KR101653927B1 - Method and Apparatus for Power Headroom Report-based Uplink Power Control in 3GPP LTE-A HetNet - Google Patents

Abstract

A power headroom based uplink power control method and apparatus are presented. The power headroom-based uplink power control method proposed by the present invention includes initializing a user's initial network connection and closed loop-power control parameters, using a power headroom report based power efficiency resource allocation, Setting open loop-power control parameters, setting transmission power of the user using the open loop-power control parameter setting procedure and transmitting data, transmitting the data to the user according to a predetermined criterion Determining a transmission power control command parameter, reporting the power headroom to the user, and determining a dependent parameter of the modulation and coding scheme depending on whether the user is reporting a power headroom.

Description

TECHNICAL FIELD The present invention relates to a power headroom based uplink power control method and apparatus for a 3GPP LTE-A heterogeneous network environment,

The present invention relates to a power and spectral efficiency uplink power control method and apparatus for improving cell capacity in a 3GPP LTE-A HetNet environment.

In the 3GPP LTE-A uplink, orthogonality provided by single carrier-frequency division multiple access (SC-FDMA) eliminates intra-cell interference.

The 3GPP LTE-A system uses an aggressive frequency reuse scheme to maximize spectral efficiency, so that all cells in the network use the same frequency band.

1 is a diagram illustrating a HetNet deployment scenario according to an embodiment of the present invention.

In the HetNet (heterogeneous network) environment of 3GPP LTE-A, low-power, short-range and low-cost base stations, called femto eNBs, are installed at an efficient cost to meet consumers' increasing traffic data needs.

The aggressive frequency reuse technique causes inter-cell interference which may cause capacity degradation. Therefore, the 3GPP LTE-A uplink can use FPC (fractional power control) to provide the appropriate transmit power to the required signal to achieve the required quality, and can be used by neighboring cell users using the same frequency band The inter-cell interference can be minimized.

Is determined in the 3GPP LTE-A FPC according to the following formula of the UE transmission power.

Here, P _tx is the UE transmission power, P _max in a subframe i is the maximum allowable UE transmission power defined as 23dBm, M is the physical resource block allocated to the UE: represents the number of (PRBs physical resource block), wherein If more PRBs are allocated to the UE, more UE transmit power is needed. And, P ₀ is the target received power, α is a path loss competition factor, PL is a path loss between the user and the serving base station the user, Δ _MCS is the modulation and coding scheme (MCS: modulation and coding scheme) dependent factor, f (i) represents a transmit power control (TPC) command.

Open-loop power control (OL-PC) controls power spectral density (PSD), which is power allocated to each PRB. The PSD at this time can be expressed by the following equation.

The jeokryeok received target P ₀ are each cell as the expression to - can be calculated in the performance and UE- performance value sum of P and P _{0_CELL 0_UE.}

P ₀ is transmitted to the UE using System Information Block 2 (SIB 2), and its transmission period is selected from {8, 16, 32, 64, 128, 256, 512} radio frames . In the embodiment of the present invention, eight radio frames (80 ms) are selected as SIB2 transmission periods for various P ₀ changes.

The uplink transmission power is set based on the downlink path loss estimate for compensation for the uplink path loss PL.

The α value determines how much path loss is compensated for, and the α value can be selected from {0, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1}.

Closed-loop power control (CL-PC) supports the UE to control power. [Delta] _MCS is a value determined by the transmission format selected by the base station for uplink transmission, and can be calculated as follows.

Bit per resource element (BPRE) is calculated as O _CQI / N _RE where O _CQI is the number of CQI bits and N _RE is the number of resource elements (REs). K _s is given by deltaMCS-Enabled provided by 1.25 higher rails.

Is provided according to the MCS level difference by the table in [36.213].

f (i) is a transmit power control (TPC) command sent to the UE by the base station to increase or decrease the transmit power, and may be expressed by the following equation based on the comparison of the received SINR and target SINR .

Here, i denotes an i-th sub-frame, and indicates a delay of four sub-frames from the sub-frame i. δ _PUSCH is the TPC command value defined in the table below.

The UE reports a parameter called a power headroom (PH) calculated using the following equation.

The UE transmit power in 3GPP LTE-A has a maximum limit of 23dBm, so uplink power control can also maximize the battery life of the mobile terminal. The ultimate goal is to meet the growing demand for data traffic in 5G systems.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method and apparatus for solving an unexpected femtocell allocation according to an aggressive frequency reuse technique for generating inter-cell uplink interference in a network causing a capacity drop . Since the inter-cell interference problem becomes more severe as the network becomes denser due to unexpected small cells, a scheme for designing power and spectral efficiency uplink power control schemes to provide capacity improvement in networks with high uplink interference I suggest. The UE transmit power in 3GPP LTE-A has a maximum limit of 23 dBm and therefore allocating a larger number of PRBs than allowed by the UE may reduce the power spectral density resulting in power and spectral efficiency.

In one aspect, a power headroom based uplink power control method proposed by the present invention includes initializing a user's initial network connection and closed loop power control parameters, using power headroom report based power efficiency resource allocation, Assigning a physical resource block to the user, setting open loop-power control parameters, setting the transmit power of the user using the open loop-power control parameter setting procedure and transmitting the data, Determining a transmission power control command parameter to be transmitted to the user, reporting the power headroom to the user, and determining a dependent parameter of the modulation and coding scheme depending on whether the user has a power headroom report can do.

Wherein allocating a physical resource block to the user by using the power headroom report based power efficiency resource allocation comprises: determining whether a current user has received a power headroom report; if the current user has received the power headroom report Calculating a number of physical resource blocks that can be allocated at the maximum, determining whether the order of the current user is the last user, determining whether the order of the current user is the last user, And allocating a physical resource block to the current user.

Setting the open loop-power control parameters, setting the transmit power of the user using the open loop-power control parameter setting procedure, and transmitting data, wherein the setting of the open loop- Interference and SINR can be averaged.

Wherein the step of setting the transmission power of the user using the open loop-power control parameter setting procedure and transmitting the data comprises: calculating a cell performance using the averaged interference and SINR; The transmission power of the user can be set.

The step of determining a transmit power control command parameter to be transmitted to the user according to the predetermined criterion comprises calculating a difference between a target SINR and a received SINR to determine a transmit power control command parameter to be transmitted to the user according to the predetermined criterion And transmit a positive transmit power control command value to the user to increase the transmit power if the received SINR does not meet the target SINR.

The step of determining the dependent parameter of the modulation and coding scheme according to whether or not the user reports the power headroom determines the level of the modulation and coding scheme according to whether the user reports the power headroom based on the received SINR And may transmit an offset to the user.

In another aspect, the power headroom based uplink power control apparatus proposed by the present invention includes an initialization unit for initializing a user's initial network connection and closed loop-power control parameters, a power headroom report based power efficiency resource allocation An open loop power control parameter setting step of setting an open loop power control parameter setting process to set a transmission power of the user and a power headroom of the user, A transmission unit for transmitting the data of the transmission power of the set user and reporting the power headroom to the user, a transmission unit for transmitting the data of the power headroom to the user according to a predetermined criterion, A transmission power control command parameter to be transmitted to the user Generating a command for determining may include a.

Wherein the allocator determines whether a current user has received a power headroom report and calculates a maximum number of allocatable physical resource blocks when the current user receives the power headroom report, And if the current user's order is the last user, the physical resource block may be allocated to the current user according to the number of physical resource blocks of the current user.

The variable setting and calculation unit may set the open loop-power control parameters to average the interference and the SINR to calculate the cell performance, and to set the transmission power of the user using the cell performance.

The variable setting and calculation unit may determine the level of the modulation and coding scheme depending on whether the user's power headroom is reported based on the received SINR.

Wherein the command generator calculates a difference between a target SINR and a received SINR to determine a transmission power control command parameter to be transmitted to the user according to the predetermined criterion, and when the received SINR does not satisfy the target SINR, And may transmit a positive transmit power control command value to the user to increase transmit power.

According to embodiments of the present invention, by allocating UEs whose UE power has a number of allowable PRBs, a reduction in PSD that affects power efficiency can be avoided. By allocating excess PRBs to the power-capable UE, the spectrum resource can be utilized more efficiently. In addition, the OL-PC application can determine an appropriate value of the target received power of the macro and femtocells by setting the open-loop parameters based on the average received SINR and the uplink interference generated by neighboring cells. And, by using the CL-PC, the fading effect can be compensated for to meet the target SINR determined by the OL-PC for the UE uplink SINR.

1 is a diagram illustrating a HetNet deployment scenario according to an embodiment of the present invention.
2 is a flowchart illustrating a PHR-UPC method according to an embodiment of the present invention.
3 is a flowchart illustrating a PHR-PERA method according to an embodiment of the present invention.
4 is a diagram for explaining a process of applying an OL-PC according to an embodiment of the present invention.
5 is a diagram for explaining a process of determining Δ _mcs according to an embodiment of the present invention.
6 is a diagram for explaining a process of determining a TPC command value according to an embodiment of the present invention.
7 is a diagram showing a configuration of a PHR-UPC apparatus according to an embodiment of the present invention.

In the present invention, a power headroom report defined in 3GPP LTE-A performance is used to perform the power and spectrum efficiency resource allocation for controlling the total transmission power of a user (UE). The interference and SINR caused in the PRB for allocating an appropriate amount of transmission power to each physical resource block (PRB) allocated to the UE can be averaged over the open loop parameter update period. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a flowchart illustrating a PHR-UPC method according to an embodiment of the present invention.

A power headroom based uplink power control (PHR-UPC) method includes initializing (210) a user's initial network connection and closed loop-power control parameters, using power headroom report based power efficiency resource allocation A step of allocating physical resource blocks (220), setting open loop-power control parameters, setting the transmit power of the user using the open loop-power control parameter setting procedure and transmitting data (231, 232 Determining (250) a transmission power control command parameter to be transmitted to the user according to a predetermined criterion, reporting (260) the power headroom to the user, modulating (260) And determining (240) dependent parameters of the coding scheme.

In step 210, initial network connection and closed loop-power control parameters of the user (UE) may be initialized.

The UE may be connected to a closed loop-power control (CL-PC) parameter and network initialized to zero. In other words, the UE may be connected to a Radio Resource Control (RRC), initialize the dependent parameter? _MCS of the modulation and coding scheme, and initialize the transmit power control command parameters.

In step 220, a physical resource block may be allocated to the user by using power headroom report based power efficient resource allocation.

Step 220 includes determining 320 whether a current user has received a power headroom report, calculating 32 the maximum number of physical resource blocks that can be allocated when the current user receives the power headroom report Determining whether the current user's order is the last user, determining whether the current user's order is the last user, allocating a physical resource block to the current user according to the number of physical resource blocks owned by the current user, (Steps 331, 340, 350, and 360). Will be described in more detail with reference to FIG.

3 is a flowchart illustrating a PHR-PERA method according to an embodiment of the present invention.

When assigning a PRB to the user by using Power Headroom Report based Power Efficiency Resource Allocation (PHR-PERA), the base station uses the conventional LTE-A uplink scheduling algorithm To pre-allocate (310) a user with M _initial numbers of PRBs.

Then, it is determined whether the i-th user UE (i) has received the power headroom report (320). If the i-th user UE (i) has not received the power headroom report, M _initial is assigned (322). On the other hand, when the i-th user UE (i) receives the power headroom report, the UE transmission power in the 3GPP LTE-A has a maximum limit of 23 dBm, and therefore the base station determines the M _PHR , which is the number of PRBs (321). This is the number of PRBs that are UE power states that can be accommodated by using the power headroom report to avoid a decrease in the power spectral density. When the base station (BS) receives the PHR, the UE transmit power in the previous subframe can be calculated as follows.

From here,

Is the number of PRBs allocated to the UE in the previous subframe. PSD _tx can be expressed by the following equation.

The UE transmit power in the current subframe is determined in consideration of the following equation.

Here, M _PHR is the number of UE power capacities PRBs that can be accommodated. The M _PHR can be calculated by the following equation.

When the UE does not have a PHR, the base station assigns M _initial to the UE (322). After calculating the number M _PHR of the maximum allocatable physical resource blocks (321), it is determined whether the order of the current user is the last user (330). If the current user's order is the last user, the physical resource block is allocated to the current user according to the number of physical resource blocks of the current user.

When M _PHR equals the number of M _initial , M _initial is assigned to UE (331). When M _initial number is greater than M _PHR , M _PHR is allocated to the UE and ( M _initial - M _PHR ) is collected (340) as excess PRB. Then, M _add is assigned to the user having M _PHR greater than M _initial (350). Finally, M _initial + M _add is assigned (360).

Next, in steps 231 and 232, open loop-power control parameters are set and the transmission power of the user is set using the open loop-power control parameter setting procedure and data is transmitted. This will be described in more detail with reference to FIG.

4 is a diagram for explaining a process of applying an OL-PC according to an embodiment of the present invention.

The path loss compensation factor a is set, the path loss between the UE and the serving base station of the UE, and the path loss between the UE and the strongest neighbor base station are measured as P ^servinig and P ^{strongest_neighbor} , respectively.

P ₀ is determined by using the adaptive OL-PC parameter determination procedure. The received SINR and the received interference plus noise 221 are averaged as SINR _av and IN _av , respectively, using the following equation at a base station over a period of 80 ms (410).

Then, it is determined whether i mod 80 = 0 (420). If i mod 80 = 0, the process is repeated from the averaging step (410). i mod 80 = 0, to substitute _av IN to the IN, and substituting the SINR _av the SINR ₀ (421).

Then, P ₀ is calculated 430 using the cell performance P _{0_CELL} and the UE performance P _{0_UE} . The cell performance _{P0_CELL} is calculated using the averaged received SINR and interference.

Then, the UE-performance _{P0_UE} is calculated using the following equation.

If the strongest neighbor path loss is large enough, the UE may increase the power by setting the target SINR higher using the positive offset of _{P0_UE} , otherwise the UE may use the negative offset of _{P0_UE} to increase the target SINR The power can be reduced.

In step 240, dependent parameters of the modulation and coding scheme may be determined according to whether the user is reporting a power headroom. The level of the modulation and coding scheme may be determined according to whether the user's power headroom is reported based on the received SINR, and the offset may be transmitted to the user. This will be described in more detail with reference to FIG.

5 is a diagram for explaining a process of determining a dependent parameter? _Mcs of a modulation and coding scheme (MCS) according to an embodiment of the present invention.

In determining the MCS dependent parameter [Delta] _MCS , the base station determines the MCS level based on the received SINR.

First, it is determined whether the UE receives the PHR (510). When the UE receives the PHR, it determines whether the UE receives the negative PHR (520). If the UE receives a negative PHR, the MCS level I _CQI may be reduced by one (521). The negative PHR means that the UE transmission power is maximally limited. Therefore, the base station transmits a negative offset to the UE to reduce the transmission power of the UE.

If the UE does not receive a negative PHR, it determines whether PHR is 0 (522). If the UE does not receive the PHR or if the PHR is 0, the MCS level I _CQI is maintained (531). In other words, if no power headroom is reported, or if the reported power headroom value is zero, there is no change in the selected MCS level based on the received SINR.

On the other hand, when the UE receives a positive PHR, the MCS level I _CQI selected by default based on the received SINR is incremented by one (532). The BS can consider that it is possible to increase its transmission power for the UE.

Then, if an appropriate MCS level for PUSCH transmission is selected, the _MCS is calculated (540). In other words, the following equation is used to calculate? _MCS based on the MCS level I _CQI .

In step 250, a transmit power control command parameter to be transmitted to the user may be determined according to a predetermined criterion. At this time, a difference between the target SINR and the received SINR is calculated to determine a transmission power control command parameter to be transmitted to the user according to the predetermined criterion. If the received SINR does not satisfy the target SINR, the mobile station transmits a positive transmission power control command value to the user to increase the transmission power. Will be described in more detail with reference to FIG.

FIG. 6 is a diagram for explaining a process of determining a TPC command value according to an embodiment of the present invention. Referring to FIG.

The step of determining the TPC command parameter f (i) first calculates (610) a difference ΔSINR between the target SINR and the received SINR.

The TPC value is generated according to the following criterion.

For example, it is determined whether ΔSINR is less than or equal to -1 (620). If? SINR is less than or equal to -1,? _PUSCH transmits -1 (621).

It is determined whether ΔSINR is less than or equal to 1 (630). If? SINR is greater than -1 and less than or equal to 1,? _PUSCH transmits 0 (631).

It is determined whether ΔSINR is less than or equal to 5 (640). If? SINR is greater than 1 and less than or equal to 5,? _PUSCH transmits 1 (641).

If? SINR is greater than 5,? _PUSCH transmits 3 (650).

Then, in step 260, the user can report the power headroom.

If the received SINR does not meet the target SINR, the base station may send a positive TPC command value to the UE to increase the transmit power. Otherwise, conversely, it may send a negative TPC command value to the UE to reduce the transmit power.

7 is a diagram showing a configuration of a PHR-UPC apparatus according to an embodiment of the present invention.

The power headroom based uplink power control (PHR-UPC) apparatus includes an initialization unit 710, an allocation unit 720, a variable setting and calculation unit 730, a transmission unit 740, and an instruction generation unit 750 can do.

The initialization unit 710 may initialize the user's initial network connection and closed loop-power control parameters.

The allocator 720 may allocate a physical resource block to the user by using power headroom report based power efficient resource allocation. The allocating unit 720 determines whether the current user has received the power headroom report and calculates the maximum number of allocatable physical resource blocks when the current user receives the power headroom report. If the order of the current user is the last user, the physical resource block may be allocated to the current user according to the number of physical resource blocks owned by the current user.

The variable setting and calculation unit 730 may set the open loop-power control parameters and set the transmission power of the user using the open loop-power control parameter setting procedure. And determine dependent parameters of the modulation and coding scheme depending on whether the user is reporting a power headroom. The variable setting and calculation unit 730 may calculate the cell performance by averaging interference and SINR and setting the open loop-power control parameters, and may set the transmission power of the user using the cell performance. Then, based on the received SINR, the level of the modulation and coding technique can be determined according to whether the user's power headroom is reported.

The transmitting unit 740 transmits data of the set transmission power of the user, and reports the power headroom to the user.

The command generator 750 may determine a transmission power control command parameter to be transmitted to the user according to a predetermined criterion. The command generator 750 calculates the difference between the target SINR and the received SINR to determine a transmission power control command parameter to be transmitted to the user according to the predetermined criterion. If the received SINR does not satisfy the target SINR, the mobile station transmits a positive transmission power control command value to the user to increase the transmission power.

The proposed PHR-PERA effectively utilizes limited bandwidth and power resources by allocating PRBs to the UE corresponding to the UE power capability. And, OL-PC application improves the capacity of macros and femtocells by setting open-loop parameters based on average received SINR and uplink interference caused by neighboring cells. By applying the proposed uplink power control scheme, the cell capacity can be maximized in the 3GPP LTE-A HetNet environment despite the interference situation. Further, by using the OL-PC supported by the CL-PC based on the PHR and the received SINR, the UE uplink SINR can satisfy the SINR determined by the base station using the OL-PC only through compensation of the fading effect have.

The apparatus described above may be implemented as a hardware component, a software component, and / or a combination of hardware components and software components. For example, the apparatus and components described in the embodiments may be implemented within a computer system, such as, for example, a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable array (FPA) A programmable logic unit (PLU), a microprocessor, or any other device capable of executing and responding to instructions. The processing device may execute an operating system (OS) and one or more software applications running on the operating system. The processing device may also access, store, manipulate, process, and generate data in response to execution of the software. For ease of understanding, the processing apparatus may be described as being used singly, but those skilled in the art will recognize that the processing apparatus may have a plurality of processing elements and / As shown in FIG. For example, the processing unit may comprise a plurality of processors or one processor and one controller. Other processing configurations are also possible, such as a parallel processor.

The software may include a computer program, code, instructions, or a combination of one or more of the foregoing, and may be configured to configure the processing device to operate as desired or to process it collectively or collectively Device can be commanded. The software and / or data may be in the form of any type of machine, component, physical device, virtual equipment, computer storage media, or device , Or may be permanently or temporarily embodied in a transmitted signal wave. The software may be distributed over a networked computer system and stored or executed in a distributed manner. The software and data may be stored on one or more computer readable recording media.

The method according to an embodiment may be implemented in the form of a program command that can be executed through various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions to be recorded on the medium may be those specially designed and configured for the embodiments or may be available to those skilled in the art of computer software. Examples of computer-readable media include magnetic media such as hard disks, floppy disks and magnetic tape; optical media such as CD-ROMs and DVDs; magnetic media such as floppy disks; Magneto-optical media, and hardware devices specifically configured to store and execute program instructions such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine language code such as those produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the embodiments, and vice versa.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. For example, it is to be understood that the techniques described may be performed in a different order than the described methods, and / or that components of the described systems, structures, devices, circuits, Lt; / RTI > or equivalents, even if it is replaced or replaced.

Therefore, other implementations, other embodiments, and equivalents to the claims are also within the scope of the following claims.

Claims (11)

A power headroom based uplink power control method,
Initializing a user's initial network connection and closed loop-power control parameters;
Allocating a physical resource block to the user by using power headroom report based power efficient resource allocation;
Setting open loop-power control parameters, setting transmission power of the user using the open loop-power control parameter setting procedure, and transmitting data;
Determining a transmission power control command parameter to be transmitted to the user according to a predetermined criterion;
Reporting the power headroom to the user; And
Determining dependent parameters of the modulation and coding scheme depending on whether the user is reporting a power headroom
Lt; / RTI >
Wherein allocating physical resource blocks to the user by using the power headroom report based power efficient resource allocation comprises:
Determining whether a current user has received a power headroom report;
Calculating a maximum number of allocatable physical resource blocks when the current user receives the power headroom report;
Determining whether the order of the current user is the last user; And
Allocating a physical resource block to the current user according to the number of physical resource blocks of the current user if the current user's order is the last user
/ RTI > power control method based on power headroom. delete The method according to claim 1,
Setting the open loop-power control parameters, setting the transmit power of the user using the open loop-power control parameter setting procedure, and transmitting data,
Setting the open loop-power control parameters comprises averaging the interference and SINR, calculating a target received power using the averaged interference and SINR, and setting the transmit power of the user using the target received power
And a power headroom-based uplink power control method. delete The method according to claim 1,
Wherein determining the transmit power control command parameter to transmit to the user according to the predetermined criteria comprises:
Calculating a difference between a target SINR and a received SINR to determine a transmission power control command parameter to be transmitted to the user according to the predetermined criterion, and when the received SINR does not satisfy the target SINR, To transmit the positive transmission power control command value to the user,
And if the received SINR satisfies the target SINR sufficiently, the transmission power control command value is not transmitted or the transmission power control command value is not transmitted so that the transmission power is not changed so that the reception performance between users is equalized. To transmit a negative transmit power control command value
And a power headroom-based uplink power control method. The method according to claim 1,
The step of determining dependent parameters of the modulation and coding scheme, depending on whether the user is reporting a power headroom,
Determining the level of the modulation and coding scheme according to the report of the user's power headroom based on the received SINR and transmitting an offset to the user
And a power headroom-based uplink power control method. A power headroom based uplink power control apparatus,
An initialization unit for initializing a user's initial network connection and a closed loop-power control parameter;
An allocation unit for allocating a physical resource block to the user by using power headroom report based power efficiency resource allocation;
Setting open loop-power control parameters, setting the transmission power of the user using the open loop-power control parameter setting procedure, and determining a dependent parameter of the modulation and coding scheme depending on whether the user reports the power headroom A variable setting unit and a calculating unit;
A transmission unit for transmitting data of the transmission power of the set user and reporting the power headroom to the user; And
A transmission power control command parameter determining unit that determines a transmission power control command parameter to be transmitted to the user according to a predetermined criterion,
Lt; / RTI >
Wherein the allocating unit comprises:
The method comprising: determining whether a current user has received a power headroom report; calculating, when the current user receives the power headroom report, calculating the maximum number of physical resource blocks that can be allocated and determining whether the current user's order is the last user Allocating a physical resource block to the current user according to the number of physical resource blocks of the current user if the current user's order is the last user
Power headroom based uplink power control apparatus. delete 8. The method of claim 7,
Wherein the variable setting and calculation unit comprises:
The setting of the open loop-power control parameters may include calculating a target received power by averaging the interference and the SINR, and setting the transmit power of the user using the target received power
Power headroom based uplink power control apparatus. 8. The method of claim 7,
Wherein the variable setting and calculation unit comprises:
Determining the level of the modulation and coding scheme according to whether the user's power headroom is reported based on the received SINR
Power headroom based uplink power control apparatus. 8. The method of claim 7,
Wherein the command generator comprises:
Calculating a difference between a target SINR and a received SINR to determine a transmission power control command parameter to be transmitted to the user according to the predetermined criterion, and when the received SINR does not satisfy the target SINR, To transmit the positive transmission power control command value to the user,
And if the received SINR satisfies the target SINR sufficiently, the transmission power control command value is not transmitted or the transmission power control command value is not transmitted so that the transmission power is not changed so that the reception performance between users is equalized. To transmit a negative transmit power control command value
Power headroom based uplink power control apparatus.

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