RU2575702C2 - Methods and network nodes for configuring almost blank subframe transmission patterns and corresponding measurement patterns for reducing intercell interference in heterogeneous cellular radio communication system - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: invention relates to communication engineering. A method and a network node for enabling configuration of at least two patterns for a cell (C0) are provided. The patterns are transmission patterns or measurement patterns. The network node obtains at least two patterns. Each of the at least two patterns is associated with information about a respective restricted area (A1, A2) such that each pattern is used when user equipment served by the cell (C0) is located in the respective restricted area. Each respective restricted area (A1, A2) is smaller than an entire area of the cell (C0).

EFFECT: improved efficiency of the radio communication system.

21 cl, 15 dwg

Description

FIELD OF THE INVENTION

The embodiments presented herein relate to a method executed in a network node and a network node for enabling configuration of at least two patterns for a cell. In addition, embodiments presented herein relate to a method executed in a user device and a user device for configuring measurements.

BACKGROUND

Interest in deploying low-power nodes such as pico base stations, home radio base stations (home eNBs), repeaters, remote radio headend stations, etc., has continuously increased in the network over the past few years. When a network uses low-power nodes in addition to standard base stations, it is usually referred to as a heterogeneous network. Standard base stations are often referred to as the macro level, and low-power nodes are referred to as the peak level. The goal of using low-power nodes is to increase macro level performance in terms of network coverage, capabilities and operational experience of individual users.

At the same time, along with the growing interest in low-power nodes, it became clear that there is a need for improved interference management techniques to take measures in relation to the problems associated with interference caused, for example, by significant fluctuations in the transmission power between different cells. Cell linking techniques for more homogeneous networks are also needed.

In the Third Generation Partnership Project (3GPP), heterogeneous network deployments were defined as deployments in which low-power nodes with varying transmit powers are placed across the entire cell topology, assuming non-uniform traffic distribution. Such deployments, for example, are effective for building capacity in specific areas. These areas may include so-called traffic “hot spots”, that is, small geographic areas with increased user density and / or increased traffic intensity. Installing low-power nodes such as pico nodes in these areas can improve performance. Heterogeneous deployments can also be considered an option for compacting or concentrating networks to take action on traffic and environmental needs. However, heterogeneous deployments also introduce the difficulties for which the network must be prepared in order to ensure efficient network operation and exceptional operational experience. Therefore, various interference management techniques or interference management procedures have been proposed.

One example of such an interference management procedure relates to interference management for heterogeneous deployments. In order to provide reliable transmissions with a high bit rate, as well as reliable operation of the control channel, maintaining good signal quality is necessary for wireless networks. The signal quality is determined by the level of the received signal and its ratio to the sum of the interference and noise received by the receiver. A good network plan, for example, good cell planning, is a prerequisite for the successful functioning of the network, but cell planning is static. To use the radio resource more efficiently, the network plan should be supplemented with mechanisms for semi-static and dynamic radio resource management. These mechanisms are aimed at simplifying interference management and implementing more advanced technologies and algorithms associated with antennas.

One of the ways to deal with interference is to use more advanced transceiver technologies, for example, by implementing interference cancellation mechanisms in terminals or user devices (UEs). Another option, which may be complementary to the previous one, is the creation of effective interference coordination algorithms, such as inter-cell interference coordination (ICIC) and network transmission schemes.

Inter-cell interference coordination methods (ICICs) for coordinating inter-cell data transmissions were defined in revision 8 of the Long-Term Communication Network (LTE) standard. In LTE edition 8, ICIC information exchange between cells in LTE is performed via the X2 interface using the X2 application protocol (X2-AP protocol). The X2 interface and X2-AP are known from 3GPP terminology. Based on this information, the network can dynamically coordinate data transmissions in different cells in the time-frequency domain, as well as using power control, so that the negative impact of mutual interference between cells is minimized. With this coordination, base stations can optimize their resource allocation by cells both autonomously and through another network node that provides centralized or semi-centralized coordination of resources in the network. In current 3GPP specifications, such coordination is usually transparent to user devices.

Two examples of interference coordination with respect to data channels are illustrated in FIG. 1a and FIG. 1b. In FIG. 1a-1e, subcarriers, i.e., different frequencies, are arranged vertically along the vertical axis and time is reflected along the horizontal direction. Illustrative data channels are designated D1, D2, D3, and D4. In the example of FIG. 1a, data transmissions, such as D1, D2, D3 and D4, are separated in two cells in frequency, that is, the data areas D1, D4 do not overlap in the vertical direction without data. Two cells, such as pico and macro, belong to different levels, that is, to macro and pico levels. In the example of FIG. 1b, in contrast, low interference subframes are created at some points in time, such as a central subframe of the three subframes shown for macro, for data transmissions in pico cells by suppressing macro cell transmissions at these times. This can, for example, increase the performance of user devices that might otherwise be exposed to strong interference from macro cells. For example, this applies to user devices that are located close to macrocells or to macro base radio stations. Similar coordination mechanisms are possible even under current technical conditions.

Unlike data communications, current specifications limit ICIC's capabilities with respect to control channels. For example, the mechanisms illustrated in FIG. 1a-1b are not possible for control channels and are not possible for reference signals measured for mobility.

FIG. 1c-1e illustrate three approaches (1), (2), (3) advanced ICIC in order to deal with interference in the control channels.

(1) FIG. 1c illustrates the use of low-interference subframes in time.

In FIG. 1c, vertical bars represent reduced interference with control channels in the control area.

(2) FIG. 1d illustrates the use of time shifts. It should be noted that (2) has some limitations for time division duplex (TDD) communication and is not possible with synchronous network deployments. In addition, (2) is not effective at high information loads. From the point of view of legacy terminals, cell-specific reference signals (CRS) must be transmitted in all subframes, so that there will still be inter-cell interference from the CRS.

(3) FIG. 1e illustrates the use of an in-band control channel in combination with frequency reuse. In FIG. 1e, the arrays reflect reduced interference with improved control channels in the data area.

(1) and (3) require changes to standardization, while (2) is possible with the existing standard.

Interference coordination techniques, as illustrated in FIG. 1a-1e, reduce interference from a strong source of interference, such as macro cells during transmissions of other cells, such as pico cells. When implementing this, these methods assume that second cells, such as pico cells, are notified of the time-frequency resources with low interference conditions and, thus, can prioritize transmission planning in those subframes for users that could potentially be heavily affected by interference caused by strong sources of interference.

As noted above, the ability to effectively reduce inter-cell interference to and from control channels is limited by the existing standard. However, even less flexibility exists regarding interference to / from physical signals, which usually have a predetermined static resource allocation in the time-frequency domain. Some well-known noise reduction techniques are described below.

In signal suppression methods, a channel is measured and used to reconstruct a signal from a limited number of the strongest sources of interference. This method has an impact on receiver implementation and its complexity. In addition, in practice, channel estimation imposes a limit on how much signal energy can be subtracted.

In the time-shift methods of the symbol level, there is no effect on the standard, but this is not relevant for TDD networks or networks providing the MBMS service. This method is applicable when the macro base station and the home base station are time synchronized. This approach uses a time shift from the home base station relative to the downlink frame synchronization of the macro base station and uses power reduction or muting, by the home base station and / or macro base station, by parts of the character (s) that overlap the macro control area or home base station.

An additional method contributes to the complete jamming of the signal in the subframe. In this method, CRS are not transmitted at all in some subframes due to energy efficiency. This method was previously proposed in 3GPP. The method is not backward compatible with user devices corresponding to version 8 and / or 9, which require the transmission of CRS at least via antenna port 0.

With the very limited set of interference mitigation options outlined above, there is a great need for simple but effective new methods to solve the CRS interference problem. A similar problem exists, for example, for synchronization and broadcast channels, where time offsets can be used to solve the problem.

The need for improved ICIC techniques is especially critical when the assignment rule for cells deviates from an approach based on the received reference signal power (RSRP), for example, an approach based on path loss or path acquisition. This is sometimes referred to as cell range extension when adopted for cells with transmission power lower than neighboring cells. The idea of expanding a cell range is illustrated in FIG. 2, where the cell range is expanded using a delta parameter, also known as offset or deviation when selecting a cell. A cell range extension approach is also known as an offset cell selection.

As discussed above, various interference coordination techniques, also referred to as enhanced ICICs, have been considered in the context of heterogeneous network deployments.

Now, returning to the X2 interface, the information to be signaled between radio base stations and from radio base stations such as eNodeB to a user equipment (UE) is described. It was suggested that the alarm should contain the following:

- one bitmap template for indicating an almost empty subframe (ABS) pattern of a macro cell to a pico cell,

a second bitmap template for indicating a subgroup of subframes designated by the first bitmap, which are recommended for the receiving node for configuring limited measurements of radio link monitoring (RLM) and radio resource management (RRM), and

- pattern length and frequency: frequency division duplex (FDD) -40 ms, TDD-20 ms for 1 ~ 5 downlink and / or uplink (DL / UL) configuration, 70 ms - for 0 DL / UL configuration, 60 ms - for 6 DL / UL configuration.

It has also been proposed that the required Radio Resource Control (RRC) signaling comprises RRC signaling for resource-specific RLM / RRM measurements and channel status information (CSI) measurements, where resources that can be used for measurements are indicated by patterns, such as an ABS pattern or template for RLM / RRM. The definition of ABS subframes is described below. For an ABS subframe, user devices may assume the following:

- all ABS subframes transmit CRS;

- if the primary synchronization signal (PSS), the secondary synchronization signal (SSS), the physical broadcast channel (PBCH), the system information block 1 (SIB1), the paging and / or positioning reference signals (PRS) coincide with the ABS, they are transmitted to the ABS (with an associated PDCCH when SIB1 / paging is transmitted);

- the need to support previous versions;

- transmission of CSI reference signals (CSI-RS) to the ABS is not yet defined;

- no other signals are transmitted to the ABS;

- if the ABS matches the subframe of the multicast / broadcast single-frequency network (MBSFN), not transmitting any signal in the data area, CRS is not present in the data area;

- the MBSFN subframe transmitting the signal in the data area will not be configured as ABS.

In accordance with the current state of the art, a measurement pattern for each cell should be defined. The measurement pattern is determined by the bitmap, which is communicated to the user device, and should not be the same as the transfer pattern.

In a scenario where loading among cells varies significantly, it is expected that different ABS patterns are configured in different cells. When defining a measurement pattern, various ABS patterns will need to be taken into account. Thus, only a small set of resources can be available for measurements. As a result, the measurement quality may decrease, and the measurement time may increase.

In addition, in accordance with the current state of the art, a transmission pattern, or ABS pattern, may be signaled to an adjacent radio node. The transfer pattern is determined by another bitmap.

With reference to the aforementioned scenario, the ABS template imposes a limitation on network performance, in particular within the scope of which measurement template can be used.

3GPP project: R2-106449, ALCATEL-LUCENT, entitled “Message Support for Nearly Empty Subframe Templates”, available November 9, 2010 (2010-11-09), XP050487151, RAN WG2, Jacksonville, USA, signaling for improvement is being disclosed coordination of inter-cell interference. For example, X2 and RRC signaling are described. In one example, with a UE-specific signaling, the pico eNB may indicate a suitable ABS pattern for the UE based on its location (based on the strongest interference source). As an alternative, it is also possible to provide the UE with two sets of ABS templates (corresponding to the first macro eNB and the second macro eNB).

WO2009 / 129261 discloses systems and methodologies that simplify resource management in a wireless communication system. A network cell in a wireless communication system (eg, a macro cell) is configured to mitigate the effect of interference on surrounding network cells (eg, femto cells within the coverage area of a macro cell). For example, a network cell may allocate control resources that overlap the control resources of a neighboring cell and assign resources within the overlap area only to users who will not cause significant interference to a nearby cell. As another example, a network cell may use the formation of a control channel, which partially coincides with the formation of a control channel and / or random access of a neighboring cell. The network cell may then select the option not to use control resources in the matching area to allow the neighboring cell to control the effects of interference when scheduling data.

SUMMARY OF THE INVENTION

The aim of the embodiments presented here is to improve the performance of a radio communication system, such as an LTE based radio communication system.

In accordance with an aspect, the goal is achieved by using a method in a network node to configure at least two patterns for a cell. Templates are transfer patterns or dimension patterns. A network node receives at least two patterns. Each of the at least two patterns is associated with a corresponding bounded area such that each pattern is used when a user device served by the cell is in a corresponding bounded area. Each corresponding limited region is smaller than the entire region of the cell.

According to another aspect, a goal is achieved by a network node to enable configuration of at least two patterns for a cell. Templates are transfer patterns or dimension patterns. The network node contains a processing circuit configured to receive at least two patterns. Each of the at least two patterns is associated with a corresponding bounded area, so that each pattern is used if the user device served by the cell is in a corresponding bounded area. Each corresponding limited region is smaller than the entire region of the cell.

In accordance with a further aspect, the goal is achieved by a method in a user device for configuring measurements. The user device is served by a hundredth radio base station. The user device receives at least two measurement patterns from the radio base station. Each measurement pattern is associated with a corresponding restricted area such that each pattern is used when the user device is in a corresponding restricted area. Each corresponding limited region is smaller than the entire region of the cell. In addition, the user device receives information about the corresponding limited area, thereby configuring measurements.

In accordance with another aspect, the goal is achieved using a user device for configuring measurements. The user device is configured to be served by a hundredth radio base station. The user device comprises a receiver configured to receive at least two measurement patterns from a radio base station. Each measurement pattern is associated with a corresponding restricted area such that each pattern is used when the user device is in a corresponding restricted area. Each corresponding limited region is smaller than the entire region of the cell. The user device further comprises a processing circuitry configured to obtain information about a corresponding restricted area. Thus, the user device is configured to configure measurements.

Due to the fact that at least two patterns can be configured for at least two corresponding restricted areas, the first pattern can be used for the first restricted area, and the second pattern can be used for the second restricted area.

When the patterns are transmission patterns, the first pattern allows transmission in more frames than the number of frames allowed for transmission in accordance with that defined by the second pattern. More frames provide more transmission options. This means that finding a frame for transmission is easier when the number of frames for transmission is greater.

When the patterns are measurement patterns, the first pattern allows measurement in more frames than the number of frames allowed for measurement in accordance with the definition of the second pattern. More frames provide more measurement options. This means that it is easier to find a frame for measuring when the number of frames for measurements is greater.

Therefore, the performance of the radio communication system using the second template can be improved compared to when the first template is used.

An advantage of the embodiments presented here is that they provide, for example, a less strict measurement configuration for user devices. This makes them more adaptive to the environment, interference and loading conditions within the cell or various groups of user devices. Embodiments further provide a more flexible configuration for macro cells. This allows for different patterns in different cells, which, in turn, significantly improves macro cell performance compared to the case when the same measurement pattern is used throughout the cell, a group of neighboring cells or all cells of the monitored area or the entire network.

An additional advantage of the embodiments presented herein is that they provide radio base stations that are aware of the pattern configuration in neighboring cells and / or nodes. In addition, embodiments provide communication patterns with both a predetermined and signalized description of at least one limited area where the pattern is applied.

BRIEF DESCRIPTION OF THE DRAWINGS

Various aspects of the embodiments disclosed herein, including specific features and their advantages, will be readily apparent from the following detailed description and the accompanying drawings, in which:

FIG. 1a-1e show ICIC schemes,

FIG. 2 shows a schematic overview illustrating an increase in cell range,

FIG. 3 shows a schematic overview of an exemplary radio communication system in which exemplary methods may be applied in accordance with embodiments proposed herein,

FIG. 4 shows a combined signaling circuit and a flowchart of exemplary methods performed in a radio communication system in accordance with FIG. 3

FIG. 5 shows a schematic overview of an exemplary radio communication system in which exemplary methods may be applied in accordance with the embodiments proposed herein,

FIG. 6a and FIG. 6b show combined signaling circuits and flowcharts of exemplary methods performed in a radio communication system in accordance with FIG. 5,

FIG. 7 shows a flowchart of the methods of FIG. 4 when viewed from the perspective of a network node.

FIG. 8 shows a block diagram of an exemplary network node configured to implement the methods illustrated in FIG. 7,

FIG. 9 shows a flowchart of the methods of FIG. 4 when viewed from a user device, and

FIG. 10 shows a block diagram of an exemplary user device configured to implement the methods illustrated in FIG. 9.

DETAILED DESCRIPTION OF THE INVENTION

Throughout the following description, similar reference numbers have been used to refer to similar elements, network nodes, parts, objects or features, where applicable. In the figures, features that appear in some embodiments are indicated by dashed lines.

FIG. 3 shows an example radio communication system 100, which in this example is an LTE system. In other examples, the radio communication system may be based on a global mobile communications system (GSM), universal mobile telecommunications system (UMTS), code division multiple access (CDMA), and the like.

The radio communication system 100 comprises a network node 140. The network node 140 may be a radio base station, a coordinating node, an operation and maintenance system (O&M), and the like. In embodiments where the network node 140 is a radio base station, it may be a macro eNodeB, a pico eNodeB, a micro eNodeB, a home eNodeB, and the like.

The radio communication system 100 comprises cells, such as cell C0 in FIG. 3. Cell C0 is controlled by a radio base station, such as network node 140. Thus, the radio communication system 100 may reflect a classic deployment, that is, pico base radio stations, etc. are absent. The embodiments presented here can also be implemented in macro / pico deployment, also referred to as heterogeneous deployment, which is described below and shown in FIG. 5.

At least two patterns may be configured for cell C0. At least two patterns are transfer patterns or measurement patterns. Patterns reflect the subframes available for transmission or measurement. A subframe is known from 3GPP terminology and typically has a duration of 1 ms. Thus, at least two patterns may relate to transmission power or transmission activity in a C0 cell.

At least two patterns may comprise a first pattern and a second pattern, respectively. The first and second patterns are associated with at least one of the following characteristics: bandwidth, transmit power levels, power reduction, and subframe properties. The first value of the at least one characteristic associated with the first pattern is different from the second value of the same characteristic associated with the second pattern.

When the patterns are dimension patterns, at least two dimension patterns may be different from each other. The first template can be designed for measurements at intervals, and the second template can be designed for measurements without intervals.

To provide increased flexibility for pattern configuration, cell C0 comprises a first region A1 and a second region A2. Thus, different patterns can be configured for or associated with different respective areas, as described in more detail below. For each area A1, A2, a corresponding template will be set. Cell C0 has an A0 region of the entire cell. Each of the first and second regions A1, A2 is smaller than the region A0 of the entire cell. The radio conditions in the first and second areas A1, A2 may differ for various reasons, such as buildings, background noise, etc.

The first region may, for example, be equal to the region A0 of the entire cell. In this case, the pattern for the second region replaces the pattern configuration for the entire cell, that is, the first region. This can improve backward compatibility.

The user device 130 is located within the cell C0. The user device 130 is called UE 130 in some figures. The user device 130 may be a mobile phone, cell phone, personal digital assistant (PDA) equipped with a radio function, a smartphone, a tablet PC, a tablet device, a laptop equipped with an internal or external broadband modem, portable electronic radio communication device, etc. User device 130 may be served by one or more additional cells (not shown).

When the network node 140 is the O&M coordinating node or system, the user device 130 is configured to communicate, as illustrated by arrow P1, with the network node 140 via a radio base station (not shown) via a radio link when the user device 130 is present in the cell C0 served base station.

When the network node 140 is a radio base station, the user device 130 is configured to communicate, as illustrated by arrow P1, with the radio base station, when the user device 130 is present in the cell C0 served by the radio base station.

FIG. 4 shows a combined message diagram and a flowchart of the methods implemented in the radio communication system in accordance with FIG. 3. Network node 140 performs a method for configuring at least two patterns for cell C0. The user device 130 performs a method for configuring measurements.

The following actions may be performed. It should be noted that in some embodiments of the method, the procedure may differ from what is indicated below.

ACTION 401

In some embodiments, the network node 140 obtains information about the corresponding limited area, such as the first and second areas A1, A2. As a result, the network node 140 is informed of the corresponding limited area.

Information about the corresponding restricted area can be obtained by one or more of the following methods of reading predetermined information about the corresponding limited area, generating information about the corresponding limited area, and receiving from another node. The other node may be a coordinating node, a pico or macro base radio station, or an Operation and Maintenance (O&M) system. These and other examples will be detailed below in list 2.

As an example, the network node 140 obtains information about the corresponding restricted area by generating the corresponding restricted area based on the detected overlap in the coverage area of two adjacent base stations.

Information about the relevant limited area will be used in further action and may relate to at least one of the following:

- a specific geographic area or direction;

- antenna configuration;

- an area with certain characteristics of the radio environment;

- the area defined in a certain way of the user device;

- the area associated with a particular signal level / quality and user device requirements (UE requirements);

- an area with certain performance characteristics; and

- the area defined by the capabilities of the user device or the location of the user device (capabilities of the UE or the location of the UE).

These and other examples will be discussed in detail below in list 1.

Information about the relevant limited area can be used to control interference, positioning, minimize automobile checks or SON.

ACTION 402

In order for network node 140 to be able to configure at least two patterns in cell C0, network node 140 receives at least two patterns.

Obtaining can be done by generating at least two patterns or receiving at least two patterns from another network node.

Each pattern is associated with information about a corresponding restricted area A1, A2 so that each pattern is used when the user device 130 is in a corresponding restricted area. Each respective access area A1, A2 is smaller than the entire area of cell C0.

As mentioned above, at least two patterns comprise a first pattern and a second pattern in accordance with some embodiments. In these embodiments, the implementation can be performed by generating the first pattern and receiving the second pattern. Thus, additional flexibility is achieved in obtaining at least two patterns.

ACTION 403

In some embodiments, the network node 140 further transmits at least two patterns to an additional network node or user device 130. The additional node may be a radio base station serving or not serving a user device, or a core network node, such as a coordinating node. Thus, an additional network node or user device can use at least two patterns that have been mentioned for transmission, measurement, or coordination purposes.

When the network node 140 is a radio base station, the additional network node may be a coordinating node. Thus, the network node 140 provides pattern information to a coordinating node, which can use this information to generate additional patterns for use in other cells. The coordinating node may also generate a new template, which is intended to replace one of the at least two templates. The coordinating node, of course, can also replace all of at least two patterns.

Alternatively or additionally, when the network node 140 is a radio base station, the additional network node may be another radio base station. Thus, the network node 140 provides template information to another radio base station, which can use this information as a transmission template. Typically, network node 140 has generated various patterns for own use and use by another radio base station.

When the additional network node is a user device 130, the transmission may be via broadcast, multicast, or dedicated transmission. In some examples, only one pattern is transmitted via dedicated transmission in response to a pattern configuration request, as explained in connection with FIG. 6b. In this way, broadcast or multicast is freed from the load when patterns are transmitted using dedicated transmission instead of broadcast or multicast. Typically, patterns transmitted to user device 130 are dimension patterns.

Information about the corresponding limited area may also be transmitted to another network node or user device 130 in this action.

ACTION 405

In some embodiments, the network node 140 additionally decides on the applicability of at least two patterns based on information about the corresponding limited area. As a result, the network node 140 determines which of the at least two patterns will be applied when the user device 130 is in a corresponding limited area. Typically, at least two patterns are transmission patterns in these embodiments.

Network node 140 may further decide on the applicability of at least two patterns based on available measurements related to the user device, such as position, current precoding, used bandwidth, etc. Thus, it is easier to determine in which corresponding limited area the user device is located.

ACTION 404

In order to inform the user device 130 which measurement patterns can be applied to various respective limited areas, the network node 140 sends at least two measurement patterns to the user device 130. They can be sent via a radio base station. As mentioned, each measurement pattern is associated with a corresponding bounded region and each corresponding bounded region is smaller than the entire region of the cell.

At least two measurement patterns may indicate when the user device 130 should take measurements in each corresponding limited area. By way of example, measurements are made with respect to a serving radio base station or an adjacent radio base station.

At least one of the at least two measurement patterns and corresponding limited area information may be received by the user device 130 via broadcast, multicast, or dedicated signaling from the network node 140, such as a radio base station serving the user device 130.

ACTION 406

In order for the user device 130 to be notified of the respective restricted areas, it receives information about the corresponding restricted area. In this way, measurements are configured using different measurement templates for different areas. Expressed differently, measurements are configured with different measurement patterns for different parts of the C0 cell.

Similar to the above, now for the user device 130, information about the corresponding limited area can be obtained by at least one of reading the predetermined information about the corresponding limited area, generating information about the corresponding limited area, and receiving from the network node 140. Network node 140 may be a radio base station, serving or not serving, or another node.

Similar to the above, now for the user device 130, information about the corresponding limited area may relate to at least one of:

- a specific geographic area or direction;

- antenna configuration;

- an area with certain characteristics of the radio environment;

- the area defined in a certain way of the user device;

- the area associated with a particular signal level / quality and user device requirements;

- an area with certain performance characteristics; and

- the area defined by the capabilities of the user device or the location of the user device.

Similar to the above, now for the user device 130, information about the corresponding limited area can be used to control interference, positioning, minimize automobile checks or SON.

ACTION 407

In some embodiments, the user device 130 further decides on the applicability of at least two measurement patterns based on information about the corresponding limited area.

Thus, the user device 130 determines which of the at least two measurement patterns will be used when the user device 130 is in a corresponding limited area. Typically, at least two patterns are measurement patterns in these embodiments.

The determination may be further based on at least one of the capabilities of the user device (capabilities of the UE) and available measurements related to the user device 130. Thus, it is easier to determine in which corresponding limited area the user device is located.

In formulating the concept of the embodiments proposed herein, the following was observed when examining macro / pico cell deployments and signaling measurement patterns and ABS patterns within such a deployment. The ABS pattern is an example of a gear pattern.

First, consider measurement patterns. In accordance with the current state of the art, a single measurement pattern per cell, such as a serving cell, should be determined. Although signal quality usually varies significantly across cell space, using a single measurement pattern per cell can work in practice when all potentially strong sources of interference, such as macro cells, use the same ABS pattern. However, loading typically varies widely between cells and ABS patterns will be associated with loading to optimize network performance. It is expected that different ABS patterns are configured in different cells, which may make it difficult or even impossible to determine that the same measurement pattern across the entire cell space is subject to strong interference from different cells in different parts of the cell.

The configuration of the most pessimistic measurement template for all user devices, that is, an indication of the resources that the user device can use for measurements when the user device is in any part of the cell, can result in a small set of resources being available for measurements. A small set of resources available for measurements increases the complexity of the user device, reduces the quality of measurements and increases the measurement time.

This will lead to much more liberal requirements for user devices configured with the most pessimistic measurement pattern compared to previous generation user devices. In other words, there is a need to resolve less stringent requirements for measurements performed by user devices configured with the most pessimistic measurement template. This, however, is not desirable since less stringent requirements reduce performance, for example, in terms of response time, for these user devices. The result is poor overall performance in heterogeneous networks due to an overly limited and inflexible configuration for measurement cases, such as the small set of resources available for measurements, as mentioned.

In classic network deployments, for example, without low-power nodes, such as pico base stations or home radio base stations (home eNodeBs), weakened user device requirements for measurement also result in poor overall performance. The reason is that in classic network deployments, also weakened or less stringent requirements for user devices with respect to measurements imply reduced performance, for example, in terms of response time, for user devices.

Secondly, when studying ABS patterns, it was revealed that another problem is that, according to the state of the art, only one ABS pattern is signaled. However, with advanced antennas adapted to dynamic antenna configuration methods, such as beamforming, transmit / receive diversity, distributed antenna systems and multicast transmit / receive, etc., linking a single ABS pattern to a cell will severely limit network performance. For example, although a cell transmits at some point in time, energy release and therefore potential interference to other cells can be significantly reduced in selected directions at that point in time, and directions can vary significantly over time. It discusses how transmission / reception directions can be associated with ABS patterns.

It is likely that a single measurement pattern will not be enough for intra-frequency and inter-frequency measurements. Also, a single measurement template is unlikely to be used for measurements of both the serving cell and neighboring cells, at least without observing some rules regarding when and what measurements should be performed using the measurement template provided for the user device.

Therefore, the embodiments presented here describe the use of at least two patterns, such as transmission patterns and measurement patterns for a cell. Each of the at least two patterns is associated with a corresponding limited area that is smaller than the entire area of the cell, as explained in more detail with reference to, for example, FIG. 3 and FIG. 5.

As discussed in the prior art section of the present disclosure, various interference coordination techniques, also referred to as ICICs (elICICs), have been considered in the context of heterogeneous network deployments. In order to ensure reliable operation for data and / or control channels, as well as to provide consistent measurements of user devices, such as mobility measurements, position measurements and channel estimation, in the presence of time-frequency radio resources with different conditions in terms of interference, the user device needs information, which provides him with the opportunity to derive resources for the listed dimensions. This not only simplifies user device measurements, but also maintains user device performance at an acceptable level. According to the current description of the standard, as provided by 3GPP, receiving such information by a user device is not possible. One might suggest communicating a template to a user device whose template reflects the subframes available for user device measurements.

Embodiments related to the aforementioned heterogeneous deployment will now be explained with reference to FIG. 5, which shows a radio communication system 100, which in this example is an LTE-based heterogeneous radio communication system. In other examples, a heterogeneous radio communication system may be based on a global mobile communications system (GSM), universal mobile telecommunications system (UMTS), code division multiple access (CDMA), and the like.

The radio communication system 100 comprises a macro radio base station 110 and a pico radio base station 120. Typically, the transmission power of the macro radio base station 110 is greater than the transmission power of the pico radio base station 120. The network node 140 shown in FIG. 3 may be illustrated by macro or pico radio base station 110, 120, as described in FIG. 6a and FIG. 6b. In addition, the radio communication system 100 comprises cells, such as a first cell C1 and a second cell C2. In each cell C1, C2, one or more patterns may be configured with reference, for example, to FIG. 6a and FIG. 6b.

Macro base station 110 controls the first cell C1 having a first integer region A5. The first whole region A5 can be divided into the first region A3 and the second region A4. As mentioned above, this provides increased flexibility in terms of template configuration. The first region A3 and / or the second region A4 is smaller than the first whole region A5.

The pico base station 120 controls a second cell C2 having a second integer region A6. The first whole region A6 can be divided into a third region A7 and a fourth region A8. Again, this provides increased flexibility in terms of template configuration. The third region A7 and / or the fourth region A7 is smaller than the second whole region A6.

The shapes of regions A3-A8 shown in FIG. 5 are purely schematic, and many other forms are possible. In addition, one or more areas A3-A8 can overlap each other.

In FIG. 5, the user device 130 is served by a pico radio base station 120. The user device in this example is located in the fourth region A8 of the pico radio base station 120. For example, the user device 130 may be a mobile phone, a cell phone, a personal digital assistant (PDA) equipped with a radio function, a smartphone , a tablet PC, a tablet device, a laptop equipped with an internal or external broadband modem, a portable electronic radio device, etc.

In FIG. 6 shows a combined signaling circuit and a flowchart of an exemplary method performed in the radio communication system 100 in accordance with FIG. 5. Here, the macro radio base station 110 is an example of a network node 140 of FIG. 3, and the first and second ABS patterns are examples of at least two patterns.

This example performs the following steps.

ACTION 601

In order for the macro base station 110 to be notified of the first and second areas A3, A4, the macro base station 110 receives information about the first and second areas A3, A4. Here, the first and second regions A3, A4 are examples of corresponding limited regions.

Obtaining can be carried out by reading information from a memory unit, that is, the information is predetermined. A memory unit is included in macro base station 110. These and other examples will be detailed below in list 2.

This action is performed similar to action 401.

ACTION 602

Macro base station 110 generates first and second ABS patterns for the first and second areas A3, A4, respectively. The first and second ABS patterns will be used when the user device 130 is in the first and second areas, respectively, as described in act 604.

With reference to the example of FIG. 5, the first ABS pattern associated with the first area A3 contains fewer nearly empty subframes than the number of nearly empty subframes contained in the second ABS template associated with the second area A4. The second ABS pattern is more restrictive, that is, it contains more nearly empty subframes than the first ABS pattern in order to reduce interference towards the user device 120 located in the second area A4.

This action is performed similar to action 402.

ACTION 603

Macro base station 110 sends at least one of the first and second ABS patterns to pico base station 120. Typically, a second ABS pattern is sent to pico base station 120 when it is located in second area A4. Thus, the pico base station 120 can determine its own ABS pattern, while taking into account the second ABS pattern. Alternatively, the macro base station 110 generates and sends an additional ABS pattern to be used by the pico base station 120. An additional ABS pattern is generated when at least the second ABS pattern is taken into account.

In addition, the macro base station 110 sends information about the second area when the second ABS pattern is sent to the pico base station 120. In addition, the macro base station 110 can send information about the first area, which corresponds to the first ABS pattern. Pico base station 120 may use information about the first and second areas to determine which of the first and second areas it is located. Thus, the determination by the pico base station 120 of its own ABS pattern is simplified.

This action is similar to action 403, when the additional node is the base radio station.

ACTION 604

Macro base station 110 decides on the applicability of at least two ABS templates based on information about the first and second areas A3, A4. By way of example, a macro base radio station 110 has the capability of generating an antenna pattern. Then, the macro base station 110 applies the first ABS pattern when the main lobe of the antenna pattern with respect to transmission is in the first direction from the macro base station 110. The first direction can be any within the first area A3. In addition, the macro base station 110 applies a second ABS pattern when the main lobe of the antenna radiation pattern with respect to transmission is in the second direction from the macro base station 110. The second direction can be any within the second area A4. Additional examples are presented below in list 1. This action is performed similar to action 405.

FIG. 6b illustrates a combined message diagram and a flowchart of another exemplary method performed in the radio communication system 100 in accordance with FIG. 5. Here, the pico base station 120 is an example of a network node 140 of FIG. 3.

ACTION 611

Macro base station 110 generates a transmission pattern (TX), the template of which will be sent to pico base station 120 at step 612, described below. This action is performed similar to action 402.

ACTION 612

Macro base station 110 sends a transmission pattern to pico base station 120. This action is performed similar to step 403.

ACTION 613

In some embodiments, the user device 130 sends a measurement pattern configuration request to, for example, the pico base station 120. Thus, the pico base station 120 can only generate and send the requested measurement pattern when the request also contains information on which area such as the fourth region A8, the user device 130 is located.

ACTION 614

The pico base station 120 generates at least a first and a second measurement pattern (Mx), while taking into account the transmission pattern. This transmission pattern can be configured for the first and second regions A3, A4 or only for the second region A4. Here, the first and second measurement patterns are examples of at least two measurement patterns.

The transmission pattern is taken into account in the sense that the first and second measurement patterns are associated with the third and fourth regions A7, A8, respectively. The third and fourth regions A7, A8 can be seen in FIG. 5. In this example, the first measurement pattern is less restrictive than the second measurement pattern when the third region A7 does not overlap with the second region A4. As a result, the first measurement pattern of the third area A7 does not need to be adjusted to fit almost empty subframes of the transmission pattern of the macro base station 110. In other words, the first measurement pattern is not designed to avoid interference from the macro base station 110, because, in accordance with with the first, second, third and fourth regions A3, A4, A7, A8, it is not expected that the transmission from the macro base station 110 will significantly affect the measurements performed by the user device 130 when it is located in third area A7.

In general, it may be desirable for the first and second measurement patterns to be generated so as to avoid transmission from the macro base station 110 indicated by the transmission pattern. Thus, the interference from the macro base station 110 towards the user device 130 is reduced when taking measurements.

This action is performed similar to action 402.

ACTION 615

In some embodiments, the pico base station 120 sends one of the first and second measurement patterns to user device 130. Typically, this action is performed in response to receiving a request for configuring measurement patterns, as illustrated in step 613. By receiving the request, multicast or broadcast can be avoided as mentioned above.

This action is performed similar to action 404.

ACTION 616

In some embodiments, the pico base station 120 broadcasts or sends in the form of broadcast or multicast first and second measurement patterns. Typically, measurement pattern broadcasts are performed when no request for configuration of measurement patterns is received by pico radio base station 120.

When a request is received by the pico radio base station 120, the first and / or second measurement pattern may be sent using a dedicated transmission. Consequently, multicast and broadcast transmissions are freed from the load.

This action is performed similar to action 404.

ACTION 617

The user device 130 makes a decision on the applicability of the first and second measurement patterns based on information about the third and fourth areas A7, A8. Information on the third and fourth areas A7, A8 may be predetermined, but other examples are also provided below. When the user device 130 determines which of the first and second measurement patterns will be applied, it can determine which of the third and fourth regions A7, A8 is in. This can be done using available measurements for positioning purposes. This action is performed similar to action 407.

It should be noted that the coordinating node for coordinating at least two patterns may in some examples generate at least two patterns. Further, templates and information about their limited areas are sent to, for example, a macro and / or pico base radio station.

Now, returning to the examples of FIG. 3 and FIG. 4, the methods will be described again, but when viewed from the perspective of the network node 140 and the user device 130, respectively. In addition, the configuration of the network node and the user device configured to implement the methods of FIG. 4 will be described in FIG. 8 and FIG. 10.

FIG. 7 shows a flowchart of a method in a network node 140, as shown in FIG. 4 to provide configuration for at least two patterns for cell C1. As mentioned above, the patterns are transfer patterns or dimension patterns. Network node 140 may be a radio base station, and cell C1 is controlled by a radio base station. Network node 140 may be a coordinating node.

The method comprises the following steps, which may be performed in any suitable order.

ACTION 701

In some embodiments, the network node 140 obtains information about the corresponding limited area, such as the first and second areas A1, A2. As mentioned above, information about the corresponding restricted area can be obtained by at least one of the following methods: reading predetermined information about the corresponding restricted area, generating information about the corresponding limited area, and receiving from an additional node. The additional node may be a pico / macro base station, a coordinating node, or an O&M system. These and other examples will be detailed below in list 2.

As mentioned above, information on a corresponding limited area may relate to at least one of:

- a specific geographic area or direction;

- antenna configuration;

- an area with certain characteristics of the radio environment;

- the area defined in a certain way of the user device;

- the area associated with a particular signal level / quality and user device requirements;

- an area with certain performance characteristics; and

- The area defined by the capabilities of the user device or the location of the user devices. These and other examples will be discussed in detail below in list 1.

This action is performed similar to action 401.

ACTION 702

Network node 140 receives at least two patterns. As mentioned above, each of the at least two patterns is associated with information about a corresponding restricted area A1, A2 so that each pattern is used when the user device 130 served by the cell C1 is in a corresponding restricted area. Each corresponding bounded region A1, A2 is smaller than the entire region of the cell C1.

At least two patterns may comprise a first pattern and a second pattern, the first and second patterns associated with at least one of the following characteristics: bandwidth, transmit power levels, power reduction, and subframe properties. The first value of the at least one characteristic associated with the first pattern is different from the second value of the same characteristic associated with the second pattern. Subframe properties may relate to MBSFN / non-MBSFN subframes.

Obtaining can be done by generating at least two patterns or receiving at least two patterns from another network node. At least two patterns may comprise at least two transmission patterns associated with transmission power or transmission intensity in cell C1. By way of example, transmission power may be lowered or increased. Alternatively or additionally, at least two patterns may comprise at least two measurement patterns.

As mentioned above, at least two measurement patterns may be different from each other. The first measurement template of at least two measurement templates is intended for measurements at intervals, and the second measurement template of at least two measurement templates can be designed for measurements without intervals.

This action is performed similar to action 402.

ACTION 703

In some embodiments, a network node 140 transmits at least two patterns to an additional network node or user device 130. The additional network node may be a pico / macro radio base station or a core network node, such as a coordinating node. A transmission may be a broadcast, multicast, or dedicated transmission. Network node 140 may further transmit information about a corresponding limited area. This action is performed similar to action 403.

ACTION 704

Network node 140 may further transmit at least two measurement patterns. This action is performed similar to action 404.

ACTION 705

In some embodiments, the network node 140 decides on the applicability of at least two patterns based on information about the corresponding limited area. This action is performed similar to action 405.

FIG. 8 shows a block diagram of an example network node 140 that is configured to implement the method illustrated in FIG. 7. The network node 140 is configured to configure at least two patterns for cell C1. As mentioned above, the patterns are transfer patterns or dimension patterns. Network node 140 may be a radio base station, such as a macro or pico radio base station 110, 120, and cell C1 is controlled by a radio base station. Network node 140 may, in other examples, be a coordinating node, such as O&M.

Network node 140 comprises a processing circuit 810 configured to receive at least two patterns. Each of the at least two patterns is associated with a corresponding restricted area A1, A2 so that each pattern is used when the user device 130 served by the cell C1 is in a corresponding restricted area. Each corresponding bounded region A1, A2 is smaller than the entire region of the cell C1.

The processing circuit 810 may further be configured to generate at least two patterns or receive at least two patterns from another network node.

At least two patterns may comprise a first pattern and a second pattern, the first and second patterns associated with at least one of the following characteristics: bandwidth, transmit power levels, power reduction, and subframe properties. The first value of the at least one characteristic associated with the first pattern is different from the second value of the same characteristic associated with the second pattern.

At least two patterns may comprise at least two transmission patterns associated with transmission power or transmission intensity in cell C1. Alternatively or additionally, at least two patterns may comprise at least two measurement patterns.

As mentioned above, at least two measurement patterns may be different from each other. The first measurement template of at least two measurement templates is intended for measurements at intervals, and the second measurement template of at least two measurement templates can be designed for measurements without intervals.

The processing circuit 810 may further be configured to obtain information about the corresponding restricted area using at least one of the following: reading predetermined information about the corresponding limited area, generating information about the corresponding limited area, and receiving from another node.

Information about the relevant limited area may relate to at least one of the following:

- a specific geographic area or direction;

- antenna configuration;

- an area with certain characteristics of the radio environment;

- the area defined in a certain way of the user device;

- the area associated with a particular signal level / quality and user device requirements;

- an area with certain performance characteristics; and

- the area defined by the capabilities of the user device or the location of the user device.

In some embodiments, the processing circuit 810 is further configured to decide on the applicability of at least two patterns based on information about a corresponding bounded area.

Information about the relevant limited area can be used to control interference, positioning, minimize vehicle checks or SON.

The processing circuit 810 may be a processor unit, a processor, a specialized integrated circuit (ASIC), a field programmable gate array (FPGA), or the like. As an example, a processor, ASIC, FPGA, etc. may contain one or more processor cores.

Network node 140 further comprises a transmitter 820, which in some embodiments is configured to transmit at least two patterns to another network node or user device 130.

Transmitter 820 may further be configured to transmit by broadcast, multicast, or dedicated transmission. When the transmitter 820 is configured to transmit via a dedicated transmission, transmission is allocated to the user device 130.

Transmitter 820 may further be configured to transmit information about a corresponding restricted area.

Network node 140 further comprises a receiver 830, which in some embodiments is configured to receive measurement reports from user device 130. Receiver 830 may be configured to receive measurement configuration request from user device 130.

The network node 140 further comprises a memory unit 840 for storing software that is to be implemented, for example, by a processing circuit. The software may contain instructions to enable the processing circuit to execute the method on the network node 140, as described above with respect to FIG. 7. The memory unit 840 may be a hard disk, a magnetic storage medium, a portable computer diskette or disk, flash memory, random access memory (RAM), and the like. In addition, the memory unit may be processor internal memory.

FIG. 9 shows a flowchart of a method in a user device 130, as shown in FIG. 4, for configuration measurements. The user device 130 is served by the hundredth C1 of the radio base station. The method comprises the following steps, which may be performed in any suitable order.

ACTION 901

User device 130 may receive at least two patterns. This action is performed similar to action 403.

ACTION 902

User device 130 receives at least two measurement patterns from a radio base station. Each measurement template is associated with a corresponding limited area so that each measurement template is used when the user device 130 is in the corresponding limited area. As mentioned above, each corresponding bounded region is smaller than the entire region of the cell.

As mentioned above, at least one of the two measurement patterns and information about the corresponding limited area may be received as broadcast, multicast, or dedicated transmission.

At least two measurement patterns may comprise a first pattern and a second pattern. The first and second patterns may be associated with at least one of the following characteristics: bandwidth, transmit power levels, power reduction, and subframe properties. The first value of the at least one characteristic associated with the first pattern is different from the second value of the same characteristic associated with the second pattern.

This action is performed similar to action 404.

ACTION 903

The user device 130 obtains information about the corresponding limited area, thereby configuring measurements.

As mentioned above, the user device 130 can obtain information about the corresponding restricted area using at least one of the following: reading predetermined information about the corresponding limited area, generating information about the corresponding limited area, and receiving from another node.

Information about the relevant limited area may relate to at least one of:

- a specific geographic area or direction;

- antenna configuration;

- an area with certain characteristics of the radio environment;

- the area defined in a certain way of the user device;

- the area associated with a particular signal level / quality and user device requirements;

- an area with certain performance characteristics; and

- the area defined by the capabilities of the user device or the location of the user device.

At least two measurement patterns may reflect when the user device 130 is to take measurements in each corresponding limited area.

This action is performed similar to action 406.

ACTION 904

In some embodiments, the user device 130 decides on the applicability of at least two measurement patterns based on information about the corresponding limited area.

The definition may further be based on at least one of the following: user device performance and available measurements related to user device 130.

This action is performed similar to action 407.

FIG. 10 shows a block diagram of an example user device 130 configured to perform the method illustrated in FIG. 9. The user device 130 is configured to configure measurements. To put it differently, the user device 130 is configured to set measurement patterns to be used when the user device is in various limited areas of the cell. The user device 130 is also configured to be served by a hundredth C1 of a radio base station.

The user device 130 comprises a receiver 1010 configured to receive at least two measurement patterns from a radio base station. As mentioned above, each measurement template is associated with a corresponding limited area so that each measurement template is used when the user device (130) is in the corresponding limited area. As mentioned above, each corresponding bounded region is smaller than the entire region of the cell.

Measurement patterns may reflect when the user device 130 is to take measurements in each corresponding limited area.

As mentioned above, at least two measurement patterns may comprise a first pattern and a second pattern. The first and second patterns may be associated with at least one of the following characteristics: bandwidth, transmit power levels, power reduction, and subframe properties. The first value of the at least one characteristic associated with the first pattern is different from the second value of the same characteristic associated with the second pattern.

In some embodiments, receiver 1010 is further configured to receive, by broadcast, multicast, or dedicated transmission, at least one of the following: at least two measurement patterns and information about a corresponding limited area.

Information about the relevant limited area may relate to at least one of the following:

- a specific geographic area or direction;

- antenna configuration;

- an area with certain characteristics of the radio environment;

- the area defined in a certain way of the user device;

- the area associated with a particular signal level / quality and user device requirements;

- an area with certain performance characteristics; and

- the area defined by the capabilities of the user device or the location of the user device.

In addition, the user device 130 comprises a processing circuit 1020 configured to obtain information about a corresponding limited area, whereby the user device 130 is configured to configure measurements. The processing circuit 1020 may further be configured to obtain information on a corresponding restricted area in at least one of the following ways: reading predetermined information on a corresponding limited area, generating information on a corresponding limited area, and receiving from a radio base station or other node.

The processing circuit 1020 may further be configured to decide on the applicability of at least two measurement patterns based on information about the corresponding limited area.

The processing circuit 1020 may further be configured to decide on the applicability of at least two patterns based on at least one of the following: user device performance or available measurements related to user device 130.

The processing circuit 1020 may be a processor unit, a processor, a specialized integrated circuit (ASIC), a field programmable gate array (FPGA), or the like. As an example, a processor, ASIC, FPGA, etc. may contain one or more processor cores.

The user device 130 further comprises a transmitter 1030, which in some embodiments is configured to transmit reports related to measurements performed in accordance with the configured measurement template or measurement templates. A transmitter 1030 may be configured to transmit a measurement configuration request.

The user device 130 further comprises a memory unit 1040 for storing software that is to be implemented, for example, by a processing circuit. The software may contain instructions to enable the processing circuit to execute the method in the user device 130, as described above using FIG. 9. The memory unit 1040 may be a hard disk, a magnetic storage medium, a portable computer diskette or disk, flash memory, random access memory (RAM), and the like. In addition, the memory unit may be processor internal memory.

In general, the present disclosure relates to methods and circuits in wireless telecommunication systems, and in particular, the present disclosure relates to methods and circuits that use patterns that determine the transmission rate of at least some transmitting devices, where the receiving nodes also use certain patterns for their measurements.

The embodiments presented here relate to methods and schemes that provide transmission intensity and application of measurement patterns in limited areas that are less than the entire planned cell coverage area. These templates are hereinafter referred to as limited use ABS templates and limited use measurement templates.

Certain embodiments presented herein define the scope of application restrictions for ABS and transmission patterns and relate the area to these patterns. Embodiments also include node functionality associated with defining or linking to restricted areas. Additionally, embodiments include one or more signaling circuits configured to provide limited use patterns. Finally, embodiments include predefined rules that associate a template with a limited area and / or hundredth.

Finally, one or more embodiments allow the use of limited area information for other purposes, including SON, positioning, minimizing automobile checks, etc.

The following terms and generalizations are used throughout this disclosure:

Type of network. Examples of network types are heterogeneous, macro / picot, traditional and classic network deployments. The methods and schemes disclosed herein have been primarily created for, but are not limited to, heterogeneous deployments. The methods and schemes are also not limited to any definition of 3GPP regarding deployments of heterogeneous networks. For example, the methods and schemes could be well adapted to traditional deployments, also referred to here as classic deployments, and / or networks that manage more than one radio access technology (RAT). Although the methods and schemes are mainly designed for cellular networks with a transmitting node that transmits on the downlink (DL), the methods and schemes are generally applicable to any network where different nodes use different transmit power and can configure their transmission patterns. Such a network can also be a specialized network or a network that unrolls device-to-device communication, or a wireless network with a node coverage determined on the basis of the received signal power.

Transmitting node. The sending node is commonly referred to here as an eNodeB. However, the transmitting node can generally comprise any radio network node capable of transmitting radio signals, for example, macro eNodeB, pico eNodeB, micro eNodeB, home eNodeB, relay nodes, etc.

Receiving node. The receiving node is commonly referred to herein as a user device. However, the receiving node in general may comprise any radio device capable of receiving radio signals, for example, user devices, PDAs, laptops, repeaters, etc.

Transmission intensity pattern. The transmission rate pattern is commonly referred to herein as an almost empty subframe (ABS) pattern. In general, however, a transmission intensity pattern is a configuration of a transmission intensity defined for a node for a specific period of time. ABS refers to one or more points in time with an ABS template, where transmission intensity is lower than in non-ABS subframes. Here, “lower” means either transmission at a lower power level or no transmission at all for certain channels / signals or all transmissions. Although emphasis is placed on reduced transmission intensity, an indication of increased transmission intensity may also be used, for example, to indicate potentially severe interference from a corresponding node. The ABS pattern may or may not include other patterns, for example, MBSFN subframes configured as ABS, and may or may not be part of the ABS pattern, as determined by the network or in accordance with a predetermined behavior of network nodes. The ABS pattern may be determined by the carrier in frequency, and therefore, several patterns may then be created for several carriers, or the same ABS pattern may also be used for more than one cell or carrier associated with the same eNodeB. ABS can also be configured for a specific part of the system bandwidth. For example, six resource blocks centered on a DC carrier, or any bandwidth centered on a carrier bandwidth, are concentrated in a multi-carrier system. In another embodiment, the power reduction, for example, compared with non-ABS subframes in the same template or compared with the maximum absolute cell power level that is applied in ABS, for example, a general reduction in transmit power for all channels / signals or for specific reference signals or control channels or control areas or data areas, reported together with ABS. ABS templates and such additional information as, for example, bandwidth, frequency, power reduction in ABS, can be reported, for example:

- from the transmitting node to the receiving node, for example, via RRC, where the user can determine whether to calculate the ABS, for example, as described for multicast broadcasting and broadcasting, and the corresponding information, or

- from a transmitting node to more than one receiving node by means of a multicast or broadcast message, where a group of receiving nodes is determined, for example,

- a network that, for example, uses the multicast channel received by the target group,

- a user device, for example,

- ABS and information associated with it are applied to user devices in an enlarged part of the cell, that is, to user devices using a snap to offset cells. Such a user device behavior may be predetermined,

- when the difference between the power level of the received signals or the quality level of the received signal of the interfering cell and similar indicators of the serving cell exceeds a certain threshold value.

- between two transmitting nodes, for example on X2 or using the O&M system.

A measurement template is a template that indicates to the user device when measurements should be taken. A measurement type may be associated with a measurement template, for example, 'RRM', 'RLM', 'RLF', 'CSI', etc., which may be communicated with the template or may be predetermined. RLF stands for Radio Link Failure. Measurements are usually taken with respect to the serving cell, so it is expected that the measurement is associated with the serving cell. A measurement pattern for a serving cell may or may not be applicable for measuring neighboring cells, and thus a set of measurement patterns may be provided in combination with a set of cells. The means for signaling the measurement pattern and the user device behavior may be the same as for the ABS pattern. However, the user device will be able to understand that if the ABS template for cell 1 reflects the times when the cell is not transmitting, then these moments will be excluded from a number of measurement situations for this cell, or, on the other hand, they will be considered potential situations for measurements of another cell, cell 2, for which cell 1 is a strong source of interference. Similarly, a measurement pattern will be clearly associated with a cell, for example, it may be good for measuring a serving cell, but may not be very good for measuring neighboring cells. The binding may, for example, be an explicit signaling of the cell ID along with a template or predetermined (for example, always for a serving cell or for cells at the same node level as the serving cell, where the level may relate to a power class such as pico, micro , macro BS, and / or for cells at the same frequency). The measurement pattern may also be communicated with related information, such as bandwidth and frequency. For the same user device, there may also be different rules for defining and applying patterns for measurement with and without intervals (for example, intra-frequency measurement versus inter-frequency, or on another carrier component (other carrier component) that is activated, versus one that is deactivated , intra-RAT vs. inter-RAT). Alternatively, various patterns may be explicitly communicated to the user device for measurements with and without intervals. The described aspects of pattern binding to cells and patterns for measuring with / without intervals are also discussed here, and they may or may not be combined with options for implementing a limited area, that is, the restriction application now applies to measurement types and cells.

As discussed here, templates are created with limited application and relationship to templates. An ABS template or measurement template is associated with a specific area.

A restricted area is an area that is smaller than the planned coverage area of the entire cell or area associated with a subset of user devices (for example, related to user device performance). Limited areas can also geographically overlap.

The entire planned coverage area is usually determined, but not limited to this definition, taking into account the binding to the cells based on the level of the received signal. That is, the planned cell coverage area is the area where the received cell signal level is the highest among neighboring cells detected, taking into account the transmit power configuration (usually the maximum), the default transmit antenna configuration and the normal receiver configuration, for example, a user device with an omnidirectional antenna. Some selection of offset cells with predetermined offsets for a given set of cells, for example, 10 dB offsets for pico cells to increase pico cell coverage, can be considered when determining the intended cell coverage area. In general, any default network configuration can be considered when referring to a planned cell coverage area.

Different patterns or different types of patterns may also be associated with different limited areas. For example, pattern 1 with better interference conditions for user device measurements may be associated with one restricted area, and pattern 2 with poorer interference conditions may, on average, be associated with another limited area, for example, where CRE is not applied. These various patterns or types of patterns can also be used for previous generation user devices (specific version) or user devices with minimal performance. Pattern 1 may be a pattern composed of MBSFN subframes, and pattern 2 may be composed of non-MBSFN ABS subframes or a mixture of empty subframes with various properties.

Various embodiments related to the definition of a limited area and corresponding nodes are further described in this part.

Limited area. A limited area may relate, for example, to any one or more of the aspects below, or a combination thereof.

LIST 1

- A specific geographic area, for example, based on:

- location information of the user device,

- synchronization positioning measurements (timing advance, RSTD, ToA), which generally relate to distance,

- the direction of the location of the user device (location of the UE). For example, measuring the angle of arrival (AoA measurement) or any direction of arrival information,

- proximity information, for example, proximity to a particular type of radio nodes, such as home eNodeBs, pico cells, cells of a closed subscriber group (CSG cells), etc.,

- antenna configurations, for example,

- the direction of the main (transmitting) beam of the radiation pattern of the antenna system in the cell eNodeB, or

- the direction of the main (receiving) beam of the radiation pattern of the antenna system of the user device,

- precoding information for the transmitting antenna system eNodeB,

- precoding information received by the receiving node.

Here, the direction can be configured / known (for example, on the eNodeB: antenna tilt / azimuth configuration, codebook index, precoding matrix, etc.) or evaluated. For example, the direction of the strongest interference source estimated by the user device, the precoding matrix or indicator of the precoding matrix estimated by the user device, and also the feedback from the network. The direction may also be absolute, for example, latitude, longitude, or relative, for example, with respect to the main beam of the antenna pattern, or may be reflected using a precoding matrix or index indicating a pre-determined precoding configuration.

- An area with certain characteristics of the radio environment, for example,

- the internal environment, which can be explicitly indicated, for example, by the user device, or found by the network, for example, based on available statistics and / or received measurements of the UE.

- An environment identified as “complex”, for example, based on:

- measurements of the user device from the serving cell, such as statistics of the report on the measurement failure, high error rate, large spread in delay, low ratio of signal level to the total level of mutual interference and noise (SINR), etc.,

- combinations of user device measurements from several cells (example: RSRP from cell 1, RSRP from cell 2 and RSRP from cell 3),

- measurements collected from many user devices, where measurements can also be associated with RF fingerprint, adaptive enhanced cell ID (AECID) cards,

- the number of strong sources of interference (for example, the signal level is above a certain threshold value),

- the relationship between the power levels of the received signal among neighboring cells (for example, the difference between the interference source and the server is greater than a certain threshold value).

- An area defined by a particular user device action, for example,

- selection of the offset cell, when the user device may be associated with the cell weaker than the interfering neighboring cell, and it may be that not all user cells can use the selection of the offset cell or not to the maximum allowed range, for example, determined by the maximum absolute offset in 24 dB the solution may be based on the performance of the user device, a specific version of the user device, the ability to suppress interference, the category of the user device, etc.,

- the area associated with a certain signal level / quality and user device requirements that may be associated with certain properties of the diagram, such as the frequency of blanking and the density of blanking of the chart;

- an area with certain performance characteristics, for example:

- an area where many radio link failures can occur,

- area with many dropped calls,

- handover areas,

- areas that are relatively powerful (for example, compared with some threshold value (some threshold values)), signals are received from cells associated with a certain power class of the base station (for example, pico and macro),

- areas that are relatively powerful (for example, in comparison with a certain threshold value (some threshold values)), signals are received from at least some predetermined number of cells, while the number of cells can be further detailed using the BS power class (for example, ≥2 detected and relatively powerful / close macro cells in the area where the user device is served by picocell).

- An area defined by the capabilities of the UE, for example, where a limited area can overlap and each limited area is associated with a subset of user devices.

In one embodiment, limited area information, as described above, is used to control interference in heterogeneous network environments.

In another embodiment, this information is used for positioning and other purposes, such as minimizing car checks, checking the network and user device, SON, etc. The use of information may include using it to group user devices in accordance with the criteria of the corresponding limited areas, which for positioning purposes can be used, for example, to create auxiliary data, to configure the muting of signals used for positioning measurements or in the logic of choosing a positioning method. Use to minimize automotive checks may include the selection of user devices that report measurements to achieve this goal, or can act as a condition for initiating measurement messages to achieve this goal, for example, when finding or entering an appropriate limited area.

A limited area can be obtained by a user device or network node, as specified by the context, in one or more of the following ways:

LIST 2

- Predefined, for example, in accordance with basic requirements or performance requirements or a specific course of action.

Example 1: a measurement pattern is associated with an enlarged cell region (for example, for which the cell selection offset or offset is greater than a predetermined threshold value, for example 10 dB); in addition, a certain number of empty subframes in the template can also be associated with a certain threshold value, for example, in accordance with the requirements of applicability.

Example 2: the minimum SINR at which a user device may not need to use a template and dropping below which initiates the use of a template.

- Defined only by the user device, for example, based on the performance of the user device and / or available measurements, that is, the user device determines whether the area is critical and whether template configuration is required or the network sends templates to all user devices, but user devices determine whether to apply when and how data patterns. The determination criteria may be the quality level of the signal currently observed, identified by a group of neighbors, etc. and may be implementation dependent.

- A configured eNodeB (where a generally configured condition is either communicated to the user device in order to support the user device, or only the eNodeB is used to determine which user devices the template needs to communicate to, for example, via the RRC protocol).

Example 1: the minimum SINR defined by the eNodeB at which the user device may not need to use the template and dropping below which initiates the use of the template; the pattern may be communicated to user devices that report bad SINRs, or the SINR level may be communicated to the user device along with the pattern to simplify the definition of the user device.

Example 2: a template is relevant for a user device near a home eNodeB controlling a CSG cell not selected by the user device. Thus, it is subject to powerful interference from the eNodeB, but without the possibility of reverse sampling, not being part of the CSG. A list of such CSG cells can be determined by the eNodeB for the user device along with a proximity condition (for example, a threshold value for a received signal or SINR).

Example 3: the location within the specific area where the template will be used, and the area is determined by the eNodeB; the location may be communicated with the template or the eNodeB may signal to user devices that are estimated to be within a specific area.

Example 4: user devices within a certain angle of the sector defined by the eNodeB, concentrated in the direction of the main lobe of the picocell antenna pattern, do not need to use a template, which may be the decision of the user device whether to use or not use templates, or the eNodeB solution as to whether or not to transmit the template.

Example 5: user devices that do not measure in the direction (s) defined by the eNodeB may not use patterns (“forbidden” directions can be determined by the eNodeB, for example, based on the collection of PMI measurements from several user devices and the corresponding signal quality measurement statistics).

“Prohibited” directions can be communicated to the user device along with a template, while “prohibited” directions can be expressed using one or more precoding matrices or indices pointing to precoding matrices;

Alternatively, the pattern (s) may (may) be sent to user devices for which the notified PMI reflects that the UE is close to the “forbidden” direction (s), or may (may) not be sent to other user devices.

- Configured by the main eNodeB, for example, a macro eNodeB, is communicated to a group of linked cells, for example, pico cells in the coverage area of the macro cell in question, for example, via the X2 interface.

- Configured by a coordinating network node that dynamically communicates with the eNodeB group.

- Configured semi-statically O&M and communicated via the eNodeB / O & M interface to the eNodeB.

It should be understood that a node, such as a network node involved in the definition of templates, will usually be able to perform one of the following actions:

- receive information about a limited area, while receiving means receiving information from other nodes or local generation based on other available information or on the basis of other information received from other nodes,

- generate a template associated with at least one limited area,

- generate a combined template for two or more limited areas,

- report to other nodes, such as a user device or network nodes, a template associated with information about a limited area,

- accept the template associated with at least one limited area,

- decide on the applicability of the template defined by the available information about the limited area, for example, accessible locally from measurements or other sources or received from other nodes and / or taken together with the template,

- associate a measurement template with a cell based on information about a limited area,

- update the template in the case associated with changing a limited area (for example, changing the configuration of the antenna or moving the user device to another location).

Signaling for message templates with limited use may include:

- X2AR (protocol on the X2 interface);

- RRC (protocol on the Uu interface), which can be allocated or associated with a cell or associated with a region and signaling with information about the corresponding limited region (defined in advance or communicated, as described above);

- Signaling on the interface between the eNodeB and O&M or the coordinating network node;

- S1AP (protocol on the X2 interface): if it is considered preferable to send this information between eNBs that do not have an available X2 interface, it can also be communicated as part of the transmission of SON information already available on the S1 interface, or it may be new signaling on this interface.

In the X2 signaling example, several patterns of limited use could be transmitted for each cell served by the macro and / or pico eNB using the LOAD indication procedure. More specifically, an eNB macro could send a LOAD INFORMATION message to a pico eNB, and such a message may contain a new piece of information, for example, a limited use ABS template IE. This new IE could contain templates and constraint information for each element. The constraint information may be a description of the restricted areas defined above.

Alternative coding options are possible, which could not affect the relevance of the disclosed method.

Although embodiments of various aspects have been described, many other changes, modifications, and the like will be apparent to those skilled in the art. The described embodiments are therefore not intended to limit the scope of the present disclosure.

Claims (21)

1. A method in a network node (110, 120, 140) for configuring at least two transmission patterns for a cell (C1), comprising:
obtaining (402, 702) at least two transmission patterns, wherein at least two transmission patterns relate to one or more subframes in which transmission is carried out at a reduced power level, and relate to downlink transmission patterns to reduce interference in towards a user device (130) located in another cell (C2), each transmission pattern being associated with information about a corresponding limited area (A1, A2), and each transmission pattern is subject to the use of a network node (110, 120, 140) for transmission in the corresponding restricted area, wherein each bounded region corresponding (A1, A2) is less than the whole cell area (C1). 2. The method of claim 1, wherein the network node (110, 120) is a radio base station and the cell (C1) is controlled by a radio base station. 3. The method of claim 1, wherein the network node (140) is a coordinating node. 4. The method according to any one of paragraphs. 1-3, additionally containing:
transmitting (403, 703) at least two transmission patterns to another network node or user device (130). 5. The method of claim 4, wherein the transmission (403) comprises transmission by broadcast or multicast. 6. The method according to claim 5, in which the transmission (403) further comprises transmitting information about the corresponding limited area. 7. The method according to claim 6, in which information about the corresponding limited area refers to at least one of the following:
- a specific geographic area or direction;
- antenna configuration;
- an area with certain characteristics of the radio environment;
- the area associated with a certain level / quality of the signal;
- an area with certain performance characteristics; and
- The area specified by the location of the user device. 8. The method according to claim 7, in which information about the corresponding limited area is used to control interference, positioning, minimize automobile checks or SON. 9. The method according to claim 7, in which information about the corresponding limited area is obtained by at least one of:
reading predetermined information about the corresponding limited area;
generating information about the relevant limited area;
receive from another node. 10. The method according to any one of paragraphs. 1-3, 5-9, further comprising:
making a decision (405, 705) on the applicability of at least two templates based on information about the corresponding limited area. 11. A network node (110, 120, 140) to configure at least two transmission patterns for a cell (C1), wherein the network node (110, 120, 140) comprises:
a processing circuit (810) configured to receive at least two transmission patterns, wherein at least two transmission patterns relate to one or more subframes in which transmission is carried out at a reduced power level, and relate to downlink transmission patterns to reduce interference in the direction of the user device (130) located in another cell (C2), each of at least two transmission patterns associated with a corresponding limited area (A1, A2), each the transmission pattern is to be used by the network node (110, 120, 140) when transmitting in the corresponding limited area, with each corresponding limited area (A1, A2) less than the entire area of the cell (C1). 12. The network node (110, 120, 140) according to claim 11, wherein the network node (110, 120) is a radio base station, and the cell (C1) is controlled by a radio base station. 13. The network node (110, 120, 140) according to claim 11, wherein the network node (140) is a coordinating node. 14. The network node (110, 120, 140) according to claim 11, wherein the processing circuit (810) is further configured to generate at least two transmission patterns or receive at least two transmission patterns from another network node. 15. The network node (110, 120, 140) according to any one of paragraphs. 11-14, further comprising a transmitter (820) configured to transmit at least two transmission patterns to another network node or user device (130). 16. The network node (110, 120, 140) according to claim 15, wherein the transmitter (820) is further configured to transmit by broadcast or multicast. 17. The network node (110, 120, 140) according to claim 16, wherein the transmitter (820) transmitting (403) further transmits information about a corresponding limited area. 18. The network node (110, 120, 140) according to claim 17, in which information about the corresponding limited area refers to at least one of the following:
- a specific geographic area or direction;
- antenna configuration;
- an area with certain characteristics of the radio environment;
- the area associated with a certain level / quality of the signal;
- an area with certain performance characteristics; and
- The area specified by the location of the user device. 19. The network node (110, 120, 140) according to claim 18, wherein the information about the corresponding limited area is used to control interference, positioning, minimize automobile checks, or SON. 20. The network node (110, 120, 140) according to claim 18, in which the processing circuit (810) is further configured to receive information about a corresponding limited area by at least one of:
reading predetermined information about the corresponding limited area;
generating information about the relevant limited area;
receive from another node. 21. The network node (110, 120, 140) according to any one of paragraphs. 11-14, 16-20, in which the processing circuit (810) is further configured to decide on the applicability of at least two patterns based on information about the corresponding limited area.

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