KR102238502B1 - Apparatus and method for controlling interference in a wireless communication system - Google Patents

Abstract

The present invention is an interference control method of a base station (TP: Transmission Point) of a wireless communication system, wherein the TP receives a message including channel quality information for the TP from a terminal providing a communication service, and at least one peripheral A message including received power information for a reference signal received from the terminal is received from the TP, and a data rate for the terminal is determined based on the channel quality information and the received power information.

Description

Apparatus and method for interference control in a wireless communication system {APPARATUS AND METHOD FOR CONTROLLING INTERFERENCE IN A WIRELESS COMMUNICATION SYSTEM}

The present invention relates to a method and apparatus for controlling interference between channels in a wireless communication system.

In a wireless communication system, a base station estimates a channel state with a terminal, determines a data transmission rate, and transmits data according to the determined transmission rate. The base station may estimate a channel state with the terminal based on channel information directly estimated by the base station using information on a reception channel of the terminal received feedback from the terminal or a signal received from the terminal.

When estimating the channel state with the terminal based on the reception channel information fed back from the terminal, the reception channel information is received at a period determined according to a related standard of a communication system and its implementation. In addition, the base station estimates a channel state with the terminal based on the reception channel information of the terminal that is fed back from the terminal, and determines a transmission rate at the next transmission time for the terminal according to the estimated channel state.

Here, the received channel information includes information on the strength of the received signal from the serving base station or information indicating the quality of the received signal compared to peripheral interference, and the received channel information is, for example, a channel quality index (CQI). Can be displayed. In addition, the reception channel information indicates a channel state at a time when the terminal receives a related signal.

Meanwhile, in a wireless communication system to which an interference control technique is applied, the channel state must be changed according to whether an interference signal is controlled. In order to estimate the changed channel state, the channel information between the terminal and the neighboring base station must be used, but there is a limitation in acquiring the channel information due to the resource constraints between the terminal and the neighboring base station. There is.

The present invention provides a method and apparatus for controlling interference of a base station in a wireless communication system.

The method according to an embodiment of the present invention; In the interference control method of a base station (TP: Transmission Point) in a wireless communication system, the process of the TP receiving from the terminal 1 message including channel quality information for the TP providing a communication service to the terminal, The process of receiving, by the TP, from at least one neighboring TP, a second message including received power strength for a reference signal received from the terminal and downlink transmission power information of the at least one neighboring TP, and the reception And obtaining relative channel information based on power strength and downlink transmission power information, and determining a data rate for the terminal based on the channel quality information and the relative channel information.

An apparatus according to an embodiment of the present invention includes; In a base station (TP: Transmission Point) controlling interference in a wireless communication system, the TP receives from the terminal a first message including channel quality information for the TP providing a communication service to the terminal, and at least A receiver configured to receive a second message from one neighboring TP, including received power strength for a reference signal received from the terminal and downlink transmission power information of the at least one neighboring TP, and the received power strength and the downlink And a control unit for obtaining relative channel information based on link transmission power information, and determining a data rate for the terminal based on the channel quality information and the relative channel information.

The present invention allows a serving TP that provides a communication service to a terminal to determine a data rate for the terminal in consideration of an interference signal caused by a neighboring TP of the terminal, so that more accurate channel state information can be estimated.

1 is a diagram showing an example of signaling between a terminal and base stations in a wireless communication system according to an embodiment of the present invention;
FIG. 2 is a diagram illustrating an example in which a serving TP determines a data rate for a terminal in consideration of an interference signal received from a neighboring TP in a wireless communication system according to an embodiment of the present invention;
3 is a diagram showing an example of acquiring and exchanging channel information for channel estimation according to an embodiment of the present invention;
4 is a diagram illustrating an example of acquiring and exchanging channel information for channel estimation according to another embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, only parts necessary to understand the operation of the present invention will be described, and background technology other than that will be omitted so as not to obscure the subject matter of the present invention.

1 is a diagram illustrating an example of signaling between a terminal and base stations in a wireless communication system according to an embodiment of the present invention.

Referring to FIG. 1, the illustrated wireless communication system includes a terminal 120, a serving base station (TP) providing a communication service to the terminal 120, and a location around the terminal 120. It includes a plurality of surrounding TPs.

The serving TP 110 determines the data rate for the terminal 120, and it is possible to know whether the neighboring TPs 130 and 140 interfere with each other at the time of transmission to the terminal 120 through a separate method. A method for the serving TP 110 to learn whether the neighboring TPs interfere with the terminal 120 is to directly receive the interference control status of each TP from the neighboring TPs, or a separate coordinator that performs interference control information or commands as shown in FIG. 4. It can be a way to learn from. Whether the neighboring TPs 130 or 140 interfere is information on a transmission time unit, and may be information on data transmission of each TP for each sub-band constituting the frequency domain, and data transmission of each TP It may be the output level (or power level) information.

The reception channel information of the terminal that the serving TP 110 receives feedback from the terminal 120 may be a signal strength from the serving TP 110 and a signal strength compared to the peripheral interference caused by the neighboring TPs 130 and 140.

Channel information between the terminal 120 and the neighboring TP (130 or 140) is, the terminal 120 directly receives information on the neighboring TP (130 or 140) and feeds back to the serving TP (110), or uplink of the terminal It can be obtained by receiving (UL: Uplink) transmission information from a neighboring TP (130 or 140) and transmitting it to the serving TP (110).

When the terminal 110 directly receives information on the neighboring TP (130 or 140) and feeds it back to the serving TP (110), the information on the neighboring TP (130 or 140) is, for example, a measurement report (Measurement Report). It can be information. In addition, when the uplink transmission information of the terminal is received by the neighboring TP (130 or 140) and transmitted to the serving TP (110), the uplink transmission information of the terminal is, for example, a sounding reference signal (SRS: (Sounding Reference)) of the terminal. Signal) may be received information of the neighboring TP 130 or 140. In this case, the neighboring base station 130 or 140 compensates for the received power for the SRS with downlink (DL) transmission power, and the terminal 110 It is used as relative channel information between the and the neighboring TPs 130 or 140. In an embodiment of the present invention to be described later, relative channel information using SRS is referred to as an SRS value.

Channel information between the terminal 120 and the neighboring TPs 130 or 140 obtained by the above method is limited due to reasons such as transmission overhead in uplink resources. For example, according to the LTE (Long Term Evolution) standard, the number of reports on channel state information that can be fed back by the terminal is limited to 4 at the same time, and the number of TP measurement reports that can be fed back by the terminal is limited to 8 at the same time. It will be.

The transmission rate R for the terminal 120 is calculated as in Equation 1 below. That is, the transmission rate R of the serving base station A for terminal k is determined in consideration of a signal-to-interference-plus-noise ratio (SINR) between the terminal k and the serving TP (A).

In Equation 1, f denotes a function value for changing the SINR to match the transmission rate including the UE's reception gain, and OLRC denotes the UE's feedback, for example, Ack (acknowledge)/Nack (negative acknowledge) feedback. Represents a value to adjust the transmission rate based on. OLRC may be added to the SINR(A,k) value itself or may be added to the f(SINR(A,k)) value as shown in Equation 1.

In addition, RxP(A,k) represents the strength of the signal received by the terminal k from the serving TP (A), I_k represents the strength of the interference signal received by the terminal k from all neighboring TPs, and N Represents thermal noise. Here, each of the received signal strength and the interference signal strength may be, for example, received signal power and interference signal power.

SINR(A, k) is a value calculated based on channel information fed back from the UE, and is mainly calculated based on the CQI fed back from the UE. Here, a configuration in which the serving TP calculates the SINR based on the CQI fed back from the UE is described as an example, but the SINR is a precoding matrix index (PMI) or a rank index (RI) fed back from the UE. It can also be calculated based on.

The CQI fed back from the terminal may vary depending on interference control for an interference signal received from a neighboring TP and whether data is transmitted by a neighboring TP, etc., and in an embodiment of the present invention to be described later, feedback from the terminal is performed in the presence of all peripheral interference. It will be described assuming CQI.

Here, interference control refers to controlling the output (or power) of the downlink transmission signal of the neighboring TP transmitted using the same frequency band as the downlink reception signal received from the terminal. Such interference control may be performed by turning on/off the output of the data channel signal except for the control channel signal or by adjusting the output level (or power level) of the data channel signal. In addition, information signaled for interference control may be determined by each TP and exchanged between TPs or may be determined by a separate centralized coordinator entity and shared with all TPs. The channel state between the terminal and the neighboring TPs can be estimated based on I_k, which is the amount of interference that terminal k receives from all neighboring TPs. At this time, assuming that the strength of the interference signal received from the neighboring TP i is I(i, k), I_k is determined whether the neighboring TP knows the channel information to the terminal k as described in Equation 2 below. It is classified according to. In addition, I(i, k) becomes an SRS value or a measurement report value. When I(i,k) is a measurement report value, a TP using the same physical cell identifier (PCID) is recognized as one cell.

When at least two TPs transmit signals using the same PCID and support Multiple Input Multiple Output (MIMO) transmission, that is, at least two TPs transmit a plurality of data streams to one terminal, and the terminal serves TP When the number of data streams is different from the signal used to estimate the channel information for I_k, this may be corrected when I_k is calculated.

Assuming that the TP to which interference control is applied among the neighboring TPs is i_c, the SINR considered in calculating the transmission rate for the terminal of the serving TP is calculated as in Equation 3 below.

In Equation 3, RxP(A,k) denotes the strength of the signal received from the serving TP(A) by the terminal k, and I(i_k, k) denotes all neighboring TPs except the serving TP by the terminal k. Among them, the strength of the interference signal received from the TP i_k, which knows the channel information to the terminal (k), represents the strength of the TP to which the interference control is applied compared to the output of the transmitted signal of the TP to which the interference control is not applied. Represents the relative ratio of the output to the transmitted signal, I(i_c,k) represents the strength of the interference signal received from the neighboring TP to which the terminal (k) has applied interference control, and I (i_u, k) represents the terminal (k ) Represents the strength of an interference signal received from a TP i_u that does not know channel information to the terminal k among all neighboring TPs except the serving TP.

The alpha(i_c) is determined between (0, 1) and may have multiple values for one TP according to an interference control scheme. In order to calculate the transmission rate according to the interference control in this way, information on the strength of the interference signal for TP i_u whose channel information is unknown, such as ΣI(i_u,k) + N in Equation 3, must be provided. A variable NI representing the strength of the interference signal for TP i_u whose channel information is unknown is calculated as shown in Equation 4 below.

In Equation 4, RxP(A,k) represents the strength of the signal received from the serving TP A by the terminal k, SINR_cqi(A,k) represents the channel quality information of the serving TP A fed back by the terminal k, and I (i_k, k) denotes the strength of an interference signal received from TP i_k in which the terminal k knows channel information to the terminal k among all neighboring TPs except the serving TP. The NI may be used after filtering an Infinite Impulse Response (IIR), and may be corrected as shown in Equation 5 below according to the difference between the CQI used in the NI calculation and the SRS or the measurement time point of the measurement report.

If Equation 4 is applied to Equation 3, it can be expressed as Equation 6 below.

In Equation 6, RxP(A,k) denotes the strength of the signal received from the serving TP A by the terminal k, and I(i_k, k) denotes the terminal ( k) indicates the strength of the interference signal received from the TP i_k, which knows the channel information to k), and alpha(i_c) is the output of the transmission signal of the TP to which the interference control is not applied versus the transmission signal of the TP to which the interference control is applied. Represents the relative ratio of the output, and I(i_c,k) represents the strength of the interference signal received from the neighboring TP to which the terminal k has applied interference control, and NI is the interference signal strength for the TP i_u, whose channel information is unknown. Represents.

Each part of Equation 6 may be replaced with an SRS reception value or a measurement report value in the related TP. That is, RxP(A,k), I(i_k,k), I(i_c,k) can all be replaced with the SRS reception value or the measurement report value, and NI is the SRS reception value or the measurement report value in Equation 4 It is converted to the equation used. When using the measurement report value, the same PCID can be applied to a plurality of TPs. Thereafter, the serving TP calculates the transmission rate for terminal k by applying SINR(A,k)' calculated by Equation 6 to Equation 1, and a modulation and coding scheme (MCS) to be used for transmission and Determine the transport block size. In this case, different values of OLRC(k) in Equation 1 may be applied according to the interference control mode.

Equation 6 may be modified as in Equation 7 below when n TPs simultaneously transmit the same information to one terminal. That is, the strength RxP(A_jt,k) of the signal received by the terminal k from TP A_jt increases by the number of TPs. Here, A_jt represents a set of TPs that simultaneously transmit information to terminal k. As an example, when n TPs simultaneously transmit different information to one terminal, each signal is separated separately, so the SINR considered in calculating the transmission rate for the terminal of the serving TP is calculated according to Equation 6. In addition, when n TPs transmit signals to one terminal, all TPs A_jt are excluded from I(i_k, k).

2 is a diagram illustrating an example in which a serving TP determines a data rate for a terminal in consideration of an interference signal received from a neighboring TP in a wireless communication system according to an embodiment of the present invention.

Referring to FIG. 2, the serving TP receives the CQI fed back from the UE in step S212, and calculates the data rate R for the UE through Equation 1 as an example in step S214.

In addition, the serving TP calculates a first SINR between the terminal and the serving TP based on the transmission signal including the terminal reception gain in step S216, and removes the terminal reception gain from the transmission signal. Here, the terminal reception gain means an additional gain excluding a gain for a signal received from the serving TP, and typically has an antenna gain. In addition, the serving TP calculates a second SINR between the terminal and the serving TP based on the transmission signal from which the terminal reception gain is removed in step S218. Thereafter, the serving TP corrects the second SINR through Equations 2 to 7 as an example in step S220.

In step S222, the serving TP calculates a first SINR' between the terminal and the serving TP based on the transmission signal from which the terminal reception gain has been removed through Equation 7 as an example, and adds the terminal reception gain to the transmission signal. The first and second SINRs calculated above refer to SINRs calculated without considering the interference signal, and are separated from the first SINR', and the first SINR' and the second SINR' to be described later are It means the calculated SINR.

In addition, the serving TP calculates the second SINR' between the terminal and the serving TP based on the transmission signal to which the terminal reception gain is added in step S224, and calculates the transmission rate R'for the terminal in consideration of the second SINR' in step S226. do. The previously calculated transmission rate R refers to a transmission rate calculated without considering the interference signal, and is distinguished from the transmission rate R′, and R’ indicates a transmission rate calculated considering the interference signal.

Thereafter, the serving TP calculates a metric to be used for transmission and determines the MCS.

3 is a diagram illustrating an example of acquiring and exchanging channel information for channel estimation according to an embodiment of the present invention.

Referring to FIG. 3, the terminal 301 feeds back a message including an index indicating channel quality information such as CQI, PMI, or RI to the serving TP 303 (step 310). It includes information on the ratio of the signal of the serving TP measured in the resource designated by (303) and the interference signal to the neighboring TP. In addition, the terminal 301 feeds back interference channel information about the interference channel to the serving TP 303 in addition to the channel quality information (step 320). Refers to information measured based on a downlink (DL) reference signal (RS) received from.

Around TP (305) is a terminal 301 is to receive a UL RS, and (step 330) processing the separation of the receive power strength of the received UL RS or the reception power intensity value itself for transmitting _UL E_ _It is transmitted to the serving TP 303 in the form of _{RS. (Step 340) The E_ UL The RS} form will be described in more detail through Table 1 below. The information transmitted in step 340 may be UL RS information received by all TPs, and therefore, the serving TP 303 uses the information transmitted in step 340 to determine the distance information between the terminal 301 and each TP or the path loss of the wireless channel. It can be recognized as (path loss) information.

In addition, the UL RS of the terminal 301 may be received by the serving TP 303, and each of the neighboring TP 305 and the serving TP 303 may receive UL RSs of all receivable terminals. Nearby TP information or terminal information required for UL RS reception may be shared between related TPs through a separate procedure.

The neighboring TP information required for the UL RS reception of the terminal 301 includes at least one of PCID information, information on the time domain and frequency domain of the UL RS resource used by the related TP, and information related to cyclic shift. Can be included. In addition, the terminal information required for UL RS reception may include information on a time domain and a frequency domain of a UL RS resource used by a terminal receiving a communication service through a related TP, information related to cyclic shift, and the like.

When the neighboring TP 305 transmits the received power intensity of the UL RS of the terminal 301 to the serving TP 303, it transmits a value processed by using the received power intensity of the DL RS of the neighboring TP 305, or The received power strength of the RS is transmitted together so that it can be directly processed and used by the serving TP (303). In addition, the neighboring TP 305 transmits the UL RS reception information of not only the terminal 301 but also all the terminals to which each terminal belongs to a serving TP. The neighboring TP 305 may share the UL RS reception information of all the received terminals with all other neighboring TPs, or share the UL RS reception information of the terminal 301 only to the serving TP 303 using the shared information. . Since the amount of information on the UL RS reception information and the load on the link between TPs are proportional, each terminal can reduce the load on the link between TPs by sharing the UL RS reception information only with the serving TP to which it belongs.

UL RS reception information transmitted from the neighboring TP 305 to the serving TP 303 in step 340, that is, E_ _{UL RS} Form and the above E_ _{UL RS} Among the information constituting the form, information included in the received SRS_power may be represented as shown in Table 1 below.

As shown in Table 1 above, E_ _{UL RS} The type includes Serving TP ID, Received TP ID, Received SRS_power[ ], and Received TP DL_Tx_Power. Here, the Serving TP ID represents the ID (ID) of the serving TP 303, the Received TP ID represents the ID of the neighboring TP 305 that received the UL RS, and the Received SRS_power[] is received from all neighboring TPs. It represents one UL RS information set, and Received TP DL_Tx_Power represents downlink transmission power of the neighboring TP 305.

In addition, the Received SRS_power[] includes Received time, Received frequency, Received cyclic shift, Received comb, and Received power. Here, Received time represents the time when the UL RS is received from the terminal 301, Received frequency represents the frequency section information at which the UL RS is received, and Received cyclic shift represents the cyclic shift information for the UL RS, and Received comb represents the resource information to which the SRS is allocated, and Received power represents the received power strength for the UL RS.

For example, assuming that the time period for receiving the UL RS between the serving TP 303 and the neighboring TP 305 is divided, and the UEs of the corresponding TP divide the UL RS resource into a frequency section and a cyclic shift, the serving TP 303 may detect a terminal matching the received SRS_power without specifying a separate terminal ID. That is, resources classified by time period, frequency section, and cyclic shift information are matched to one terminal. In addition, the downlink transmission power of the neighboring TP 305 is transmitted to another neighboring TP whenever the transmission power is changed through a separate message.

_{E_ UL} from peripheral TP (305) Serving TP (303) receiving the _{RS is the E_ UL} A terminal matching Received_SRS_power included in the _{RS is detected.} In addition, the serving TP 303 processes the received power strength of the UL RS for the detected terminal, that is, the terminal 301 and the downlink transmission power of the neighboring TP 305, Acquires the relative channel information of. Here, the processing of downlink transmission power for obtaining relative channel information may be expressed as a product of the received power strength of the UL RS of the neighboring TP 305 and the downlink transmission power.

For the relative channel information, a range of values is adjusted to replace each part of Equation 6 with an SRS received value. That is, if the RxP value representing the downlink received signal strength (or power) value of the serving TP 303 or the neighboring TP 305 is known, the relative channel information for the corresponding TP is known based on the RxP value and the SRS received value. A calculation formula for obtaining the coefficient a and a calculation formula for substituting I(i_k, k) of Equation 6 for the remaining SRS received values using the relative coefficient a are as shown in Equation 8 below.

In Equation 8, SRS_received_power(A,k) represents the power of the SRS received by the terminal k from the serving TP A, and RxP(A,k) represents the power of the signal received by the terminal k from the serving TP (A). And SRS_received_power(B,k) represents the power of the SRS received by the terminal k from the serving TP B. SRS_received_power(A,k) and RxP(A,k) considered in calculating the relative coefficient a are information fed back from the terminal, and SINR is a proportional value, so adjusting the range of the SRS reception value will replace all values with the SRS reception value. In some cases, it may not be used.

4 is a diagram illustrating an example of acquiring and exchanging channel information for channel estimation according to another embodiment of the present invention.

Referring to FIG. 4, the terminal 401 feeds back a message including an index indicating channel quality information such as CQI, PMI, or RI to the serving TP 403. (Step 410) The channel quality information includes the serving TP. It includes information on the ratio of the signal of the serving TP measured in the resource designated by (403) and the interference signal to the neighboring TP. In addition, the terminal 401 feeds back interference channel information on the interference channel to the serving TP 403 in addition to the channel quality information (step 420). Refers to information measured based on a downlink (DL) reference signal (RS) received from.

The terminal 401 transmits the UL RS to the neighboring TP 405 (step 430). At this time, the UL RS may be received by all the neighboring TPs that can be received, including the serving TP 403. Around TP (405) passes the UL RS information received by the adjustment section (coordinator) (407). (Step 450) according to the UL case, the information transmitted from the RS 450 step E_ _UL It may be transmitted in the form of _{RS ' or E_ UL It} can also be delivered in the form of an RS.

In addition, the coordinator 407 may generate interference control information by using the scheduling information transmitted from each TP separately from the UL RS information received in step 450, and transmits the received UL RS information to each serving TP belonging to each terminal. do. That is, the controller 407 transmits the received UL RS information to the serving TP 403 to which the terminal 401 belongs.

UL RS information transmitted in step 450 is E_ _{UL When} transmitted in the form of RS', the type of information transmitted to the adjustment unit 407 and the type of information transmitted to the serving TP 403 by the adjustment unit 407 may be different.

For example, the peripheral TP 405 may transmit the received UL RS information to the controller 407 without processing. This has the effect of causing a separate entity in the adjustment unit to perform a processing operation added due to information processing that the surrounding TP 405 needs to perform. In this case, the neighboring TP 405 receiving the UL RS signal from the terminal 401 transmits the UL RS information E_ _{UL RS} ' It can be transmitted to the adjustment unit 407 in the form. E_ _{UL above RS} ' form and the E_ _{UL Information included in Received SRS_power among information constituting the RS} ' type may be represented as shown in Table 2 below.

As shown in Table 2 above, E_ _{UL RS} ' type includes Received TP ID, Received SRS_power[ ], and Received TP DL_Tx_Power. Here, Received TP ID represents the ID of the neighboring TP 405 that has received the UL RS, Received SRS_power[] represents the set of UL RS information received from all neighboring TPs, and Received TP DL_Tx_Power is the downlink of the neighboring TP 405. Indicates the link transmission power.

In addition, the Received SRS_power[] includes Received time, Received frequency, Received cyclic shift, Received comb, and Received power. Here, Received time represents the time when the UL RS is received from the terminal 401, Received frequency represents the frequency section information at which the UL RS is received, and Received cyclic shift represents the cyclic shift information for the UL RS, and Received comb represents the resource information to which the SRS is allocated, and Received power represents the received power strength for the UL RS.

In addition, the controller 407 may obtain relative channel information between the terminal 401 and the neighboring TPs 405 by processing the received UL RS information and downlink transmission power of the neighboring TPs 405. To do this the relative channel information obtained may be used for interference control information generation, _UL E_ _It is delivered to the serving TP 403 in the form of RS. E_ _{UL above RS} type and E_ _{UL above RS} Information included in Received SRS_power among the information constituting the form has been described in detail through Table 1 above, and thus a detailed description thereof will be omitted here.

Meanwhile, although specific embodiments have been described in the detailed description of the present invention, various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention is limited to the described embodiments and should not be defined, and should be defined by the scope of the claims and equivalents as well as the scope of the claims to be described later.

In addition, it will be appreciated that the interference control method according to the embodiment of the present invention can be realized in the form of hardware, software, or a combination of hardware and software. Any such software may be, for example, a volatile or non-volatile storage device such as a storage device such as a ROM, or a memory device such as a RAM, memory chip, device or integrated circuit, for example, whether erasable or rewritable. Or, for example, it may be optically or magnetically recordable, such as a CD, DVD, magnetic disk or magnetic tape, and stored in a storage medium readable by a machine (eg, a computer). The graphic screen update method of the present invention may be implemented by a computer or portable terminal including a control unit and a memory, and the memory is a machine suitable for storing a program or programs including instructions for implementing the embodiments of the present invention. You can see that it is an example of a readable storage medium.

Accordingly, the present invention includes a program including code for implementing the apparatus or method described in any claim of the present specification, and a machine (computer, etc.) readable storage medium storing such a program. In addition, such a program may be electronically transferred through any medium, such as a communication signal transmitted through a wired or wireless connection, and the present invention suitably includes equivalents thereto.

In addition, the apparatus for controlling interference according to an embodiment of the present invention may receive and store the program from a program providing device connected by wire or wirelessly. The program providing device performs wired or wireless communication with the graphic processing device and a program including instructions for performing a preset content protection method, a memory for storing information necessary for the content protection method, and the like. It may include a communication unit for performing, and a control unit that automatically transmits a corresponding program to the transmission/reception device at the request of the graphic processing device.

Claims (18)

In the interference control method of a base station (TP: Transmission Point) in a wireless communication system,
The process of receiving, by the TP, from the terminal 1 message including channel quality information for the TP providing a communication service to the terminal,
The process of receiving, by the TP, from at least one neighboring TP, a second message including a received power strength for a reference signal received from the terminal and downlink transmission power information of the at least one neighboring TP; and
A process of obtaining relative channel information based on the received power strength and the downlink transmission power information, and
And determining a data rate for the terminal based on the channel quality information and the relative channel information.
The method of claim 1,
The channel quality information indicates a ratio of the strength of the TP signal measured in the resource region designated by the TP and the strength of the interference signal due to the at least one neighboring TP.
The method of claim 2,
The interference signal strength is calculated in consideration of the strength of an interference signal received from a first neighboring TP that knows channel information to the terminal and an interference signal strength received from a second neighboring TP that does not know channel information to the terminal. Interference control method.
The method of claim 3,
The interference signal strength (I_k) is the following equation
I_k=∑I(i_k,k) + ∑I(i_u,k)
Is calculated by
The k is an index indicating the terminal, the i_k is an index indicating a TP that knows channel information to the terminal k among all neighboring TPs except the TP, and i_u is all neighboring TPs except the TP Is an index indicating the TP of which the channel information to the terminal k is unknown, and ∑I(i_k,k) represents the sum of the strengths of the interference signals received from the TP(i_k) by the terminal k, and the ∑ I(i_u,k) denotes the sum of the strength of the interference signal received from the TP(i_u) by the terminal k.
The method of claim 1,
The second message further includes at least one of an identifier (ID) of the TP, an ID of the at least one neighboring TP, and downlink transmission power related information of the at least one neighboring TP. Way. The method of claim 1,
The received power strength includes at least one of time section information, frequency section information, cyclic shift-related information, and resource information to which the reference signal is allocated for a signal received from the terminal.
The method of claim 6,
Further comprising the step of detecting the terminal in consideration of at least one of the time interval information, the frequency interval information, and the cyclic shift related information,
The interference control method, characterized in that the resource classified by at least one of the time interval information, the frequency interval information, and the cyclic shift related information is matched to a specific terminal.
The method of claim 1,
The relative channel information is calculated by multiplying the received power strength by the downlink transmission power of the at least one neighboring TP.
The method of claim 1,
And when the second message is received through a coordinating unit, receiving relative channel information of a neighboring TP associated with the terminal from the coordinating unit.
In a base station (TP: Transmission Point) controlling interference in a wireless communication system,
The TP receives a first message including channel quality information for the TP providing a communication service to the terminal from the terminal, and received power strength for a reference signal received from the terminal from at least one neighboring TP And a receiver for receiving a second message including downlink transmission power information of the at least one neighboring TP; and
And a control unit for obtaining relative channel information based on the received power strength and downlink transmission power information, and determining a data rate for the terminal based on the channel quality information and the relative channel information.
The method of claim 10,
And the channel quality information indicates a ratio of the strength of the TP signal measured in the resource region designated by the TP and the strength of the interference signal due to the at least one neighboring TP.
The method of claim 11,
The interference signal strength is calculated in consideration of the strength of an interference signal received from a first neighboring TP that knows channel information to the terminal and an interference signal strength received from a second neighboring TP that does not know channel information to the terminal. TP.
The method of claim 12,
The interference signal strength (I_k) is the following equation
I_k=∑I(i_k,k) + ∑I(i_u,k)
And k is an index indicating a terminal, and i_k is an index indicating a TP that knows channel information to the terminal k among all neighboring TPs except the TP, and i_u is the TP. It is an index indicating a TP that does not know channel information to the terminal (k) among all neighboring TPs except for, and ∑I(i_k,k) is the sum of the strength of the interference signal received from the terminal (k) from TP And ΣI(i_u,k) denotes the sum of the strengths of the interference signals received from the TP(i_u) by the terminal k.
The method of claim 10,
The second message further includes at least one of an identifier of the TP, an ID of the at least one neighboring TP, and downlink transmission power related information of the at least one neighboring TP.
The method of claim 10,
The received power strength includes at least one of time interval information, frequency interval information, cyclic shift related information, and resource information to which the reference signal is allocated for a signal received from the terminal.
The method of claim 10,
The relative channel information is calculated by multiplying the received power strength by the downlink transmission power of the at least one neighboring TP.
The method of claim 15,
The control unit,
Detecting the terminal in consideration of at least one of the time interval information, the frequency interval information, and the cyclic shift related information,
TP, characterized in that the resource classified by at least one of the time period information, the frequency section information, and the cyclic shift related information is matched to a specific terminal.
The method of claim 10,
TP, characterized in that when the second message is received through a coordination unit, the receiving unit receives relative channel information of a neighboring TP related to the terminal from the coordination unit.

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