Method for automatic optimization of radio parameters of base stations; associated radio network and optimization system

Description

[0001] The present invention relates to the optimization of radio resources between neighboring cells of a radiocommunication network.

[0002] In a communication network, particularly in the radio access network - RAN ("Radio Access Network"), a mechanism for optimizing radio resources between neighboring cells is implemented. This will be referred to below as the SON ("Self Optimizing Network") mechanism.

[0003] When deploying a network, the base stations of two neighboring cells are configured to coordinate their radio resources. This configuration includes choosing a particular SON mechanism from a plurality of possible SON mechanisms, and defining the parameters of the chosen SON mechanism.

[0004] For example, the 3GPP TS 36.300 or 3GPP TR 36.902 normative document defines SON mechanisms that can be considered for the case of LTE (“Long-Term Evolution”) networks.

[0005] Even if some SON mechanisms, such as SFR ("Soft Frequency Reuse") or ABS ("Almost Blank Subframe") interference management mechanisms, allow automatic redefinition of some of their parameters without human intervention, the fact remains that the "a priori" choice of the SON mechanism implemented in a network remains specific to a network whose topology is fixed, that is to say for which the base stations are immobile, the neighborhood of a base station not being modified over time.

[0006] Currently, radio resource optimization for the case of mobile base stations (or more generally, whose position is not known a priori, as in a classic cellular network) has not received any treatment.

[0007] There is therefore a need for an automatic optimization system allowing dynamic configuration of the SON mechanism implemented in a network depending on the network topology at the current time.

[0008] Document US 2017 / 251404 A1 describes a method in which a first orchestrator associated with a static macro base station communicates with a second orchestrator associated with a mobile base station, which moves in the coverage area of ​​the macro base station, to adjust the parameters of the macro base station and those of the mobile base station. The macro base station is backed by a database which is updated with the adjusted transmission power and topological information of the mobile base station.

[0009] Furthermore, the normative document "3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 (Release 16)", 3GPP DRAFT; 36300-G60, 3RD GENERATION PARTNERSHIP PROJECT (3GPP), July 6, 2021, XP052030849, discloses an Xn communications link between two base stations.

[0010] The purpose of this invention is to meet this need.

[0011] For this, the invention relates to an automatic optimization method, a radiocommunication network and an optimization system according to the appended claims.

[0012] The invention and its advantages will be better understood upon reading the following detailed description of a particular embodiment, given solely as a non-limiting example, this description being made with reference to the appended drawings in which: [ Fig 1 ] There figure 1 is a schematic representation of an infrastructure allowing the implementation of the method according to the invention; and, [ Fig 2 ] There figure 2 is a block representation of the method according to the invention. GENERAL STRUCTURE

[0013] In the following, the description of a preferred embodiment is made within the framework of the 3GPP 5G (5th generation) standard. However, the person skilled in the art knows how to adapt the architecture presented to the case of another radiocommunication standard, in particular the 3GPP 4G (4th generation) standard and its evolutions (such as 3GPP LTE "Long Term Evolution"), or even future standards, in particular 3GPP 6G (6th generation).

[0014] Referring to the figure 1 , a radiocommunication infrastructure comprises a first radiocommunication network 100, a second radiocommunication network 200, and a plurality of user equipments - UEs (User Equipment). For example, on the figure 1 , six EUs are represented. They are respectively referenced from 1 to 6.

[0015] The first 100 network is a radiocommunication network according to the 3GPP 5G standard. It includes: a radio access network - RAN ("Radio Access Network") 110, integrating a plurality of base stations - gNB ("g-Node B"). A gNB allows a UE to connect, by means of a radio link, to the first network 100. For example, on the figure 1 , two gNBs 112 and 114 are represented. Associated with gNB 112 is a coverage 113 and associated with gNB 114 is a coverage 115. Since the coverages 113 and 115 are adjacent, the gNBs 112 and 114 are said to be neighbors. In the RAN, two gNBs are in communication via a standardized interface, called an Xn link. a core network - 5GC ("5G Core") 120. Schematically, the 5GC 120 comprises in particular one or more devices performing access management functions - AMF ("Access and Mobility Management") and / or user plane functions - UPF ("User Plane Function"). For example, on the figure 1 , the 5GC 120 comprises two AMF / UPF devices, respectively referenced 122 and 124. Each gNB of the RAN 110 is in communication with each AMF / UPF device of the 5GC through a standardized interface, called NG link. a data network - SDDC ("Software-defined data center") 130, which is a network, preferably private and secure, comprising several virtualized services. an orchestration system 140, which comprises a service orchestrator 141 supervising a plurality of specialized orchestrators, such as for example a network orchestrator 142, a security orchestrator 143 and an IT orchestrator 144.

[0016] The service orchestrator 141 allows, through the specialized orchestrators, the allocation of physical and / or virtual resources available on the first network 100 according to the needs of the users (in accordance with their respective profiles).

[0017] Physical resources include, for example, SDDC computing power, SDDC working memory volumes, network bandwidth values, network address translation (NAT) capabilities through a firewall, etc.

[0018] Virtual resources include, for example, virtualized bricks, each corresponding to an application enabling specific processing to be carried out on specific data, such as, for example, a deep packet inspection (DPI) application by a firewall, an image processing application by an SDDC application, or an application for compressing a data stream by the network.

[0019] The network orchestrator 142 controls the machines of the 5GC 120 to configure them according to the commands received from the service orchestrator 141. This involves, for example, configuring the routing of a certain type of data flow associated with an identified user to ensure a certain bandwidth.

[0020] The security orchestrator 143 controls the machines of the first network 100, in particular the firewall-type machines, to configure them according to the commands received from the service orchestrator 141. This involves, for example, filtering the circulation of data of an authenticated user according to the privileges indicated in a profile of this user kept up to date by the orchestration system.

[0021] The IT orchestrator 144 controls the machines of the SDDC 130 to configure them according to the commands received from the service orchestrator 141. This involves, for example, instantiating a particular virtual application based on an identified need, reserving a certain memory resource and a certain computing resource for it on the machines of the SDDC 130, and possibly decommissioning a particular instance when it is no longer used.

[0022] According to the invention, the first network 100 comprises an optimization system 150 interfaced with the RAN 110.

[0023] The optimization system 150 comprises, on the orchestration system 140 side, an optimization orchestrator 152, as an additional specialized orchestrator, and advantageously a catalog of objectives 154.

[0024] The optimization system 150 comprises, on the RAN 110 side, a self-configuration controller 156 and an analysis module 158, for determining the topology and traffic on all the cells of the RAN 110. Preferably, the module 158 comprises a unit 159 dedicated to determining the current topology of the RAN 110 and a unit 157 dedicated to the current traffic on the RAN 110.

[0025] The second network 200 is identical or similar to the first network 100. The second network is advantageously lighter (less equipment) than the first network so that it can be carried on board a vehicle.

[0026] A component of the second network similar to a component of the first network is identified by a reference number which corresponds to the reference number used to identify this similar component of the first network, increased by one hundred.

[0027] Thus, the second network 200 comprises a RAN 210, a 5GC 220 and an orchestration system 240.

[0028] The RAN comprises a 212 gNB associated with a 213 cell.

[0029] The 5GC 220 includes an AMF / UPF 222 device. The gNB 212 is connected to the AMF / UPF 222 device via an NG link.

[0030] The orchestration system 240 comprises a service orchestrator 241 supervising a plurality of specialized orchestrators, such as for example a network orchestrator 242 and a security orchestrator 243.

[0031] According to the invention, the second network 200 comprises an optimization system 250 interfaced with the RAN 210.

[0032] The optimization system 250 comprises, on the orchestration system 240 side, an optimization orchestrator 252, as an additional specialized orchestrator, and an objective catalog 254.

[0033] The optimization system 250 comprises, on the RAN 210 side, a self-configuration controller 256 and an analysis module 258 comprising a unit 259 for determining the current topology of the RAN 210 and a unit 257 for determining the current traffic on the RAN 210.

[0034] The second network 200 is carried on board a carrier vehicle.

[0035] During the movement of the carrier vehicle, cell 213 of the second network 200 enters cell 113 of the first network. In the following, cell 113 will be called the first cell or deployed cell, while cell 213 will be called the second cell or incoming cell.

[0036] During the implementation of the method, as will be described below, a link Xn 10 is established between the gNBs 112 and 212 of the deployed 113 and incoming 213 cells.

[0037] Furthermore, a federation link 11 is considered to be established between the first and second networks 100 and 200. The link 11 supports an orchestration plan. On the figure 1 , the link 11 schematically connects the first and second service orchestrators 141 and 241. In reality, this link can take different forms, such as for example a link between a first gateway of the first core network 5GC 120 and a second gateway of the second core network 5GC 220. This link can include a satellite portion. The manner of establishing such a link is outside the scope of the present application. GENERALITIES AND DEFINITIONS

[0038] Generally speaking, the self-configuration of SON mechanisms involves choosing a general optimization objective, then determining a current strategy to achieve the general objective given the current network topology, the chosen strategy, which defines the variables and / or parameters to be optimized, leading to the deployment and configuration of a particular SON mechanism.

[0039] More specifically, a "goal" is a radio performance indicator. For example, a goal might be optimizing cell coverage or optimizing cell capacity: maximizing average throughput for users, maximizing a certain fraction of user throughput, minimizing cell-to-cell interference, or ensuring that a certain percentile of the Reference Signal Received Power (RSRP) measurements made by a user terminal and a base station are above a threshold.

[0040] A "strategy" is a specific optimization method for achieving the desired objective. For example, the optimization method may consist of simply turning off the incoming cell, coordinating the radio resources of the cells, redistributing the load between the incoming and deployed cells, adjusting the antenna angle ("tilt") of the base stations of the incoming and deployed cells, or a combination of these basic strategies.

[0041] A strategy is characterized by a radio allocation profile (or radio transmission mode). The radio allocation profile defines the characteristics of radio resource allocation according to one or more dimensions (frequency, time, space, and / or power), for example according to user categories. Thus, for example, the allocation profile, defined according to the space, frequency, and power dimensions, may consist of transmitting with amplified power but over a limited (configurable) spectral zone for users at the edge of the cell and with low power for other users. For example, the radio allocation profile, defined on the time and power dimensions, may consist of transmitting at low power over time slots to be defined (configurable).

[0042] A radio allocation profile is then dynamically configured or reconfigured, taking into account traffic and / or network topology information at the current time. SPECIAL STRUCTURE OF THE SOUND ORCHESTRATOR

[0043] To do this, the optimization orchestrator, 152 or 252, of an orchestration system, 150 or 250, associated with a network, 100 or 200, is responsible for defining an optimization strategy.

[0044] Preferably, the definition of a strategy is carried out from one or more radio performance objectives selected by an operator of the associated network, for example from the catalog of objectives, 154 or 254, which comprises a plurality of predefined radio performance objectives.

[0045] The definition of a strategy is carried out from information relating to the current topology of the associated network, 100 or 200. This topological information is returned by the associated analysis module, 158 or 258.

[0046] The analysis module, 158 or 258, is configured to detect, at each instant, the topology of the network, namely the positioning and the neighborhood of the base stations of the associated network and the spatial distribution of the traffic.

[0047] For example, the orchestration system being connected to each base station of the RAN by suitable communication interfaces allowing a configuration plan ("management plane") to be established, the analysis module collects information relating to each base station of the network, such as the range of the base station, the list of neighboring cells, the position of the base station (measured by a satellite positioning device - GPS equipping the station), and possibly the speed of movement and acceleration of the base station. For example again, the analysis module also collects natively collected radio measurements, such as CQI ("Channel Quality Indicator") or RSRP measurements, reported by the UEs connected to the different base stations of the network.

[0048] The analysis module can then establish the spatial distribution of the base stations, and for each base station, the spatial distribution of the UEs. For example, for a given base station, the number of UEs at the cell center served by this base station and the number of UEs at the edge of the cell (i.e. ultimately the UEs in good or bad radio conditions).

[0049] The self-configuration controller, 156 or 256, of an orchestration system, 150 or 250, associated with a network, 100 or 200, automates the configuration of the base station(s) of the associated network to achieve the radio allocation profile defined by the strategy received from the optimization orchestrator 152, 252.

[0050] The self-configuration controller, 156 or 256, also takes as input the topological information delivered at the current time by the associated analysis module, 158 or 258. Any modification of this topological information causes a reconfiguration of the radio allocation profile to be carried out.

[0051] The self-configuration controller, 156 or 256, therefore performs the effective allocation of radio resources according to the strategy indicated from the traffic and topology information of the associated network. PROCESS

[0052] A preferred embodiment of the method for automatic optimization of radio parameters according to the invention will now be presented, with reference to the figure 2 , within the framework of a partial overlap of the coverage areas of the deployed cell 113 and the incoming cell 213.

[0053] The method 300 comprises a preparatory phase 310, which consists, on the first network 100 side, of detecting the entry of the second cell 213 into the first cell 113, and in parallel, on the second network 200 side, of detecting the entry of the first cell 113 into the second cell 213. The preparatory phase ends, if successful, with the establishment of an interface Xn 10 between the first gNB 112 and the second gNB 212. There is therefore a direct connection of the base stations of the incoming and deployed cells.

[0054] More precisely, on the first network 100 side, the preparatory phase 310 consists firstly, in a step 312, of ensuring the discovery of the incoming cell. The first gNB 112 of the first cell 113 regularly requests the connected UEs (2 to 5 on the figure 1 ) to carry out measurements on any new cells in the vicinity of these UEs.

[0055] This measurement procedure is specified, for example, by the TS 36.331 standard. It uses the broadcasting by each cell of a physical cell identifier - PCI (Physical Cell Identifier).

[0056] Each UE responds to the first gNB 112 by sending a measurement report.

[0057] The measurement report of the UE 5, in the overlap area of ​​the first and second cells, 113, 213, then includes information allowing the first gNB 112 to detect the entry of the second cell 213.

[0058] This report includes the PCI of the second cell 213.

[0059] This report does not, however, include the NCGI of the second cell 213. The NCGI (“NR Cell Global Identity”) is a generic identifier for cells in a 5G network.

[0060] However, having the NCGI of the second cell 213 advantageously makes it possible to recognize the second network 200 and to know whether the first network 100 is authorized to interconnect with the second network 200 at the base stations.

[0061] Thus, preferably, the first gNB 112 then requests the UE 5 to read and report to it the NCGI of the second cell 213.

[0062] If the reported NCGI matches an authorized network, the preparatory phase 310 continues with a step 314 aimed at resolving possible PCI conflicts.

[0063] According to the TS 36.300 standard, each base station maintains a neighbor relation table - NRT ("neighbor relation table") containing the list of neighboring cell identifiers - TCI ("Target Cell Identifiers").

[0064] Thus, the first gNB 112 maintains a first neighborhood table of the first cell 113. Each cell in this list is associated with a PCI and an NCGI.

[0065] If the PCI of the second cell 213 is already in the first neighborhood table, and if the NCGI associated with this PCI in the first neighborhood table is different from that reported by the UE 5, a conflict is detected by the first gNB 112. In other words, the PCI of the second cell 213 is already used by another cell neighboring the first cell 113.

[0066] If the PCI of the second cell 213 is not in the first neighbor table, the candidate incoming cell is queried for connectivity information and addition to the first neighbor table. If the second cell 213 responds favorably, it is added to the first neighbor cell list. However, a detection step 313 and a conflict detection step 315, similar to step 312 and step 314 respectively, being implemented by the second network 200, the second gNB 212 may have detected a conflict, the PCI of the first cell 113 already being in a second neighbor table maintained by the second gNB 212 (the PCI of the first cell 113 already being used by another neighboring cell of the second cell 213). In this case, the second cell 213 may respond unfavorably to the request from the first cell 113 so that the second cell 213 is not added to the first neighborhood table.

[0067] Optionally, dynamic PCI reassignment processes may be implemented in the first network and / or the second network in the event of a conflict to modify the PCI of the cell(s) and allow them to be registered in the neighbor table of one or more base stations.

[0068] In the event of successful addition of the incoming cell to the neighbor table of the deployed cell at the end of step 314 and of the deployed cell to the neighbor table of the incoming cell at the end of step 315, the preparatory phase 310 continues with a step 316 consisting of establishing the connection interface between the first gNB 112 and the second gNB 212 by means of the link Xn 10. Advantageously, this step implements a process of mutual authentication of the two gNBs. The establishment of this link makes it possible to establish data communication plans between the first and second networks 100 and 200.

[0069] Then, in a step 318, the optimization systems 150 and 250 enter into negotiation, via the federation link 11, to determine which of the two optimization systems will take control for the rest of the implementation of the method, i.e. become the master optimization system.

[0070] For example, each network is assigned a hierarchy level identifier. The second network has a low hierarchy level and the first network has a high hierarchy level. The hierarchy levels are shared between the optimization systems and then compared with each other to determine which optimization system should become the master. In this description, the orchestration system 150 becomes the master.

[0071] Preferably, the method 300 then comprises a transient phase 320, which aims to reduce the impact of the incoming cell on the performance of the deployed cell. This transient phase 320 lasts until the immobilization of the vehicle carrying the second network 200 or until the start of the optimization phase 330, which is the next phase of the method 300.

[0072] During this transient phase 320, in step 322, the first gNB 112 requests, on the link Xn, the second gNB 212 to gradually reduce its transmission power in order to preserve the communications in progress between the first base station 112 and the UEs 2 to 5. Consequently, at each time step, the second gNB 212 decreases its transmission power by a predefined number of decibels (dBm).

[0073] During this gradual decrease, at each time step, the first gNB 112 analyzes (step 324) the impact of the decrease in power on the interference based for example on the statistics on the number of retransmissions (“HARQ process”) or other statistics impacted by the interference between cells.

[0074] When the statistic returns to an acceptable level, the first gNB 112 sends a request to the second gNB 212 to stop the decrease in its power (step 326).

[0075] Then the process 300 enters the optimization phase 330, which makes it possible to put in place the best possible SON mechanism to optimize the combined performance of the deployed and incoming cells.

[0076] In step 331, a current objective has been preselected, offline, by an operator of the first network 100 in the catalog 154. This is for example an objective consisting of coordinating the use of the resources of the cells on an area of ​​interest so as to minimize interference on the same channel while allocating the resources necessary to satisfy the objective sought. This objective aims for the best compromise between limiting interference between the two cells, by avoiding reusing the same radio resources, while adapting the spectral band to the traffic needs.

[0077] In step 332, the first analysis module 158 is periodically implemented in order to update the topology of the network at the current time. The second gNB 212 being connected by the link Xn to the first gNB 112, the information relating to the second cell 213 is also taken into account by the first analysis module 158 to determine the current topology of the network.

[0078] In step 334, following a modification of the current topology, the first optimization orchestrator 152 is executed in order to select a suitable strategy taking into account the current objective and the new current topology of the network, as indicated by the first analysis module 158.

[0079] In one embodiment, an optimization orchestrator module implements a plurality of logical rules to, based on the current topology and the objective to be met, define the optimal strategy. Alternatively, an optimization orchestrator module implements a machine learning algorithm, for example by supervision, making it possible to decide on the optimal strategy based on the inputs that are the current topology and the objective to be met.

[0080] The first optimization orchestrator 152 transmits the selected strategy (i.e. a radio allocation profile) to the self-configuration controller 156 of the first network 100, but also to the second self-configuration controller 256 of the second network 200 (via the federation link 11).

[0081] While the preceding steps are carried out at the level of the orchestrator system 140, considered as the master system, the following steps are carried out at the level of the first RAN 110 and the second RAN 120. Their implementation can be decoupled from the preceding steps, in particular when there is no modification of the network topology, but only a modification of the traffic, requiring a new configuration of the radio allocation profile without changing the nature of this profile.

[0082] In step 335, the first analysis module 158 regularly updates the traffic information on the first network 100 at the current time.

[0083] In step 336, the first self-configuration controller 156 implements a model to carry out the strategy received from the first optimization orchestrator 152, taking into account the traffic information at the current time delivered by the first analysis module 158 to dynamically determine the parameters of the radio allocation profile of the received strategy.

[0084] At the same time, step 337, the second analysis module 258 regularly updates the traffic information on the second network at the current time.

[0085] In step 338, the second self-configuration controller 158 implements a model to carry out the strategy received from the first optimization orchestrator 152, taking into account the traffic information at the current time delivered by the second analysis module 258 to dynamically determine the parameters of the radio allocation profile of the received strategy. EXAMPLE

[0086] In a simple illustrative example, the common goal is to provide coverage to X% of users or increase capacity by Y%.

[0087] As topological information, for example, the distance between the second base station 212 and the first base station 112 is taken into account.

[0088] If the distance is small (the second base station operating close to the first base station), the strategy adopted may be to switch off the second base station to ensure coverage. The self-configuring controller(s) are then commanded to implement this strategy.

[0089] If the distance is medium (the second base station operating on the edge of the first cell associated with the first base station), the strategy chosen may be, to ensure the extension of the coverage, to implement an ABS procedure ("almost blank subframe") with CRE ("cell range expansion"). The self-configuration controller(s) are then commanded to implement this strategy.

[0090] Finally, if the distance is large (the second base station operating at a distance from the first base station), the strategy adopted may be, to ensure the extension of the coverage, to implement a power control procedure with SFR (“Soft Frequency Reuse”). The self-configuration controller(s) are then commanded to put this strategy into practice. A self-configuration controller then adjusts the parameters of the radio resource allocation profile to: transmit with high power but in a reduced and cell-specific frequency interval so as not to interfere with the edge of neighboring cells, in order to reach the UEs at the edge of the cell - CEU (“Cell Edge Users”); transmit with reduced power but in an extended spectral band for the UEs at the center of the cell - CCU (“Cell Center Users”),

[0091] In another illustrative example, the common goal is to distribute the load.

[0092] The strategy adopted may then be a load redistribution between deployed and incoming cells with power reduction in order to trigger the inter-cell handover of all or part of the UEs connected to the second cell 213 to the first cell 113. The self-configuration controller(s) implement this strategy by adapting the parameters of the corresponding radio allocation profile in order to reduce the transmission power of the second gNB 212. The load of the first cell 113 increases and, consequently, the required bandwidth increases. There is therefore a compromise to be established, knowing that the reduction of the interference of the second cell 213 on the first cell 113 makes it possible to improve the channel quality indicator - CQI ("Channel Quality Indicator") and therefore to alleviate the constraint on the necessary bandwidth despite the increase in the load for the first cell.Thus, when the load at the edge of the second cell 213 is low, reducing the power on the second cell 213 will cause users at the edge of the second cell 213 to switch to the first cell 113. The transmission power of the second cell 213 is reduced so as to only cover users in the center of the second cell 213. The interference caused by the second cell 213 on the first cell 113 is significantly reduced. VARIANTS

[0093] If the case of a 5G network was more particularly presented in the previous example, the person skilled in the art will know how to adapt this teaching to the case of other types of radiocommunication networks. For example, in 4G / LTE, instead of an Xn link between the deployed and incoming base stations, an X2 or S1 link will be established.

[0094] If in the preferred embodiment, the case of the superposition of two cells of mobile base stations relative to each other and belonging to two different networks but federated with each other, the invention applies more generally to the superposition of two cells of mobile base stations relative to each other belonging to the same network, or PLMN ("Public Land Mobile Network"), the topology of which evolves over time and for which the optimization mechanisms must be adapted in real time.

[0095] While the present description has been made for the case of the entry of a second cell into a first cell, it also applies to the exit of a second cell from a first cell, or to any evolution of the positions and / or the relative coverages of the two cells. The method according to the invention makes it possible to adjust the parameters of the radio optimization mechanisms of a cell during any evolution of its radio environment. BENEFITS

[0096] The invention is therefore a solution that allows the radio allocation parameters of the base stations of one or more RAN(s) whose topology evolves over time to be self-configured, in order to optimize the performance of the base stations according to a global objective that is itself configurable. This self-configuration is carried out without "a priori" knowledge of the network topology. It is therefore necessary to implement a means of automatically discovering this topology.

[0097] Those skilled in the art will understand that the present invention addresses the problem of the impossibility of planning deployment (the concept of RNP - "Radio Network Planning") or of optimizing radio parameters (the concept of RNO - "Radio Network Optimization") insofar as it is not known a priori what the neighborhood of a particular base station will be, nor what the relative trajectory followed by a base station belonging to the neighborhood of said particular base station will be.

[0098] The structure of the optimization system 150 based on two units, respectively the optimization orchestrator and the self-configuration controller, makes it possible to carry out a slow loop (with execution of steps 312 to 334 during the modification of the topology to determine a strategy adapted by the orchestrator), and a faster loop (readjustment by the self-configuration controller of the network configuration to carry out the selected strategy) taking into account the traffic or any change in the radio conditions on the network.

[0099] Alternatively, the determination of a new strategy or network reconfiguration can be triggered not automatically (when changing the network topology), but upon request from an operator.

Claims

1. A method (300) executed by an optimization system (150) for automatically optimizing the radio parameters of a first base station (112) and of a second base station (212), the first base station (112) belonging to a first radio communication network (100) and providing coverage on a first cell (113) and the second base station (212) belonging to the first radiocommunication network or a second radiocommunication network (200) and providing coverage on a second cell (213), the second base station being mobile relative to the first base station, the method consisting in: - during a change in the overlap of the first cell (113) by the second cell (213), updating a first neighborhood table kept up to date by the first base station (112) with information from the second cell (213); - updating (333), by a first analysis module, a current topology of the radio coverage, namely the positioning and the neighborhood of the base stations; - determining (334), by means of an optimization orchestrator (152), a current strategy to be implemented from the updated current topology, the current strategy corresponding to a radio allocation profile of the first base station and the second base station; - evaluating (335, 337), by a second analysis module, current traffic of the radio coverage; and - configuring (336, 337), by means of a self-configuration controller, the radio parameters of the first base station and of the second base station according to the current strategy, according to the current traffic, the method being characterized in that, upon an evolution corresponding to the entry of the second cell into the first cell, to add the second cell (213) to the first neighborhood table kept up to date by the first base station (112), the method (300) comprises a detection step (312) for detecting, via the user equipment item(s) connected to the first base station (112), the second base station (212), an identifier conflict resolution step (314) in the event that the identifier of the second cell (213) is already present in the first neighborhood table kept up to date by the first base station (112), and a step of establishing (316) an interface link (10) between the first and second base stations.

2. The method according to claim 1, wherein to determine the current strategy, the optimization orchestrator selects the current strategy from among: a shutdown of the second base station; an allocation of radio resources on a temporal plane, a frequency plane, a power plane and / or a spatial plane; a redistribution of a load between the first and second cells; an adjustment of an angle of a beam of an antenna fitted to the first base station and / or the second base station.

3. The method according to claim 1 or claim 2, comprising a step of choosing an optimization objective, the optimization orchestrator (152) determining a current strategy, not only from the current topology, but also from the previously chosen optimization objective.

4. The method according to claim 3, wherein the optimization objective is selected from a catalog (154).

5. The method according to any one of claims 1 to 4, wherein the current topology is updated from information measured among: a position of each base station, a range of each base station, a movement speed of each base station, an acceleration of each base station.

6. The method according to any one of claims 1 to 5, wherein, after the establishment of an interface link (10) between the first and second base stations, the method (300) includes a step (320) of gradually reducing a transmission power of the second base station (212) to reduce interference between the first cell (113) and the second cell (213).

7. The method according to any one of claims 1 to 6, wherein the interface link (10) between the first and second base stations is an X2 or Xn or S1 type link.

8. A radio communication network (100) comprising a radio access network (110), a core network (120) and an orchestration system (140), characterized in that the radio communication network further comprises an optimization system (150) for implementing an optimization method according to any one of claims 1 to 7, the optimization system (150) comprising, on the orchestration system (140) side, an optimization orchestrator (152) and, on the radio access network (110) side, an auto-configuration controller (156) and one or more analysis module(s) (158) for updating a current topology.

9. An optimization system (150), characterized in that, when it is integrated into a radiocommunication network according to claim 8, it allows the implementation of an optimization method according to any one of claims 1 to 7, the optimization system (150) comprising an optimization orchestrator (152), an auto-configuration controller (156), a first analysis module for determining a current topology of the network and a second module analysis for determining a current traffic on the network.