KR20130104333A - Apparatus and method for controling in-device coexistence interference in wireless communication system - Google Patents

Abstract

PURPOSE: An IDC control apparatus in a wireless communication system and a method thereof are provided to trigger the generation of IDC regarding a frequency band which is set up by a network or a frequency band which is not set up by a network. CONSTITUTION: A transmission unit (2220) transmits terminal performance information including frequency information capable of generating IDC. An identification unit (2210) identifies whether the frequency band capable of generation IDC is a frequency band which is set up by a network or not. A reception unit (2205) receives setup information about measuring and triggering regarding the frequency band capable of generating IDC from a base station. A measuring and triggering unit (2215) performs measurement and triggers IDC based on the identification result and the setup information about measuring and triggering. [Reference numerals] (2205,2255) Reception unit; (2210) Identification unit; (2215) Measuring and triggering unit; (2220,2270) Transmission unit; (2260) Selection unit; (2265) IDC solution unit; (AA) RRC connection reset message; (BB) IDC solution; (CC) Nearing instruction message; (DD) IDC instruction information measurement results

Description

Apparatus and method for controlling in-device coexistence interference in a wireless communication system {APPARATUS AND METHOD FOR CONTROLING IN-DEVICE COEXISTENCE INTERFERENCE IN WIRELESS COMMUNICATION SYSTEM}

The present invention relates to a wireless communication system, and more particularly, to an apparatus and method for controlling in-device coexistence interference in a wireless communication system.

Wireless communication systems generally use one bandwidth for data transmission. For example, a second-generation wireless communication system uses a bandwidth of 200 KHz to 1.25 MHz, and a third-generation wireless communication system uses a bandwidth of 5 MHz to 10 MHz. To support increasing transmission capacity, the recent 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) or Institute of Electrical and Electronics Engineers (IEEE) 802.16m continues to expand its bandwidth to 20 MHz or more. Increasing the bandwidth to increase the transmission capacity is essential, but supporting large bandwidths even at low levels of required services can result in large power consumption.

Accordingly, a multiple component carrier system has emerged, which defines a carrier having one bandwidth and a center frequency and enables data to be transmitted or received over a wide band through a plurality of carriers. By using one or more carriers, both narrow and wide bandwidths are supported simultaneously. For example, if one carrier corresponds to a bandwidth of 5 MHz, four carriers support a maximum bandwidth of 20 MHz.

Today's ubiquitous access network allows users to connect to different networks in different regions and maintain connectivity anywhere. A user in which one terminal communicates with one network system carries different devices supporting each network system. However, in recent years, as the functions of a single terminal have been advanced and complicated, communication with multiple network systems can be performed simultaneously with only one terminal, and user convenience has been increased.

However, when one terminal simultaneously communicates on multiple network system bands, In-Device Coexistence interference (IDC) may occur. In-device coexistence interference refers to interference when transmission in one frequency band interferes with reception in another frequency band in the same terminal. For example, when a terminal simultaneously supports a Bluetooth system and an 802.16 system, in-device coexistence interference may occur between the Bluetooth system band and the 802.16 system band. In-device co-existence interference can occur mainly when the spacing between frequency band boundaries of heterogeneous network systems is not wide enough.

However, in the current wireless communication system, a specific method for coordinating in-device coexistence interference has not been determined. In other words, there is a need for a procedure regarding an operation for resolving in-device coexistence interference between a terminal and a base station.

An object of the present invention is to provide an apparatus and method for controlling coexistence interference in a device.

Another object of the present invention is to provide an apparatus and method for triggering occurrence of in-device coexistence interference with respect to a frequency band set by a network or a frequency band not set by a network.

Another object of the present invention is to provide a method and apparatus for transmitting and receiving an indication operation related to in-device coexistence interference.

According to an aspect of the present invention, a method of controlling in-device coexistence interference (IDC) by a terminal in a wireless communication system includes transmitting terminal capability information including frequency information capable of generating IDC to a base station; Checking whether the frequency band capable of generating IDC is a frequency band set in a network; Receiving measurement and triggering related setting information from the base station regarding the IDC possible frequency band; Performing measurement and IDC triggering based on the verification result and the measurement and triggering related setting information; And transmitting a measurement report message including an IDC indication indicating whether the IDC triggering is performed and a result of the measurement to the base station.

According to another aspect of the present invention, a terminal for controlling in-device coexistence interference (IDC) in a wireless communication system includes a transmission unit for transmitting the terminal capability information including frequency information capable of generating IDC to the base station; A confirmation unit for checking whether the frequency band capable of generating IDC is a frequency band set in a network; A receiver configured to receive, from the base station, measurement and triggering related setting information regarding the IDC possible frequency band; And a measurement and triggering unit configured to perform measurement and IDC triggering based on the confirmation result and setting information related to the measurement and triggering, and the transmission unit includes an IDC instruction indicating whether to perform the IDC triggering and a result of the measurement. The measurement report message is transmitted to the base station.

According to another aspect of the present invention, a method for controlling in-device coexistence interference (IDC) by a base station in a wireless communication system includes the steps of receiving, from a terminal, terminal capability information including frequency information capable of generating IDC; Receiving, by the terminal, a proximity indication message including serving frequency information of a femto cell in proximity from the terminal; Checking whether the IDC frequency band and the serving frequency of the femtocell are a frequency band set in a network; Transmitting measurement and triggering related setting information about the IDC possible frequency band based on the confirmation result to the terminal; And receiving, from the terminal, a measurement report message including an IDC indication and a measurement result regarding the IDC possible frequency.

According to another aspect of the present invention, a base station for controlling in-device coexistence interference (IDC) in a wireless communication system receives the terminal capability information including frequency information capable of generating IDC from the terminal, and the terminal A receiving unit receiving a proximity indication message including serving frequency information of a nearby femto cell from the terminal; A confirmation unit confirming whether the IDC frequency band and the serving frequency of the femtocell are a frequency band set in a network; A transmitter that transmits measurement and triggering related setting information about the IDC generation possible frequency band to the terminal based on the confirmation result, and the reception unit includes an IDC instruction and measurement result regarding the IDC generation possible frequency Receive a measurement report message from the terminal.

According to the present invention, the terminal may instruct the base station to simultaneously perform the information on the co-existence interference in the device and the results of the measurement.

According to the present invention, it is possible to transmit in-device coexistence interference related information through a frequency band not set by the network, and trigger generation of in-device coexistence interference.

According to the present invention, a terminal may instruct in-device coexistence interference related information to a base station.

According to the present invention, it is operable to avoid occurrence of in-device coexistence interference.

1 illustrates a wireless communication system to which an embodiment of the present invention is applied.
2 is an explanatory diagram for explaining in-device coexistence interference.
3 illustrates an example of in-device coexistence interference from an ISM transmitter to an LTE receiver.
4 shows an example in which an ISM band and an LTE band are divided on a frequency band.
5 is an explanatory diagram illustrating an example of mitigating in-device coexistence interference using an FDM scheme according to the present invention.
6 is an explanatory diagram showing another example of mitigating in-device coexistence interference using an FDM scheme according to the present invention.
7 and 8 are explanatory diagrams showing an example of mitigating in-device coexistence interference using a power control scheme according to the present invention.
9 is an explanatory diagram showing an example of mitigating in-device coexistence interference by using a TDM scheme applied to the present invention.
10 shows transmission / reception timings on the time axis of the LTE band and the ISM band which controlled in-device coexistence interference according to the TDM scheme.
11 illustrates another example of mitigating in-device coexistence interference by using a TDM scheme according to the present invention.
12 is a diagram illustrating another example of mitigating in-device coexistence interference using a TDM scheme applied to the present invention.
FIG. 13 is a diagram illustrating another example of mitigating in-device coexistence interference by using a TDM scheme applied to the present invention.
14 illustrates a case in which a terminal receives an interference signal in a device.
15 is a diagram illustrating an example of a proximity indication operation applied to the present invention.
16 shows an example of an IDC generation scenario to which the present invention is applied.
17 is a flowchart illustrating an example of operations of a base station and a terminal that perform in-device coexistence interference control according to the present invention.
18 is a diagram illustrating an example in which a UE performs measurement in consideration of IDC or measurement except IDC according to the present invention.
19 is a flowchart illustrating another example of operations of a base station and a terminal which perform IDC control according to the present invention.
20 is a flowchart illustrating an example of an operation of a terminal that performs in-device coexistence interference control according to the present invention.
21 is a flowchart illustrating an example of an operation of a base station for performing in-device coexistence interference control according to the present invention.
22 is a block diagram illustrating an apparatus for transmitting and receiving information on in-device coexistence interference according to an embodiment of the present invention.

Hereinafter, some embodiments will be described in detail with reference to exemplary drawings. In adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are assigned to the same components as much as possible even though they are shown in different drawings. In the following description of the embodiments of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present disclosure rather unclear.

In describing the components of the present specification, terms such as first, second, A, B, (a), and (b) may be used. These terms are intended to distinguish the constituent elements from other constituent elements, and the terms do not limit the nature, order or order of the constituent elements. If a component is described as being "connected", "coupled" or "connected" to another component, that component may be directly connected or connected to that other component, but there is another component between each component. It will be understood that may be "connected", "coupled" or "connected".

1 illustrates a wireless communication system to which an embodiment of the present invention is applied.

Referring to FIG. 1, a wireless communication system is widely deployed to provide various communication services such as voice and packet data, and includes a user equipment (UE), a base station 20 (evolved NodeB, eNB), and a WLAN access point. (Wireless LAN Access Point: AP, 30), GPS (Global Positioning System, 40) satellite. Herein, the wireless LAN access point (or wireless LAN) is a device supporting IEEE (Institute of Electrical and Electronics Engineers) 802.11 technology, and IEEE 802.11 can be mixed with a WiFi system.

The terminal 10 may be located within the coverage of multiple networks such as cellular networks, wireless LANs, broadcast networks, satellite systems, and the like. The terminal 10 has a plurality of wireless transceivers for accessing various networks and various services regardless of time and place. For example, a smart phone has a Long Term Evolution (LTE), WiFi, Bluetooth (BT) transceiver and a GPS receiver. As such, the design of the terminal 10 is becoming more complex in order to integrate more and more transceivers into one and the same terminal 10 while maintaining good performance. As a result, in-device coexistence interference (IDC interference) is more likely to occur.

Hereinafter, downlink (DL) means communication from the base station 20 to the terminal 10, and uplink (UL) means communication from the terminal 10 to the base station 20. In downlink, the transmitter may be part of the base station 20 and the receiver may be part of the terminal 10. In addition, in uplink, the transmitter may be part of the terminal 10 and the receiver may be part of the base station 20.

The terminal 10 may be fixed or mobile and may be referred to by other terms such as a Mobile Station (MS), a User Terminal (UT), a Subscriber Station (SS), a Mobile Terminal (MT) . The base station 20 is a fixed station that communicates with the terminal 10 and includes a base station (BS), a base transceiver system (BTS), an access point, a femto base station (Femto BS) (relay).

There are no restrictions on multiple access schemes applied to wireless communication systems. (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier-FDMA , OFDM-CDMA, and the like.

2 is an explanatory diagram for explaining in-device coexistence interference.

Referring to FIG. 2, the terminal 10 includes an LTE RF 11, a GPS RF 12, and a Bluetooth / WiFi RF 13. Transmit and receive antennas 14, 15, and 16 are connected to each radio frequency (RF). That is, several kinds of RFs are closely mounted in one device platform. Here, the transmit power of one RF may be much greater than the receive power level to another RF receiver. If the frequency spacing between RFs is not sufficient and the filtering technique is not supported, then a transmission signal of one RF may cause significant interference to a receiver of another RF in the device. For example, "A" of FIG. 2 is an example of a path in which the transmission signal of the LTE RF 11 causes in-device coexistence interference with respect to the GPS RF 12 and the Bluetooth / WiFi RF 23, and the "B". Is an example of a path in which a transmission signal of the Bluetooth / WiFi RF 23 causes in-device coexistence interference with respect to the LTE RF 21.

3 illustrates an example of in-device coexistence interference from an ISM (Industrial, Scientific and Medical) transmitter to an LTE receiver. ISM transmitter refers to a transmitter that transmits in the ISB band, a band that can be freely used without a license in the industrial sciences and medical field.

Referring to FIG. 3, it can be seen that the band of the signal received at the LTE receiver overlaps the band of the transmission signal of the ISM transmitter. In this case, in-device coexistence interference may occur. In particular, when receiving a signal through the LTE receiver in the frequency bands F1 to F3, F2 and F3 indicates that the unacceptable interference occurs in the LTE receiver due to the ISM transmitter. Here, F1 to F3 may be frequency bands belonging to one band. However, F1 exists in a band outside the region affected by In-Device Coexistence (IDC), and F2 and F3 belong to the region affected by IDC. That is, within one band, the degree of coexistence interference problem may vary between frequency bands according to the characteristics of a band filter.

4 shows an example in which an ISM band and an LTE band are divided on a frequency band.

Referring to FIG. 4, band 40, band 7, and band 38 are LTE bands. Band 40 occupies 2300-2400 MHz band in TDD mode, uplink occupies 2500-2570 MHz band in FDD mode, and downlink occupies 2620-2690 MHz in band 7. Band 38 occupies 2570-2620 MHz band in TDD mode. Meanwhile, the ISM band is used as a Wi-Fi channel and a Bluetooth channel and occupies 2400 to 2483.5 MHz. Here, the situation in which coexistence interference occurs in the device is shown in Table 1 below.

Interference band Form of interference Band 40 ISM Tx-> LTE TDD DL Rx Band 40 LTE TDD UL Tx-> ISM Rx Band 7 LTE FDD UL Tx-> ISM Rx Band 7/13/14 LTE FDD UL Tx-> GPS Rx

Referring to Table 1, the notation 'a-b' in the form of interference indicates a situation in which transmitter a causes coexistence interference in a device to receiver b. In band 40, the ISM transmitter causes in-device co-existence interference to the downlink TDD receiver (LTE DL TDD Rx) of the LTE band. A filtering scheme can mitigate some of the coexistence interference in the device, but it is not enough. In addition to the filtering scheme, the application of frequency division multiplex (FDM) scheme can more effectively mitigate in-device coexistence interference.

5 is an explanatory diagram illustrating an example of mitigating in-device coexistence interference using an FDM scheme according to the present invention.

Referring to FIG. 5, the LTE band may be moved in the arrow direction (to the left in the frequency band axis) so that the LTE band does not overlap with the ISM band. This results in handover of the terminal from the ISM band. However, this requires a method in which legacy measurement or new signaling accurately triggers a mobility procedure or radio link failure (RLF) procedure. Alternatively, there may be a method of avoiding a problem in the LTE band with the ISM through filtering or resource allocation. Alternatively, when LTE carrier aggregation is used, overlapping interference may be avoided through a procedure of reconfiguring a set of carriers to be used.

6 is an explanatory diagram showing another example of mitigating in-device coexistence interference using an FDM scheme according to the present invention.

Referring to FIG. 6, the ISM band may be reduced and moved in the direction of the arrow (to the right in the frequency axis) to be separated from the LTE band. In this way, backward compatibility problems may occur. In the case of Bluetooth, the backward compatibility problem may be solved to some extent due to the adaptive frequency hopping mechanism. However, in the case of Wi-Fi, the backward compatibility problem is solved. This can be difficult.

7 and 8 are explanatory diagrams showing an example of mitigating in-device coexistence interference using a power control (PC) scheme according to the present invention.

Referring to FIG. 7, the terminal may lower the transmission power of the LTE signal to a certain level to avoid in-device coexistence interference to improve reception quality of the ISM band. Referring to FIG. 8, the terminal may uniformly transmit the transmission power of the ISM band. By lowering the level, the reception quality of the LTE signal can be improved by avoiding in-device coexistence interference.

9 is an explanatory diagram illustrating an example of mitigating in-device coexistence interference by using a time division multiplexing (TDM) method applied to the present invention.

Referring to FIG. 9, if the reception time of the LTE signal is changed so as not to overlap with the transmission time in the ISM band, in-device coexistence interference may be avoided. For example, if a signal of the ISM band is transmitted at t ₀ , the LTE signal is received at t ₁ .

10 shows transmission / reception timings on the time axis of the LTE band and the ISM band which controlled in-device coexistence interference according to the TDM scheme.

Referring to FIG. 10, it can be seen that in-device coexistence interference can be avoided by the TDM scheme as shown in FIG. 9 without moving between the LTE band and the ISM band.

11 illustrates another example of mitigating in-device coexistence interference by using a TDM scheme according to the present invention.

Referring to FIG. 11, as a TDM scheme based on discontinuous reception (DRX), a pattern periodicity section is a scheduled period section and an unscheduled period section. Splitting can avoid in-device coexistence interference. The UE prevents LTE from transmitting within the unscheduled period to avoid mutual interference between the LTE and the ISM, but the main LTE transmission such as random access or hybrid automatic repeat request (HARQ) retransmission is scheduled. Even within a defined period of time may be allowed. The UE prevents the transmission of the ISM within the scheduled period and allows the transmission of the LTE to avoid mutual interference between the LTE and the ISM. As with the unscheduled period, the main transmission of the ISM band such as Beacon or Wi-Fi may be allowed within the scheduled period. LTE transmission may be prevented to protect the main transmission of the ISM band. In addition, special signaling may be added to protect the main transmission of the ISM band such as a beacon. For example, information on a period of the beacon signaling and a subframe offset may be added. In this case, the subframe offset number and the system frame number may be determined based on "0". The system frame number is one of " 0 " to " 1023 " in units of radio frames in the LTE system. Since one radio frame consists of 10 subframes, the UE can know the exact frame position in the system through the subframe offset number and the system frame number.

12 is a diagram illustrating another example of mitigating in-device coexistence interference using a TDM scheme applied to the present invention. It is a TDM scheme based on HARQ.

Referring to FIG. 12, it is preferable that a retransmission signal is protected when data is transmitted based on HARQ. Here, protecting means that retransmission must be made. If retransmission is not performed to mitigate or avoid in-device coexistence interference by TDM, the performance of the system will be significantly reduced. Based on this, the transmission pattern is determined in consideration of the retransmission period. Subframes 1 and 6 are reserved in advance for DL transmission, and subframes 2 and 7 are reserved for UL transmission. This is called a scheduled subframe. Unscheduled subframes for mitigation of coexistence interference in the device are not used for transmission to protect the ISM band.

Similar to the DRX-based scheme, in the HARQ-based scheme, subframes reserved for transmission may be prevented from being transmitted for important signal transmission in the ISM band. On the contrary, even in an unscheduled subframe, transmission of important messages such as random access, system information, and paging signals may be allowed.

Such a pattern may be given as a bitmap pattern. That is, the number of server frames represented by one bit may be one or more. The period of the pattern is the product of the total length of the bitmap and the number of subframes per bit, and each bit may have a value of 0 if the subframe indicated by the bit is a scheduled subframe and a value of 1 if an unscheduled subframe. . Conversely, if the subframe indicated by each bit is a scheduled subframe, it may have a value of 1 and a non-scheduled subframe.

For example, assume that a period is 20, a pattern representing a subframe is "1001001000", an unscheduled subframe has a value of 0, and the number of subframes represented by one bit is two. In the pattern representing the subframe, since the first, fourth, and seventh bits have a value of 1, it can be seen that the subframes 0, 1, 6, 7, 12, and 13 are scheduled subframes every period.

FIG. 13 is a diagram illustrating another example of mitigating in-device coexistence interference by using a TDM scheme applied to the present invention.

Referring to FIG. 13, as an autonomously denial scheme using a TDM scheme, when in-device coexistence interference occurs, the LTE rejects transmission in order to protect ISM reception. Here, the checkmarked part means that the transmission or reception is approved, and the X marked part means that the transmission or reception is rejected. Even if the UL transmission is granted from the base station, the UE may not perform the UL transmission by rejecting the allocation to protect the ISM reception. Similarly, the ISM may reject the transmission to protect the LTE reception.

Now, in accordance with the present invention, a method of controlling in-device coexistence interference is described. Hereinafter, an operation of reducing, avoiding, or removing interference is collectively referred to as interference control or interference coordination.

Scenarios regarding the on-going IDC state of in-device coexistence interference are shown in Table 2 below.

scenario Justice One In-device coexistence interference in the serving frequency band 2 Potential in-device coexistence interference in the serving frequency band (currently not in-device coexistence interference in progress) 3 In-device coexistence interference in the frequency band other than the serving frequency band 4 Potential in-device co-existence interference in a frequency band other than the serving frequency band (currently not in-device co-existence interference in progress)

Each scenario represents an interference state based on the type of interference and the frequency band. Since the unusable frequency is irrelevant to the serving frequency band, scenario 1 and scenario 3 correspond to in-device coexistence interference.

14 illustrates a case in which a terminal receives an interference signal in a device. It is classified into seven cases based on the frequency of interference and the strength or power.

Referring to FIG. 14, when the seven cases are classified into four patterns based on the frequency of interference, cases 1 and 2 are continuous, cases 3 and 4 are frequent, and cases 5 and Case 6 are sparse, and Case 7 is a pattern of none.

When the seven cases are classified into three patterns based on the intensity of the interference, Case 1, Case 3, and Case 5 are very strong, Case 2, Case 4, and Case 6 are sufficiently weak, Case 7 is a pattern of none.

For example, when it is determined that in-device coexistence interference is in progress, it may be case 1 and case 3. The cases are at least a case where the interference is continuous or frequent and is very strong.

On the other hand, a condition that does not correspond to the in-device co-existence interference is in progress, but the in-device co-existence interference is likely to change to the ongoing state is defined as "in the presence of potential in-device coexistence interference".

For example, the terminal may determine that case 2, case 4, case 5, and case 6 of Table 2 are potential coexistence interference in the device. As another example, the terminal may determine that only case 5 having strong strength exists in the presence of potential in-device coexistence interference. Potential in-device coexistence interference Handover or RRC (Radio Resource Control) setting / resetting, etc. are not impossible in the existing frequency band, the terminal may perform the measurement.

15 is a diagram illustrating an example of a proximity indication operation applied to the present invention. When the terminal detects that the terminal accesses the area of the CSG cell (or HeNB) having the CSG (Closed Subscriber Group) ID belonging to the whitelist of the terminal, the terminal transmits and receives an existing signal. Information of the CSG cell (for example, system information) may be transmitted to a base station, which is called a proximity indication.

Referring to FIG. 15, when a terminal receiving a signal from a first base station eNB in a macro cell 1500 that is a source base station approaches a second base station HeNB in a CSG cell 1510, the terminal accesses the second base station HeNB. Since it is more preferable to receive a signal from a base station, it is required to perform a cell change procedure such as handover.

In order for the UE to perform a more smooth cell change procedure, the UE performs a proximity indication procedure. For example, when the terminal approaches a predetermined area 1520 near the CSG cell, the terminal transmits a proximity indication message to the first base station that is the source base station. Subsequently, the measurement is performed according to the setting of the first base station. If there is no measurement setting for the frequency belonging to the second base station, the measurement is set. The system information (CGI (Cell Global ID), TAI (Tracking Area ID), CSG ID, etc.) received by the terminal from the second base station that is the target base station and the system information (PCI (Physical Cell ID), etc.) held by the terminal Report to the base station, and based on this, a cell change procedure such as handover from the first base station to the second base station is performed.

Due to the proximity indication operation, the first base station does not need to request information (PCI, CGI, TAI, CSG ID, etc.) for CSG cells that are not in proximity. In addition, due to the proximity indication operation, the first base station does not need to configure measurement settings for the cell change in the corresponding CSG cell. That is, the UE will not perform the measurement procedure for cell change to the CSG cell.

Now, an in-device coexistence interference occurrence scenario to which the present invention is applied will be described. When receiving a signal through the LTE receiver in the frequency bands F1 to F3 as shown in FIG. 3, assume that a situation in which unacceptable interference occurs in the LTE receiver due to the ISM transmitter in F2 and F3.

Here, F1 and F2 are frequency bands known by the network, and the network identifies through the deployment or the measurement configuration parameter (MeasConfig) for the establishment of mobility measurement or through EARFCN. Refers to a frequency band set to the terminal. F3 is a frequency band unknown to the network due to the appearance of the femto cell and refers to a frequency band which the network cannot confirm through the deployment and cannot be set by the measurement configuration parameter (MeasConfig) to the terminal.

At this time, the frequency band F3 that is unknown to the network but known to the network by the UE can be a problem with IDC. In this case, the IDC-related measurement is performed by newly performing RRC reconfiguration through a proximity indication operation. You can make a measurement configuration.

16 shows an example of an IDC generation scenario to which the present invention is applied. There are scenarios a through d.

Referring to FIG. 16, in scenario a, the terminal receives a signal through a frequency band F1 where no IDC occurs and a frequency band F2 where an IDC occurs, and is separated from a femtocell in which a service is provided through a frequency band F2 known to a network. (far from)

Scenario b is a case where the terminal receives a signal through the frequency band F1 in which no IDC occurs and the frequency band F2 in which the IDC occurs, and is separated from a femtocell in which a service is provided through a frequency band F3 unknown to the network.

The scenario c is a case where the terminal receives a signal through a frequency band F1 in which no IDC occurs and a frequency band F2 in which the IDC occurs, and is close to a femtocell in which a service is provided through a frequency band F2 known to the network.

Scenario d is a case in which the terminal receives a signal through a frequency band F1 where no IDC occurs and a frequency band F2 where an IDC occurs, and is close to a femtocell in which a service is provided through a frequency band F3 unknown to the network.

According to the present invention, in-device coexistence interference is controlled by distinguishing a process of instructing IDC and setting measurement according to scenarios a to d, respectively. This is because the UE triggers the IDC and transmits the related information to the base station. This is because it is a band (i.e., a frequency band unknown to the network).

Now, according to the present invention, a method for performing an operation for controlling in-device coexistence interference in the terminal and the base station will be described.

17 is a flowchart illustrating an example of operations of a base station and a terminal that perform in-device coexistence interference control according to the present invention. Operations corresponding to the scenario a, scenario b, and scenario c of FIG. 16 are described.

Referring to FIG. 17, the terminal transmits UE capability information to the base station (S1700).

For example, the performance information of the terminal includes information on a frequency band in which IDC may exist, that is, frequency band information that may be an unusable frequency. here. The unusable frequency refers to a frequency in which IDC is ongoing and difficult to perform wireless communication in the corresponding frequency band. For example, although the IDC does not occur at the time of initial LTE access because the WiFi of the terminal is not turned on, the band 40 is a frequency band that is likely to be an unusable frequency due to the IDC process in the terminal with WiFi. It is determined that a frequency band in which IDC may exist. That is, the frequency band in which IDC is likely to exist may include not only the frequency band in which IDC is present but also the frequency band in which potential IDC is present.

As another example, the performance information of the terminal may include only information of the frequency band in which the IDC is in progress, that is, the unusable frequency band.

In this case, the frequency band in which the IDC may exist may be indicated by using an E-UTRA Absolute Radio Frequency Channel Number (EARFCN). Here, EARFCN divides and assigns a number of operable frequency bands of E-UTRA (Evolved-Universal Terrestrial Radio Access).

As an example, the performance information of the terminal may include all EARFCN values of the frequency band in which IDC may exist. As another example, the performance information of the terminal may include an EARFCN corresponding to a boundary value of a frequency band in which IDC may exist. The threshold may be an upper bound or a lower bound, and whether the threshold is the maximum threshold or the minimum threshold is determined in advance through the 3rd Generation Partnership Project (3GPP) LTE standard. In addition, an indicator (boundary type indicator) indicating this may be further included in the performance information of the terminal, or the type of the boundary value may be implicitly determined based on the number of operating bands to which the EARFCN belongs. . As another example, the performance information of the terminal may indicate an operation band unit using EARFCN, and when there are a plurality of operating bands affected by the frequency band indicated by the EARFCN, all of the plurality of operating bands Can be directed.

In addition, despite the execution conditions of the terminal (if there are no potential IDC existing frequency bands, only some bands are affected by IDC interference), the new measurement is applied to all potential IDC existing frequency bands. May not transmit the potential IDC only for a specific frequency band in the performance information of the terminal. That is, only IDC existence can be signaled. However, the measurement of unnecessary potentially problematic frequency bands can lead to waste of power consumption, and thus an optional potential problematic frequency band is preferred.

Subsequently to step S1700, the base station transmits an RRC connection reconfiguration message including information for setting measurement and triggering conditions with respect to a frequency band in which IDC may exist, to perform RRC connection reconfiguration (S1705). The base station transmits configuration information about a candidate frequency of IDC triggering to the terminal.

In the scenario a and scenario c of FIG. 16, the IDC related measurement is set to be performed on the frequency band F2. In the scenario b of FIG. 16, the IDC related measurement is performed to the frequency band F3.

Here, one or more new configuration information elements (config IEs) are required for IDC indication. For example, compared to legacy measurement setup information elements (MeasConfig IE), FDM assist information (disabled frequency bands) and TDM support information (enhanced DRX offset, period) , And on-duration time are further required. Based on legacy measurements, frequency settings can be associated with IDC problems. Accordingly, IDC assistant information may include a measurement result regarding a frequency band usable for FDM IDC solution selection. Since the FDM IDC solution operation is based on handover procedure or cell management, the measurement result is included in the IDC solution decision.

In addition, according to the present invention, an IDC prohibit-timer may be set in the terminal in order to prevent frequent triggering and prevention of interference information caused by IDC that is variably changed. The terminal, which detects the occurrence of in-device coexistence interference and delivers the interference information, does not transmit the interference information to the base station even when the in-device coexistence interference is detected again during the operation of the cutoff timer. This is to prevent the terminal from frequently transmitting interference information caused by coexistence interference in the device, thereby preventing waste of uplink transmission resources due to frequent transmission of interference information by the base station. Accordingly, in the present invention, the terminal may stop (prohibit) the transmission of the IDC indication operation, that is, the IDC indication message, by the blocking timer for a predetermined time. The cutoff timer is controlled by the network, and the length of the cutoff timer may be set through the RRC connection reconfiguration message.

In addition, when the base station wants to limit IDC triggering, it may be set through the RRC connection reconfiguration message.

Subsequently to step S1705, when the terminal approaches the area of the femtocell in which the service is provided at a frequency F2 known to the network, as shown in scenario c of FIG. 16, the terminal may optionally perform a self organization network (SON) operation. A proximity indication message may be transmitted to the base station to perform a proximity indication operation (S1706). Unlike scenario a of FIG. 16, in scenario c, the UE is in close proximity to the femtocell. In the proximity indication message, the master frequency band information (entering F2) for F2 may be included.

However, since the proximity indication operation is an optional procedure as a terminal execution issue, the terminal may or may not perform the proximity indication operation by determining itself. However, if the frequency band F2 is a frequency band included in the CSG cell list, and a terminal for receiving information such as a CSG ID, the proximity indication message must be transmitted.

Meanwhile, in the scenario a or scenario b of FIG. 16, since the distance between the terminal and the femtocell is far, there is no need to consider mobility, and the proximity indication operation is also unnecessary. Especially for scenario b, proximity indication operation is unnecessary even though the network is not aware of the femtocell's serving frequency F3.

Subsequently to step S1705 (or S1706), the terminal performs measurement on a frequency band in which IDC may be present, that is, a frequency band recognized by the network, and performs IDC triggering based on the IDC triggering condition (S1710). ). The measurement may be performed to obtain a measurement result to be transmitted to the base station, and may indicate IDC through IDC triggering. The measurement and the IDC triggering may be performed simultaneously, the measurement may be performed before the IDC triggering, or the IDC triggering may be performed before the measurement.

IDC triggering is triggered according to the implementation of the terminal or a triggering condition set by the base station. The triggering condition may be set based on a test case, IDC interference intensity and activity, a packet error rate, or a measurement result. Here, the activity of IDC refers to an indicator of how often IDC occurs in time. For example, it may be defined as a ratio of a subframe in which IDC does not occur and a subframe in which IDC occurs. For example, there is a method of obtaining an average value based on each subframe weight.

In scenarios a and c of FIG. 16, IDC related measurements are performed for frequency band F2.

Here, in the scenario c of FIG. 16, the frequency band information for the F2 configured by the existing S1705 without having to perform a separate RRC connection reconfiguration in the proximity indication message transmitted from the terminal in step S1706 is entered. The measurement of S1710 is performed using F2), and IDC triggering is performed based on the IDC triggering condition. Meanwhile, in the scenario b of FIG. 16, the terminal performs IDC related measurement on the frequency band F3. Since the distance between the terminal and the femtocell is far, the terminal does not need to consider mobility and transmits it to the base station through a proximity indication message. It just doesn't.

Existing measurement or UE internal coordination is changed to a new measurement. The measurement may be a separate measurement performed separately or together with IDC interference by appropriate terminal internal coordination. The measurement can detect the impact of IDC on the communication quality (communication quality) of the LTE reception side or ISM reception side.

The basic intention of the measurement is to prevent mis-handling of mobility due to the effects of IDC interference. For mobility purposes, measurements can be performed without the impact of IDC interference. The influence of IDC interference is extracted or subtracted from the measurement results.

18 is a diagram illustrating an example in which a UE performs measurement in consideration of IDC or measurement except IDC according to the present invention.

Referring to FIG. 18, the terminal obtains a measurement sample with the direction of IDC in a section (first section) in which IDC occurs in a serving cell or neighbor cell in which IDC occurs, and the section in which IDC does not occur ( In the second section), a measurement sample without the influence of IDC is obtained. Here, the neighbor cell refers to a cell that is set through the RRC connection resetting process and used as a comparison group of measurement report events. In addition, the terminal obtains a measurement sample in the entire period (third section) irrespective of the IDC in the serving cell or the neighbor cell in which IDC does not occur. In this case, the UE may obtain a measurement sample in every subframe, a predetermined subframe, or any subframe in each interval.

For example, a measurement sample having an influence of IDC in the first interval may include IDC, inter-cell interference (eg, interference of co-channel serving and non-serving cells). Measurement samples that take into account both the effects of interference that combines adjacent channel interference, etc.) and thermal noise, and the measurement samples without the influence of IDC in the second interval are the effects of inter-cell interference or thermal noise. Only the measurement sample.

In another embodiment, in order to remove the influence of interference caused by IDC from the measurement sample in the serving cell or the neighboring cell in which the IDC occurs, the transmission of the ISM may be prevented for the measurement sample. . Preventing the transmission of ISM may be a way to reduce the transmission power of the ISM to a fairly small level. The considerably small level is an example where the IDC interference strength of the ISM is as small as -20 dB compared to the LTE received signal at the LTE receiver. As another example of preventing the transmission of the ISM, the ISM transmission may be suspended or not transmitted for the sample. That is, although the transmission of the ISM is planned, the transmission may be suspended in time or the transmission may be rejected by the terminal. According to this method, it is possible to obtain a measurement sample in which the influence of in-device coexistence interference is eliminated in all sections in FIG. 18. Of course, a measurement sample without the influence of IDC means a measurement sample with only the influence of intercell interference or thermal noise.

In another embodiment, two measurement samples may be obtained for a first section in a serving cell or a neighbor cell in which IDC occurs. The two measurement samples mean a measurement sample including the influence of IDC interference and a measurement sample without the influence of IDC interference. The measurement sample from which the influence of IDC interference is removed means a measurement sample having a measurement value having no influence of interference by applying an interference cancellation technique to the sample. An embodiment of the interference cancellation scheme may be a method of compensating the strength of the ISM transmit power at the ISM transmitter by the SINR value of the sample.

Here, the first network system refers to a network system that provides the effect of interference when IDC occurs. The network system attacked by the interference may be referred to as a second network system. For example, when the ISM receiver is interfered with by LTE uplink, the ISM is the second network system. On the contrary, when the ISM transmitter receives interference from the LTE downlink receiver, the LTE system is the second network system.

The measurement sample without the influence of IDC in the serving cell or neighbor cell obtained based on RSRQ is conceptually represented by Equation 1 below.

Where S is the strength of the received signal through the neighbor cell in the second network system, I is the strength of the interference signal (e.g., inter-cell interference) acting on the second network system, and N is noise (e.g., , Thermal noise). In other words, the measurement sample refers to a relative ratio of interference and noise of the received signal.

The measurement sample without the influence of IDC in the serving cell or neighbor cell obtained based on RSRP is conceptually shown in Equation 2 below.

Here, S denotes the strength of the received signal through the neighbor cell in the second network system. That is, the measurement sample refers to the strength of the received signal in the corresponding neighbor cell in the second network system.

A measurement sample having an influence of IDC in a serving cell or a neighbor cell obtained based on RSRQ is conceptually expressed by Equation 3 below.

Where S is the strength of the received signal through the serving cell in the second network system, I is the strength of the interference signal (e.g., inter-cell interference) acting on the second network system, and N is noise (e.g., , Thermal noise), and I 'is the strength of IDC. That is, the measurement sample refers to the relative ratio of the IDC and inter-cell interference of the received signal.

The measurement sample with the influence of IDC in the serving cell or neighbor cell obtained on the basis of RSRP is conceptually expressed as Equation 4 below.

Here, I 'is the strength of the IDC, and the measurement sample means the strength of the IDC signal in the serving cell. S is the strength of the received signal in the second network system. If you only want to measure the impact of IDC, I 'will be the result. If the mixed IDC is measured, S + I 'will be the result. If the value without IDC is measured, S will be the result.

Meanwhile, the entity performing the measurement (eg, the terminal) may be one entity, and the entity performing the measurement may be plural. For example, an entity performing a measurement considering IDC and an entity performing a measurement not considering IDC may exist independently.

Here, the measurement result refers to a value finally calculated by filtering the measurement samples. For example, in case of LTE, the final RSRP (Reference Signal Received Power) and RSRQ (Reference Signal Received Quality) values generated through L1 filtering and L3 filtering are reported to the base station. However, the measurement result considering IDC may be a result of filtering only the measurement samples including IDC, or may be a result of filtering both the measurement samples including IDC and the measurement samples without IDC. In addition, the IDC-removed measurement result is a result of filtering only measurement samples that do not include IDC, or IDC is determined by interference cancellation in measurement samples containing IDC together with measurement samples that do not include IDC. It may be the result of filtering the removed measurement samples.

For example, the measurement result may be a measurement result from which IDC is removed. As another example, the measurement result may be a measurement result considering IDC. As another example, the measurement result may include both a measurement result with IDC removed and a measurement result considering IDC. As another example, the measurement result may include both the strength of IDC and the measurement result from which IDC is removed. As another example, the measurement result may include both the strength of the IDC and the measurement result in consideration of the IDC. As another example, the measurement result may include all of the strength of IDC, activity of IDC, and measurement result from which IDC is removed. As another example, the measurement result may include all of the measurement results in consideration of the strength of the IDC, the activity of the IDC, and the IDC.

Subsequently to step S1710, the UE transmits IDC indication information (also referred to as IDC assistant information) and a measurement result to the base station (S1715).

The IDC indication information (or IDC assistance information) is distinguished support information or integrated support information for each of the TDM operation and the FDM operation. In this case, the differentiated support information for each of the TDM operation and the FDM operation requires priority between the TDM operation and the FDM operation, which is an IDC solution, from the terminal side. Measurement results may be included in the IDC assistance information. Can be used to determine which IDC solution is more appropriate. For example, if the channel quality of the target cell for the FDM operation is poor, the base station may select a TDM solution to solve the IDC problem of the serving cell.

For example, the IDC indication information and the measurement result may be transmitted to the base station through an IDC indication message, which is a new message format.

At this time, the IDC indication message may include the unusable frequency band information. For example, the IDC indication message may include all EARFCN values in the frequency band in which IDC may exist. As another example, the IDC indication message may include an EARFCN corresponding to a boundary value of a frequency band in which IDC may exist. The boundary value may be a maximum boundary value or a minimum boundary value. As another example, the IDC indication message may include an EARFCN corresponding to the minimum threshold, and may indicate that a frequency band larger than the minimum threshold is an unusable frequency. Alternatively, the IDC indication message may include an EARFCN corresponding to the maximum boundary value, and may indicate that a frequency band smaller than the maximum boundary value is an unusable frequency. In this case, whether the EARFCN included in the IDC indication message is the maximum boundary value or the minimum boundary value may be determined in advance through the 3GPP LTE standard. Alternatively, an indicator (boundary type indicator) indicating whether the EARFCN is the maximum boundary value or the minimum boundary value may be further included in the IDC indication message. As another example, the type of the boundary value may be implicitly determined based on the number of operating bands to which the EARFCN included in the IDC indication message belongs. As another example, the IDC indication message may include an EARFCN, and the EARFCN may indicate that the operating band region itself in which the EARFCN is located is an unusable frequency band. As another example, when there are a plurality of operating bands affected by the frequency band indicated by the EARFCN, the IDC indication message may be set to indicate that all of the plurality of operating bands are unavailable frequency bands.

If the IDC entry indicator indicating that the IDC in progress is started is not transmitted separately, if the frequency band that has been recognized as an available frequency band is signaled to the base station by the IDC indication message, the base station It may be determined that the IDC in progress state has started for the corresponding frequency band.

In addition, the IDC indication message may include TDM pattern information. The TDM pattern may be a DRX period, a DRX activity interval, or a DRX subframe offset value.

In addition, the IDC indication message may include a measurement result of performing measurement in consideration of IDC or measurement in which IDC is removed according to a rule in which a terminal acquires a measurement sample.

As another example, the IDC indication information and the measurement result may be transmitted to the base station through a measurement report message. The measurement report message may include not only measurement results but also unusable frequency information or TDM pattern information.

For example, the measurement report message may include all EARFCN values in the frequency band in which IDC may exist. As another example, the measurement report message may include an EARFCN corresponding to a boundary value of a frequency band in which IDC may exist. The boundary value may be a maximum boundary value or a minimum boundary value. As another example, the measurement report message may include an EARFCN corresponding to the minimum threshold, and may indicate that a frequency band larger than the minimum threshold is an unusable frequency. Alternatively, the measurement report message may include an EARFCN corresponding to the maximum boundary value, and may indicate that a frequency band smaller than the maximum boundary value is an unusable frequency based on this. In this case, whether the EARFCN included in the measurement report message is the maximum boundary value or the minimum boundary value may be determined in advance through the 3GPP LTE standard. Alternatively, an indicator (boundary type indicator) indicating whether the EARFCN is the maximum boundary value or the minimum boundary value may be further included in the measurement report message. Alternatively, the type of the boundary value may be implicitly determined based on the number of operating bands to which the EARFCN included in the measurement report message belongs. As another example, the measurement report message may include an EARFCN, and the EARFCN may be set to indicate that the operating band region itself in which the EARFCN is located is an unusable frequency band. As another example, when there are a plurality of operating bands affected by the frequency band indicated by the EARFCN, the measurement report message may be set to indicate that all of the plurality of operating bands are unavailable frequency bands.

If the IDC access indicator indicating that the IDC in progress is started is not transmitted separately, if the frequency band that has been recognized as an available frequency band to the base station is signaled as an unusable frequency band through the measurement report message, the base station determines that frequency. It can be determined that the IDC ongoing state for the band has started.

Meanwhile, the measurement report message may include TDM pattern information. The TDM pattern may be a DRX period, a DRX activity interval, or a DRX subframe offset value.

The unusable frequency information and the TDM pattern information included in the measurement report message may be one or plural. However, when there are a plurality, the unusable frequency information and the TDM pattern information are paired and signaled.

In addition, the measurement report message may include a measurement result of performing the measurement in accordance with the rule that the terminal obtains a measurement sample. In this case, the terminal may perform measurement in consideration of IDC or measurement in which IDC is removed. For example, the measurement result included in the measurement report message may be a measurement result from which IDC is removed. As another example, the measurement result included in the measurement report message may be a measurement result considering IDC. As another example, the measurement result included in the measurement report message may include both the measurement result with IDC removed and the measurement result considering IDC. As another example, the measurement result included in the measurement report message may include both the strength of the IDC and the measurement result from which the IDC has been removed. As another example, the measurement result included in the measurement report message may include both the strength of the IDC and the measurement result in consideration of the IDC. As another example, the measurement result included in the measurement report message may include all of the intensity of the IDC, the activity of the IDC, and the measurement result from which the IDC has been removed. As another example, the measurement result included in the measurement report message may include all of the measurement results in consideration of the strength of the IDC, the activity of the IDC, and the IDC.

Following step S1715, the base station selects the most appropriate IDC solution based on the IDC indication information and the measurement result received from the terminal (S1720). At this time, the IDC solution may be an FDM operation or a TDM operation. The FDM operation or the TDM operation may be an operation according to FIGS. 5 to 13. For example, when a problem occurs in a frequency band provided by a base station, if the frequency band available according to the IDC indication information does not cause a problem due to load balancing and does not significantly affect handover (for example, For example, when the RSRP or RSRQ value of the corresponding frequency band is sufficiently large), the FDM operation may be performed. Otherwise, the TDM operation may be performed in the serving cell.

In step S1720, the base station transmits an IDC solution to the terminal to perform an IDC solution (S1725). For example, the IDC solution may be transmitted through an RRC connection reset message.

For example, the IDC resolution operation may include an operation of a blocking timer for prohibiting transmission of an IDC indication message (or a measurement report message) for a predetermined time.

As another example, when the determined IDC solution is an FDM operation, a secondary serving cell is changed through a serving cell management operation (for example, deletion of a secondary serving cell in question). A handover procedure for changing the primary serving cell may be initiated.

As another example, when the determined IDC solution is a TDM operation, a specific DRX pattern may be transmitted through an RRC connection reconfiguration message.

As another example, when the determined IDC solution is a TDM operation, an indicator indicating that the DRX pattern is caused by IDC may be transmitted together with a specific DRX pattern through an RRC connection reconfiguration message. The measurement performed by the terminal according to the indication of the indicator may be changed differently than before.

As another example, when the determined IDC solution is a TDM operation, HARQ retransmission in the LTE band may be rejected for handling of a beacon when transmitting a signal in the ISM band. That is, the start of the IDC solution may be instructed through an IDC indication message (or a measurement report message).

On the other hand, if the IDC solution determined by the base station based on IDC indication information is the same as the existing IDC solution, the IDC solution transmission process may be omitted.

19 is a flowchart illustrating another example of operations of a base station and a terminal which perform IDC control according to the present invention. This operation corresponds to scenario d of FIG. 16.

Referring to FIG. 19, the terminal transmits performance information of the terminal to the base station (S1900).

For example, the performance information of the terminal includes information on a frequency band in which IDC may exist, that is, frequency band information that may be an unusable frequency. As another example, the performance information of the terminal may include only information of the frequency band in which the IDC is in progress, that is, the unusable frequency band.

In this case, the frequency band in which the IDC may exist may be indicated using EARFCN. As an example, the performance information of the terminal may include all EARFCN values of the frequency band in which IDC may exist. As another example, the performance information of the terminal may include an EARFCN corresponding to a boundary value of a frequency band in which IDC may exist. The boundary value may be a maximum boundary value or a minimum boundary value, and whether the boundary value is the maximum boundary value or the minimum boundary value is determined in advance through 3GPP LTE standard, or an indicator (boundary type indicator) indicating this is determined by the terminal. The type of the boundary value may be implicitly determined based on the number of operating bands to which the EARFCN belongs or is further included in the performance information. As another example, the performance information of the terminal may indicate an operation band unit using EARFCN, and when there are a plurality of operating bands affected by the frequency band indicated by the EARFCN, all of the plurality of operating bands Can be directed.

In addition, despite the execution conditions of the terminal (if there are no potential IDC existing frequency bands, only some bands are affected by IDC interference), the new measurement is applied to all potential IDC existing frequency bands. May not exist whether or not there is a potential IDC for a specific frequency band in the performance information of the terminal. That is, only IDC existence can be signaled. However, the measurement of unnecessary potentially problematic frequency bands can lead to waste of power consumption, and thus an optional potential problematic frequency band is preferred.

Subsequently to step S1900, the base station transmits an RRC connection reconfiguration message including information for setting measurement and triggering conditions with respect to a frequency band in which IDC may exist, to perform an RRC connection reconfiguration (S1905). The base station transmits configuration information about a candidate frequency of IDC triggering to the terminal.

In the scenario d of FIG. 16, an IDC related measurement is set for the frequency band F2. Here, one or more new configuration information elements (config IEs) are required for IDC indication. For example, compared to legacy measurement setup information elements (MeasConfig IE), more FDM assist information (disabled frequency bands) and TDM support (enhanced DRX offset, periodicity, and on-duration time) are required. do. Based on legacy measurements, frequency settings can be associated with IDC problems. Accordingly, IDC assistant information may include a measurement result regarding a frequency band usable for FDM IDC solution selection. Since the FDM IDC solution operation is based on handover procedure or cell management, the measurement result is included in the IDC solution decision. In addition, a cutoff timer (IDC prohibit-timer) may be set, and the length of the cutoff timer may be set through the RRC connection reestablishment message.

In addition, when the base station wants to limit IDC triggering, it may be set through the RRC connection reconfiguration message.

After step S1905, the terminal transmits a proximity indication message to the base station to perform a proximity indication operation (S1910). When it is detected that the UE approaches the area of the CSG cell, the proximity indication operation is performed. In particular, in the scenario d of FIG. 16, since the frequency band F3 provided with the service in the femto cell is a frequency band not set in the network and a frequency band unknown in the network, the terminal is configured to the frequency band F3. Transmit information about to the base station. As such, it is advantageous for the terminal to enter the femto cell as quickly as possible through the proximity indication operation to efficiently receive the service.

Subsequently to step S1910, the base station transmits an RRC connection reconfiguration message including information for setting measurement and triggering conditions for the frequency band F3 to the terminal, and performs RRC connection reconfiguration (S1915). The setting of the measurement and triggering conditions for the frequency band F2, which was set in the previous step (S1905), remains unchanged, and the measurement and triggering conditions for the frequency band F3 are further reset.

Subsequently to step S1915, the terminal performs measurement on a frequency band in which IDC may exist, and performs IDC triggering based on the IDC triggering condition (S1920). The measurement may be performed to obtain a measurement result to be transmitted to the base station, and may indicate IDC through IDC triggering. The measurement and the IDC triggering may be performed simultaneously, the measurement may be performed before the IDC triggering, or the IDC triggering may be performed before the measurement.

IDC triggering is triggered according to triggering conditions set by the execution of the terminal or the base station. The triggering condition may be set based on a test case, IDC interference intensity and activity, PER, or measurement result.

In the scenario d of FIG. 16, the IDC related measurement is performed on the frequency band F2 in the steps S1905 to S1915 of FIG. 19. Subsequently, IDC related measurements are performed on the frequency bands F2 and F3 after step S1915 of FIG. 19.

Existing measurement or terminal internal adjustment is changed to a new measurement. The measurement may be a distinct measurement performed separately or with IDC interference by appropriate terminal internal coordination. The measurement can detect the IDC influence on the communication quality of the LTE reception side or the ISM reception side.

The basic purpose of the measurement is to prevent mishandling of mobility due to the influence of IDC interference. For mobility purposes, measurements can be performed without the impact of IDC interference. Extract or remove the effects of IDC interference from the measurement results.

The UE may perform measurement in consideration of IDC or measurement other than IDC as shown in FIG. 18, and the measurement result may be a measurement result from which IDC has been removed. As another example, the measurement result may be a measurement result considering IDC. As another example, the measurement result may include both a measurement result with IDC removed and a measurement result considering IDC. As another example, the measurement result may include both the strength of IDC and the measurement result from which IDC is removed. As another example, the measurement result may include both the strength of the IDC and the measurement result in consideration of the IDC. As another example, the measurement result may include all of the strength of IDC, activity of IDC, and measurement result from which IDC is removed. The activity of IDC refers to an indicator of how often IDC occurs in time. For example, the IDC may be defined as a ratio of a subframe in which IDC does not occur and a subframe in which IDC occurs. There is a method of obtaining an average value based on subframe weights. As another example, the measurement result may include all of the measurement results in consideration of the strength of the IDC, the activity of the IDC, and the IDC.

Following step S1920, the terminal transmits IDC indication information (or IDC assistance information) and a measurement result to the base station (S1925).

The IDC indication information (or IDC assistance information) may be distinguished support information or integrated support information for each of the TDM operation and the FDM operation.

 For example, the IDC indication information and the measurement result may be transmitted to the base station through an IDC indication message, which is a new message format. At this time, the IDC indication message may include the unusable frequency band information.

At this time, if the IDC access indicator indicating that the IDC in progress is started is not transmitted separately, if the frequency band that is recognized as the usable frequency band to the base station through the IDC indication message is signaled as an unusable frequency band, the base station is It may be determined that the IDC in progress state has started for the corresponding frequency band.

At this time, the IDC indication message may include TDM pattern information. The TDM pattern may be a DRX period, a DRX activity interval, or a DRX subframe offset value.

In this case, the IDC indication message may include a measurement result of performing measurement in consideration of IDC or measurement in which IDC is removed according to a rule in which the UE acquires a measurement sample.

As another example, the IDC indication information and the measurement result may be transmitted to the base station through a measurement report message. The measurement report message may include not only measurement results but also unusable frequency information or TDM pattern information.

In this case, when the IDC entry indicator indicating that the IDC in progress is started is not separately transmitted, when the frequency band that is recognized as the usable frequency band is signaled to the unusable frequency band through the measurement report message, the base station corresponds to the corresponding frequency band. It can be determined that the IDC in progress state has started for the frequency band.

In this case, the measurement report message may include TDM pattern information. The TDM pattern may be a DRX period, a DRX activity interval, or a DRX subframe offset value.

In this case, the unusable frequency information and the TDM pattern information included in the measurement report message may be one or plural. However, when there are a plurality, the unusable frequency information and the TDM pattern information are paired and signaled.

In addition, the measurement report message may include a measurement result of performing the measurement in accordance with the rule that the terminal obtains a measurement sample. In this case, the terminal may perform measurement in consideration of IDC or measurement in which IDC is removed.

Following step S1925, the base station selects the most appropriate IDC solution based on the IDC indication information and the measurement result received from the terminal (S1930). At this time, the IDC solution may be an FDM operation or a TDM operation. The FDM operation or the TDM operation may be an operation according to FIGS. 5 to 13. For example, when a problem occurs in a frequency band provided by a base station, if the frequency band available according to the IDC indication information does not cause a problem due to load balancing and does not significantly affect handover (for example, For example, when the RSRP or RSRQ value of the corresponding frequency band is sufficiently large), the FDM operation may be performed. Otherwise, the TDM operation may be performed in the serving cell.

After step S1930, the base station transmits an IDC solution to the terminal to perform the IDC solution (S1935). For example, the IDC solution may be transmitted through an RRC connection reset message.

For example, the IDC resolution operation may include an operation of a blocking timer for prohibiting transmission of an IDC indication message (or a measurement report message) for a predetermined time.

As another example, when the determined IDC solution is an FDM operation, a secondary serving cell is changed through a serving cell management operation (for example, deletion of a secondary serving cell in question). A handover procedure for changing the primary serving cell may be initiated.

As another example, when the determined IDC solution is a TDM operation, a specific DRX pattern may be transmitted through an RRC connection reconfiguration message.

As another example, when the determined IDC solution is a TDM operation, an indicator indicating that the DRX pattern is caused by IDC may be transmitted together with a specific DRX pattern through an RRC connection reconfiguration message. The measurement performed by the terminal according to the indication of the indicator may be changed differently than before.

As another example, when the determined IDC solution is a TDM operation, HARQ retransmission in the LTE band may be rejected for handling of beacons while transmitting a signal in the ISM band. That is, the start of the IDC solution may be instructed through an IDC indication message (or a measurement report message).

On the other hand, if the IDC solution determined by the base station based on IDC indication information is the same as the existing IDC solution, the IDC solution transmission process may be omitted.

20 is a flowchart illustrating an example of an operation of a terminal that performs in-device coexistence interference control according to the present invention.

Referring to FIG. 20, the terminal transmits frequency information in which IDC may exist to the base station (S2000). Frequency information that the IDC may exist may be transmitted through the performance information of the terminal. In addition to the frequency band in which IDC is in progress, information about a frequency band in which IDC may be present may be indicated. The frequency information of the possibility of the IDC may be indicated using EARFCN. For example, all EARFCN values of frequency bands in which IDC may exist may be included, or EARFCNs corresponding to boundary values of frequency bands in which IDC may exist.

The base station may transmit information for setting IDC related measurement and triggering to the terminal based on the frequency information.

The terminal checks whether the frequency band in which IDC may exist (or the frequency band in which IDC exists) is a frequency band set by the network (S2005). When the frequency band is set by the network, the proximity indication message can be selectively transmitted to the base station when the terminal approaches the femtocell provided with the service through the frequency band. At this time, the terminal does not receive information from the base station to configure the measurement and triggering for the frequency band. However, when the UE is away from the femtocell provided with the service through the frequency band, the proximity indication operation is not performed.

On the other hand, if the frequency band is not set by the network, if the terminal is close to the femtocell that the service is provided through the frequency band, because the terminal necessarily needs information of the frequency band in the network, the terminal is a base station to the frequency band Information should be sent. The base station transmits information additionally configured to perform measurement and triggering on the frequency band to the terminal. However, when the UE is away from the femtocell provided with the service through the frequency band, the proximity indication operation is not performed.

The UE performs measurement and triggering not only for the frequency band F2 based on the proximity indication operation but also for the frequency band F3 when necessary (for example, when the serving frequency of the femtocell is F3 and the UE is close to the femtocell). The IDC indication information and the measurement result are transmitted to the base station (S2010).

If the frequency band is set by the network, when the terminal approaches a femtocell provided with a service through the frequency band, the proximity indication message is selectively transmitted to the base station, so that the terminal does not transmit the proximity indication message. No problem with taking measurements and triggering. In addition, the terminal does not receive measurement and triggering setting information regarding the frequency band from the base station.

Accordingly, measurement and triggering are performed based on the existing measurement and triggering setting information regardless of the proximity indication operation, and the IDC indication information and the measurement result are transmitted to the base station.

On the other hand, when the frequency band is not set by the network, if the terminal is near to the femto cell that the service is provided through the frequency band (near), the terminal is measured and received from the base station in response to the proximity indication operation and Measurement and triggering are performed based on the triggering setting information, and the IDC indication information and the measurement result are transmitted to the base station.

In other words, after transmitting the capability information to the base station, the terminal receives an RRC connection reconfiguration message from the base station. IDC measurement and reporting may be performed on the frequency band in the received RRC connection reconfiguration message.

Here, the terminal may check the information on the frequency band in the RRC connection reconfiguration message received from the base station to transmit a selective proximity indication message. For example, a frequency band into which the terminal enters does not exist in an RRC connection reconfiguration message received after transmitting the performance information to a base station, that is, a frequency band not set by the base station. ), The terminal may transmit the proximity indication message including information on the identified unset frequency band to the base station. Thereafter, the base station further receives an RRC connection reconfiguration message including the unknown frequency band from the base station, performs measurement on IDC, and provides information and IDC indicating that IDC is generated. Transmit the measurement result to the base station.

Meanwhile, as another example, a frequency band in which the terminal enters is a frequency band in an RRC connection reconfiguration message received after transmitting performance information of the terminal to a base station, that is, a frequency band set by the base station. network), the terminal does not need to receive the RRC connection reconfiguration message from the base station again. That is, the IDC is measured by using the previously received RRC connection reconfiguration message to transmit information indicating that IDC is generated and the measurement result by IDC to the base station. As a result, the proximity indication message may not be transmitted by the terminal to the base station. In this case, the terminal may selectively transmit the proximity indication message. Here, in the case of entry into a frequency band known by the base station, the base station does not need to perform additional RRC connection reconfiguration for the frequency band entered by the terminal.

21 is a flowchart illustrating an example of an operation of a base station for performing in-device coexistence interference control according to the present invention.

Referring to FIG. 21, the base station sets IDC related measurement and triggering to the terminal based on whether the proximity indication message is received from the terminal and whether the proximity indication message includes information on a frequency band not set by the network. The information is transmitted (S2100).

If the base station has not received the proximity indication message, it is to set the measurement and triggering based on the frequency band information of the IDC presence.

If the base station has received the proximity indication message but includes information on the frequency band set by the network, the base station sets the measurement and triggering based on the frequency band information of the IDC possibility, and does not transmit an additional RRC connection reconfiguration message.

If the base station receives the proximity indication message, and includes information about the frequency band not set by the network, the terminal receives a new RRC connection reestablishment message configured to perform measurement and triggering on the frequency band not set by the network. Send to.

The base station receives the IDC indication information and the measurement result (S2105), selects an IDC solution based on this, and transmits it to the terminal (S2110). At this time, the IDC solution may be an FDM operation or a TDM operation. The FDM operation or the TDM operation may be an operation according to FIGS. 5 to 13. For example, when a problem occurs in a frequency band provided by a base station, if the frequency band available according to the IDC indication information does not cause a problem due to load balancing and does not significantly affect handover (for example, For example, when the RSRP or RSRQ value of the corresponding frequency band is sufficiently large), the FDM operation may be performed. Otherwise, the TDM operation may be performed in the serving cell.

In addition, the IDC solution may be transmitted through the RRC connection reconfiguration message. For example, the IDC resolution operation may include an operation of a blocking timer for prohibiting transmission of an IDC indication message (or a measurement report message) for a predetermined time. As another example, when the determined IDC solution is an FDM operation, a secondary serving cell is changed through a serving cell management operation (for example, deletion of a secondary serving cell in question). A handover procedure for changing the primary serving cell may be initiated. As another example, when the determined IDC solution is a TDM operation, a specific DRX pattern may be transmitted through an RRC connection reconfiguration message. As another example, when the determined IDC solution is a TDM operation, an indicator indicating that the DRX pattern is caused by IDC may be transmitted together with a specific DRX pattern through an RRC connection reconfiguration message. The measurement performed by the terminal according to the indication of the indicator may be changed differently than before. As another example, when the determined IDC solution is a TDM operation, HARQ retransmission in the LTE band may be rejected for handling of beacons while transmitting a signal in the ISM band. That is, the start of the IDC solution may be instructed through an IDC indication message (or a measurement report message).

On the other hand, if the IDC solution determined by the base station based on IDC indication information is the same as the existing IDC solution, the IDC solution transmission process may be omitted.

22 is a block diagram illustrating an apparatus for transmitting and receiving information on in-device coexistence interference according to an embodiment of the present invention.

Referring to FIG. 22, the terminal 2200 includes a receiver 2205, a confirmation unit 2210, a measurement and triggering unit 2215, and a transmitter 2220.

The transmitter 2215 transmits frequency information that may exist in IDC to the base station 2250. Frequency information that the IDC may exist may be transmitted through the performance information of the terminal. In addition to the frequency band in which IDC is in progress, information about a frequency band in which IDC may be present may be transmitted. The frequency information of the possibility of the IDC may be indicated using EARFCN. For example, all EARFCN values of frequency bands in which IDC may exist may be included, or EARFCNs corresponding to boundary values of frequency bands in which IDC may exist.

The receiver 2205 may receive information for setting IDC related measurement and triggering from the base station 2250 and may receive the information through an RRC connection reconfiguration message.

The identification unit 2210 confirms whether the frequency band in which the IDC can exist or the frequency band in which the IDC is present is a frequency band set by the network. When the frequency band is set by the network and the terminal 2200 approaches the femtocell provided with the service through the frequency band, the transmitter 2220 may selectively transmit the proximity indication message to the base station 2250. have. At this time, the terminal does not receive information from the base station to configure the measurement and triggering for the frequency band. However, when the UE is away from the femtocell provided with the service through the frequency band, the proximity indication operation is not performed.

If the identification unit 2210 confirms that the frequency band is not set by the network, if the terminal 2200 is close to the femtocell in which the service is provided through the frequency band, the information of the frequency band is necessarily required in the network. Therefore, the transmitter 2220 transmits the frequency band information to the base station 2250.

The receiver 2205 receives, from the base station 2250, information that is set to perform measurement and triggering on the frequency band. However, when the terminal 2200 is separated from the femto cell in which the service is provided through the frequency band, the proximity indication operation is not performed.

The measurement and triggering unit 2215 performs measurement and triggering based on the measurement and triggering related setting information based on the check result and the proximity indication operation.

If the frequency band is set by the network, the proximity indication message is selectively transmitted to the base station 2250 when the UE approaches the femtocell provided with the service through the frequency band, so that the proximity indication message is not transmitted. Even if the terminal 2200 does not have a problem in performing the measurement and triggering. In this case, the receiver 2205 does not receive measurement and triggering setting information regarding the frequency band from the base station. Accordingly, the measurement and triggering unit 2215 performs measurement and triggering based on the existing measurement and triggering setting information regardless of the proximity indication operation.

If the frequency band is not set by the network, the measurement and triggering unit 2215 responds to the proximity indication operation if the terminal 2200 is near to the femtocell provided with the service through the frequency band. As described above, measurement and triggering are performed based on the measurement and triggering setting information received from the base station 2250.

The transmitter 2220 transmits the IDC indication information and the measurement result, which are the result of the measurement and the triggering, to the base station 2250 and may transmit the measurement report message.

The base station 2250 includes a receiver 2255, a confirmer 2260, an IDC resolution selector 2265, and a transmitter 2270.

The receiver 2255 receives terminal performance information including IDC capable frequency information from the terminal 2200, and receives, from the terminal 2200, a proximity indication message including serving frequency information of a femtocell adjacent to the terminal. .

The identification unit 2260 determines whether the IDC generation frequency band and the serving frequency of the femtocell are a frequency band set in a network.

The transmitter 2270 measures the IDC related to the terminal 2200 based on whether the proximity indication message is received from the terminal 2200 and whether the proximity indication message includes information about a frequency band not set by the network. And transmit information for setting the triggering. At this time, if the base station 2250 does not receive the proximity indication message, it is to set the measurement and triggering based on the frequency band information that may exist IDC. At this time, if the base station 2250 receives the proximity indication message, but includes the information on the frequency band set by the network, the base station 2250 to set the measurement and triggering based on the frequency band information likely to exist IDC, additional RRC connection reset message Do not send. In addition, if the base station 2250 receives the proximity indication message and includes information about the frequency band not set by the network, a new RRC configured to perform measurement and triggering on the frequency band not set by the network. The connection reset message is transmitted to the terminal 2200.

The receiver 2255 receives IDC indication information and a measurement result from the terminal 2200.

The IDC solution selection unit 2265 selects an IDC solution based on the IDC indication information and the measurement result. At this time, the IDC solution may be an FDM operation or a TDM operation. The FDM operation or the TDM operation may be an operation according to FIGS. 5 to 13. For example, when a problem occurs in a frequency band provided by a base station, if the frequency band available according to the IDC indication information does not cause a problem due to load balancing and does not significantly affect handover (for example, For example, when the RSRP or RSRQ value of the corresponding frequency band is sufficiently large), the FDM operation may be performed. Otherwise, the TDM operation may be performed in the serving cell.

The transmitter 2270 transmits the selected IDC solution to the terminal 2200. At this time, the IDC solution may be transmitted through the RRC connection reconfiguration message. For example, the IDC resolution operation may include an operation of a blocking timer for prohibiting transmission of an IDC indication message (or a measurement report message) for a predetermined time. As another example, when the determined IDC solution is an FDM operation, a secondary serving cell is changed through a serving cell management operation (for example, deletion of a secondary serving cell in question). A handover procedure for changing the primary serving cell may be initiated. As another example, when the determined IDC solution is a TDM operation, a specific DRX pattern may be transmitted through an RRC connection reconfiguration message. As another example, when the determined IDC solution is a TDM operation, an indicator indicating that the DRX pattern is caused by IDC may be transmitted together with a specific DRX pattern through an RRC connection reconfiguration message. The measurement performed by the terminal according to the indication of the indicator may be changed differently than before. As another example, when the determined IDC solution is a TDM operation, HARQ retransmission in the LTE band may be rejected for handling of beacons while transmitting a signal in the ISM band. That is, the start of the IDC solution may be instructed through an IDC indication message (or a measurement report message).

On the other hand, if the IDC solution determined by the base station based on IDC indication information is the same as the existing IDC solution, the IDC solution transmission process may be omitted.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

Claims (14)

In a method of controlling a terminal in-device coexistence interference (IDC) in a wireless communication system,
Transmitting, to the base station, terminal performance information including frequency information capable of generating IDC;
Checking whether the frequency band capable of generating IDC is a frequency band set in a network;
Receiving measurement and triggering related setting information from the base station regarding the IDC possible frequency band;
Performing measurement and IDC triggering based on the verification result and the measurement and triggering related setting information; And
And transmitting a measurement report message including an IDC indication on whether IDC triggering is performed and a result of the measurement, to the base station. The method of claim 1,
And transmitting the proximity indication message including the serving frequency information of the femto cell to the base station when the terminal is close to the femto cell. 3. The method of claim 2,
If the serving frequency of the femto cell is not the frequency band set in the network, in-device coexistence interference control method characterized in that for receiving the measurement and triggering configuration information related to the serving frequency of the femto cell from the base station. The method of claim 3, wherein
The measurement and IDC triggering,
In-device coexistence interference control method characterized in that performed based on the measurement and triggering configuration information related to the serving frequency of the femto cell. In a terminal for controlling in-device coexistence interference (IDC) in a wireless communication system,
A transmitter for transmitting the terminal capability information including the frequency information of the IDC to the base station;
A confirmation unit for checking whether the frequency band capable of generating IDC is a frequency band set in a network;
A receiver configured to receive, from the base station, measurement and triggering related setting information regarding the IDC possible frequency band; And
A measurement and triggering unit configured to perform measurement and IDC triggering based on the check result and the measurement and triggering related setting information,
Wherein the transmission unit comprises:
And a measurement report message including an IDC indication on whether to perform the IDC triggering and a result of the measurement to the base station. The method of claim 5, wherein
Wherein the transmission unit comprises:
And when the terminal is close to the femto cell, transmitting a proximity indication message including serving frequency information of the femto cell to the base station. The method according to claim 6,
The receiver may further comprise:
If the serving frequency of the femto cell is not the frequency band set in the network, the terminal characterized in that for receiving the measurement and triggering configuration information related to the serving frequency of the femto cell from the base station. The method of claim 7, wherein
The measuring and triggering unit,
And measuring and triggering based on measurement and triggering configuration information related to the serving frequency of the femto cell. A method for controlling in-device coexistence interference (IDC) in a base station in a wireless communication system,
Receiving, from the terminal, terminal performance information including frequency information capable of generating IDC;
Receiving, by the terminal, a proximity indication message including serving frequency information of a femto cell in proximity from the terminal;
Checking whether the IDC frequency band and the serving frequency of the femtocell are a frequency band set in a network;
Transmitting measurement and triggering related setting information about the IDC possible frequency band based on the confirmation result to the terminal; And
And receiving, from the terminal, a measurement report message including an IDC indication and a measurement result for the IDC possible frequency. In a base station for controlling in-device coexistence interference (IDC) in a wireless communication system,
A receiver for receiving terminal capability information including frequency information capable of generating IDC from the terminal and receiving a proximity indication message including serving frequency information of a femto cell to which the terminal is located;
A confirmation unit confirming whether the IDC frequency band and the serving frequency of the femtocell are a frequency band set in a network; And
A transmitter for transmitting measurement and triggering related setting information to the terminal with respect to the frequency band capable of generating the IDC based on the confirmation result;
The receiver may further comprise:
The base station, characterized in that for receiving the measurement report message containing the IDC indication and the measurement result for the IDC possible frequency. 11. The method of claim 10,
And an IDC solution selection unit for selecting an IDC solution method based on the IDC indication and the measurement result.
Wherein the transmission unit comprises:
And transmitting the selected IDC solution. In a method of controlling a terminal in-device coexistence interference (IDC) in a wireless communication system,
Transmitting performance information of a terminal to a base station;
Selectively transmitting a proximity indication message using information on a frequency band in an RRC connection reconfiguration message received from the base station;
And transmitting information indicating that IDC is generated and a measurement result by IDC to the base station. The method of claim 12, wherein the step of selectively transmitting the proximity indication message using the information on the frequency band in the RRC connection reconfiguration message received from the base station,
Confirming that a frequency band into which the terminal enters is a frequency band that is not set by the base station through the received RRC connection reconfiguration message;
Transmitting the proximity indication message including information on the identified unset frequency band to a base station;
And receiving an RRC connection reconfiguration message including the unknown frequency by network from the base station. The method of claim 12, wherein the transmitting of the information indicating that the IDC is generated and the measurement result by the IDC to the base station,
And information indicating that IDC is generated in a frequency band included in an RRC connection reconfiguration message received from the base station and a measurement result by IDC.

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