Telecommunication system

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DESCRIPTION

Management of radio resources in a telecommunication system

Description field

This description refers to radio resource management in a telecommunication system. In particular, the description refers to the management of radio resources in a telecommunication system that provides wireless wide area communications in cellular telecommunication networks.

Background of the invention

Cellular telecommunications networks characteristically provide radio coverage "cells" between communication devices (which are typically mobile) and a core network (with a "downlink" from the core network to the communication device and an "uplink" ”In the opposite direction).

Various radio access technologies (RAT) are implemented: digital cellular networks are currently the most common and these are freely classified as second generation (2G), third generation (3G), fourth generation (4G) technologies, etc. ., depending on whether the RAT achieves effective data communications that meet increasingly challenging requirements. By meeting these requirements, technologies make different uses of the available radio frequency (RF) bandwidth: neighboring cells in 2G technologies, for example, are deployed to use RF bandwidth at different frequencies to avoid interference .

To ensure effective coverage of a large geographic area, a plurality of cells are provided by respective network nodes, variously referred to as base transceiver stations and base stations. The base stations (transceivers) are associated with one or more antenna arrays which in turn establish the respective cells. They are controlled at least in part by other entities in the core network known as controllers (in 3G technologies such as UMTS, these are referred to as radio network controllers, RNCs). More recently, certain categories of base transceiver stations, referred to as eNodeBs or eNBs in the context of LTE, implement both base station functionality and at least some controller functionality. The antenna clusters (and thus often the base stations) are geographically distributed, so that the coverage of each cell typically overlaps that of neighboring cells only at the edge of the cell. RATs aim to ensure that communication devices are provided with continuous coverage, even if they are moving from the coverage of a first cell to that of a second through the cell border region: to do this, they use a reselection technique referred to as "handover" (or "handover"). Handover is described as "smooth" when the procedure allows a transition period during which control and / or user data traffic destined for a given communication device is routed to the device through more than one of the cells. In other words, the device is allowed to "camp" in more than one cell.

Providing communication devices with coverage at the edge of the cell typically requires more network resources; for example, the transmit power needs to be higher on the downlink in order for the RF signal to propagate to the edge of the cell.

The '99 version of the W-CDMA Standard enabled reuse of the same frequency at the edge of the cell with a soft handover (that is, a handover that has a transition phase where a terminal effectively camps both in the cell of origin as the destination).

However, in later versions of RAT 3G, HSDPA, for example, has mainly eliminated in the downlink the concept of soft handoff: data is transmitted from only one cell to the terminal.

In many parts of the world, 4G RATs are deployed (such as those conforming to 3GPP standards known as Long Term Evolution (LTE)). Like these latest versions of 3G, LTE uses universal frequency reuse (where cells far enough apart operate on the same frequency) without soft handoff. Consequently, high levels of interference and low SINRs (signal-to-interference-plus-noise ratio) can be expected near the edge of the cell. This assumes that users at the edge of the cell in LTE (and HSDPA, etc.) require more radio resources (i.e. user plane resource blocks, control channel resource blocks, etc.) than the users closest to serving base transceiver stations (i.e. eNB). Consequently, the potential for the cell to be affected increases when there is an increase in the number and activity of users on / near the border of the cell.

LTE is also specified to handle different types of base transceiver station entities. The requirement for cellular communication coverage is far from uniform across a typical geographic area. In addition, the natural features or the characteristics of the built environment introduce additional restrictions on the operation of the base station entities.

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The most prevalent class of base transceiver station is the wide area eNodeB which provides coverage over a wide geographic area (spanning distances up to 20 km), this is sometimes referred to as the "eNB macro (layer)" type. Such eNBs often provide more than one "cell" or sector.

Base transceiver stations with more limited transmit power than macro eNBs, and typically providing a cell or sector, are known as micro eNBs.

Smaller cells can be provided by devices of even lower power: local area eNBs (or picocell base stations) and home eNBs (or femtocell base stations). The resulting femtocells and picocells are sometimes referred to generally as "small cells." These classes of base transceiver stations are typically used in areas where coverage would otherwise be inadequate or inconvenient to maintain using conventional eNB equipment. The main distinction between home and local area eNBs is that, in the case of home eNBs, the location and control of the device is with the end user rather than the network operator; these devices conventionally offer communication services to a "whitelist" of home users rather than any network subscriber who happens to be in range.

LTE has a hierarchical architecture such that a wide area coverage layer (the macro layer) can overlap or span geographic regions within the coverage of smaller cells (the “micro layer”). However, there may be a preference on behalf of the network operator to have uplink and / or downlink traffic for certain devices delivered to the micro layer; to free capacity in the macro layer for devices that are outside the coverage of the micro layer, for example.

Network operators want to improve the efficiency of using their networks at or near cell edges.

It is known to address the cell border problem:

• Increasing performance at the cell edge, for example by adding increasingly complex software to macro cells to improve cell edge performance (usually within the area of ​​coordinated scheduling between adjacent cells). In certain cases, such as for the CoMP (Coordinated Multiple Point) feature described in 3GPP Version 11, improved cell edge performance brings with it the need for dedicated transmit (Tx) and receive (Rx) antennas. associated with one or more macro eNBs.

• Installing fixed Small Cells (ie local area eNodeBs) to increase system capacity.

The installation of small fixed cells by a network operator brings with it the burden of finding suitable locations, paying the site rent, and deploying additional cables to connect the small fixed cells to other nodes on the network. In addition, the installation and commissioning (including configuration) of small fixed cells takes time: even if a wireless backhaul link is used instead of cables, the small fixed cells need to be installed in a suitable position and configured for their operation at that location. In some cases, this process may include setting up and testing directional antennas associated with such small cell devices that require the skills of a professional radio engineer. Furthermore, when the small cell device fails or otherwise requires servicing the device and the installation site needs to be accessible by the operator: since these devices are normally owned by the network operator but are located on private land and in locations sometimes inaccessible, there are likely to be logistical and practical obstacles to the intervention of one of the operator's engineers.

The LTE standards (3GPP Version 10 (and later)) also describe two additional Radio Access Network entities: relays and repeaters that can be used to address the cell edge problem. Both types of entities provide the coverage extension for a cell of an existing base transceiver station.

A repeater is communicatively linked to a corresponding eNB (usually macro), which has a first antenna within a given cell (the “donor cell”) of the eNB and a second antenna directed towards a coverage area where an extension is required. coverage. In certain cases, a repeater merely retransmits (that is, rebroadcasts) a signal, received on a first frequency, on a second frequency, usually by amplifying the repeated signal. The uplink and downlink signals can thus be carried through repeaters without any need for decoding.

The repeaters specified in Version 10 (and later) of the 3GPP standards decode the (incoming) signal and then recode and retransmit that signal: this new class of repeater is referred to as a "relay".

A relay is also communicatively linked to a corresponding eNB. It also has a first antenna within a given cell (the "donor cell") of the eNB and a second antenna directed towards a target coverage area. However, relays form their own cells and operate in many ways such as

ES 2 838 677 T3 base transceiver stations in their own right. The relays decode the signals from the donor cell, applying any necessary error correction, and make decisions about how radio resources (such as channels within each radio subframe) are allocated.

There are certain network conditions in which individual communication devices in cellular networks have a disproportionately detrimental effect on network performance.

In certain cases, for example, one or more terminals (also called "user equipment" or simply UE) may be near the edge of a serving cell. A small number of active users at the cell edge can consume a high number of cell resources (eg, LTE resource blocks) since the cell edge typically correlates with poor coverage; implying that a high number of resources must be dedicated to the cell edge users to provide a throughput at a given level when compared to the demand for resources by users who are in better radio conditions (that is, far from the cell borders). Serving radio resources for communication devices at the edge of the cell have a higher cost in terms of resource allocation and power usage than a similar device in a cell region closer to a station system service base transceiver (such as an eNodeB).

When cellular networks are deployed, they are often specified with greater capacity than is anticipated to be required by existing communication devices. However, the numbers of communication devices and the demand for increasing network resources mean that the network may be affected by capacity problems on the radio interface more often than is acceptable.

Known approaches to cell edge problems seek to increase the capacity or coverage of the cellular network by adding additional network equipment at locations in the network where cell edge problems regularly occur (or are expected). . Such equipment is normally fixed in one location and requires careful planning.

The network and other performance conditions very often change over time: for example, individual communication devices which, by virtue of their location at the edge of the cell and active use of the network, have a detrimental effect on the network performance at the same time, may, at other times, be idle and not cause such an effect. Furthermore, since UEs are normally mobile, they may have moved out of the affected cell entirely or closer to the base transceiver station equipment serving the cell, in any way, reducing the detrimental effect.

Therefore, it is desirable to ensure that the network can adapt to the presence of dynamic effects on capacity and coverage, and also to provide a system that allows the extension of coverage in a cellular network that can be dynamically deployed without requiring the site. of additional radio equipment near regions of poor radio coverage.

US 2010/167743 A1 refers to techniques for centralized control of a relay operation. A designated network entity (eg, a base station or network controller) can control the operation of relay stations within its coverage area. The network entity may select certain user equipments (UEs) to be relay UEs that can serve as relay stations for other UEs, for example, based on path loss between the UEs and a base station, the EU locations, EU battery power levels, fairness considerations, etc. The network entity may also select a specific relay UE to serve as a relay station for a client UE wishing to communicate with a base station, for example, based on pilot measurements of the relay UEs for the client UE. The network entity may also control the transmission of discovery pilots by the relay UEs and / or the client UEs for retransmission detection.

Document WO 2012/039656 A1 refers to a radio access network comprising a radio access network node and a plurality of wireless devices. At least a first wireless terminal becomes capable of using mixed carrier aggregation. A relay node transmits an unlicensed component carrier or carriers assigned to the first wireless terminal between the radio access network node and the first wireless terminal. Retransmission provided by the relay node can occur either on a downlink and an uplink, or on both a downlink and an uplink.

Compendium of the invention

According to a first aspect of the present description, there is provided a method for determining a functionality of communication devices in a cellular communication network that includes a plurality of communication devices, the method comprising: obtaining at least one measure of the performance of the cellular communication network in a radio coverage component area; determine from the or each performance measure whether performance conditions in the radio coverage component area support the activation of an aggregator facility, said aggregator facility providing radio coverage to the

ES 2 838 677 T3 minus a first communication device within a selected geographic area; determining from the or each performance measure whether a net benefit to network performance in the component area is expected as a result of activating the aggregator facility; controlling the activation of an aggregator functionality in at least a second communication device when performance conditions in the component area of ​​the radio coverage support the activation of the aggregator facility and when a net benefit is expected; and control that an aggregator functionality is not activated when performance conditions in the radio coverage component area support activation of the aggregator facility but no net benefit to network performance is expected, where to determine Whether a net benefit is expected as a result of activating the aggregator facility includes: determining whether the number of first static communication devices located in a part of the component area within range of the at least one second communication device exceeds a threshold number.

As a result, it can be determined whether an aggregator facility (i.e. aggregator layer), in which the radio coverage offered by the macro cell is extended by adding radio coverage from one or more aggregators, can and does should (by some criteria) be initiated. Every second communication device that becomes an aggregator has a functionality by which that device can provide radio coverage in addition to that of the macro cell. This aggregator functionality can be activated as a routine within a client application running on the communication device or as a dedicated functionality, for example.

In certain embodiments, determining whether performance conditions support activation of an aggregator facility includes determining whether the network conditions necessary for activation of an aggregator facility are maintained for a given component area of ​​radio coverage; and determining whether sufficient network conditions to support activation of an aggregator facility are maintained for the component area.

In certain embodiments, determining whether the network conditions necessary for activating an aggregator facility are maintained includes at least one of: determining whether the cell load exceeds a load threshold while the throughput is below a threshold minimum throughput threshold; determining whether the number of users in a cell region exceeds a threshold number of users while the throughput for a given application falls below a minimum throughput threshold; determine if a happiness metric is below a happiness threshold; and / or determining whether the use of control resources exceeds a control resource threshold.

In certain embodiments, sufficient network conditions for activation of an aggregator facility depend on the level of at least one of the following parameters: the number of communication devices in the radio coverage component area; the number of communication devices in the radio coverage component area that have aggregator functionality enabled; the signal-to-interference plus noise ratio, SINR; received signal path loss / received power, RSRP; available radio access technologies, operating frequency and / or carrier bands; the location information of communication devices; the mobility information of communication devices; and the predicted device power profile for the at least one communication device.

In certain embodiments, the at least one second communication device is one of: a user equipment (UE); a machine type communication device (MTC); a repeater; a relay unit; an access point; a wireless station; a small cell station; or a dedicated aggregator facility communication device.

In certain embodiments, determining whether a net benefit is expected as a result of activating the aggregator facility is performed on a macro cell basis for at least one macro cell within the cellular telecommunications network.

According to a second aspect of the present description, a controller entity is provided for determining the functionality of communication devices in a cellular communication network that includes a plurality of communication devices, the controller entity comprising a controller unit configured: to obtain at least one measure of the performance of the cellular communication network in a radio coverage area; to determine from the or each performance measure whether performance conditions in the radio coverage area support the activation of an aggregator facility, said aggregator facility providing radio coverage to at least a first communication device within a selected geographic area; to determine from the or each performance measure whether a net benefit to network performance in the component area is expected as a result of activating the aggregator facility; and to control the activation of an aggregator facility in at least a second communication device when performance conditions in the component area of ​​the radio coverage support activation of the aggregator facility and when a net benefit is expected; to control that an aggregator functionality is not activated when performance conditions in the radio coverage component area support the activation of the aggregator facility, but no net benefit to network performance is expected, where the controlling entity is set up to determine whether a net profit is expected as a result of the

ES 2 838 677 T3 activating the aggregator facility by determining whether the number of first static communication devices located in a part of the component area within range of the at least one second communication device exceeds a threshold number.

In certain embodiments, the controlling entity can be configured to determine whether performance conditions support activation of an aggregator facility by determining whether the network conditions necessary for activation of an aggregator facility are maintained for a given component area of ​​the aggregator facility. radio coverage; and determining whether sufficient network conditions to support activation of an aggregator facility are maintained for the component area.

In certain embodiments, the controlling entity can be configured to determine whether the network conditions necessary for activation of an aggregator facility are maintained by performing at least one of: determining whether the cell load exceeds a load threshold while the capacity of processing is below a minimum throughput threshold; determining whether the number of users in a cell region exceeds a threshold number of users while the throughput for a given application falls below a minimum throughput threshold; determine if a happiness metric is below a happiness threshold; and / or determining whether the use of control resources exceeds a control resource threshold.

In certain embodiments, sufficient network conditions for activation of an aggregator facility may depend on the level of at least one of the following parameters: the number of communication devices in the component area of ​​the radio coverage; the number of communication devices in the radio coverage component area that have aggregator functionality enabled; the signal-to-interference plus noise ratio, SINR; received signal path loss / received power, RSRP; available radio access technologies, operating frequency and / or carrier bands; the location information of communication devices; the mobility information of communication devices; and the predicted device power profile for the at least one communication device.

In certain embodiments, the at least one second communication device is one of: a user equipment (UE); a machine type communication device (MTC); a repeater; a relay unit; an access point; a wireless station; a small cell station; or a dedicated aggregator facility communication device.

In certain embodiments, determining whether a net benefit is expected as a result of activating the aggregator facility can be performed on a macro cell basis for at least one macro cell within the cellular telecommunications network.

Another aspect of the present description provides a computer program comprising arranged instructions, when executed, to implement a method according to the aspects described above.

Various respective aspects and features of the present disclosure are defined in the appended claims.

It is an objective of certain embodiments of the present disclosure to resolve, mitigate or obviate, at least in part, at least one of the problems and / or disadvantages associated with the prior art. Certain embodiments aim to provide at least one of the advantages described below.

Brief description of the drawings

Various embodiments of the present description will now be described with reference to the accompanying drawings, in which:

Figures 1A to 1C illustrate a radio access network where certain communication devices are dynamically assigned as aggregators within a single cell;

Figures 2A and 2B illustrate a further radio access network where certain communication devices are dynamically assigned as aggregators within a multi-cell network;

Figure 3 illustrates the functional elements of an aggregator controller suitable for enabling, controlling and disabling an aggregator layer in the network architecture of Figures 1A, 1B, 1C, 2A and 2B;

Figure 4 illustrates the behavior of nearby communication devices when the aggregator controller of Figure 3 enables an aggregator layer on a given aggregator;

Figure 5 illustrates the functional elements of a communication device suitable for use in the network architecture of Figures 1A, 1B, 1C, 2A and 2B; and Figures 6A and 6B show a flow chart illustrating exemplary operations of a method for determining activation of an aggregator facility (or "layer") in accordance with the present disclosure.

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Detailed description of preferred embodiments

The present description refers to radio resource management methods in a telecommunications network architecture that includes a radio access network (RAN), a core network (CN), and a packet data network (PDN). Communication devices, such as mobile terminals, user equipment (UE), and wireless access stations, establish wireless connections to the network via the RAN.

Figures 1A to 1C show a single cell 100 of the telecommunications network provided by a base transceiver station (ie macro eNB) 120 within the RAN. The telecommunications network architecture further comprises a network node, referred to as an aggregator controller (AC) 102, which communicates with the RAN and CN (illustrated here as a link between the AC 102 and the eNB 120 ) but that can be implemented independently of the component entities or the RAN or the CN.

AC 102 identifies at least one communication device 104 as a candidate for aggregator assignment. The AC 102 also instructs any given aggregator candidate 104 to activate (or deactivate) an aggregator mode, whereby it provides base station functionality for nearby (mobile) communication devices 110. The AC 102 also determines whether any aggregator candidate 104 is activated at all at any given time in a given region of the telecommunications network. In Figures 1A to 1C, the candidate aggregators 104 are illustrated as the UEs: this is merely an example of a suitable communication device 104, the candidate aggregators can equally be dedicated communication devices or even small cell base transceiver stations such as HeNBs or eNB femtocell.

The AC 102 is configured to interrogate one or more communication devices 104, where these devices are connected to the RAN (i.e., the eNB 120), to determine certain parameters associated with the device 104 and / or its connection to the RAN. (for example, SINR, received power to reference signal (RSRP), power to signal received code (RSCP), location information, battery life, etc.). The data associated with the parameters is processed in the AC 102 and, if it is determined that the parameters indicate that the or each communication device 104 is a candidate for assignment as an aggregator, the communication device 104 may be configured to implement a mode. aggregator, thereby providing base station functionality for nearby (mobile) communication devices 110.

Figures 1A to 1C also illustrate a scenario where the facility is contemplated to extend base station functionality to nearby (mobile) communication devices 110. As communication devices approach the furthest macro cell coverage interval in the cell (that is, the edge of the cell), they consume more network resources. By selecting certain communication devices to act as aggregators, these devices that are within good macro cell coverage but have the facility to extend base station functionality within an “aggregator cell” beyond the coverage of the macro cell layer, the network can deploy aggregators to address cell edge issues.

Certain communication devices 104 connected to the network are thus used as a type of small cell entity. The communication devices connected to the network assigned to perform this small cell-like functionality are called "aggregators" because, when there is more than one communication device 110 near a communication device 104 connected to the given network in aggregator mode , the data traffic from the nearby communication devices 110, for each of the nearby communication devices 110, is temporarily stored for transport (i.e., "Aggregates") using a backlink connection between aggregator 104 and the core network. By aggregating the data from one or more nearby communication devices 110, the aggregator can both (a) help extend network coverage to locations where (i) macro-layer coverage is otherwise either temporarily inadequate or permanently or (ii) macro layer coverage is adequate but devices within a certain coverage area (e.g. cell edge) consume too many resources as (b) transport data over the RAN more efficiently. One of the advantages of temporarily storing data from nearby communication devices 110 is that the backlink connection from aggregator 104 (which can be thought of as a single logical "tube") can be made less "bursty" by reducing the consumption of signal resources.

Aggregators are typically turned on and off dynamically depending on conditions that affect network performance. These performance conditions include both network conditions (such as interference, load, etc.) and other conditions that could affect system performance (such as the expected level of activity in the cell at a given time or date, the presence and / or number of candidate aggregators at suitable locations, the distribution of UEs at cell edge locations, and / or the level of resource consumption by the communication devices in the potential coverage area of ​​the respective candidate aggregators).

In certain cases, the existing macro layer coverage is used for the backlink and a different technology / band than the one used for the backlink is used as a radio interface to extend the coverage to communication devices (mobile) 110 close. The coverage extension, therefore, is supplied to nearby communication devices 110 by aggregators operating "out of band" with respect to macro layer operating frequencies.

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In one example, the macro layer operates using LTE carriers in frequency bands around 800 MHz or 1800 MHz, while the cell provided by the aggregator to nearby communication devices operates at 2600 MHz. In another example, the macro layer operates using LTE carriers in frequency bands around 2600MHz using FDD technology while the cell extension provided by the aggregator to nearby communication devices operates at 2600MHz in TDD technology. In addition, the reader will appreciate that additional out-of-band frequency bands may be available at frequencies for which no license is required, such as the 2.4GHz and 5GHz bands used by conventional WiFi technologies (i.e., compliant with the family of IEEE 802.11 standards).

It will be appreciated that in many cases the aggregators (and candidate aggregators) are themselves mobile. While in certain embodiments, it is a requirement that the aggregator be static when active, it is also contemplated that the aggregator can be moved to another site and activated at the new site, such communication devices are referred to as "nomads", unlike “fixed” devices. A specific example of a nomadic device arises when the candidate aggregator is installed in a motor vehicle, such as a commute car: the vehicle is driven from a home location (where it can be static) to an office location (where, after the journey is complete, the device can again remain motionless throughout the working day).

The AC 102 is a central logical entity (for example, a server), which may or may not be integrated within the elements of the 3GPP Radio Access Network. The AC 102 monitors conditions that affect network performance to help decide which UE 104 (or other communication devices connected to the network) will act as an aggregator.

Certain implementations of the AC 102 obtain information from all communication devices connected to the network in a given sector before determining which of these devices can act as aggregators by virtue of device status and current location. This determination is repeated for the respective sectors at time intervals: in certain cases, the intervals are equal in duration, while in others, the intervals are of variable duration and can be adapted to the known or predicted behavior of the communication devices using network.

The AC can repeatedly determine whether, under a set of basic criteria (i.e., performance conditions such as network conditions, current location and status of communication devices, etc.), any device in a given sector should go into service as an aggregator at all. The criteria may include a measure of the comparative benefit of introducing an aggregator facility versus not having an aggregator facility in a given industry.

The AC is capable of establishing, maintaining and deactivating communications with the candidate aggregators, that is, those UEs or other communication devices connected to the determined network have the capacity to act as aggregators. This capability (provided through an application layer carried over the macro layer user plane, for example) allows the AC to:

• obtain information from all UEs that can act as aggregators 104, this information may include performance factors such as location and its accuracy, supported RATs and related technologies (such as conventional WiFi technologies), supported operating frequency bands , battery characteristics, current battery status and consumption; and / or • provide commands to aggregators 104, such as: commands to configure an aggregator control layer using some specific algorithm depending on the performance conditions such as those obtained from the aggregators 104, to select the RAT / band to be used in such layer, to start transmission, to send commands of handover to aggregated UEs (i.e., nearby communication devices 110 served by aggregators 104), to stop transmission, and / or to send information to the aggregator control layer.

In certain implementations, the AC 102 may communicate with the LTE eNodeB or the 3G RNC in order to "move", through a handover to a specific RAT / frequency, a terminal (or other communication device) that is sets it to act as an aggregator 104. This movement may be a change in the serving cells: in such cases, the communication with the LTE or RNC eNodeB is a request for a handover of the aggregator 104 from a current cell to a neighboring cell: the communication with the eNodeB or RNC It is necessary then, since the handovers are under the control of the LTE eNode (for 3G, the control is done by the RNC). The move could also be a forced reselection: in which case, communication with the LTE eNodeB would be unnecessary.

In certain implementations, the AC 102 may establish additional direct communication with "normal" UE 110s (ie, those communication devices that are not currently assigned to act as aggregators). This direct communication can be via a pre-installed application, for example configured to collect additional performance information, such as signal strength / quality.

ES 2 838 677 T3 received in cell 100 where normal UE 110s are seated / connected, and / or data on the intensity / quality of signals received in other RAT / bands, and / or location information.

In certain implementations, aggregation-enabled communication devices 104 (ie, aggregators or candidate devices) are also relay nodes. Such devices can transfer data for one group of communication devices connected to the network as a conventional relay node, while serving another group of communication devices connected to the network as an aggregator.

The aggregator 104 is different from a typical relay node in a number of respects. First, the relay nodes are linked to a particular donor cell. They are assumed to be static and fully under the control of the network operator through the eNB provided by the donor cell. Furthermore, the relay nodes are normally operated using radio resources allocated to them by the donor cell and thus are integrated into the macro cell scheduling. In logical terms, a connection from a communication device to the core network through a relay node is the same logical connection as that between the communication device and the core network through the donor eNB: a resource that would be allocated within The macro layer for the direct connection from the communication device to the eNodeB is instead assigned to the indirect connection through the relay unit.

The macro layer (ie, provided by eNB 120) and aggregator 104 provide separate logical connections between the Core Network and communication device 110, with aggregator 104 being "configurable" to provide this connection. While the relay node provides an alternate physical route provided the communication device sits in the relay cell rather than the donor cell, AC 102 ensures that the network can control whether a candidate (or group of candidates) given for the aggregator is enabled (that is, it enters service as an aggregator) and thus determines the conditions under which the communication device switches between a connection established by the RAN and a connection established by the aggregator (when exemplified).

Figures 2A and 2B illustrate a further radio access network where certain communication devices are dynamically assigned as aggregators within a multi-cell network. This scenario demonstrates that the aggregator is not, however, merely a "temporary" base transceiver station. As the aggregator is activated and deactivated for this (that is, opportunistically) based on the need for the RAN as a whole, it is contemplated that certain communication devices 204 seated in neighboring cells 280 could be assigned an aggregator state.

Such aggregators 204 may be arranged to provide more efficient base station functionality to communication devices in cell 200 that currently serve a conventional communication device 210. While that aggregator 204 would normally be out of range of serving cell 200, it can nevertheless be activated through AC 202.

Since the AC 202 need not be specifically associated with a given cell 200, but rather with a network that may include a plurality of cells (200, 280), the AC 202 is adapted to view the network holistically. By activating aggregator facilities 204 that sit outside the coverage (macro layer) of a cell 200 but still serve communication devices 210 within that cell 200, the AC 202 can still provide a general benefit to the network.

Figure 3 illustrates the functional elements of an aggregator controller 300 suitable for enabling, controlling, and disabling an aggregator layer in the network architecture of Figures 1A, 1B, 1C, 2A, or 2B. These functional elements can be implemented as software routines and / or as dedicated hardware units, these elements being substantially interchangeable.

The functional elements include a communication module 320 to obtain information from potential aggregators by establishing communication through an application layer with these devices. The information obtained contributes to the factors that affect the performance of the network on which the establishment of a connection between aggregators and nearby communication devices depends, and may include: a current location (for example, location information derived from systems of global or regional satellite positioning, such as the Global Positioning Satellite, GPS); historical information (covering, for example, the last two weeks) of the location of the candidate aggregator; current level of physical mobility (that is, whether or not you move); a measure of LTE radio coverage in the macro layer; an indicator of battery level, current consumption, expected remaining battery, etc .; information concerning the neighboring cells of the aggregator, regarding the connection between the aggregator and the macro RAN layer; and a measure of the expected (or otherwise) improvements, after turning on an aggregator layer in a specific region of the radio network, the improvements that are measured in terms of latency (i.e. data timeout) , for instance. This information can be made available at the application layer through an aggregator client application running on the respective candidate aggregator devices.

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One reason for obtaining such information relates to the nature of the devices that are candidates. It is likely that many of the candidate aggregators are in fact "nomadic", shifting (ie commuting) between two or more static locations over a period of hours or days. Thus, for many candidate devices, the characteristics of the network will change as they move within the network: a communication device that is a suitable candidate aggregator at a given location, X, and at a given time, T, may not be suitable elsewhere, X + x, at a later time, T + t: specifically if the location is close enough to extend an aggregator cell to the cell border (macro layer) at T, but outside the range of the cell border at T + t. Thus, controller 300 needs to obtain this information to inform decisions as to whether the communication device is (currently) a candidate aggregator and whether, if it is a candidate aggregator, it should be activated / deactivated as an aggregator.

Optionally, communication module 320 can be configured to obtain additional information from communication devices other than aggregators; this additional information that is analogous to the information obtained from the candidate aggregators and that contributes in a similar way to the factors that affect the performance of the network on which the establishment of a connection between aggregators and nearby communication devices depends. A specific non-aggregator client application can be installed on some or all of the communication devices within a network to provide this additional information.

The communication module 320 can also be configured to obtain macro layer information (that is, data concerning network conditions) from the macro layer concerning the current level of resource consumption of programmers, coverage maps and (if available) real-time traffic maps.

The functional elements include a selection module 330 to select (and communicate with) the aggregators to initiate transmission of an aggregator cell and to determine which of the supported frequency bands / technology the selected aggregators are to use in operation.

A monitoring module 340 is also provided to evaluate performance conditions (such as network conditions and other conditions affecting performance) to determine which of the currently selected aggregators will continue its transmission.

In cases where a change in the aggregator is indicated by the monitoring module 340, the selection module 330 can be further configured to select (and communicate with) those aggregators that should stop their transmission (and therefore allow being in service as an aggregator).

When an aggregator layer is enabled in a given sector or cell of a radio network, the aggregator controller first instructs one or more communication devices (preselected to act as aggregators) to begin radiating coverage (i.e. , to implement an aggregator "cell").

In Figure 4, communication device activity near an active aggregator is illustrated. Once a given aggregator begins to radiate coverage to its own cell 405, the behavior of nearby communication devices is adapted accordingly.

Nearby communication devices (i.e. terminals, such as UEs) that are in idle mode, will automatically settle into the newly established aggregator cell 420 (by virtue of the cell's conventional idle mode reselection with the intensity of stronger signal coupled with prioritization of the LTE layers broadcast by the LTE eNodeB). If the nearby idle device thereafter enters an active mode 430, transmission is initiated (or not initiated) over aggregator cell 440. When there is an existing connection in progress through the macro-layer of the RAN (that is, the nearby communication device is determined to be active in the macro-layer) 410, the RAN can optionally, upon request of the aggregator controller, move (ie, transfer) the current communication from the respective nearby device to aggregator cell 415. If such a request is made, transmission is initiated (or continued) on aggregator cell 440.

Figure 5 illustrates the functional elements of a communication device 500 suitable for use as an aggregator in the network architecture of Figure 1A, 1B, 1C, 2A, or 2B.

The communication device 500 includes a memory 510, location unit 520, a processor 540, input / output devices 550, and a network interface unit 560 having a transceiver module 565. Data is transferred between the various components through of a bus 545. To operate as an aggregator, the network interface unit 560, through its transceiver module 545, must be capable of establishing two separate network interfaces: a backhaul link interface and a coverage extension interface. In certain implementations, the transceiver module operates in at least two sets of frequency bands: a set of bands that correspond to the macro layer RAT and an additional set of "out-of-band" frequencies not used by the RAT. In some cases, communications on the “out-of-band” frequency set use a different RAT than the macro layer.

In certain implementations, the backhaul link and the coverage extension interface could use the same work frequency / RAT as a conventional relay node in order to facilitate the deployment of multi-hop scenarios, in which chains of Radio Access Network entities. By

For example, a first aggregator may appear to other communication devices as a Donor eNodeB and a second aggregator may appear to the first aggregator as a conventional UE while providing its own cell to nearby communication devices appearing to them as a conventional Relay Node.

Location unit 520 may include a global positioning satellite (GPS) unit or the like to provide location information for communication unit 500, as well as cell synchronization if other methods are not available.

Although not shown, the communication device 500 may be powered from a battery, such as a rechargeable lithium ion battery, conventional in the field of portable cellular communication devices, such as smart phones.

Even if there are conditions that suggest that it would be possible to deploy one or more aggregation layers in a cellular communication network, there must be good reason for deciding to configure an aggregator layer: in essence, there needs to be some tangible expected benefit of doing so. instead of persisting with the normal macro layer operation.

Figures 6A and 6B show a flow chart of an exemplary method in accordance with aspects of the present disclosure.

In step S610, the controller obtains values ​​for one or more cell or user related metrics, referred to hereinafter as "cell metrics", thereby testing the performance of the macro layer. Cell metrics can include, for example, measurements of: cell load (for example, resource block usage (RB)), cell throughput, number of active communication devices located in predefined parts of the cell coverage area, a “happiness” value for users (measured latency in data transfer, uplink timeout or a value obtained by inference from user feedback on social networking services, for example); and / or the use of control resources (eg, the use of PDCCH).

Cell metrics provide a macro layer performance measure that is used in determining whether conditions in a component area of ​​radio coverage offered by a cellular communication network support the activation of an aggregator facility. In this case, a given radio coverage component area can be selected from: a macro cell coverage area for at least one macro cell within the cellular telecommunications network; a coverage area for at least one sector within the macro layer of the cellular telecommunications network; and the coverage area of ​​the entire cellular telecommunications network.

In Figure 6A, for example, this determination involves two distinct steps: step S612, which deals with certain maintained conditions that would make activation of an aggregator facility desirable (even necessary), and step S614, which deals with additional conditions. which would determine whether such an installation would be feasible. In alternative approaches, the conditions supporting the activation of an aggregator facility can be performed in other ways, in particular steps S612 and S614 can be performed in parallel with each other or in "reverse" order; furthermore, all conditions can be evaluated in a single procedure based on cell metrics.

In step S612, the controller determines whether the cell metrics meet the target threshold values. This operation may include: determining if the cell load (ie use of RB) exceeds a load threshold while the flow rate is below a minimum flow threshold; determine if the number of users in a cell region (such as the edge of the cell) exceeds a threshold number of users, while the throughput per application (App) falls below a minimum throughput threshold of the App; determine if a happiness metric (whether aggregated for a number of users or a group of users or not) is below a happiness threshold; and / or determining whether the use of control resources (such as a PDCCH) exceeds a control resource threshold.

If the cell metrics meet the target threshold conditions, the controller concludes that the conditions necessary for the aggregator layer deployment are maintained and moves to step S614.

In step S614, the controller determines whether certain conditions sufficient for deployment of the aggregator layer are maintained. The controller thus determined whether effective aggregator layer deployment will be possible. Step S614 may include determining:

whether there are aggregator-enabled communication devices (i.e. candidate aggregator devices) in the cell and whether these communication devices have certain characteristics in terms of mobility (e.g. they are, have been for an amount of time and / or are expected that are "static");

if there are communication devices (aggregator enabled or not) in one or more macro cells with certain characteristics in terms of mobility (eg, they are, have been for an amount of time and / or are expected to be "static");

ES 2 838 677 T3 if the controller has access to the data concerning the loss of path to the macro cell and / or between communication devices (for example, UE / terminals) and / or location information of the aggregators and / or the other communication devices;

if there are communication devices in coverage of potential aggregators;

if there is a match between the capabilities (technology / band supported) between aggregators and nearby communication devices;

if at least some of the aggregators have sufficient battery life to maintain aggregator functionality for a predetermined period of time;

if low interference conditions are maintained; and / or if necessary spectrum and technology resources are available for use in aggregator layer deployment.

If the controller concludes that sufficient conditions are maintained for the aggregator layer deployment, the controller then performs operation S616. In certain alternative approaches, the controller performs operation S616 before or in parallel with the operations at S612 and / or S614.

In step S616, the controller makes a preliminary determination as to whether a benefit to the network would be expected if the network were to deploy the aggregator layer. This preliminary determination considers a limited number of properties of the cell metrics obtained in operation S610 and is thus based on a subset of the information necessary for the aggregator layer deployment: for example, a benefit would be expected at this stage because there were multiple static users on the edge of the cell under the potential coverage of some static aggregators.

If it is determined that either the necessary conditions (in step S612) or the sufficient conditions (in step S614) are not present, the controller waits for a predetermined period of time (by setting a timer, for example) and then obtains a additional set of cell metrics (in step S610). Likewise, if it is determined that no benefits are expected from the aggregator layer deployment (in step S616), the controller will return to step S610 and obtain an additional set of cell metrics.

If, however, in step S616, the controller makes a preliminary determination that there would be an expected benefit, in principle, to the network if the aggregator layer were to be deployed, the controller initiates a more detailed phase of operation (illustrated in Figure 6B) collecting additional performance information, operation S620 (in addition to the cell metrics obtained in operation S610).

During the collection of additional performance information, operation S620, the controller obtains a list of aggregator-enabled communication devices (i.e., candidate aggregators) currently seated within a given macro cell, using received information updates, at time-spaced intervals. , of the aggregators. In addition to the list of candidate aggregators, the additional performance information may include some or all of the following information obtained from the respective aggregators:

• location (of the update aggregator). This location information can be obtained by the aggregator by inference from the RSRP and / or using a GPS unit.

• path loss / SINR (measured in update aggregator). This can be with respect to the current macro cell or to a set of macro cells.

• level of mobility (static or not) measured by the aggregator itself • information about the location and / or path loss of all UEs or other communication devices connected to the network that are static (optionally, this can be filter to relate only to UEs that are static and that are also expected to remain static analyzing and using geolocated historical information of the UE) and that are settled / or are / have been connected there.

The controller processes some or all of this performance information to evaluate the relative distance and path loss / SINR (or similar quality) between the candidate aggregators and the user devices in the cell.

In certain embodiments, the controller selects aggregators from aggregator-enabled communication devices according to a single aggregator selection algorithm. In other embodiments, there may be a plurality of aggregator selection routines (ie algorithms) available and it is first necessary to determine which routine to adopt. When required, the operation of determining which routine to use can be any conventional selection operation.

ES 2 838 677 T3

Figure 6B illustrates an embodiment in which a plurality of aggregator selection routines are available. In this case, the respective available aggregator selection routines can each be tailored to the respective different performance conditions. In step S622, an algorithm corresponding to one of these routines is determined depending on the availability of specific additional performance information, such as aggregator location information or path loss measurement data. In cases where only a single aggregator selection algorithm is available, determining which algorithm to use is trivial and step S622 can be omitted.

Once it is determined which routine (that is, algorithm) is appropriate to the additional performance information available, this algorithm determines, if any, which aggregator-enabled devices should be activated for aggregator functionality and defines the threads using the which profit (i.e. achievable profit) will be calculated from the aggregator layer deployment. The algorithm thus serves to select aggregators from among candidate aggregators for aggregator layer deployment. The operation of this algorithm is illustrated as operation S624 in Figure 6B.

At step S624 (whether this is the only aggregator selection routine available or a routine that is determined to be suitable for the additional performance information available at step S622), the controller makes a selection from among the monitoring devices. communication enabled with aggregator, this selection being a selection of one or more aggregators based on either the individual characteristics of the respective selected aggregators or the collective characteristics when the selected aggregators are considered as a selected group from among aggregator-enabled communication devices.

In certain embodiments, aggregator selection includes selection as a group of some or all different possible groups or subsets of aggregator-enabled communication devices, each group being referred to as an "evaluation group." An expected gain is then calculated for each evaluation group.

In other embodiments, the aggregator selection is the selection of individual devices (ie, subsets of aggregator-enabled communication devices that each have a single member). In this case, the expected profit is calculated for each individual candidate aggregator.

The expected (achievable) gain results from an evaluation of the expected improvement in a given cell metric: this cell metric can be the, or one of, the cell metrics obtained in step S610. For example, the expected gain may be the result of a comparison between a) the value of that given cell metric when the or each aggregator is selected and b) the currently experienced (that is, measured) value of that cell metric.

In certain cases, the expected gain can be expressed as the difference between the value of a given cell metric predicted for a given evaluation group (evaluated before actually activating that group for aggregator functionality) and the current value of the metric of given cell. When aggregator-enabled communication devices are not activated, the current value of the cell metric is the measured value of the cell metric for the cellular communication network where no aggregator functionality is activated. Otherwise, the current value of the cell metric is the measured value of the cell metric for the network in which a current group of aggregator-enabled communication devices are activated for aggregator functionality, such current group does not need be the evaluation group. The prediction of the cell metric may be a function of the additional performance information collected in operation S620.

When determining the expected gain for individual candidate evaluation groups or aggregators, the aggregator selection algorithm then evaluates the respective expected gains for some or all of the different possible aggregators or aggregators groups, the aggregator or aggregator group selected may be the individual or group that provides the highest expected profit. Alternatively, the selected aggregator or group of aggregators may be a group from a subset of groups that have gains that exceed a threshold gain, taking into account other practical constraints such as keeping aggregators that are already active, unless there is one. good reason to stop them (for example, battery level dropping below a level that can support continued operation or detected motion of the active aggregator).

In step S626, the controller makes a full determination of whether a benefit to the network would be expected if the network were to deploy the aggregator layer by modeling network performance for a network with the selected aggregator or aggregator group enabled and comparing that performance with the currently measured network performance information (as collected in step S620).

In the case of aggregator selection using evaluation groups, the complete determination of the benefit to the network involves comparing the expected profit from using the selected evaluation group of aggregators with data representative of current network performance.

In a specific example where one of the selected subsets of aggregators is not currently active, sufficient benefit would be confirmed from the first activation of that selected subset where

ES 2 838 677 T3 the measured value of a given cell metric (assuming that the given cell metric is the one used in the algorithm in step S624) is significantly higher than the cell metric measured before activation.

In another example when the aggregator layer is on (that is, at least a subset of aggregator-enabled communication devices are turned on for aggregator functionality), sufficient profit is confirmed when the gain is higher than one of a metric reference average (for example, historical data) or a cell metric measured in the last N previous iterations, where N is an integer greater than 1.

If the determination in step S626 is that a net benefit is indeed provided by deploying the selected device or group of devices (i.e., subset) as the aggregators, the controller activates an aggregator server (step S628) to support the aggregator layer. aggregator and instructs each of the selected communication devices to activate (or keep active) their respective aggregator functionalities (for example, running a routine in an aggregator client application). These aggregator functionalities include functionalities consistent with the operation as a MiFi architecture access point (offering the WiFi protocol and / or VLC connectivity to nearby communication devices) and / or as a small cell (offering connectivity using a standard of cellular telecommunications).

While not illustrated in Figure 6B, the controller can conveniently launch a RAT selection routine to determine which carrier / RAT / band bandwidth will be used by each aggregator (selected), the carrier / RAT bandwidth / band will be chosen from one or more permutations of RAT, band and available carrier bandwidth, available for the implementation of an aggregator layer in a specific cell. For example, the RAT select routine may determine that since LTE's FDD2.6 is not used in the current and / or neighboring macro cell, it can be used by all selected aggregators within the range of those cells.

As discussed in relation to Figure 4, nearby communication devices may transfer some or all of their data traffic to the selected aggregator (s) differently depending on whether they are in the "idle" state. or "connected."

In the first case, the transfer of inactive devices can be facilitated by the controller modifying the neighbor cell list (NCL), which is provided to the devices in inactive mode, with the parameters of the selected active aggregators.

In the latter case, the controller can determine whether to request a handover for a device in the connected state when information, just as the radio measurements of the communication devices in the macro cell compare unfavorably with the radio measurements of the communication devices used by the selected aggregators (always provided that such information is available and could be accessed by the relevant RRM function of the eNodeB / RNC in the macro cell). Examples of communication devices for which a handover could be requested include those devices: a) that are in the coverage area of ​​a specific aggregator (s) and b) that have a channel quality indicator (CQI) and / or RSRP in relation to the macro cell which is worse than that of the aggregators.

Although not illustrated in Figure 4, the aggregator may alternatively (or additionally) offer WiFi protocol connectivity to nearby communication devices (thereby operating as a MiFi architecture access point). In such cases, the handover over aggregation functionality can be accomplished by informing the respective nearby communication devices whose aggregators offer an access point in the cell and ordering those communication devices near the identified access points to enable Wi transmission. -Fi.

Optionally, the controller can then seek to optimize the aggregator layer, step S630.

Driver optimization can include at least one of the following:

• check, once a given nearby communication device is connected to an aggregator, whether that device has a worse CQl / SINR / RSRP with respect to the macro cell than with respect to the aggregator, and in such case it will be (or may be ) handed over to the Macrolayer (for example, by issuing a handover command or releasing the aggregation connection with redirection). Conveniently, the selection parameters for this device would be changed for an amount of time to avoid unwanted ping-pong effects (ie, hysteresis);

• check the performance at the aggregator layer versus the performance that would be expected if a given communication device were to remain in the macro layer, depending on what information can be made available to the controller and / or aggregator. Examples of performance information that can be verified include user happiness metrics measures such as: latency (i.e. round trip time (RTT) for packets transmitted and received or uplink timeout Examples of performance information that can be verified may also include:

ES 2 838 677 T3 historical data (such as the flow rate for specific applications) obtained in the macro layer at a similar or the same location and under the same or similar RSRP / CQI conditions;

• check the level of interference and / or availability of resources for the spectrum / technology used in the aggregator layer and take actions to improve these parameters (for example, create groups of use of spectrum / technology, reduce the use of those resources in the macro layer); and • optimize the selection of aggregators taking into account mobility. Aggregators themselves may be required to take certain actions when added users (that is, communication devices using the aggregation facility of a selected aggregator) initiate mobility. Likewise, when the aggregators themselves become mobile, the controller can act to alter the performance of the aggregator later, for example by instructing the new mobile aggregator to turn off aggregation functionality.

Checking the performance at the aggregator layer using RTT may involve comparing RTT for the same packet using the macro cell and the current aggregation layer service, respectively. Using the uplink timeout to check performance may involve comparing this time before and after optimization.

Testing performance at the aggregator layer using historical data may involve comparing historical data with actual data obtained through the aggregator. It is also possible to run periodic speed tests just to check the current quality.

Whether or not optimized as described, the controller iterates again through operations S622, S624, and S626, selecting one or more aggregators that may be identical to the aggregator (s) selected in previous iterations. or they may represent a group that has a different constitution of aggregator-enabled communication devices.

Periodically, cell metrics are checked, step S632, and this information is used in further iterations of steps S622, S624, and S626. The cell metrics checked here can be the same as those obtained in operation S610: they can also be different from those cell metrics.

If the determination in step S626 is that a net benefit is not actually provided by deploying the selected devices (or group of devices) as aggregators, the controller stops using the aggregator layer operation S640. This may involve instructing all aggregator-enabled communication devices in the cell to deactivate their aggregator functionality and deactivate the aggregator layer server in the controller.

After a second predetermined time (normally longer than the typical period of the iteration of operations S622, S624 and S626), the controller restarts the first phase of determining the preliminary benefit of the deployment of the aggregator layer in operation S610 .

In a further embodiment of the present description, more than one aggregation layer is activated within the network. In certain cases, the respective aggregation layers are turned on and off in the corresponding sectors or groups of sectors of the cellular network. In certain cases, the aggregation layers are established within a sector or cell that extends the coverage of that sector or cell to encompass communication devices served by neighboring sectors or cells: in this way, the benefit to the network of the deployment of any A given aggregation layer can be calculated for a region of the radio coverage of the cellular network that includes more than one sector and / or cell.

Certain embodiments of the present disclosure relate to the dynamic activation of one or more communication devices to provide an aggregation layer. Each of the one or more communication devices appears in the macro layer as a UE; while for other communication devices, each appears as a kind of small cell base transceiver station. The dynamic activation is due in part to the determination of whether a benefit could be expected from such dual UE / small cell activation: that could arise if the macro layer does not provide a quality of service prerequisite to the other communication devices. Dynamic activation also requires finer-tuned determination dependent on selecting a set of devices capable of dual UE / small cell or UE / MiFi functionality for activation and determining whether the network would benefit from the activation of that particular group. Only when it is determined that the network benefits based on this detailed determination will the selected communication devices be activated as hybrid UE / small cells (or UE / MiFi devices).

It will be appreciated that, although various aspects and embodiments of the present invention have been described thus far, the scope of the present invention is not limited to the particular arrangements set forth herein and is instead extended to encompass all arrangements, and modifications and alterations thereto, which fall within the scope of the appended claims.

For example, while the embodiments described in the preceding description refer to LTE, it should be noted that the described aggregator architecture can be equally deployed in telecommunications networks.

ES 2 838 677 T3 based on other cellular telecommunications architectures, eg 2G, 3G, Advanced LTE (3GPP Version 10 forward), future architectures (eg 5G), as well as WD-CDMA and WiMAX. The aggregator architecture is agnostic for the specific type of RAN used. In other words, the aggregator / controlling entity controller is adapted to work with any RAN and / or combinations of RANs. This is, for example, one of the reasons why, in certain embodiments, the aggregator / controlling entity controller is independent of the RAN. Similar remarks apply to the communication device to provide an aggregator facility.

Furthermore, it will be apparent to the reader that the term radio access technology (RAT) can be extended to include related technologies, such as conventional WiFi technologies (i.e., conforming to the IEEE 802.11 family of standards), where the context requires or permits. this.

Furthermore, while the above description describes the aggregation layer as providing a bridge to the cellular network for communication devices that are at the edges of cells, the skilled reader will appreciate that "black spots" of dynamic coverage can arise in other parts within radio coverage regions (for example, due to equipment malfunction, unusual usage patterns, and / or characteristics of the natural or built environment).

It will also be well understood by those skilled in the art that, while the described embodiments implement certain functionality by means of software, that functionality could likewise be implemented solely in hardware (for example, by means of one or more ASICs (Application Integrated Circuits). specific)) or actually by a mixture of hardware and software. Therefore, the scope of the present invention should not be construed as being limited only to being implemented in software.