Method and apparatus for supporting power backoff reporting when performing power headroom reporting in a wireless communication system

Abstract

The present disclosure relates to a communication technology and a system thereof for aggregating a 5G communication system and an IoT technology, wherein the 5G communication system is used to support a higher data transmission rate than a 4G system. The present disclosure can be applied to intelligent services based on 5G communication technology and IoT-related technologies (e.g., smart homes, smart buildings, smart cities, smart cars or connected cars, health care, digital education, retail business, security and safety-related services, etc.). A method and apparatus for receiving a PHR configuration including a threshold and a prohibition timer from a base station is provided. Whether the PHR is triggered is identified based on the PHR configuration. In the case where the PHR is triggered, the PHR is transmitted to the base station. The PHR includes a bit field indicating power backoff applied based on power management when the P field is set to 1.

Description

Technical Field

[0001] The present disclosure generally relates to operations of a terminal and a base station in a wireless communication system, and more particularly, to a method for reporting a transmit power headroom by a terminal in a wireless communication system. Background Art

[0002] In order to meet the increased demand for wireless data services since the deployment of 4G communication systems, efforts have been made to develop improved 5G or pre-5G communication systems. Therefore, 5G or pre-5G communication systems are also referred to as "beyond 4G networks" or "post-LTE systems". 5G communication systems are considered to be implemented in higher frequency (mmWave) bands (e.g., 60GHz bands) in order to achieve higher data rates. In order to reduce the propagation loss of radio waves and increase the transmission distance, beamforming, massive multiple-input multiple-output (MIMO), full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, and massive antenna technology are discussed in 5G communication systems. In addition, in 5G communication systems, improvements in system networks are being developed based on advanced small cells, cloud radio access networks (RANs), ultra-dense networks, device-to-device (D2D) communications, wireless backhaul, mobile networks, collaborative communications, coordinated multi-point (CoMP), receiving-end interference elimination, etc. In 5G systems, hybrid frequency shift keying (FSK) and quadrature amplitude modulation (QAM) modulation (FQAM) and sliding window superposition coding (SWSC) are deployed as advanced coded modulation (ACM), and filter bank multi-carrier (FBMC), non-orthogonal multiple access (NOMA) and sparse code multiple access (SCMA) are deployed as advanced access technologies.

[0003] The Internet is now developing into the Internet of Things (IoT), in which distributed entities such as things exchange and process information without human intervention. The Internet of Everything (IoE) has emerged, which is a combination of IoT technology and big data processing technology through connection with cloud servers. Technical elements such as "sensing technology", "wired / wireless communication and network infrastructure", "service interface technology" and "security technology" are required for IoT implementation, and sensor networks, machine-to-machine (M2M) communication, machine type communication (MTC), etc. have been studied recently. This IoT environment can provide intelligent Internet technology services that create new value for human life by collecting and analyzing data generated between networked things. Through the integration and combination between existing information technology (IT) and various industrial applications, IoT can be applied to various fields, including smart homes, smart buildings, smart cities, smart cars or connected cars, smart grids, health care, smart devices, and advanced medical services.

[0004] In line with this, various attempts have been made to apply 5G communication systems to IoT networks. For example, technologies such as sensor networks, MTC, and M2M communications can be implemented through beamforming, MIMO, and array antennas. The application of cloud RAN, which is the above-mentioned big data processing technology, can also be considered an example of the fusion of 5G technology and IOT technology. Summary of the invention

[0005] Technical issues

[0006] The present disclosure provides a method in which, when a terminal reports a transmit power headroom (PH) in a wireless communication system, the terminal notifies a base station that power backoff has been performed.

[0007] Solution

[0008] According to the present disclosure, the terminal can individually adjust the power headroom report caused by the occurrence of power backoff, so that when the corresponding situation occurs, the base station can be immediately notified of the corresponding fact and can perform scheduling according to the transmission power of the terminal.

[0009] According to an embodiment, a method performed by a terminal includes: receiving a power headroom report (PHR) configuration from a base station, the PHR configuration including a threshold and a prohibition timer for power management based on maximum power reduction; identifying whether the PHR is triggered based on the PHR configuration; and in the case where the PHR is triggered, transmitting the PHR to the base station, wherein the PHR includes a bit field indicating power backoff applied based on power management when the P field is set to 1.

[0010] According to an embodiment, a method performed by a base station includes: transmitting a power headroom report (PHR) configuration to a terminal, the PHR configuration including a threshold and a prohibition timer for power management based on maximum power reduction; and receiving the PHR from the terminal when the PHR is triggered, wherein the PHR is triggered based on the PHR configuration, wherein the PHR includes a bit field indicating power backoff applied based on power management when the P field is set to 1.

[0011] According to one embodiment, a terminal is provided, which includes a transceiver and a controller coupled to the transceiver. The controller is configured to receive a power headroom report (PHR) configuration from a base station, the PHR configuration including a threshold and a prohibition timer for power management based on maximum power reduction, identify whether the PHR is triggered based on the PHR configuration, and transmit the PHR to the base station if the PHR is triggered, wherein the PHR includes a bit field indicating power backoff based on power management application when the P field is set to 1. According to one embodiment, a base station is provided, which includes a transceiver and a controller coupled to the transceiver. The controller is configured to transmit a power headroom report (PHR) configuration to the terminal, the PHR configuration including a threshold and a prohibition timer for power management based on maximum power reduction, and receive the PHR from the terminal if the PHR is triggered, wherein the PHR is triggered based on the PHR configuration, wherein the PHR includes a bit field indicating power backoff based on power management application when the P field is set to 1.

[0012] Advantageous Effects of the Invention

[0013] According to the present disclosure, the terminal can individually adjust the power headroom report caused by the occurrence of power backoff, so that when the corresponding situation occurs, the base station can be immediately notified of the corresponding fact and can perform scheduling according to the transmission power of the terminal. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The above and other aspects, features and advantages of the present disclosure will become more apparent from the following description in conjunction with the accompanying drawings, in which:

[0015] Figure 1 is a diagram showing a structure of an LTE system according to an embodiment;

[0016] Figure 2 is a diagram showing a radio protocol structure in an LTE system according to an embodiment;

[0017] Figure 3 is a diagram illustrating carrier aggregation in a terminal according to an embodiment;

[0018] Figure 4 is a diagram illustrating the concept of multi-connectivity in LTE and NR according to an embodiment;

[0019] Figure 5A is a diagram showing an uplink transmission method according to an embodiment;

[0020] Figure 5B is a diagram showing a multi-entry PHR MAC CE format according to an embodiment;

[0021] Figure 5Cis a diagram showing a multi-entry PHR MAC CE format according to an embodiment;

[0022] Figure 6 is a diagram showing an operation sequence of a UE according to a method of reporting a PHR when power backoff occurs due to power control according to an embodiment;

[0023] Figure 7 is a diagram showing a block configuration of a UE in a wireless communication system according to an embodiment; and

[0024] Figure 8 is a diagram showing a structure of a base station according to an embodiment. DETAILED DESCRIPTION

[0025] Embodiments of the present disclosure are described in detail with reference to the accompanying drawings. The same or similar components may be represented by the same or similar reference numerals, even though they are shown in different drawings. Detailed descriptions of constructions or processes known in the art may be omitted to avoid obscuring the subject matter of the present disclosure.

[0026] The terms described below are defined in consideration of the functions in the present disclosure and may differ depending on the user, the user's intention or habit. Therefore, the definition of the terms should be made based on the contents of the entire specification.

[0027] In the following description, for the sake of convenience, terms used to identify access nodes, terms related to network entities, terms related to messages, terms related to interfaces between network entities, terms related to various identification information, etc. are exemplarily used. Therefore, the present disclosure is not limited to the terms used below, and other terms related to subjects with equivalent technical meanings may be used.

[0028] Here, for the convenience of description, the present disclosure will be described using terms and names defined in the 3rd Generation Partnership Project Long Term Evolution (3GPP LTE) standard, which is the latest standard among existing communication standards. However, the present disclosure is not limited by these terms and names, and can be applied to systems conforming to other standards in the same manner. In particular, the present disclosure can be applied to 3GPP NR (New Radio, the fifth generation mobile communication standard).

[0029] Figure 1 is a diagram showing a structure of an LTE system according to an embodiment.

[0030] Reference Figure 1, the wireless communication system includes a plurality of base stations 105, 110, 115 and 120, a mobility management entity (MME) 125 and a serving gateway (S-GW) 130. A user equipment (UE or terminal) 135 can access an external network through the base stations 105, 110, 115 and 120 and the S-GW 130.

[0031] The base stations 105, 110, 115, and 120 are access nodes of the cellular network and can provide wireless access to UEs connected to the network. That is, in order to serve the user's business, the base stations 105, 110, 115, and 120 can support the connection between the UE and the core network (CN) by collecting state information such as the buffer state, available transmission power state, and channel state of the UE, and perform scheduling thereof. The MME 125 is a device for performing various control functions of the UE and a mobility management function, and is connected to a plurality of base stations, and the S-GW 130 provides data bearers. The MME 125 and the S-GW 130 can also perform authentication and bearer management for the terminal connected to the network, and process packets to be transmitted to the base station, and can process packets from the base stations 105, 110, 115, and 120 or packets to be transmitted to the base stations 105, 110, 115, and 120.

[0032] Figure 2 NR system has almost the same protocol structure as LTE system.

[0033] Reference Figure 2 , the radio protocol of the LTE system is configured as Packet Data Convergence Protocol (PDCP) 205 and 240, Radio Link Control (RLC) 210 and 235, and Medium Access Control (MAC) 215 and 230 in the corresponding UE and eNB. PDCP 205 and 240 are responsible for operations such as IP header compression / reconstruction, and RLC 210 and 235 can reconfigure PDCP packet data units (PDUs) to an appropriate size.

[0034] MAC 215 and 230 are connected to multiple RLC layer devices configured in one terminal, and can perform operations of multiplexing RLC PDU with MAC PDU and demultiplexing RLC PDU with MAC PDU. Physical (PHY) layers 220 and 225 can perform the following operations: channel coding and modulating higher layer data, generating higher layer data as OFDM symbols, transmitting OFDM symbols via a radio channel, or demodulating and channel decoding OFDM symbols received via a radio channel, and transmitting OFDM symbols to a higher layer. In addition, the physical layer uses hybrid ARQ (HARQ) for additional error correction, and the receiving terminal transmits 1 bit indicating whether the packet transmitted from the transmitting terminal is received. This is called HARQ ACK / NACK information. Downlink HARQ ACK / NACK information for uplink transmission may be transmitted through a Physical Hybrid ARQ Indicator Channel (PHICH), and uplink HARQ ACK / NACK information for downlink transmission may be transmitted through a Physical Uplink Control Channel (PUCCH) or a Physical Uplink Shared Channel (PUSCH) physical channel.

[0035] A Radio Resource Control (RRC) layer exists at an upper portion of a PDCP layer of a UE and a base station, respectively, and the RRC layer may receive or transmit various configuration control messages related to access and measurement for controlling radio resources.

[0036] The PHY layer can be configured by one or more frequencies / carriers, and the technology of setting and using multiple frequencies simultaneously in one base station is called carrier aggregation (CA). Unlike using only one carrier for communication between the UE and the base station (E-UTRAN NodeB, eNB), the CA technology additionally uses a primary carrier and one or more secondary carriers so that the transmission capacity can be significantly increased by the number of secondary carriers. In LTE and NR systems, a cell within a base station using a primary carrier is called a primary cell (PCell), and a cell within a base station using a secondary carrier is called a secondary cell (SCell). The technology for extending CA functionality to two base stations is called dual connectivity (DC).

[0037] In the DC technology, the UE can be connected to the main base station (i.e., the main E-UTRAN NodeB (MeNB)) and the secondary base station (i.e., the secondary E-UTRAN NodeB (SeNB)) at the same time, and the cell belonging to the main base station is called the main cell group (MCG), and the cell served by the secondary base station is called the secondary cell group (SCG). Each cell group has a representative cell, and the representative cell of the MCG is called the PCell, and the representative cell of the SCG is called the primary secondary cell (PSCell). When using the above-mentioned NR, the MCG uses LTE technology (i.e., the LTE base station is used for the base station corresponding to the MCG), and the SCG uses NR (i.e., the NR base station is used for the base station corresponding to the SCG), so the UE can use LTE and NR at the same time. Alternatively, the NR base station can be used for the base station corresponding to the MCG, and the LTE base station can be used for the base station corresponding to the SCG, and the NR and NR base stations can be used for both the MCG and the SCG. As described above, the case for connecting different RATs to DC is collectively referred to as multi-RAT DC (MR-DC), and the DC between NR and NR is called NR-DC.

[0038] In LTE and NR systems, the UE can report PHR information to the base station according to predetermined conditions. The power headroom information represents the difference between the maximum transmit power and the transmit power, the maximum transmit power is configured for the UE, and the transmit power is estimated by the UE. The transmit power estimated by the UE is calculated based on the value used when the UE actually performs uplink transmission (the resulting value is called a real value), but when the UE does not actually perform uplink transmission, the transmit power estimated by the UE is calculated based on a predetermined equation defined in the standard rule (the resulting value is called a virtual value). By reporting the power headroom information, the base station can determine the available maximum transmit power of the UE. At the same time, when CA is used, the power headroom information can be transmitted to each secondary carrier.

[0039] Figure 3 is a diagram illustrating a carrier aggregation technology in a terminal according to an embodiment.

[0040] refer to Figure 3 , in one base station, multiple carriers are usually transmitted and received through several frequency bands. For example, when a carrier with a center frequency f1315 and a carrier with a center frequency f3310 are transmitted from the base station 305, conventionally, one terminal transmits or receives data by using one of the two carriers. However, a terminal with carrier aggregation capability can transmit or receive data simultaneously by using multiple carriers. The base station 305 can allocate more carriers to the terminal 330 with carrier aggregation capability according to conditions, thereby increasing the transmission rate of the UE 330.

[0041] When assuming that one cell is generally configured by one forward carrier and one reverse carrier, CA can be understood in a manner that a UE transmits or receives data simultaneously through multiple cells, where the forward carrier and the reverse carrier are transmitted to or received from one base station. Therefore, the maximum transmission rate increases in proportion to the number of aggregated carriers.

[0042] Here, the expression of a UE receiving data through a certain forward carrier or transmitting data through a certain reverse carrier has the same meaning as data transmitted or received using a control channel and a data channel provided by a cell corresponding to a center frequency and a frequency bandwidth of a designated corresponding carrier. In addition, for ease of description, the present disclosure is described with reference to an LTE system or an NR system, but the present disclosure can be applied to various wireless communication systems supporting CA.

[0043] Even when CA is performed or not performed, the reverse transmission (i.e., the transmission from the UE to the base station) may cause interference in the reverse transmission of another cell, and therefore, the reverse transmission output needs to be maintained at an appropriate level. To this end, when the UE performs reverse transmission, the UE calculates the reverse transmission output by using a predetermined function, and performs reverse transmission based on the calculated reverse transmission output. For example, the UE can calculate the value of the requested reverse transmission output by inputting scheduling information such as the amount of allocated transmission resources, the modulation and coding scheme (MCS) level to be applied, and input values ​​such as a path loss value for estimating the channel state into a specific function, and can perform reverse transmission by applying the calculated value of the requested reverse transmission output.

[0044] The maximum transmission value of the UE limits the value of the reverse transmission output applicable to the UE. When the calculated request value of the reverse transmission output is greater than the maximum transmission value of the UE, the UE applies the maximum transmission value for reverse transmission. Due to insufficient reverse transmission output, the quality of reverse transmission may deteriorate. The base station can perform scheduling to prevent the requested transmission output from exceeding the maximum transmission value. However, some parameters including path loss cannot be detected by the base station. Therefore, when necessary, the UE transmits a PHR to report the status of the UE's remaining transmission power or available transmission output to the base station.

[0045] Factors that affect the available transmission output are 1) the amount of allocated transmission resources, 2) the MCS to be applied to reverse transmission, 3) the path loss of the relevant forward carrier, 4) the accumulated value of the output control command, etc. Among these factors, the path loss (PL) or the accumulated value of the output control command may be different depending on the reverse carrier, so when multiple reverse carriers are aggregated in one UE, it is reasonable to configure whether to transmit PHR for each reverse carrier. However, in order to efficiently transmit PHR, one reverse carrier can report the PH of multiple reverse carriers. According to the operating strategy, the PH can be requested by a carrier that does not actually transmit PUSCH. Therefore, for this case, it is more efficient for one reverse carrier to report all PHs of multiple reverse carriers. To do this, the existing PHR must be extended. Multiple PHs to be included in one PHR can be configured according to a predetermined order.

[0046] The PHR is triggered when the PL change of the forward carrier of the general connection exceeds a predetermined reference value, when the prohibitPHR-Timer expires, or when a predetermined time has passed after the generation of the PHR. Even when the PHR is triggered, the UE does not transmit the PHR immediately, but waits until the reverse transmission is possible, for example, the time point when the reverse transmission resources are allocated. This is because the PHR is not information that should be processed quickly.

[0047] Figure 4 is a diagram illustrating dual connectivity according to an embodiment.

[0048] By using DC technology, the UE can connect to two base stations at the same time, and Figure 4 It is shown that when UE 405 is simultaneously connected to a macro base station 400 using LTE technology and a small cell base station 410 using NR technology, data transmission or reception is performed. This is called E-UTRAN-NR dual connectivity (EN-DC).

[0049] In the above case, the macro base station 400 is called MeNB, and the small cell base station 410 is called a secondary 5G Node B (SgNB). There may be multiple small cells in the service coverage of the MeNB, and the MeNB is connected to the SgNB via a wired backhaul network 415. A group of service cells provided from the MeNB is called MCG 420, and one service cell in the MCG is of course a PCell 425 having all functions performed by an existing cell (such as connection establishment, connection reconstruction, switching, etc.). In the PCell, the uplink control channel has a PUCCH. Service cells other than the PCell are called SCells 430.

[0050] Figure 4The diagram shows a situation where the MeNB provides one SCell and the SgNB provides three SCells. A group of service cells provided by the SgNB is called SCG 440.

[0051] When the UE transmits data to or receives data from two base stations, the MeNB may transmit a command to the SgNB for adding, changing, and removing a serving cell provided by the SgNB. In order to transmit the command, the MeNB may configure the UE to measure the serving cell and the neighboring cell. Based on the configuration information, the UE may report the measurement results to the MeNB. In order for the SgNB to effectively transmit data to or receive data from the UE, the SgNB requires the serving cell to be similarly used as the PCell of the MCG, and in the present disclosure, the serving cell is referred to as the PSCell 435. The PSCell is configured as one of the serving cells of the SCG and is characterized by having a PUCCH as an uplink control channel. The UE uses the PUCCH to transmit HARQ ACK / NACK information, channel state information (CSI) information, scheduling requests (SRs), etc. to the base station.

[0052] In the DC scenario, MCG and SCG each have an independent MAC entity. That is, there are two MAC entities in DC. Therefore, various functions of MAC (e.g., PHR reporting, etc.) can be performed independently of each other for each base station.

[0053] Figure 5A is a diagram showing an uplink transmission method according to an embodiment.

[0054] exist Figure 5A In the example 1, example 1 corresponds to a situation where two serving cells (i.e., PCell 501 and SCell 503) are configured in the UE, and then the UE performs uplink transmission according to the scheduling of the base station. In this case, due to the limitations of the transmission method and the RF structure, the UE cannot transmit PUCCH and PUSCH simultaneously in one serving cell. Therefore, the UE transmits a PUSCH (indicated by reference numeral 505) with PUCCH information embedded therein. The UE transmits the PUCCH information through the PCell, or when there is no PUSCH transmitted through the PCell, the UE transmits the PUCCH information through the SCell with a low index in the SCell. The PHR message is transmitted through a part of the PUSCH, and therefore, in this case, the UE is required to report only the maximum transmit power P transmitted from each serving cell. CMAX,c The power headroom value is obtained by subtracting the transmit power consumed by transmitting the PUSCH (indicated by reference numerals 505 and 507). This is called a Type 1 power headroom.

[0055] Example 2 shows a situation in which two serving cells, namely PCell 511 and SCell 513, are configured for the UE, and then the UE performs uplink transmission according to the scheduling of the base station. In this case, the UE is able to transmit PUCCH and PUSCH simultaneously in one serving cell, or transmit PUCCH and PUSCH separately by using an uplink transmission technology in which simultaneous transmission is possible. Here, in the PCell (or when PUCCH transmission through the SCell is possible, it is applied to the SCell), the UE is required to report the maximum transmission power P from the PCell by considering not only the transmission power consumed by PUSCH transmission 517 and 519, but also the transmission power consumed by PUCCH transmission 515. CMAX,c The power headroom value obtained by subtracting the transmit power values ​​used for PUSCH transmission and PUCCH transmission from the power headroom value. This is called Type 2 power headroom.

[0056] When the UE reports the type 1 power headroom or the type 2 power headroom, the UE reports the power headroom by using a MAC control element (CE) which is a control message of the MAC layer, and more specifically, the UE may report the power headroom by using a single-entry PHR MAC CE format 521 or a multi-entry PHR MAC CE format 531. If only a single carrier is used, the UE may use the single-entry PHR MAC CE format 521, and if dual connectivity is configured (or CA is configured), the UE may use the multi-entry PHR MAC CE format 531.

[0057] When using the single-entry PHR MAC CE format, the UE transmits the power headroom 523 and P for the serving cell. CMAX，f， c 525,P CMAX，f，c 525 is the maximum transmit power of the serving cell.

[0058] The value of the power headroom is used to indicate one of a range between -32 dB and 38 dB as shown in Table 1 below, and this indicates available transmit power of the UE.

[0059] [Table 1]

[0060] Report value Measurement value (dB) POWER_HEADROOM-0 PH<-32 POWER_HEADROOM_1 -32≤PH<-31 POWER_HEADROOM_2 -31≤PH<-30 POWER_HEADROOM_3 -30≤PH<-29 … … POWER_HEADROOM_53 20≤PH<21 POWER_HEADROOM_54 21≤PH<22 POWER_HEADROOM_55 22≤PH<24 POWER_HEADROOM_56 24≤PH<26 POWER_HEADROOM_57 26≤PH<28 POWER_HEADROOM_58 28≤PH<30 POWER_HEADROOM_59 30≤PH<32 POWER_HEADROOM_60 32≤PH<34 POWER_HEADROOM_61 34≤PH<36 POWER_HEADROOM_62 36≤PH<38 POWER_HEADROOM_63 PH≥38

[0061] The UE can calculate the available transmit power by using equation (1) as described below or an equation corresponding thereto.

[0062]

[0063] In equation (1), when PUSCH transmission is performed at time point i in serving cell c (frequency f), based on the maximum reverse transmission power PCMAX,f,c (i) The number of resource blocks M PUSCH RB,b,f,c (i) Power offset Δ derived from MCS TF，c (i), path loss PL c and the accumulated TPC command f c (i) to calculate PH(i). In equation (1), PL c Represents the path loss of the cell configured to provide path loss for the serving cell c. The path loss used to determine the reverse transmission power of the random serving cell is the path loss of the forward channel of the corresponding cell or the path loss of the forward channel of another cell. The base station selects the path loss to be used from the above path losses through a message of the RRC layer and notifies the UE of the selected path loss.

[0064] If the UE uses multiple beams in a cell, the base station informs the UE of the beam or reference signal to be selected for measurement and calculation. c (i) is the accumulated value of the transmit power control command of serving cell c. O_PUSCH,C Denotes a parameter of a higher layer and is configured as the sum of a cell-specific value and a UE-specific value.

[0065] Typically, different PUSCH transmission types are applied. O_PUSCH,C values, such as semi-persistent scheduling, dynamic scheduling, and random access response. c is a 3-bit cell-specific value provided via a higher layer, indicating the weighting value applied to the path loss during the calculation of the downlink transmission output (i.e., the larger the weighting value, the greater the impact of the path loss on the downlink transmission output). The applicable weighting values ​​are restricted according to the type of PUSCH transmission. The value of j is used to indicate the type of PUSCH. The value of j is configured such that j=0 indicates semi-persistent scheduling, j=1 indicates dynamic scheduling, and j=2 indicates random access response. In equation (1), if there is no PUSCH transmission in a particular serving cell, then according to the definition M PUSCH and Δ TF The above equation (1) will not apply.

[0066] On the other hand, in P CMAX_L,f,c and P CMAX_H,f,c Determine P CMAX,f,c , the P CMAX,f,c is the UE maximum transmit power of serving cell c (of frequency f), as shown in equation (2) described below, or determined using an equation corresponding thereto.

[0067] P CMAX_L,f,c ≤P CMAX,f,c ≤P CMAX_H,f,c

[0068] P CMAX_L,f,c =MIN{P EMAX,c -ΔT C，c ,(P PowerClass -ΔP PowerClass )-MAX(MAX(MPR c , A-MPR c )+ΔT IB,c +ΔT C，c +ΔT RxSRS , P-MPR c )}

[0069] P CMAX_H,f,c =MIN{P EMAX,c , PPowerClass-ΔP PowerClass} (2)

[0070] In equation (2), P CMAX_H,f,c (It is P CMAX,f,c The maximum value of P is determined as the P transmitted directly by the base station. EMAX,c The value of P and the P determined for each frequency band PowerClass -ΔP PowerClass In addition, in equation (2), P CMAX_L,f,c (It is P CMAX,f,c The minimum value of P is determined as a value reduced by an additional factor from each maximum value. EMAX,c The value is reduced by ΔT according to the band-specific conditions C，c =1.5dB. In addition, the P determined for each frequency band is determined with reference to the larger value of the following values: PowerClass -ΔP PowerClass The value of can be reduced by the minimum value of the maximum transmit power of the UE: by considering the maximum power reduction (MPR) determined according to the transmit modulation and transmit bandwidth of the UE C ), and the additional maximum power reduction (A-MPR) determined by the additional signaling sent by the base station to the UE to reduce interference in adjacent frequency bands. C ) value (also called the network signaling (NS) value), and the power management maximum power reduction (P-MPR) used to reduce the transmission power to meet the value required for the electromagnetic wave energy to be absorbed into the human body C )value.

[0071] For example, in a system operating at a high frequency such as an NR system, the UE may perform transmission at high power. However, if transmission is performed at high power, it may be harmful to the human body, and thus the maximum transmission value may be adjusted according to a desired value for adjusting high power transmission. As described above, when the maximum transmission value is adjusted according to the P-MPR CWhen the actual transmit power is adjusted by reducing the minimum value of the maximum transmit power, it is called power backoff due to power control (power management).

[0072] Figure 5B is a diagram showing a multi-entry PHR MAC CE format according to an embodiment.

[0073] Reference Figure 5B , when using the multi-entry PHR MAC CE format, the UE indicates the serving cell to which the power headroom report is transmitted through the bitmap 533, and for the serving cell to which the report is made through the bitmap and the serving cell to which the unconditional report is made, the power headroom may be configured as reference numerals 541, 551, and 561. In addition, if reporting is required, the UE reports the P corresponding to the power headroom together. CMAX,f,c Values ​​(denoted by reference numerals 543, 553, and 563). The UE reports the power headroom by using a field having a length of 6 bits as shown, and in LTE, the power headroom has values ​​as shown in Table 2 below.

[0074] [Table 2]

[0075] Report value Measurement value (dB) POWER_HEADROOM_O -23≤PH<-22 POWER_HEADROOM_1 -22≤pH<-21 POWER_HEADROOM_2 -21≤PH<-20 POWER_HEADROOM_3 -20≤PH<-19 POWER_HEADROOM_4 -19≤PH<-18 POWER_HEADR00M_5 -18≤PH<-17 … … POWER_HEADR00M_57 34≤PH<35 POWER_HEADROOM_58 35≤PH<36 POWER_HEADROOM_59 36≤PH<37 POWER_HEADROOM_60 37≤≤PH<38 POWER_HEADROOM_61 38≤PH<39 POWER_HEADROOM_62 39≤PH<40 POWER_HEADROOM_63 PH≥40

[0076] NR can be divided into two frequency ranges according to the frequency range in which the base station operates, as shown in Table 3 below.

[0077] [Table 3]

[0078] Frequency range name Corresponding frequency range FR1 450MHz-6000MHz FR2 24250MHz-52600MHz

[0079] The transmit power of a UE required by a base station operating in FR1 and a base station operating in FR2 may be significantly different. Therefore, a separate table different from Table 2 in LTE may be defined according to each frequency range (ie, each of FR1 and FR2).

[0080] For example, Table 4 can be used for PHR reporting of a base station operating in FR1 in an NR base station. For convenience, Table 4 shows the same table as Table 2 in LTE because there is no significant difference in the frequency range of LTE operation, but it can have different values.

[0081] [Table 4]

[0082] Report value Measurement value (dB) POWER_HEADROOM_0 -23≤PH<-22 POWER_HEADROOM_1 -22≤PH<-21 POWER_HEADROOM_2 -21≤PH<-20 POWER_HEADROOM_3 -20≤PH<-19 POWER_HEADROOM_4 -19≤PH<-18 POWER_HEADROOM_5 -18≤PH<-17 … … POWER_HEADROOM_57 34≤PH<35 POWER_HEADROOM_58 35≤PH<36 POWER_HEADROOM_59 36≤PH<37 POWER_HEADROOM_60 37≤PH<38 POWER_HEADROOM_61 38≤PH<39 POWER_HEADROOM_62 39≤PH<40 POWER_HEADROOM_63 PH≥40

[0083] In addition, for example, Table 5 can be used for PHR reporting of base stations operating in FR1 in NR base stations.

[0084] [Table 5]

[0085] Report value Measurement value (dB) POWER_HEADROOM_O -13≤PH<-12 POWER_HEADROOM_1 -12≤PH<-11 POWER_HEADROOM_2 -11≤PH<-10 POWER_HEADROOM_3 -10≤PH<-9 POWER_HEADROOM_4 -9≤PH<-8 POWER_HEADROOM_5 -8≤PH<-7 … … POWER_HEADROOM_57 44≤PH<45 POWER_HEADROOM_58 45≤PH<46 POWER_HEADROOM_59 46≤PH<47 POWER_HEADROOM_60 47≤PH<48 POWER_HEADROOM_61 48≤PH<49 POWER_HEADROOM_62 49≤PH<50 POWER_HEADROOM_63 PH≥50

[0086] In the case of a multi-entry PHR MAC CE, a P bit 535 and a V bit 537 may also be included.

[0087] The P bit may indicate information indicating power backoff that occurs due to power management. That is, when the maximum transmit power value of the corresponding serving cell becomes lower than the original value due to power backoff, the UE may configure the P bit to 1 and report it to the base station. In addition, the UE may notify the base station of the P value reported by the UE to the corresponding serving cell. CMAX，f，c The values ​​are those obtained by adjustment due to the above reasons.

[0088] The V bit may represent information indicating whether uplink transmission to each serving cell is actually performed according to scheduling information at the time point when the UE reports the multi-entry PHR MAC CE. At the time point when the multi-entry PHR MAC CE is reported, there will be a situation where uplink data is actually transmitted or not transmitted to each serving cell according to the scheduling information. When uplink data is actually transmitted, the V bit is configured to "0", and the PH value may be calculated and reported according to the actual transmission. However, when uplink data is not transmitted, the V bit is configured to "1", and the value calculated under the assumption that a predetermined virtual transmission has been performed is reported as "PH". Virtual transmission is called a PUSCH reference format.

[0089] The values ​​of the P bit and the V bit can be configured in various ways. In other words, configuring the P bit to "0" can indicate that the maximum transmit power value is lower than the original value, while configuring the V bit to "1" can indicate that the PH value is a value calculated based on actual transmission.

[0090] Therefore, when the current base station reports PHR to each cell that is activated and configured for the UE, even if the same PH reporting field as the multi-entry PHR format is used according to the RAT and the operating frequency of the corresponding service cell, the UE can generate a value by using a table according to the corresponding service cell type and report the value to the base station.

[0091] Even when using the single-entry PHR MAC CE described above, there may be a need to reduce P due to power backoff that occurs due to power management. CMAX,f,c For this reason, even in the case of a single-entry PHR MAC CE, it may be considered to notify the P including the P bit 557. CMAX,f,c The value method.

[0092] In addition, when P CMAX,f,c When the value of needs to be reduced due to power backoff caused by power management, you can use Figure 5C The format shown is used to transmit the power headroom for detailed reporting without using Figure 5BThe format described in .

[0093] Figure 5C is a diagram showing a multi-entry PHR MAC CE format according to an embodiment.

[0094] When the base station explicitly configures the UE to use the new format, the UE can transmit the report by using the format as indicated in the current example. For example, when the base station configures the UE with reportPMPRenabled by newly introducing a field such as reportPMPRenabled, both the single-entry PHR MAC CE and the multi-entry PHR MAC CE can use the format of reporting P bit and P-MPRC.

[0095] That is, in Figure 5C The single-entry PHR MAC CE format 5c-51 and the multiple-entry PHR MAC CE format 5c-31 described in Figure 5B Compared with P-MPR C Fields 5c-07, 5c-71, and 5c-75 and dynamic duty cycle fields 5c-09 and 5c-77 are added. Figure 5C The remaining reference numerals in Figure 5B The corresponding parts in are the same.

[0096] In more detail, if the UE configures the P bit to '1' for the corresponding cell (c), the P-MPRC fields 5c-07, 5c-71, and 5c-75 may be used to explicitly indicate a P-MPRC value for reducing transmit power.

[0097] In order to reuse the existing format as much as possible, two reserved bits of the existing format are reused, and therefore, the maximum number of P-MPRC values ​​that can be reported is 4. These four values ​​can be specific values ​​or ranges of values. For example, these four values ​​can indicate that in the case of bit 00, a value between 1dB and 5dB is used, in the case of bit 01, a value between 6dB and 10dB is used, in the case of bit 10, a value between 11dB and 15dB is used, and in the case of bit 11, a value of 16dB or higher is used. However, the above details are only one embodiment, and the scope of the present disclosure is not limited thereto. That is, the P-MPRC value or range indicated by the bit can be configured differently.

[0098] If the P bit is configured as "0", a reserved bit is used instead of the P-MPRC field in the legacy system, or even if the base station receives the content of the corresponding P-MPRC field, the base station may ignore the P-MPRC field. In particular, in the case of using a multi-entry PHR MAC CE, the P bit may be configured as "0" or "1" for each serving cell, and in the case where the serving cell is configured as "0", a reserved bit (indicated by reference numeral 5c-73) is used as in the legacy system, or even if the base station receives the content of the corresponding P-MPRC field, the base station may ignore the P-MPRC field.

[0099] In addition, the dynamic duty cycle fields 5c-09 and 5c-77 are fields that can be included even if one P field is configured as "1" in the corresponding format, and indicate the time length as to whether the UE can maintain power backoff.

[0100] The base station is configured via a separate indicator to use Figure 5C In the case of the new format shown in FIG. 1 , when even one P field is configured to be "1", the presence or absence of the dynamic duty cycle field is determined by including the dynamic duty cycle field. Alternatively, even in the case where the base station is configured to use the new format through a separate indicator, such as Figure 5C As shown, a method of indicating whether the dynamic duty cycle field is included by adding a separate indicator may be considered.

[0101] It is also possible to define a P-MPRC field by simply adding the P-MPRC fields 5c-07, 5c-71, and 5c-75 to the Figure 5C The format obtained by the new format shown in FIG. 5A does not add the dynamic duty cycle fields 5c-09 and 5c-77. In this way, the base station can obtain information indicating only the power reduced and transmitted by the UE.

[0102] The base station can accurately identify the amount of transmit power reduced by the UE and the length of time the transmit power is reduced, and can therefore release the corresponding serving cell (especially in the case of SCell), release the corresponding time, or perform switching to another cell.

[0103] When the PHR is transmitted to the base station, conditions (i.e., whether to trigger a report) can be defined, and in LTE and NR systems, the following conditions can be defined.

[0104] Condition 1: When the change in downlink reception strength of the serving cell belonging to the random MAC entity configured for the UE is equal to or greater than the value of phr-Tx-PowerFactorChange dB in the state where prohibitPHR-Timer expires.

[0105] That is, according to the above conditions, even if a signal strength change occurs in one of the service cells of the SCG in the DC scenario, the PHR can be reported to the MCG.

[0106] Condition 2: When the phr-PeriodicTimer (of the corresponding MAC entity) expires.

[0107] Condition 3: When initially configuring PHR reporting.

[0108] Condition 4: When an SCell including an uplink corresponding to a random MAC entity is activated.

[0109] Condition 5: When adding or changing the PSCell of the SCG and using dual connectivity technology.

[0110] Condition 6: When there are resources for uplink transmission via the serving cell corresponding to the random MAC entity configured for the UE in the state where the prohibitPHR-Timer has expired, if the amount of transmit power that should be reduced according to the power backoff due to power control needs to be equal to or greater than the value of the previously reported PHR MAC CE.

[0111] On the other hand, in the case of condition 6, when there is no P bit like the single-entry PHR MAC CE indicated by reference numeral 521, it may be difficult for the base station to know whether power backoff in the UE has occurred due to power control even when receiving the PHR MAC CE. To this end, condition 6 can be modified to condition 6-1 as follows.

[0112] Condition 6-1: When there are resources to be transmitted via the uplink of the serving cell corresponding to the random MAC entity configured for the UE in a state in which the prohibitPHR-Timer has expired, if the base station is configured to transmit a single-entry PHR MAC CE by including a P bit therein as format 551 while using multiple PHR MAC CEs or not using multiple PHR MAC CEs (i.e., using a single-entry MAC CE); and

[0113] When the amount by which the transmit power should be reduced according to power backoff due to power control needs to be equal to or greater than the value of phr-Tx-PowerFactorChange compared to the previously reported value of PHR MAC CE.

[0114] In addition, the prohibitPHR-Timer value and the phr-Tx-PowerFactorChange value used in condition 1 are used in condition 6 (or condition 6-1). However, in order to control the occurrence of power backoff respectively, the base station can configure the values ​​of condition 6 and condition 6-1 respectively. For example, the base station configures the phr-prohibitTimerPbit value and the phr-Tx-PowerFactorChangePbit value for condition 6 and condition 6-1 respectively, so the additional configured values ​​can be used instead of configuring the prohibitPHR-Timer and phr-Tx-PowerFactorChange values ​​for condition 6 and condition 6-1. The additional configured values ​​can be transmitted to the UE via, for example, an RRC message. This can be applied to (updated) single-entry PHR MAC CE and multi-entry PHR MAC CE.

[0115] According to the above conditions, if a PHR triggering condition occurs in each base station, the UE can generate a PHR and report the PHR to the corresponding base station. However, if the above-mentioned dynamic power sharing is not supported, if the PHR is triggered due to an event that has occurred in another MAC entity other than its own MAC entity, even if the UE reports the PHR, it is impossible to report the power headroom value of the serving cell corresponding to the corresponding MAC entity, and therefore, it may be unnecessary to transmit only the PHR value belonging to its own MAC entity.

[0116] Figure 6 is a diagram illustrating an operation sequence of a UE according to a method of reporting a PHR when power backoff occurs due to power control according to an embodiment.

[0117] The method starts from 601. In 603, the UE in the dormant state (IDLE) searches and selects an appropriate NR base station (or cell) and performs access to the corresponding base station. To this end, the UE can transmit an RRCRequest message of the RRC layer to the base station, receive an RRCSetupComplete message from the base station accordingly, and transmit the RRCSetupComplete message back to the base station to complete the access process.

[0118] If the UE has not previously accessed the operator network, or if there is no UE capability information in the core network due to mobility, the base station can instruct the UE to report the UE capability information by using a UECapabilityEnquery message of the RRC layer.

[0119] Therefore, the UE can report its own capability information to the base station by using the UECapabilityInformation message of the RRC layer. At 605, the UE includes a bit (e.g., singleEntryPbit) indicating whether the format including the P bit in the single-entry PHR MAC CE is supported in the UE capability information, and transmits the bit to the base station. In addition, when the base station has the UE capability information, the operation of transmitting the UE capability information message can be omitted.

[0120] Thereafter, at 607, the UE receives an RRCReconfiguration message of the RRC layer from the base station, and the RRCReconfiguration message may include configuration information.

[0121] The configuration information may include configuration related to PHR reporting. The configuration related to PHR reporting may be included in a phr-Config information element (IE) in an RRCReconfiguration message and transmitted to the UE.

[0122] The phr-Config IE may include whether to use multiplePHR, and at least one of the values ​​such as phr-ProhibitTimer, phr-PeriodicTimer, and phr-Tx-PowerFactorChange. In addition, according to the UE capability, when the base station configures multiplePHR as "pseudo" (i.e., when the use of the single-entry PHR MAC CE is configured), the base station may also configure the UE to use a format that includes the above-mentioned P bit in the single-entry PHR MAC CE. For example, a bit such as singleEntryPbitEnabled (e.g., an indicator indicating whether the P bit for singlePHR is used) may be used to indicate whether the P bit is included in the single-entry PHR MAC CE.

[0123] The configuration information included in the above RRC message is merely an example of the present disclosure, and the scope of the present disclosure is not limited thereto. For example, some information may not be included, and only some information may be included.

[0124] In addition, if the base station wishes to separately control the triggered PHR when power backoff occurs due to the above-mentioned power control (power management), the base station can additionally configure phr-ProhibitTimerPbit and phr-Tx-PowerFactorChangePbit, which are new parameters corresponding to the previously used phr-ProhibitTimer and phr-Tx-PowerFactorChangeChangePbit.

[0125] If phr-prohibitTimerPbit and phr-Tx-PowerFactorChangePbit are not signaled, the UE may determine whether to trigger PHR by using phr-prohibitTimer and phr-Tx-PowerFactorChange in the PHR triggering condition of condition 6 above.

[0126] However, if phr-prohibitTimerPbit and phr-Tx-PowerFactorChangePbit are signaled, the UE may determine whether to trigger PHR based on condition 6 among the conditions for triggering PHR by using phr-prohibitTimerPbit and phr-Tx-PowerFactorChangePbit.

[0127] In addition, the field names such as phr-prohibitTimer and phr-prohibitTimerPbit described above are used for convenience of explanation and can be replaced by terms such as first prohibition timer and second prohibition timer. In addition, phr-Tx-PowerFactorChange and phr-Tx-PowerFactorChange can be replaced by first received signal strength change information, second received signal strength change information, etc.

[0128] Alternatively, the UE may determine whether to trigger the PHR using condition 6-1 instead of the above condition 6. That is, in a state where the prohibitPHR-Timer expires, when there are resources to be transmitted via the uplink of the serving cell corresponding to the random MAC entity configured for the UE, when multiple PHR MAC CEs are used, or when multiple PHR MAC CEs are not used (i.e., single-entry MAC CEs are used), when the base station is configured to transmit a single-entry PHR MAC CE by including the P bit therein as format 551, when the amount of transmit power that should be reduced due to power backoff caused by power control needs to be equal to or greater than the amount of phr-Tx-PowerFactorChange compared to the value of the previously reported PHR MAC CE, the UE may trigger the PHR. In addition, when phr-prohibitTimerPbit and phr-Tx-PowerFactorChangePbit are configured, the UE may replace phr-prohibitTimer and phr-Tx-PowerFactorChangeChange with phr-prohibitTimerPbit and phr-Tx-PowerFactorChangePbit in condition 6-1. In the case where the base station configures a separate parameter for power backoff as described above, if a power backoff situation occurs due to corresponding power control, the UE may determine the triggering of PHR by using the separate parameter, and may report the configuration to the base station more quickly or more freely according to the configured value.

[0129] The UE that has received the configuration information transmits a confirmation message for reception. The RRCReconfigurationComplete message may be used as a confirmation message.

[0130] Thereafter, the UE determines whether a subsequent PHR report triggering condition has occurred according to the parameters configured by the base station as described above.

[0131] Condition 1: When the change in downlink reception strength of the serving cell belonging to the random MAC entity configured for the UE is equal to or greater than the value of phr-Tx-PowerFactorChange dB in the state where prohibitPHR-Timer expires.

[0132] Condition 2: When phr-PeriodicTimer (of MAC entity) expires.

[0133] Condition 3: When initially configuring PHR reporting.

[0134] Condition 4: When an SCell including an uplink corresponding to a random MAC entity is activated.

[0135] Condition 5: When the primary cell (PSCell) of the SCG is added or changed and dual connectivity technology is used at the same time.

[0136] Condition 6: When transmission is performed via the uplink of the serving cell corresponding to the random MAC entity configured for the UE in a state where prohibitPHR-Timer has expired, if the amount by which the transmit power should be reduced (according to transmit power adjustment, etc.) needs to be equal to or greater than the value of phr-Tx-PowerFactorChange; or

[0137] Condition 6-1: When there are resources for uplink transmission via the serving cell corresponding to the random MAC entity configured for the UE in a state in which the prohibitPHR-Timer has expired, if the base station is configured to transmit a single-entry PHR MAC CE by including the P bit, as format 551, while using multiple PHR MAC CEs or not using multiple PHR MAC CEs (i.e., using a single-entry MAC CE), or if the amount of transmit power that should be reduced according to power backoff due to power control needs to be equal to or greater than the value of the phr-Tx-PowerFactorChange compared to the value of the previously reported PHR MAC CE.

[0138] In Condition 6 and Condition 6-1, when phr-prohibitTimerPbit and phr-Tx-PowerFactorChangePbit are additionally configured, the UE replaces phr-prohibitTimer and phr-Tx-PowerFactorChangePbit with phr-prohibitTimerPbit and phr-Tx-PowerFactorChangePbit.

[0139] In case of using condition 6-1, if singleEntryPbitEnabled is not configured, PHR may not be triggered.

[0140] exist Figure 6 In the embodiment of , it is assumed that power backoff in the UE occurs due to power control and thus triggers a PHR report. Therefore, the UE assumes that condition 6 or condition 6-1 is satisfied.

[0141] Therefore, at 611, the UE determines the MAC CE format to be reported to the PHR according to whether the multiplePHR configuration information and singleEntryPbitEnable are configured from the base station.

[0142] In the case where multiplePHR is configured as "true" (i.e., when the base station configures CA or DC in the UE), a multiple-entry PHR MAC CE is used, and the PHR MAC CE can be configured by configuring the P bit included in the MAC CE to "1" (or "0", depending on the configuration) for the serving cell (carrier) in which power backoff has occurred. At 613, the P bit of the corresponding serving cell is set to "1". CMAX,f,c The value is configured to be adjusted due to power backoff.

[0143] In the case where multiplePHR is configured as "fake" (i.e., when the base station uses only a single serving cell because the base station does not configure CA or DC in the UE), if singleEntryPbitEnabled is not configured, the UE generates a PHR MAC CE by using a conventional single-entry PHR MAC CE 521 that does not include a P bit. Figure 6 In the embodiment, assuming that PHR is triggered, and when condition 6-1 is used as described above, if singleEntryPbitEnabled is not configured, PHR itself may not be triggered.

[0144] In the case where multiplePHR is configured as "pseudo" (i.e., when the base station does not configure CA or DC in the UE and only a single serving cell is used), if singleEntryPbitEnabled is configured, the UE may generate a PHR MAC CE by using a single-entry PHR MAC CE including a P bit, as shown in reference numeral 551. That is, at 615, by configuring the P bit in the current MAC CE to "1" and setting the P bit of the corresponding serving cell to "1", the UE generates a PHR MAC CE by using a single-entry PHR MAC CE including a P bit. CMAX,f,c The PHR MAC CE is configured with a value adjusted due to power backoff.

[0145] Thereafter, the UE reports the generated PHR to the base station and notifies the base station of the redundant power of the UE at 619. The method ends at 621. Therefore, the base station can determine the current redundant power of the UE and schedule the UE accordingly.

[0146] Figure 7 is a diagram showing a block configuration of a UE in a wireless communication system according to an embodiment.

[0147] Reference Figure 7 , the UE includes a radio frequency (RF) processor 710, a baseband processor 720, a memory 730, and a controller 740.

[0148] The RF processor 710 performs functions including signal frequency band conversion and amplification in order to transmit or receive signals through a wireless channel. That is, the RF processor 710 up-converts the baseband signal provided by the baseband processor 720 into an RF band signal, then transmits the RF band signal via an antenna, and down-converts the RF band signal received via the antenna into a baseband signal. For example, the RF processor 710 may include a transmit filter, a receive filter, an amplifier, a mixer, an oscillator, a digital-to-analog converter (DAC), an analog-to-digital converter (ADC), etc. Although Figure 7 Only one antenna is shown, but the UE may include multiple antennas. In addition, the RF processor 710 may include multiple RF chains. In addition, the RF processor 710 may perform beamforming. For beamforming, the RF processor 710 may adjust the phase and amplitude of each signal transmitted or received via multiple antennas or antenna elements.

[0149] The baseband processor 720 performs a conversion function between a baseband signal and a bit string according to the physical layer specification of the system. For example, in data transmission, the baseband processor 720 generates complex symbols by encoding and modulating the transmitted bit string. In addition, in data reception, the baseband processor 720 reconstructs the received bit string by demodulating and decoding the baseband signal provided from the RF processor 710. For example, when transmitting data according to the OFDM scheme, the baseband processor 720 generates complex symbols by encoding and modulating the transmitted bit string, maps the complex symbols to subcarriers, and configures the OFDM symbol by performing an inverse fast Fourier transform (IFFT) operation and inserting a cyclic prefix (CP). In addition, in data reception, the baseband processor 720 can divide the baseband signal provided from the RF processor 710 into OFDM symbol units, and restore the signal mapped to the subcarrier by performing a fast Fourier transform (FFT) operation, and then reconstruct the received bit string by demodulating and decoding the signal.

[0150] As described above, the baseband processor 720 and the RF processor 710 transmit and receive signals. Therefore, the baseband processor 720 and the RF processor 710 may be referred to as a transmitter, a receiver, a transceiver, or a communicator. In addition, at least one of the baseband processor 720 and the RF processor 710 may include a plurality of communication modules supporting different wireless access technologies. In addition, at least one of the baseband processor 720 and the RF processor 710 may include different communication modules configured to process signals of different frequency bands. For example, different wireless access technologies may include wireless LANs (e.g., IEEE 802.11), cellular networks (e.g., LTE), and the like. Examples of different frequency bands may include ultra-high frequency (SHF) bands (e.g., 2.5 GHz or 5 GHz) and millimeter wave bands (e.g., 60 GHz).

[0151] The memory 730 may store data for the operation of the UE, such as default programs, applications, and configuration information. In particular, the memory 730 may store information related to wireless LAN nodes that perform wireless communications using wireless LAN access technologies. In addition, the memory 730 provides the stored data in response to a request from the controller 740.

[0152] The controller 740 controls the overall operation of the UE. For example, the controller 740 transmits or receives a signal through the baseband processor 720 and the RF processor 710. In addition, the controller 740 records data in the memory 730 or reads data from the memory 730. To this end, the controller 740 may include at least one processor. For example, the controller 740 may include a communication processor configured to perform communication control and an application processor (AP) configured to control a higher layer such as an application. According to one embodiment, the controller 740 includes a multi-connection processor 742, which is configured to perform processing to operate in a multi-connection mode. For example, the controller 740 may perform control so that the UE performs Figure 6 The process shown in the UE operation shown.

[0153] According to one embodiment, the controller 740 determines whether to configure the P bit according to the UE capabilities and the configuration information received from the base station even when using the single-entry PHR MAC CE, and if it is determined to report the PHR, the controller generates the P bit and instructs the base station to transmit the P bit.

[0154] Figure 8 is a diagram showing a structure of a base station according to an embodiment.

[0155] Reference Figure 8 , the base station includes a transceiver 810, a controller 820, and a memory 830. In the present disclosure, the controller may be defined as a circuit, an application specific integrated circuit, or at least one processor.

[0156] The transceiver 810 may transmit signals to or receive signals from other network entities. For example, the transceiver 810 may receive UE capabilities and transmit configuration information to the UE.

[0157] According to the embodiments provided in the present disclosure, the controller 820 may control the overall operation of the base station. For example, the controller 820 may control the signal flow between the various blocks so as to perform the operations according to the above flowchart. For example, the controller 820 may perform control to receive the PHR determined according to the above method from the UE, and adjust the transmit power accordingly, thereby transmitting data.

[0158] The memory 830 may store at least one of information transmitted or received by the transceiver 810 and information generated by the controller 820 .

[0159] The methods disclosed in the claims and / or the methods according to the various embodiments described in the specification of the present disclosure may be implemented by hardware, software, or a combination of hardware and software.

[0160] When the method is implemented by software, a computer-readable storage medium for storing one or more programs (software modules) may be provided. One or more programs stored in the computer-readable storage medium may be configured to be executed by one or more processors in an electronic device. At least one program may include instructions that cause the electronic device to perform the method according to various embodiments of the present disclosure as defined in the appended claims and / or disclosed herein.

[0161] Programs (software modules or software) can be stored in non-volatile memory, including random access memory and flash memory, read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), magnetic disk storage devices, compact disk ROM (CD-ROM), digital versatile disk (DVD), or other types of optical storage devices, or magnetic tape cassettes. Alternatively, any combination of some or all of them can form a memory storing a program. In addition, a plurality of such memories can be included in an electronic device.

[0162] In addition, the program can be stored in a connectable storage device that can access the electronic device through a communication network such as the Internet, an intranet, a local area network (LAN), a wide area network (WLAN), and a storage area network (SAN), or a combination thereof. Such a storage device can access the electronic device via an external port. In addition, a separate storage device on a communication network can access the portable electronic device.

[0163] In the above detailed embodiments of the present disclosure, the elements included in the present disclosure are represented in the singular or plural, depending on the detailed embodiments presented. However, for the convenience of description, the singular form or the plural form is appropriately selected according to the presented situation, and the present disclosure is not limited to the elements represented in the singular or plural. Therefore, the elements represented in the plural may also include a single element, or the elements represented in the singular may also include multiple elements.

[0164] Although the embodiments have been described in the detailed description of the present disclosure, various modifications and changes can be made thereto without departing from the spirit and scope of the present disclosure. Therefore, the scope of the present disclosure should not be limited to the embodiments, but should be defined by the appended claims and their equivalent expressions.

Claims

1. A method performed by a terminal in a communication system, the method comprising: Receiving configuration information including a first power headroom report (PHR) configuration and a second PHR configuration from a base station, wherein the first PHR configuration includes a first prohibit timer, and the second PHR configuration includes a threshold and a second prohibit timer; identifying whether a PHR is triggered based on the configuration information; as well as transmitting the PHR to the base station if a power management maximum power reduction (P-MPR) value applied to meet the required value is greater than or equal to the threshold and the second prohibit timer is not running; In which, when the P field included in the PHR is set to 1, the field included in the PHR indicates the P-MPR value, and the length of the field is 2 bits.

2. The method according to claim 1, wherein: The field indicates a range of P-MPR values; and In which, when the P field is set to 0, the reserved field is used.

3. The method according to claim 1, further comprising: In case the PHR is triggered, starting the second prohibit timer, The PHR includes a single-entry PHR or a multi-entry PHR.

4. A method performed by a base station in a communication system, the method comprising: Transmitting configuration information including a first power headroom report PHR configuration and a second PHR configuration to a terminal, wherein the first PHR configuration includes a first prohibition timer, and the second PHR configuration includes a threshold and a second prohibition timer; and In case that the PHR is triggered, receiving the PHR from the terminal, wherein the PHR is triggered when the power management maximum power reduction P-MPR value applied to meet the required value is greater than or equal to the threshold and the second prohibition timer is not running, In which, when the P field included in the PHR is set to 1, the field included in the PHR indicates the P-MPR value, and the length of the field is 2 bits.

5. The method according to claim 4, wherein: The field indicates a range of P-MPR values; and In which, when the P field is set to 0, the reserved field is used.

6. The method according to claim 4, wherein: In case the PHR is triggered, the second prohibit timer is started; and The PHR includes a single-entry PHR or a multi-entry PHR.

7. A terminal in a communication system, the terminal comprising: Transceiver; as well as a controller coupled to the transceiver and configured to: Receiving configuration information including a first power headroom report (PHR) configuration and a second PHR configuration from a base station, wherein the first PHR configuration includes a first prohibit timer, and the second PHR configuration includes a threshold and a second prohibit timer; identifying whether a PHR is triggered based on the configuration information; as well as transmitting the PHR to the base station if a power management maximum power reduction (P-MPR) value applied to meet the required value is greater than or equal to the threshold and the second prohibit timer is not running; In which, when the P field included in the PHR is set to 1, the field included in the PHR indicates the P-MPR value, and the length of the field is 2 bits.

8. The terminal according to claim 7, wherein: The field indicates a range of P-MPR values; and In which, when the P field is set to 0, the reserved field is used.

9. The terminal according to claim 7, wherein: The controller is further configured to start the second prohibit timer if the PHR is triggered, The PHR includes a single-entry PHR or a multi-entry PHR.

10. A base station in a communication system, the base station comprising: Transceiver; as well as a controller coupled to the transceiver and configured to: Transmitting configuration information including a first power headroom report PHR configuration and a second PHR configuration to a terminal, wherein the first PHR configuration includes a first prohibition timer, and the second PHR configuration includes a threshold and a second prohibition timer; and In case that the PHR is triggered, receiving the PHR from the terminal, wherein the PHR is triggered when the power management maximum power reduction P-MPR value applied to meet the required value is greater than or equal to the threshold and the second prohibition timer is not running, In which, when the P field included in the PHR is set to 1, the field included in the PHR indicates the P-MPR value, and the length of the field is 2 bits.

11. The base station according to claim 10, in, The field indicates a range of P-MPR values; and In which, when the P field is set to 0, the reserved field is used.

12. The base station according to claim 10, wherein: In case the PHR is triggered, the second prohibit timer is started; and The PHR includes a single-entry PHR or a multi-entry PHR.

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