JP5820746B2 - Base station apparatus, terminal determination processing apparatus, terminal determination method, and computer program - Google Patents

Description

The present invention relates to a base station device, a terminal determination processing device, a terminal determination method, and a computer program.

  In recent years, with the rapid spread of mobile terminals such as smartphones and tablet terminals, there has been a situation in which wireless facilities possessed by telecommunications carriers are tightened due to a rapid increase in mobile traffic. As one of countermeasures, a heterogeneous network (hereinafter referred to as “HetNet”) has been studied (see, for example, Non-Patent Document 1). In HetNet, pico base stations and femto base stations that are smaller and have a lower transmission output than macro base stations are placed in an overlay manner in hot spots where traffic is concentrated in the service area (coverage area) of the macro base station.

  Conventionally, "LTE (Long Term Evolution)" is known as one of the standards studied by 3GPP (Third Generation Partnership Project) (see Non-Patent Documents 2 and 3, for example). Cell range expansion (CRE) technology and time division multiplexing interference control technology are being studied.

CRE technology is one of the load balancing methods in LTE. Here, the CRE technology will be described. The terminal selects a base station to be connected at startup. The terminal measures the received power of the reference signal transmitted by the neighboring base station, and connects to the base station having the maximum measured value. This is expressed by equation (1).
s (j) = arg max (B (i) P (i, j)) (1)
Here, s (j) is the connection base station ID of terminal j. P (i, j) is the received power of the reference signal of the base station i at the terminal j. B (i) is the “CRE bias value” of base station i.

  In HetNet, when promoting traffic offload from a macro base station to a pico base station, as a CRE technique, the CRE bias value of the macro base station is set to 1, and the CRE bias value of the pico base station is set to a value larger than 1. Set. This makes it easier for the terminal to connect to the pico base station than to the macro base station.

  Time division multiplexing interference control technology is a technology that avoids radio wave interference from interfering stations for downlink (direction from base station to terminal) communication in HetNet by instantaneously stopping the interfering station. It is. FIG. 5 is an explanatory diagram of the time division multiplexing interference control technique. In FIG. 5, the pico base station 200 is arranged in the coverage area 110 of the macro base station 100 that is an interfering station. The coverage area (pico cell) of the pico base station 200 is expanded from the area 210 to the area 220 by CRE technology.

  FIG. 5 (1) shows the status of the timing at which the macro base station 100 transmits radio waves (macro station transmission timing). At the macro station transmission timing, the pico base station 200 does not transmit a packet to a specific terminal 310 among the terminals 300 and 310 connected thereto. This specific terminal 310 is a terminal that is assumed to cause inconvenience in downlink communication due to radio wave interference caused by radio waves transmitted by the macro base station 100. For example, the specific terminal 310 is located at the end of the extended coverage area 220 of the pico base station 200, and the interference wave from the macro base station 100 is received much stronger than the desired wave from the pico base station 200. Is mentioned.

  FIG. 5 (2) represents the situation of the timing at which the macro base station 100 does not transmit radio waves (macro station stop timing). At the macro station stop timing, the pico base station 200 transmits a packet to the terminals 300 and 310 connected to itself. Therefore, the pico base station 200 also transmits a packet to the specific terminal 310 at the macro station stop timing.

D. Lopez-Perez, et al., “Enhanced Intercell Interference Conference Coordination Challenges in Heterogeneous Networks,” IEEE Wireless Commun., Vol.18, no.3, pp.22-30, Jun. 2011. http://www.3gpp.org/ S. Sesia, et al., LTE, The UMTS Long Term Evolution, Wiley, Apr. 2009.

  However, in the time division multiplexing interference control technique described above, a terminal that does not perform downlink communication at the macro station (interfering station) transmission timing and performs downlink communication at the macro station (interfering station) stop timing. Appropriately determining the problem is a problem.

The present invention has been made in consideration of such circumstances. In the time division multiplexing interference control technology, downlink communication is not performed at the transmission timing of the interfering station, and at the stop timing of the interfering station. It is an object of the present invention to provide a base station device, a terminal determination processing device, a terminal determination method, and a computer program that can appropriately determine a terminal that performs downlink communication.

In order to solve the above problems, a base station apparatus according to the present invention is a base station apparatus that avoids radio wave interference from an interfering station for downlink communication by time division multiplexing interference control technology. A terminal determination processing device that determines a first terminal to be avoided by a time division multiplexing interference control technique and a second terminal other than the first terminal; and a radio packet scheduler unit, wherein the terminal determination The processing apparatus includes a first determination unit that determines a difference between the downlink communication quality in the wideband and the downlink communication quality in the subband for the determination target terminal, and the difference is based on the reference. the judgment target terminal if you meet is determined that the second terminal, determines that the terminal to be determined if the difference does not meet the criteria as a first terminal, the radio packet The scheduler unit performs radio packet scheduling for the second terminal at a timing when the interfering station transmits radio waves according to a determination result of the terminal determination processing device, and at a timing when the interfering station does not transmit radio waves. Radio packet scheduling is performed on terminals including the first terminal .

Terminal determining processing apparatus according to the present invention includes a first terminal that is the subject to avoid the time radio interference division multiplexing interference control technology from interfering station for downlink communications, the second than the first terminal 1 is a terminal determination processing device that determines a difference between a wideband downlink communication quality and a subband downlink communication quality for a determination target terminal. A determination target terminal is determined to be the second terminal when the difference satisfies the criterion, and the determination target terminal is the first terminal when the difference does not satisfy the criterion A second determination unit that determines a threshold value of downlink communication quality in the wideband related to the determination target terminal, and the downlink communication quality in the wideband is based on a reference. Full And if the difference satisfies the criterion even if the downlink communication quality in the wideband does not satisfy the criterion, the terminal to be determined is determined to be the second terminal, When the downlink communication quality in the wideband does not satisfy the standard and the difference does not satisfy the standard, the terminal to be determined is determined to be the first terminal.

  In the terminal determination processing device according to the present invention, determination with the first terminal or the second terminal based on the previous determination result regarding the determination target terminal or MR (Measurement Report) fed back from the determination target terminal. Depending on the result, different threshold values are used in the threshold determination.

  In the terminal determination processing device according to the present invention, the latest information of wideband communication quality information representing downlink communication quality in the wideband, and the latest of subband communication quality information representing downlink communication quality for each subband. A difference calculation unit that calculates the difference using information is provided.

  In the terminal determination processing device according to the present invention, the timing for starting the process of determining the first terminal and the second terminal is a different period in a place where the peripheral environment of the terminal changes or where the moving speed of the terminal is different. It is characterized by that.

  In the terminal determination processing device according to the present invention, the information indicating the downlink communication quality in the wideband is a wideband CQI, and the information indicating the downlink communication quality in the subband is a subband CQI. It is characterized by that.

The base station apparatus according to the present invention, avoided in the base station apparatus to avoid the time-division multiplex-type interference control technology radio interference from interfering station for downlink communications by time division multiplexing interference control technique the interference A terminal determination processing device that determines a first terminal that is a target to be performed and a second terminal other than the first terminal, and a wireless packet scheduler unit, wherein the terminal determination processing device is a terminal to be determined Whether the frequency selectivity is strong or not is determined. When the frequency selectivity is strong, the terminal to be determined is determined as the second terminal, and when the frequency selectivity is weak. determines the terminal to be determined and the first terminal, the wireless packet scheduler unit, according to the determination result of the MS determination processing unit, at a timing when the interfering station transmits a radio wave a second terminal Performs radio packet scheduling in the target, the interfering station performs wireless packet scheduling directed to a terminal including a first terminal at a timing that does not transmit a radio wave, it is characterized.

Terminal determination method according to the present invention is a terminal determination method of a base station apparatus to avoid the time radio interference division multiplexing interference control technology from interfering station for downlink communications, time division multiplexing the radio interference A terminal determination step of determining a first terminal to be avoided by the interference control technique and a second terminal other than the first terminal, and a radio packet scheduling step, wherein the terminal determination step includes: The difference between the downlink communication quality in the wideband and the downlink communication quality in the subband relating to the target terminal is determined as a threshold, and if the difference satisfies the criterion, the determination target terminal is It determines that the terminal determines the terminal to be determined to be the first terminal if the difference does not meet the criteria, the wireless packet scheduling stearate According to the determination result of the terminal determination step, radio packet scheduling is performed for the second terminal at the timing when the interfering station transmits radio waves, and the first is performed when the interfering station does not transmit radio waves. The wireless packet scheduling is performed for terminals including the terminal of the above.
The terminal determination method according to the present invention includes a first terminal that is a target for avoiding radio wave interference from an interfering station for downlink communication by time division multiplexing interference control technology, and a second terminal other than the first terminal. A terminal determination method for determining a terminal, wherein a difference between a downlink communication quality in a wideband and a downlink communication quality in a subband related to a determination target terminal is determined as a threshold, and the difference is a reference It is a terminal determination method that determines that the terminal to be determined is the second terminal if the difference is satisfied, and determines that the terminal to be determined is the first terminal if the difference does not satisfy the criterion. Then, the communication quality of the downlink in the wideband related to the determination target terminal is determined as a threshold value, and the downlink communication quality in the wideband satisfies the standard, and the downlink communication in the wideband. Even if the quality does not meet the standard, if the difference meets the standard, the terminal to be determined is determined to be the second terminal, and the downlink communication quality in the wideband does not meet the standard And when the said difference does not satisfy | fill a reference | standard, it determines with the terminal of determination object being a 1st terminal.

A computer program according to the present invention provides a computer of a base station apparatus that avoids radio wave interference from an interfering station with respect to downlink communication by time division multiplexing interference control technology, and the radio wave interference is transmitted by time division multiplexing interference control technology. A computer program for executing a terminal determination step for determining a first terminal to be avoided and a second terminal other than the first terminal, and a radio packet scheduling step , wherein the terminal determination The step determines a threshold value of the difference between the downlink communication quality in the wideband and the downlink communication quality in the subband for the determination target terminal , and the determination target is satisfied when the difference satisfies the criterion. When the terminal is determined to be the second terminal and the difference does not satisfy the standard, the determination target terminal is the first terminal It determined, and the wireless packet scheduling step, according to the determination result of the terminal determining step, at a timing when the interfering station transmits a radio wave performs wireless packet scheduling intended for the second terminal, the interfering station The wireless packet scheduling is performed for terminals including the first terminal at a timing when the radio wave is not transmitted .
The computer program according to the present invention includes a first terminal that is a target for avoiding radio wave interference from an interfering station for downlink communication by a time division multiplexing interference control technique, and a second terminal other than the first terminal. Is a computer program for performing a terminal determination process for determining a difference between a downlink communication quality in a wideband and a downlink communication quality in a subband for a determination target terminal. When the difference satisfies the criterion, the terminal to be determined is determined to be the second terminal, and when the difference does not satisfy the criterion, the terminal to be determined is determined to be the first terminal. , Step and threshold determination of the downlink communication quality in the wideband for the terminal to be determined, and if the downlink communication quality in the wideband meets the criteria, If the difference satisfies the standard even if the downlink communication quality in the wideband does not satisfy the standard, the terminal to be determined is determined to be the second terminal, and the downlink in the wideband A computer for causing the computer to execute a step of determining that the terminal to be determined is the first terminal when the communication quality of the link does not satisfy the standard and the difference does not satisfy the standard. It is a program.

  According to the present invention, in the time division multiplexing interference control technology, it is possible to appropriately determine a terminal that does not perform downlink communication at the transmission timing of the interfering station and performs downlink communication at the stop timing of the interfering station. The effect that it can do is acquired.

It is a block diagram which shows the structural example of the base station apparatus which concerns on one Embodiment of this invention. It is a flowchart of the terminal determination process which concerns on one Embodiment of this invention. It is an example of the relationship between geometry and W-SINR. It is an example of the relationship between W-SINR and S-SINR. It is explanatory drawing of a time division multiplexing type interference control technique.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram illustrating a configuration example of a base station apparatus according to an embodiment of the present invention. FIG. 1 shows a configuration related to a downlink radio packet scheduling function of a base station apparatus.

  The base station apparatus shown in FIG. 1 avoids radio wave interference from an interfering station for downlink communication in HetNet by using time division multiplexing interference control technology. The base station apparatus shown in FIG. 1 is, for example, a pico base station 200 arranged in the coverage area 110 of the macro base station 100 in HetNet as shown in FIG. 5, and the coverage area is expanded by CRE technology. In addition, radio interference from the macro base station 100 for downlink communication is avoided by time division multiplexing interference control technology.

  In FIG. 1, the terminal determination processing device 1 uses MR (Measurement Report) and CSI (Channel State Information), does not perform downlink communication at macro station transmission timing, and performs downlink communication at macro station stop timing. A terminal that performs communication (hereinafter referred to as A terminal) is determined. The radio packet scheduler 2 performs radio packet scheduling for terminals other than the A terminal (hereinafter referred to as B terminal) at the macro station transmission timing according to the determination result of the terminal determination processing device 1, and performs macro station stop timing. Then, radio packet scheduling is performed for terminals including the A terminal.

  The downlink traffic channel radio resource allocation unit 4 allocates radio resources to the radio packet generated by the downlink traffic channel radio packet generation unit 3 according to the scheduling result of the radio packet scheduler unit 2.

  MR and CSI are input to the terminal determination processing device 1. MR and CSI are specified in LTE. MR is information indicating a downlink state that is configured from a result obtained by receiving and measuring a reference signal transmitted from a base station and fed back from the terminal to the base station. One characteristic of MR is that it is information that is fed back irregularly. The MR is fed back only when the terminal transitions to a special state, such as when the terminal is turned on, or when the terminal moves to a cell boundary and needs to be handed off to an adjacent cell.

  CSI is information representing a downlink state that is periodically fed back from a terminal to a base station. In LTE, CSI is composed of CQI (Channel Quality Indicator), RI (Rank Indicator), and PMI (Precoding Matrix Indicator). CQI is information obtained by quantizing SINR (Signal to Interference plus Noise Ratio).

  There are two types of CQI: wideband CQI (hereinafter referred to as W-SINR) and subband CQI (hereinafter referred to as S-SINR). W-SINR represents the average SINR of the entire system bandwidth. W-SINR is wideband communication quality information indicating downlink communication quality in the wideband. S-SINR represents SINR for each frequency resource block called a subband. S-SINR is subband communication quality information indicating downlink communication quality for each subband.

  RI represents applicability of MIMO (Multiple-Input Multiple-Output) transmission. In downlink MIMO in which there are two base station transmission antennas and two terminal reception antennas, RI takes a value of 1 or 2. When RI is 2, it indicates that the radio link is suitable for two streams of spatial multiplexing. When RI is 1, it indicates that the radio link is suitable for 1-stream transmission by space diversity. PMI represents an index of transmission weight suitable for MIMO transmission.

  With reference to FIG. 2, the operation of the terminal determination processing apparatus 1 shown in FIG. 1 will be described. FIG. 2 is a flowchart of terminal determination processing according to the present embodiment. The terminal determination processing device 1 starts the terminal determination process of FIG. 2 when a subframe specified by a predetermined rule among downlink subframes. For example, the terminal determination processing device 1 starts the terminal determination process of FIG. 2 at regular subframe intervals.

(Step S1) The terminal determination processing device 1 determines a determination target terminal. For example, the terminal determination processing device 1 sets all terminals connected to its own pico base station as a determination target. The terminal determination processing device 1 performs the subsequent steps S2 to S11 for each terminal to be determined. Hereinafter, the process for one terminal (determination target terminal) among the determination target terminals will be described.

(Step S2) The terminal determination processing device 1 sets as an initial value whether the determination target terminal is the A terminal or the B terminal. Specifically, the previous determination result (A terminal or B terminal) for the determination target terminal is set to an initial value. However, if this is the first determination, an initial value is set based on the MR fed back from the determination target terminal. Since this MR has information on the reception strength of the reference signal received from the neighboring base station of the determination target terminal, the terminal determination processing device 1 determines the initial value of the determination target terminal based on the reception strength information. Set.

(Step S3) If the initial value set in step S2 is the B terminal, the process proceeds to step S4. If the initial value is the A terminal, the process proceeds to step S9.

(Step S4) The terminal determination processing device 1 compares the W-SINR fed back from the determination target terminal with the B-terminal W-SINR threshold. The terminal B W-SINR threshold is held in the terminal determination processing device 1 in advance. As a result of this comparison, if W-SINR is greater than or equal to the B terminal W-SINR threshold, the process proceeds to step S5, and if it is less than the B terminal W-SINR threshold, the process proceeds to step S6.

(Step S5) The terminal determination processing device 1 determines that the determination target terminal is the B terminal. Thereafter, the process of FIG. 2 is terminated.

(Step S6) The terminal determination processing device 1 performs SINR difference value calculation processing using W-SINR and S-SINR fed back from the determination target terminal.

  Here, the details of the SINR difference value calculation process in step S6 will be described. A subframe whose subframe identification number (subframe ID) is n is denoted as subframe n. Let subframe m be the subframe that is the execution timing of the terminal determination processing this time. Also, the subframe that has received the latest RI is defined as subframe n0. Also, a subframe in which RI is received immediately before RI received in subframe n0 is defined as subframe n1. The magnitude relationship between these subframe IDs “m, n0, n1” is “n1 <n0 ≦ m”. A subframe with a smaller subframe ID is a subframe earlier in time.

The CSI fed back from the determination target terminal has the following information.
(1) When RI is 1.
・ W-SINR of codeword # 1
-S-SINR of codeword # 1 (exists for each subband)
(2) When RI is 2.
・ W-SINR of codeword # 1
-S-SINR of codeword # 1 (exists for each subband)
・ W-SINR of codeword # 2
-S-SINR of codeword # 2 (exists for each subband)

  First, a method for selecting W-SINR and S-SINR used for SINR difference calculation processing will be described. In this embodiment, W-SINR and S-SINR of codeword # 1 are used regardless of the value of RI. As for W-SINR, the latest W-SINR is used among W-SINRs received in a range from subframe n0 to subframe m (including subframe n0 and subframe m). Regarding S-SINR, the latest S-SINR is used for each subband among S-SINRs received in the range from subframe n0 to subframe m (including subframe n0 and subframe m).

  However, if W-SINR or S-SINR is not received in the range from subframe n0 to subframe m (including subframe n0 and subframe m), the section using W-SINR and S-SINR Is changed to a range from subframe n1 to subframe “n0−1” (including subframe n1 and subframe “n0−1”). Therefore, in this case, W-SINR and S-SINR received in the range from subframe n0 to subframe m (including subframe n0 and subframe m) are not used.

  Next, a method for performing SINR difference calculation processing using W-SINR and S-SINR determined to be used for SINR difference calculation processing will be described. There is only one W-SINR and S-SINR for each subband. First, the difference between W-SINR and S-SINR is calculated for each subband. Since the units of W-SINR and S-SINR are decibels, the absolute value of the difference between W-SINR and S-SINR is calculated. This absolute value is calculated by the number of subbands for which S-SINR is obtained. Next, the calculated absolute value is statistically processed to calculate one representative value (hereinafter referred to as SINR difference value). As the statistical processing method, any one of a method using the maximum value as a representative value, a method using the average value as a representative value, and a method using the median value as a representative value may be used. The above is the description of the SINR difference value calculation process in step S6.

Returning to FIG.
(Step S7) The terminal determination processing device 1 compares the SINR difference value calculated in Step S6 with the SINR difference value threshold for the B terminal. The SINR difference value threshold for the B terminal is held in the terminal determination processing device 1 in advance. As a result of the comparison, if the SINR difference value is equal to or greater than the B terminal SINR difference value threshold value, the process proceeds to step S5. If the SINR difference value is less than the B terminal SINR difference value threshold value, the process proceeds to step S8.

(Step S8) The terminal determination processing apparatus 1 determines that the determination target terminal is the A terminal. Thereafter, the process of FIG. 2 is terminated.

(Step S9) The terminal determination processing device 1 compares the W-SINR fed back from the determination target terminal with the W-SINR threshold for the A terminal. The A-terminal W-SINR threshold is stored in the terminal determination processing device 1 in advance. As a result of the comparison, if W-SINR is equal to or greater than the A-terminal W-SINR threshold, the process proceeds to step S5, and if it is less than the A-terminal W-SINR threshold, the process proceeds to step S10.

(Step S10) The terminal determination processing device 1 performs SINR difference value calculation processing using W-SINR and S-SINR fed back from the determination target terminal. This SINR difference value calculation process is the same as step S6.

(Step S11) The terminal determination processing device 1 compares the SINR difference value calculated in Step S10 with the SINR difference value threshold for A terminal. The terminal A SINR difference value threshold is stored in the terminal determination processing device 1 in advance. As a result of this comparison, if the SINR difference value is greater than or equal to the A terminal SINR difference value threshold value, the process proceeds to step S5. If the SINR difference value is less than the A terminal SINR difference value threshold value, the process proceeds to step S8.

  According to the present embodiment, when W-SINR is equal to or greater than a threshold, it is determined as a B terminal. FIG. 3 shows an example of the relationship between geometry and W-SINR. The geometry is a SINR obtained by averaging instantaneous fluctuations in a time direction and a frequency direction for a long time, and is called a geometry because it is determined from the positional relationship between the base station and the terminal. The geometry is equal to SINR calculated from the reference signal received power included in MR, and is equal to the long-term average value of W-SINR. According to equation (1), the terminal connects to the base station that gives the maximum reference signal reception power, which is the same as connecting to the base station that gives the maximum geometry.

  In the example of FIG. 3, the geometry is lower than the required SINR of the downlink control channel. Therefore, according to the geometry, the terminal having the geometry of the example of FIG. 3 is determined as a target to avoid radio wave interference from the macro base station as the A terminal. However, even when the geometry is lower than the required SINR as in the example of FIG. 3, there is a moment when the W-SINR exceeds the required SINR because the radio quality varies in units of several milliseconds. Therefore, in this embodiment, in order to determine the timing when W-SINR exceeds the required SINR, W-SINR is determined as a threshold value, and determined as a B terminal according to the determination result. As a result, the terminal can be determined following changes in the surrounding environment of the terminal and changes in instantaneous fluctuations accompanying movement of the terminal.

  Also, the threshold value of W-SINR can be made different depending on whether the initial value is the A terminal or the B terminal. As a result, the W-SINR reference for the B terminal can be changed according to the initial value. For example, by setting “W-SINR threshold for A terminal> W-SINR threshold for B terminal”, the determination result of the previous terminal determination process or the initial value based on MR is A terminal and time division multiplexing Since the threshold value for the B terminal is higher for a terminal that is a target for avoiding radio wave interference from the macro base station by the type interference control technology, it is possible to easily ensure communication quality.

  Further, according to the present embodiment, even if W-SINR is less than the threshold value, if the SINR difference value is greater than or equal to the threshold value, it is determined as the B terminal. FIG. 4 shows an example of the relationship between W-SINR and S-SINR. As illustrated in FIG. 4, the radio wave propagation path has frequency selectivity. Therefore, even for the same W-SINR, the SINR value and its distribution are different for each subband.

  For example, in LTE, downlink control channels are distributed in the frequency direction with the aim of acquiring frequency diversity gain. Therefore, even with the same W-SINR, a radio link with strong frequency selectivity is more likely to receive a downlink control channel. Therefore, in the present embodiment, the SINR difference value is determined as a threshold value in order to determine whether the radio link has strong frequency selectivity, and it is determined whether the terminal is an A terminal or a B terminal according to the determination result. Yes. As a result, a radio link terminal that has a high frequency selectivity and can expect a constant frequency diversity gain can be a B terminal. On the other hand, a radio link terminal that has low frequency selectivity and cannot be expected to have a constant frequency diversity gain is designated as A terminal, and can be targeted for avoiding radio wave interference from a macro base station by time division multiplexing interference control technology.

  Further, the threshold value of the SINR difference value can be made different depending on whether the initial value is the A terminal or the B terminal. Thereby, according to the initial value, the SINR difference value reference for the A terminal or the B terminal can be changed. For example, by setting “SINR difference value threshold for A terminal> SINR difference value threshold for B terminal”, the determination result of the previous terminal determination process or the initial value based on MR is A terminal and time division multiplexing Since the threshold value for the B terminal is higher for a terminal that is a target for avoiding radio wave interference from the macro base station by the type interference control technology, it is possible to easily ensure communication quality.

  Note that the timing for starting the terminal determination process in FIG. 2 is preferably set to a different period, for example, because the surrounding environment of the terminal and the moving speed of the terminal differ between the highway and the residential area.

  In addition, by using the previous determination result or the initial value determined based on MR as the initial value of the initial setting in step S2, the tolerance to malfunctioning when the CSI measurement is poor at the terminal is enhanced. be able to.

  In addition, in the SINR difference value calculation process in step S6, the accuracy of estimating the degree of frequency selectivity can be improved by performing statistical processing using only CSI with high freshness.

As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, the specific structure is not restricted to this embodiment, The design change etc. of the range which does not deviate from the summary of this invention are included.
For example, the W-SINR threshold determination in steps S4 and S9 may be omitted. In this case, if the SINR difference value is greater than or equal to the threshold value, it is determined as the B terminal, and if the SINR difference value is less than the threshold value, it is determined as the A terminal. As a result, the frequency diversity effect relating to the determination target terminal is determined, and when the constant frequency diversity effect is obtained, the determination target terminal is determined as the second terminal, and the determination is made when the constant frequency diversity effect cannot be obtained. It is realized that the target terminal is determined as the first terminal.

  In addition, in the initial setting in step S2 of FIG. 2, when this is the first determination, the initial value may be uniformly set as the A terminal. In this case, MR is not necessary.

  Further, in the initial setting in step S2 of FIG. 2, the initial value may be uniformly the A terminal, or only the initial value determined based on MR may be used. In this case, it is not necessary to hold the previous determination result.

2 is recorded on a computer-readable recording medium, and the program recorded on the recording medium is read into a computer system and executed, whereby terminal determination processing is performed. You may go. Here, the “computer system” may include an OS and hardware such as peripheral devices.
“Computer-readable recording medium” refers to a flexible disk, a magneto-optical disk, a ROM, a writable nonvolatile memory such as a flash memory, a portable medium such as a DVD (Digital Versatile Disk), and a built-in computer system. A storage device such as a hard disk.

Further, the “computer-readable recording medium” means a volatile memory (for example, DRAM (Dynamic DRAM) in a computer system that becomes a server or a client when a program is transmitted through a network such as the Internet or a communication line such as a telephone line. Random Access Memory)), etc., which hold programs for a certain period of time.
The program may be transmitted from a computer system storing the program in a storage device or the like to another computer system via a transmission medium or by a transmission wave in the transmission medium. Here, the “transmission medium” for transmitting the program refers to a medium having a function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line.
The program may be for realizing a part of the functions described above. Furthermore, what can implement | achieve the function mentioned above in combination with the program already recorded on the computer system, and what is called a difference file (difference program) may be sufficient.

DESCRIPTION OF SYMBOLS 1 ... Terminal determination processing apparatus (1st determination part, 2nd determination part, difference calculation part), 2 ... Radio packet scheduler part, 100 ... Macro base station, 200 ... Pico base station

Claims (11)

In a base station apparatus that avoids radio wave interference from an interfering station for downlink communication by time division multiplexing interference control technology ,
And determining the terminal determination processor first terminal and a second terminal other than the first terminal is a subject to avoid the division multiplexing interference control techniques when the radio wave interference,
A wireless packet scheduler unit,
The terminal determination processing device includes a first determination unit that determines a difference between a downlink communication quality in a wideband and a downlink communication quality in a subband for a determination target terminal, and the difference There is determined that the second terminal of the terminal to be determined if they meet the criteria, the determination target terminal when the difference does not meet the criteria determined to be the first terminal,
The radio packet scheduler unit performs radio packet scheduling for a second terminal at a timing when the interfering station transmits radio waves according to a determination result of the terminal determination processing device, and the interfering station transmits radio waves In the timing not to perform radio packet scheduling for terminals including the first terminal,
A base station apparatus . A terminal determination processing device that determines a first terminal that is a target for avoiding radio wave interference from an interfering station for downlink communication by time division multiplexing interference control technology and a second terminal other than the first terminal And
A first determination unit that determines a threshold value of a difference between downlink communication quality in a wideband and downlink communication quality in a subband related to a determination target terminal;
When the difference satisfies the criterion, the terminal to be determined is determined to be the second terminal,
A terminal determination processing device that determines a terminal to be determined to be a first terminal when the difference does not satisfy a standard,
A second determination unit configured to determine a threshold of downlink communication quality in a wideband related to a determination target terminal;
When the downlink communication quality in the wideband meets the standard, and when the difference satisfies the standard even if the downlink communication quality in the wideband does not meet the standard, Determine that the terminal is a second terminal,
When the downlink communication quality in the wideband does not satisfy the standard, and the difference does not satisfy the standard, the terminal to be determined is determined to be the first terminal.
The terminal determination processing apparatus characterized by the above.   Depending on the previous determination result regarding the determination target terminal or the determination result with the first terminal or the second terminal based on the MR (Measurement Report) fed back from the determination target terminal, the threshold determination The terminal determination processing apparatus according to claim 2, wherein different threshold values are used. The difference is calculated using the latest information of wideband communication quality information representing downlink communication quality in the wideband and the latest information of subband communication quality information representing downlink communication quality for each subband. The terminal determination processing apparatus according to claim 2, further comprising a difference calculation unit. The first terminal and the timing for starting the process of determining the second terminal is a change or cycle the movement speed is different at different locations of the terminals of the environment surrounding the terminal, we claim 2, wherein 4 The terminal determination processing device according to any one of the above. Said information representing the communication quality of the downlink Wideband are wideband CQI, information representing the communication quality of the downlink at the sub-band is a sub-band CQI, it claims 2, wherein the 5 The terminal determination processing device according to any one of the above. In a base station apparatus that avoids radio wave interference from an interfering station for downlink communication by time division multiplexing interference control technology ,
And determining the terminal decision processing device first terminal and a second terminal of the other first terminal that is the subject to avoid the division multiplexing interference control techniques when the radio wave interference,
A wireless packet scheduler unit,
The terminal determining processing apparatus, information on the determination target terminal determines whether the frequency selectivity in a strong circumstances, determine the terminal to be determined and the second terminal when the frequency selectivity is a strong situation and, when the frequency selectivity is weak situation determines the terminal to be determined and the first terminal,
The radio packet scheduler unit performs radio packet scheduling for a second terminal at a timing when the interfering station transmits radio waves according to a determination result of the terminal determination processing device, and the interfering station transmits radio waves In the timing not to perform radio packet scheduling for terminals including the first terminal,
A base station apparatus . A terminal determination method for a base station apparatus that avoids radio wave interference from an interfering station for downlink communication by time division multiplexing interference control technology,
A terminal determination step of determining a first terminal that is a target for avoiding the radio wave interference by time division multiplexing interference control technology and a second terminal other than the first terminal;
Radio packet scheduling step,
The terminal determination step performs threshold determination on the difference between the downlink communication quality in the wideband and the downlink communication quality in the subband regarding the terminal to be determined, and the difference satisfies a criterion the determination target terminal determined to be the second terminal, determines the terminal to be determined to be the first terminal if the difference does not meet the criteria,
The radio packet scheduling step performs radio packet scheduling for the second terminal at a timing when the interfering station transmits radio waves according to the determination result of the terminal determining step, and the interfering station does not transmit radio waves At the timing, radio packet scheduling is performed for terminals including the first terminal,
A terminal determination method characterized by the above. A terminal determination method for determining a first terminal that is a target for avoiding radio wave interference from an interfering station for downlink communication by a time division multiplexing interference control technique and a second terminal other than the first terminal. Yes,
For the determination target terminal, the threshold value is determined for the difference between the downlink communication quality in the wideband and the downlink communication quality in the subband,
When the difference satisfies the criterion, the terminal to be determined is determined to be the second terminal,
A terminal determination method for determining that a terminal to be determined to be a first terminal when the difference does not satisfy a criterion,
Threshold determination of downlink communication quality in wideband related to the terminal to be determined,
When the downlink communication quality in the wideband meets the standard, and when the difference satisfies the standard even if the downlink communication quality in the wideband does not meet the standard, Determine that the terminal is a second terminal,
When the downlink communication quality in the wideband does not satisfy the standard, and the difference does not satisfy the standard, the terminal to be determined is determined to be the first terminal.
A terminal determination method characterized by the above. In a computer of a base station apparatus that avoids radio wave interference from an interfering station for downlink communication by time division multiplexing interference control technology ,
A terminal determination step of determining a first terminal that is a target for avoiding the radio wave interference by time division multiplexing interference control technology and a second terminal other than the first terminal ;
A computer program for executing a radio packet scheduling step ,
The terminal determination step performs threshold determination on the difference between the downlink communication quality in the wideband and the downlink communication quality in the subband regarding the terminal to be determined, and the difference satisfies a criterion the determination target terminal determined to be the second terminal, determines the terminal to be determined to be the first terminal if the difference does not meet the criteria,
The radio packet scheduling step performs radio packet scheduling for the second terminal at a timing when the interfering station transmits radio waves according to the determination result of the terminal determining step, and the interfering station does not transmit radio waves At the timing, radio packet scheduling is performed for terminals including the first terminal,
A computer program characterized by the above. A terminal determination process for determining a first terminal that is a target for avoiding radio wave interference from an interfering station for downlink communication by time division multiplexing interference control technology and a second terminal other than the first terminal. A computer program for performing
For the determination target terminal, the threshold value is determined for the difference between the downlink communication quality in the wideband and the downlink communication quality in the subband,
When the difference satisfies the criterion, the terminal to be determined is determined to be the second terminal,
Determining that the terminal to be determined to be the first terminal if the difference does not meet the criteria; and
Threshold determination of downlink communication quality in wideband related to the terminal to be determined,
When the downlink communication quality in the wideband meets the standard, and when the difference satisfies the standard even if the downlink communication quality in the wideband does not meet the standard, Determine that the terminal is a second terminal,
Determining that the terminal to be determined is the first terminal when the downlink communication quality in the wideband does not satisfy the standard and the difference does not satisfy the standard; and
A computer program for causing a computer to execute.

Images