufficient, and in response to the proposed measurement configuration not being sufficient, modifying the proposed measurement configuration to create a modified measurement configuration;

[00116] sending, by the second base station and toward the first base station, a response comprising the second proposed measurement configuration, the second proposed measurement configuration comprising either the proposed measurement configuration or the modified measurement configuration; and

[00117] receiving, at the second base station and from the first base station, a final measurement configuration based on the second proposed measurement configuration, and preparing to receive measurement reports based on the final measurement configuration.

[00118] Example 19. The method of example 18, wherein the second proposed measurement configuration comprises the modified measurement configuration, and modifications to the proposed measurement configuration comprise one or more of the following: one or more additional events have been added; one or more events have been deleted; and one or more parameter changes have been performed to one or more events.

[00119] Example 20. The method of any one of examples 12 to 20, wherein the participating in the coordination is performed by receiving from or sending to the first base station one or more measurement items for the measurement configuration, and at least one of the measurement items comprises one or more of the following: a value indicating a purpose of a measurement; one or more triggering parameters indicating when the measurement should be performed; and an indication of whether a report should be delivered to the second base station.

[00120] Example 21. The method of any one of examples 12 to 20, wherein one of the first radio access technology or the second radio access technology is a long term evolution technology and an other of the first radio access technology or second radio access technology is a new radio technology.

[00121] Additional examples are as follows.

[00122] Example 22. An apparatus, comprising: [00123] means for coordinating, by a first base station and with a second base station, a joint operation of communication between the first base station, the second base station, and a user equipment, wherein the first base station uses a first radio access technology to communicate with the user equipment and the second base station uses a different, second radio access technology to communicate with the user equipment, and wherein the coordinating determines a measurement configuration to be used by the user equipment to measure one or more cells of the second base station;

[00124] means for sending by the first base station the measurement configuration to the user equipment; and

[00125] means for communicating, as part of the joint operation, by the first base station with the user equipment.

[00126] Example 23. The apparatus of example 22, further comprising means for performing any of the methods of examples 2 to 11.

[00127] Example 24. An apparatus, comprising:

[00128] means for participating in coordination, controlled by a first base station and participated in by a second base station, of a joint operation of communication between the first base station, the second base station, and a user equipment, wherein the first base station uses a first radio access technology to communicate with the user equipment and the second base station uses a different, second radio access technology to communicate with the user equipment, and wherein the coordination determines a measurement configuration to be used by the user equipment to measure one or more cells of the second base station; and

[00129] means for communicating, as part of the joint operation, by the second base station with the user equipment.

[00130] Example 25. The apparatus of example 24, further comprising means for performing any of the methods of examples 13 to 21.

[00131] Example 26. A communication system, comprising an apparatus according to example 22 or 23 and an apparatus according to example 24 or 25.

[00132] Example 27. A computer program, comprising code for performing any of the methods of examples 1 to 23, when the computer program is run on a processor.

[00133] Example 28. The computer program according to example 27, wherein the computer program is a computer program product comprising a computer-readable medium bearing computer program code embodied therein for use with a computer.

[00134] Example 29. An apparatus, comprising:

[00135] at least one processor; and

[00136] at least one memory including computer program code,

[00137] the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus to perform operations comprising: [00138] coordinating, by a first base station and with a second base station, a joint operation of communication between the first base station, the second base station, and a user equipment, wherein the first base station uses a first radio access technology to communicate with the user equipment and the second base station uses a different, second radio access technology to communicate with the user equipment, and wherein the coordinating determines a measurement configuration to be used by the user equipment to measure one or more cells of the second base station;

[00139] sending by the first base station the measurement configuration to the user equipment; and

[00140] communicating, as part of the joint operation, by the first base station with the user equipment.

[00141] Example 30. The apparatus of example 29, wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to perform operations for performing any of the methods of examples 2 to 11.

[00142] Example 31. An apparatus, comprising:

[00143] at least one processor; and

[00144] at least one memory including computer program code,

[00145] the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus to perform operations comprising:

[00146] participating in coordination, controlled by a first base station and participated in by a second base station, of a joint operation of communication between the first base station, the second base station, and a user equipment, wherein the first base station uses a first radio access technology to communicate with the user equipment and the second base station uses a different, second radio access technology to communicate with the user equipment, and wherein the coordination determines a measurement configuration to be used by the user equipment to measure one or more cells of the second base station; and

[00147] communicating, as part of the joint operation, by the second base station with the user equipment.

[00148] Example 32. The apparatus of example 31, wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to perform operations for performing any of the methods of examples 13 to 21.

[00149] Embodiments herein may be implemented in software (executed by one or more processors), hardware (e.g., an application specific integrated circuit), or a combination of software and hardware. In an example embodiment, the software (e.g., application logic, an instruction set) is maintained on any one of various conventional computer -readable media. In the context of this document, a "computer-readable medium" may be any media or means that can contain, store, communicate, propagate or transport the instructions for use by or in connection with an instruction execution system, apparatus, or device, such as a computer, with one example of a computer described and depicted, e.g., in FIG. 1. A computer-readable medium may comprise a computer-readable storage medium (e.g., memories 125, 155, 171 or other device) that may be any media or means that can contain, store, and/or transport the instructions for use by or in connection with an instruction execution system, apparatus, or device, such as a computer. A

computer-readable storage medium does not comprise propagating signals.

[00150] If desired, the different functions discussed herein may be performed in a different order and/or concurrently with each other. Furthermore, if desired, one or more of the above-described functions may be optional or may be combined.

[00151] Although various aspects of the invention are set out in the independent claims, other aspects of the invention comprise other combinations of features from the described embodiments and/or the dependent claims with the features of the independent claims, and not solely the combinations explicitly set out in the claims.

[00152] It is also noted herein that while the above describes example embodiments of the invention, these descriptions should not be viewed in a limiting sense. Rather, there are several variations and modifications which may be made without departing from the scope of the present invention as defined in the appended claims.

[00153] The following abbreviations that may be found in the specification and/or the drawing figures are defined as follows:

3GPP third generation partnership project

5G fifth generation

dB decibels

DC dual connectivity

eLTE evolved LTE

eNB (or eNodeB) evolved Node B (e.g., an LTE base station)

GHz gigaHertz

HetNet heterogeneous network

ID identification

VF interface

IW interworking

LTE long term evolution

MC measurement coordination

Meas. measurement

MeNB master eNB (also called LTE eNB)

MME mobility management entity

ms milliseconds

NCE network control element NG next generation

NR new radio

NAV network

RAN radio access network

RAT radio access technologies

RRC radio resource control

RRH remote radio head

RSRP reference signal received power

RSRQ reference signal received quality

Rx receiver

SeNB secondary eNB (also called NR eNB)

SGW serving gateway

S-RLF secondary radio link failure

TSG technical specification group

Tx transmitter

UE user equipment (e.g., a wireless, typically mobile device)

WG working group

Claims

CLAIMS What is claimed is:

1. A method, comprising:

coordinating, by a first base station and with a second base station, a joint operation of communication between the first base station, the second base station, and a user equipment, wherein the first base station uses a first radio access technology to communicate with the user equipment and the second base station uses a different, second radio access technology to communicate with the user equipment, and wherein the coordinating determines a measurement configuration to be used by the user equipment to measure one or more cells of the second base station; sending by the first base station the measurement configuration to the user equipment; and communicating, as part of the joint operation, by the first base station with the user

equipment.

2. The method of claim 1, further comprising the first base station receiving, based on the measurement configuration, measurement reports from the user equipment comprising one or more measurements of radio conditions at the user equipment based on one or more signals from the second base station, and the first base station reporting the one or more measurements to the second base station.

3. The method of claim 2, wherein:

the measurement reports further comprise one or more first measurements from the user equipment of radio conditions at the user equipment based on one or more signals from the first base station;

the one or more measurements of the radio conditions at the user equipment based on the one or more signals from the second base station are second measurements; and the first base station filters out the one or more second measurements prior to forwarding the one or more second measurements to the second base station.

4. The method of claim 3, wherein:

the first base station receives the measurement reports at a periodicity;

the measurement configuration has a difference in periodicity between a first periodicity for the one or more first measurements and a second periodicity for the one or more second measurements; and the forwarding the one or more second measurements to the second base station occurs based on the second periodicity for the one or more second measurements.

5. The method of claim 1, wherein the measurement configuration includes a configuration for the user equipment to send measurement reports only to the second base station, and wherein the method further comprises receiving by the first base station measurement reports from the second base station of one or more measurements of radio conditions at the user equipment based on one or more signals from the first base station.

6. The method of claim 1, further comprising the first base station receiving, based on the measurement configuration, measurement reports from the user equipment comprising one or more measurements of radio conditions at the user equipment based on one or more signals from the first base station.

7. The method of any one of claims 1 to 6, wherein coordinating further comprises:

sending from the first base station to the second base station a request for joint operation, wherein the request comprises a proposed measurement configuration to be used by the user equipment to measure radio conditions at the user equipment for the second base station;

receiving at the first base station a response from the second base station comprising a second proposed measurement configuration, the second proposed measurement configuration comprising either the proposed measurement configuration or a modified measurement configuration;

determining a final measurement configuration based on the second proposed measurement configuration; and

sending a message to the user equipment indicating the final measurement configuration.

8. The method of claim 7, wherein the second proposed measurement configuration

comprises the modified measurement configuration, and modifications to the proposed measurement configuration comprise one or more of the following: one or more additional events have been added; one or more events have been deleted; and one or more parameter changes have been performed to one or more events.

9. The method of one of claims 7 or 8, wherein the final measurement configuration further comprises indication of measurement configuration to be used by the user equipment to measure radio conditions at the user equipment for the first base station.

10. The method of any one of claims 1 to 9, wherein coordinating comprises communicating one or more measurement items for the measurement configuration between the first and second base stations, and at least one of the measurement items comprises one or more of the following: a value indicating a purpose of a measurement configuration to be used by the user equipment; one or more triggering parameters indicating when the measurement should be performed; and an indication of whether a report for the measurement should be delivered to the second base station.

11. The method of any one of claims 1 to 10, wherein one of the first radio access technology or the second radio access technology is a long term evolution technology and an other of the first radio access technology or second radio access technology is a new radio technology.

12. A method, comprising:

participating in coordination, controlled by a first base station and participated in by a second base station, of a joint operation of communication between the first base station, the second base station, and a user equipment, wherein the first base station uses a first radio access technology to communicate with the user equipment and the second base station uses a different, second radio access technology to communicate with the user equipment, and wherein the coordination determines a measurement configuration to be used by the user equipment to measure one or more cells of the second base station; and

communicating, as part of the joint operation, by the second base station with the user equipment.

13. The method of claim 12, further comprising the second base station receiving, based on the measurement configuration, measurement reports from the user equipment comprising one or more measurements of radio conditions at the user equipment based on one or more signals from the first base station, and the second base station forwarding the one or more measurements to the first base station.

14. The method of claim 13, wherein:

the one or more measurements of the radio conditions at the user equipment based on the one or more signals from the first base station are first measurements;

the measurement reports further comprise one or more second measurements from the user equipment of radio conditions at the user equipment based on one or more signals from the second base station; and the second base station filters out the one or more first measurements prior to forwarding the one or more first measurements to the first base station.

15. The method of claim 14, wherein:

the second base station receives the measurement reports at a periodicity;

the measurement configuration has a difference in periodicity between a first periodicity for the one or more first measurements and a second periodicity for the one or more second measurements; and

the forwarding the one or more first measurements to the first base station occurs based on the first periodicity for the one or more first measurements.

16. The method of claim 12, further comprising receiving, based on the measurement

configuration, measurement reports from the first base station of one or more measurements of radio conditions at the user equipment based on one or more signals from the second base station.

17. The method of claim 12, further comprising the second base station receiving, based on the measurement configuration, measurement reports from the user equipment comprising one or more measurements of radio conditions at the user equipment based on one or more signals from the second base station.

18. The method of any one of claims 12 to 17, wherein participating in the coordination further comprises:

receiving, at the second base station and from the first base station, a request for joint operation, wherein the request comprises a proposed measurement configuration to be used by the user equipment to measure radio conditions at the user equipment for the second base station;

deciding by the second base station whether the proposed measurement configuration is sufficient, and in response to the proposed measurement configuration not being sufficient, modifying the proposed measurement configuration to create a modified measurement configuration;

sending, by the second base station and toward the first base station, a response comprising the second proposed measurement configuration, the second proposed measurement configuration comprising either the proposed measurement configuration or the modified measurement configuration; and

receiving, at the second base station and from the first base station, a final measurement configuration based on the second proposed measurement configuration, and preparing to receive measurement reports based on the final measurement configuration.

19. The method of claim 18, wherein the second proposed measurement configuration

20. The method of any one of claims 12 to 20, wherein the participating in the coordination is performed by receiving from or sending to the first base station one or more measurement items for the measurement configuration, and at least one of the measurement items comprises one or more of the following: a value indicating a purpose of a measurement; one or more triggering parameters indicating when the measurement should be performed; and an indication of whether a report should be delivered to the second base station.

21. The method of any one of claims 12 to 20, wherein one of the first radio access technology or the second radio access technology is a long term evolution technology and an other of the first radio access technology or second radio access technology is a new radio technology.

22. An apparatus, comprising:

means for coordinating, by a first base station and with a second base station, a joint operation of communication between the first base station, the second base station, and a user equipment, wherein the first base station uses a first radio access technology to communicate with the user equipment and the second base station uses a different, second radio access technology to communicate with the user equipment, and wherein the coordinating determines a measurement configuration to be used by the user equipment to measure one or more cells of the second base station;

means for sending by the first base station the measurement configuration to the user equipment; and

means for communicating, as part of the joint operation, by the first base station with the user equipment.

23. The apparatus of claim 22, further comprising means for performing any of the methods of claims 2 to 11.

24. An apparatus, comprising:

means for participating in coordination, controlled by a first base station and participated in by a second base station, of a joint operation of communication between the first base station, the second base station, and a user equipment, wherein the first base station uses a first radio access technology to communicate with the user equipment and the second base station uses a different, second radio access technology to communicate with the user equipment, and wherein the coordination determines a measurement configuration to be used by the user equipment to measure one or more cells of the second base station; and

means for communicating, as part of the joint operation, by the second base station with the user equipment.

25. The apparatus of claim 24, further comprising means for performing any of the methods of claims 13 to 21.

26. A communication system, comprising an apparatus according to claim 22 or 23 and an apparatus according to claim 24 or 25.

27. A computer program, comprising code for performing any of the methods of claims 1 to 23, when the computer program is run on a processor.

28. The computer program according to claim 27, wherein the computer program is a computer program product comprising a computer-readable medium bearing computer program code embodied therein for use with a computer.