Communication method and device for reducing power consumption of power amplifier

Abstract

According to the present invention, a transmission device for reducing power consumption of a power amplifier may estimate a signal characteristic value corresponding to a peak-to-average power ratio for each of a plurality of OFDM symbols on the basis of signal power in a frequency domain. The transmission device may determine, on the basis of the estimated signal characteristic value, whether each OFDM symbol is in a powerless state or the estimated signal characteristic value is less than a preset reference value. The transmission device may control, on the basis of the determined result, whether to operate the power amplifier for each OFDM symbol. The transmission device may determine, on the basis of the determined result, whether to perform clipping and filtering on each of the OFDM symbols. The transmission device may determine, on the basis of the determined result, whether to perform digital pre-distortion on each of the OFDM symbols.

Description

Communication method and device for reducing power consumption of a power amplifier

[0001] The present specification relates to a communication method and apparatus for reducing the power consumption of a power amplifier included in a transmitting end of a wireless communication system, and more specifically, to a communication method and apparatus for reducing power consumption by selectively controlling the operation of a power amplifier and a transmission preprocessing block according to the signal characteristics at the symbol level in a base station, radio unit, or wireless transmitting device having an OFDM-based transmission structure.

[0002]

[0003] In wireless communication systems, particularly 4G, 5G, and next-generation mobile communication systems, transmission structures based on Orthogonal Frequency Division Multiplexing (OFDM) are widely used to support high data transmission rates and wide bandwidths. In these OFDM-based transmission structures, the signal's peak-to-average power ratio (PAPR) increases as multiple subcarriers are used simultaneously. Accordingly, power amplifiers included in the transmitter need to be designed to operate in the linear region.

[0004] Generally, power amplifiers operate with output back-off to maintain signal linearity, which can lead to a decrease in power efficiency. To compensate for this, transmission preprocessing techniques such as Clipping and Filtering (CFR) or Digital Pre-Distortion (DPD) may be applied at the transmitter to compensate for the non-linear characteristics of the power amplifier or reduce PAPR. However, these preprocessing techniques involve high computational complexity and are often executed continuously even when no signal is present or the power amplifier is operating sufficiently in the linear region, which can lead to unnecessary power consumption.

[0005] Furthermore, in wireless transmitters, power amplifiers often remain active even during time intervals or specific symbol intervals where user data is absent. In such structures, power amplifiers operate even in periods where signal amplification is not actually required, which can reduce the overall energy efficiency of the transmitter. Particularly in devices containing multiple transmission chains, such as base stations or radio units, this accumulated power consumption can lead to increased operating costs and overheating issues.

[0006] Meanwhile, although various attempts have been proposed to reduce power consumption by controlling the on / off state of power amplifiers, signal distortion or degradation of transmission quality may occur if the activation delay of the power amplifier or the processing delay occurring in the transmission path is not sufficiently considered. Furthermore, if the control of the power amplifier and the operation control of the transmission preprocessing block are not coordinated, the power saving effect may be limited or the system implementation may become complex.

[0007] Therefore, there is a need for a new communication method and device that can selectively control the operation of not only the power amplifier but also the transmission preprocessing block according to the signal characteristics and the actual requirements of the transmission section in an OFDM-based wireless transmission system, thereby reducing unnecessary power consumption while stably maintaining the quality of the transmitted signal.

[0008]

[0009] The objective of this specification to solve the above-mentioned problems is to reduce unnecessary power consumption of a power amplifier by selectively controlling the operation of the power amplifier by distinguishing between sections where signal amplification is actually required and sections where it is not at the transmitting end of a wireless communication system.

[0010] Another objective of this specification to solve the above-mentioned problems is to resolve the issue of unnecessary power consumption that occurs in OFDM-based transmission structures when the power amplifier and transmission preprocessing block operate continuously even in symbol intervals where user data is absent or signal power is low.

[0011] Another objective of the present specification to solve the above-mentioned problems is to provide a communication method and device capable of mitigating signal distortion or transmission quality degradation caused by activation delay and transmission path processing delay that may occur during the on / off control process of a power amplifier, and simultaneously achieving power saving and signal quality maintenance.

[0012] Another objective of the present specification to solve the above-mentioned problems is to reduce unnecessary computation and the resulting power consumption by controlling preprocessing functions, such as clipping and filtering (CFR) and digital pre-distortion (DPD) performed at the transmitting end, to be selectively performed according to signal characteristics.

[0013]

[0014] A communication method for reducing power consumption of a power amplifier according to an embodiment of the present specification for achieving the above objective can reduce power consumption of a power amplifier by estimating a signal characteristic value corresponding to the peak-to-average power ratio (PAPR) for each of a plurality of OFDM symbols based on signal power in the frequency domain, determining whether each OFDM symbol is in a no-power state or whether the estimated signal characteristic value is less than a preset reference value based on the estimated signal characteristic value, controlling whether to operate a power amplifier for each OFDM symbol based on the determination result, determining whether to perform clipping and filtering (CFR) for each OFDM symbol based on the determination result, determining whether to perform digital pre-distortion (DPD) for each OFDM symbol based on the determination result, and transmitting each OFDM symbol according to whether to operate the power amplifier, whether to perform CFR, and whether to perform DPD.

[0015] Here, the step of estimating a signal characteristic value corresponding to the PAPR can be performed by calculating the signal power in the frequency domain from the OFDM resource map or user plane U-plane IQ data transmitted to the radio unit, and estimating a virtual PAPR value for each OFDM symbol based on the calculated signal power in the frequency domain.

[0016] Here, the step of determining whether to perform CFR for each OFDM symbol can be performed by disabling the performance of the CFR preprocessing function for the corresponding OFDM symbol when the estimated virtual PAPR value is less than a preset CFR threshold, and enabling the performance of the CFR preprocessing function for the corresponding OFDM symbol when the estimated virtual PAPR value is greater than or equal to the CFR threshold.

[0017] Here, the step of determining whether to perform DPD for each OFDM symbol can be performed by predicting the probability that the input signal of the power amplifier is located in a linear or non-linear region based on the signal power in the frequency domain, deactivating the performance of the DPD preprocessing function for the corresponding OFDM symbol if the prediction result indicates a high probability that the input signal is located in a linear region, and enabling the performance of the DPD preprocessing function for the corresponding OFDM symbol if the prediction result indicates that the input signal is located in a non-linear region or entry into a non-linear region is expected.

[0018] Here, the step of controlling whether the power amplifier operates for each of the above OFDM symbols can be performed by determining whether the transmitted signal is active for each of the above OFDM symbols, classifying each of the above OFDM symbols as active symbols or inactive symbols according to the determination result, deactivating the operation of the power amplifier for the corresponding OFDM symbol when each of the above OFDM symbols is determined to be inactive symbols, and enabling the operation of the power amplifier for the corresponding OFDM symbol when each of the above OFDM symbols is determined to be active symbols.

[0019] Here, when each OFDM symbol is determined to be an inactive symbol, in the step of controlling whether the power amplifier operates, the step of determining whether to perform the CFR, and the step of determining whether to perform the DPD, it may be determined that the operation of the power amplifier, the execution of the CFR preprocessing function, and the execution of the DPD preprocessing function are all disabled for the corresponding OFDM symbol.

[0020] Here, the estimation of the signal characteristic value corresponding to the PAPR and the determination of the power-free state can be performed using a value obtained by accumulating or averaging the frequency domain signal power for a plurality of consecutive OFDM symbols.

[0021] Here, in determining whether to operate the power amplifier, CFR, and DPD based on the virtual PAPR value, the operating state of the power amplifier, CFR preprocessing function, and DPD preprocessing function can be controlled to change only when the changed state is maintained for a plurality of consecutive OFDM symbols, even when the virtual PAPR value changes to exceed or fall below a reference value.

[0022] Here, in determining whether to operate the power amplifier, CFR, and DPD based on the virtual PAPR value, preprocessing execution history information including at least one of the execution history of the CFR preprocessing function and the execution history of the DPD preprocessing function in previous OFDM symbols is obtained, a weight to be applied to the virtual PAPR value is calculated based on at least one of the execution frequency or execution duration included in the preprocessing execution history information, and the operation of the power amplifier, CFR preprocessing function, and DPD preprocessing function can be determined using the weighted virtual PAPR value reflecting the calculated weight.

[0023] Here, the step of estimating the signal characteristic value corresponding to the PAPR can be performed by further calculating a power distribution index indicating how the signal power calculated in the frequency domain is distributed among multiple subcarriers or resource blocks within an OFDM symbol, and correcting the virtual PAPR value or the signal characteristic value corresponding to the PAPR based on the power distribution index to determine whether the power amplifier, CFR preprocessing function, and DPD preprocessing function operate.

[0024] A communication device for reducing power consumption of a power amplifier according to another embodiment of the present specification for achieving the above objective includes a processor and a memory that stores at least one instruction executed by the processor, wherein the at least one instruction estimates a signal characteristic value corresponding to a peak-to-average power ratio (PAPR) for each of a plurality of OFDM symbols based on signal power in the frequency domain, determines whether each OFDM symbol is in a no-power state or whether the estimated signal characteristic value is less than a preset reference value based on the estimated signal characteristic value, controls whether to operate a power amplifier for each OFDM symbol based on the determination result, determines whether to perform clipping and filtering (CFR) for each OFDM symbol based on the determination result, determines whether to perform digital pre-distortion (DPD) for each OFDM symbol based on the determination result, and may be configured to transmit each OFDM symbol according to whether to operate the power amplifier, whether to perform CFR, and whether to perform DPD.

[0025] Here, the at least one command may be configured to calculate the signal power in the frequency domain from user plane U-plane IQ data transmitted to the OFDM resource map or radio unit, and to estimate a virtual PAPR value for each OFDM symbol based on the calculated signal power in the frequency domain.

[0026] Here, the at least one command may be configured to disable the performance of the CFR preprocessing function for the corresponding OFDM symbol when the estimated virtual PAPR value is less than a preset CFR threshold, and to enable the performance of the CFR preprocessing function for the corresponding OFDM symbol when the estimated virtual PAPR value is greater than or equal to the CFR threshold.

[0027] Here, the at least one command may be configured to predict the likelihood that the input signal of the power amplifier is located in a linear or non-linear region based on the signal power in the frequency domain, disable the execution of the DPD preprocessing function for the corresponding OFDM symbol if the likelihood that the input signal is located in the linear region is high, and enable the execution of the DPD preprocessing function for the corresponding OFDM symbol if the input signal is located in the non-linear region or entry into the non-linear region is expected.

[0028] Here, the at least one command may be configured to determine whether the transmission signal is active for each OFDM symbol, classify the OFDM symbol as an active symbol or an inactive symbol according to the determination result, disable the operation of the power amplifier for the inactive symbol, and enable the operation of the power amplifier for the active symbol.

[0029] Here, the at least one command may be configured to control the operation of the power amplifier, the execution of the CFR preprocessing function, and the execution of the DPD preprocessing function to be all disabled when the OFDM symbol is determined to be an inactive symbol.

[0030] Here, the at least one command may be configured to perform the estimation of a signal characteristic value corresponding to the PAPR and the determination of the no-power state using a value obtained by accumulating or averaging the frequency domain signal power for a plurality of consecutive OFDM symbols.

[0031] Here, the at least one command may be configured to control the operation state of the power amplifier, CFR preprocessing function, and DPD preprocessing function to change only when the change state is maintained for a plurality of consecutive OFDM symbols, even if the virtual PAPR value changes to exceed or fall below a reference value.

[0032] Here, the at least one command may be configured to acquire preprocessing execution history information including at least one of the execution history of the CFR preprocessing function and the execution history of the DPD preprocessing function in previous OFDM symbols, calculate a weight to be applied to the virtual PAPR value based on at least one of the execution frequency or execution duration included in the preprocessing execution history information, and determine whether to operate the power amplifier, the CFR preprocessing function, and the DPD preprocessing function using the weighted virtual PAPR value reflecting the calculated weight.

[0033] Here, the at least one command may be configured to further calculate a power distribution index indicating how signal power calculated in the frequency domain is distributed among multiple subcarriers or resource blocks within an OFDM symbol, and to determine whether to operate the power amplifier, CFR preprocessing function, and DPD preprocessing function by correcting the virtual PAPR value or the signal characteristic value corresponding to the PAPR based on the power distribution index.

[0034]

[0035] According to one embodiment of the present specification, by determining the presence of a signal on a symbol-by-symbol basis in an OFDM-based wireless transmission system and controlling the on / off of a power amplifier, unnecessary power consumption of the power amplifier occurring in sections where user data is not present can be effectively reduced. Through this, the average power consumption of the transmission device can be reduced and energy efficiency improved.

[0036] According to one embodiment of the present specification, by adjusting the timing of the power amplifier control signal in consideration of the processing delay occurring in the transmission path and the activation delay of the power amplifier, signal distortion or degradation of transmission quality can be prevented even during power saving operations. Accordingly, power saving and the linearity and stability of the transmission signal can be secured simultaneously.

[0037] According to one embodiment of the present specification, by selectively controlling whether to perform clipping and filtering (CFR) and digital pre-distortion (DPD) based on signal power information in the frequency domain, unnecessary operations can be omitted in sections where such pre-processing is not actually required. Through this, the amount of computation and power consumption across the entire transmission pre-processing block as well as the power amplifier can be further reduced.

[0038]

[0039] FIG. 1 is a block diagram showing the configuration of a communication device that reduces the power consumption of a power amplifier according to one embodiment of the present specification.

[0040] FIG. 2 is a diagram illustrating the overall transmission processing flow and symbol unit control structure of a communication device that reduces power consumption of a power amplifier according to one embodiment of the present specification.

[0041] FIG. 3 is a flowchart illustrating a communication method for reducing power consumption of a power amplifier according to one embodiment of the present specification.

[0042] FIG. 4 is a conceptual diagram illustrating the case where a virtual PAPR value estimated based on frequency domain signal power is greater than or equal to a system threshold value according to one embodiment of the present specification.

[0043] FIG. 5 is a conceptual diagram illustrating the case where a virtual PAPR value estimated based on frequency domain signal power is less than a system threshold value according to one embodiment of the present specification.

[0044]

[0045] As the present specification is susceptible to various modifications and may have various embodiments, specific embodiments are illustrated in the drawings and described in detail in the detailed description. However, this is not intended to limit the present specification to specific embodiments, and it should be understood that it includes all modifications, equivalents, and substitutions that fall within the spirit and scope of the present specification. Similar reference numerals have been used for similar components in the description of each drawing.

[0046] Terms such as first, second, A, B, etc., may be used to describe various components, but said components should not be limited by said terms. These terms are used solely for the purpose of distinguishing one component from another. For example, without departing from the scope of the rights of this specification, the first component may be named the second component, and similarly, the second component may be named the first component. The term "and / or" includes a combination of a plurality of related described items or any of a plurality of related described items.

[0047] When it is stated that one component is "connected" or "connected" to another component, it should be understood that while it may be directly connected or connected to that other component, there may also be other components in between. On the other hand, when it is stated that one component is "directly connected" or "directly connected" to another component, it should be understood that there are no other components in between.

[0048] The terms used in this application are used merely to describe specific embodiments and are not intended to limit this specification. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this application, terms such as "comprising" or "having" are intended to indicate the presence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0049] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which this specification pertains. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in this application.

[0050] Hereinafter, preferred embodiments of the present specification will be described in more detail with reference to the attached drawings. To facilitate overall understanding in describing the present specification, the same reference numerals are used for identical components in the drawings, and redundant descriptions of identical components are omitted.

[0051]

[0052] FIG. 1 is a block diagram showing the configuration of a communication device that reduces the power consumption of a power amplifier according to one embodiment of the present specification.

[0053] Referring to FIG. 1, a communication device (100) (hereinafter, a transmitting device (100)) that reduces the power consumption of a power amplifier may include a communication unit (110), a processor (120), a memory (130), a power amplifier (140), a clipping and filtering (CFR) processing unit (150), and a digital pre-distortion (DPD) processing unit (160). The processor may execute program instructions stored in the memory to estimate a virtual PAPR per OFDM symbol based on signal power in the frequency domain, and control the operation of the power amplifier, the CFR processing unit, and the DPD processing unit on a symbol-by-symbol basis based on the virtual PAPR. Only components related to the embodiment are shown in the transmitting device (100) of FIG. 1. Therefore, a person skilled in the art will understand that other general-purpose components may be included in addition to the components shown in FIG. 1.

[0054] The communication unit (110) can perform the function of receiving user plane (U-plane) IQ data from a higher device or network element, or outputting a transmission signal processed by the transmission device (100) to the outside. The communication unit (110) can be connected to a digital unit, distributed unit, or central unit of a base station via a wired or wireless interface and can transmit a frequency domain signal for OFDM-based transmission processing to a processor (120).

[0055]

[0056] The processor (120) is a component that controls the overall operation of the transmitting device (100) and can perform the operation of the present invention by executing program instructions stored in memory (130). The processor (120) can calculate signal power in the frequency domain and, based on the signal power in the frequency domain, estimate a signal characteristic value corresponding to the peak-to-average power ratio (PAPR) for each of a plurality of OFDM symbols, for example, a virtual PAPR value. In addition, the processor (120) can control the operation or execution of the power amplifier (140), CFR processing unit (150), and DPD processing unit (160) on a symbol-by-symbol basis, based on the estimated signal characteristic value and the result of determining whether the OFDM symbol is active.

[0057]

[0058] The memory (130) is a storage means for storing program code, control parameters, and processing data required for the operation of the transmitting device (100). The memory (130) can store reference values ​​used for virtual PAPR estimation, CFR threshold values, DPD threshold values, frequency domain power information per OFDM symbol, and CFR or DPD preprocessing execution history information, and can support the processor (120) in performing cumulative or history-based judgments across multiple OFDM symbols.

[0059]

[0060] The power amplifier (140) is a component that amplifies the transmission signal to enable wireless transmission. The processor (120) can perform micro-DTX-based power saving control by deactivating the operation of the power amplifier (140) when the OFDM symbol is determined to be an inactive symbol, and by activating the power amplifier (140) when the OFDM symbol is determined to be an active symbol.

[0061]

[0062] A clipping and filtering (CFR) processing unit (150) can perform a preprocessing function to limit peak components of a transmitted signal. A processor (120) can control the execution of the CFR processing unit (150) for the corresponding OFDM symbol to be disabled if the estimated virtual PAPR value is below a preset CFR threshold, and to enable the CFR processing unit (150) for the corresponding OFDM symbol if the virtual PAPR value is above the CFR threshold.

[0063]

[0064] The digital pre-distortion (DPD) processing unit (160) can perform a pre-processing function to compensate for the non-linear characteristics of the power amplifier (140). The processor (120) can predict the likelihood that the input signal of the power amplifier (140) is located in a linear or non-linear region based on frequency domain signal power or a virtual PAPR value, and determine whether to perform the DPD processing unit (160) for the corresponding OFDM symbol according to the prediction result.

[0065] The processor (120) may be implemented using at least one of ASICs (application specific integrated circuits), DSPs (digital signal processors), DSPDs (digital signal processing devices), PLDs (programmable logic devices), FPGAs (field programmable gate arrays), controllers, microcontrollers, microprocessors, and other electrical units for performing functions.

[0066] The memory (130) can be implemented as a non-transient computer-readable medium and can include both volatile memory (RAM) and non-volatile memory (ROM, flash memory, hard disk, etc.).

[0067] The memory (230) may include RAM (random access memory), such as DRAM (dynamic random access memory) and SRAM (static random access memory), ROM (read-only memory), EEPROM (electrically erasable programmable read-only memory), CD-ROM, Blu-ray or other optical disc storage, HDD (hard disk drive), SSD (solid state drive), or flash memory.

[0068] The memory (130) may store at least one instruction executed through the processor (120). The at least one instruction may be configured to estimate a signal characteristic value corresponding to the peak-to-average power ratio (PAPR) for each of a plurality of OFDM symbols based on signal power in the frequency domain, determine whether each OFDM symbol is in a no-power state or whether the estimated signal characteristic value is less than a preset reference value based on the estimated signal characteristic value, control whether a power amplifier is operated for each OFDM symbol based on the determination result, determine whether clipping and filtering (CFR) is performed for each OFDM symbol based on the determination result, determine whether digital pre-distortion (DPD) is performed for each OFDM symbol based on the determination result, and transmit each OFDM symbol according to whether the power amplifier is operated, whether the CFR is performed, and whether the DPD is performed.

[0069] Here, the at least one command may be configured to calculate the signal power in the frequency domain from user plane U-plane IQ data transmitted to the OFDM resource map or radio unit, and to estimate a virtual PAPR value for each OFDM symbol based on the calculated signal power in the frequency domain.

[0070] Here, the at least one command may be configured to disable the performance of the CFR preprocessing function for the corresponding OFDM symbol when the estimated virtual PAPR value is less than a preset CFR threshold, and to enable the performance of the CFR preprocessing function for the corresponding OFDM symbol when the estimated virtual PAPR value is greater than or equal to the CFR threshold.

[0071] Here, the at least one command may be configured to predict the likelihood that the input signal of the power amplifier is located in a linear or non-linear region based on the signal power in the frequency domain, disable the execution of the DPD preprocessing function for the corresponding OFDM symbol if the likelihood that the input signal is located in the linear region is high, and enable the execution of the DPD preprocessing function for the corresponding OFDM symbol if the input signal is located in the non-linear region or entry into the non-linear region is expected.

[0072] Here, the at least one command may be configured to determine whether the transmission signal is active for each OFDM symbol, classify the OFDM symbol as an active symbol or an inactive symbol according to the determination result, disable the operation of the power amplifier for the inactive symbol, and enable the operation of the power amplifier for the active symbol.

[0073] Here, the at least one command may be configured to control the operation of the power amplifier, the execution of the CFR preprocessing function, and the execution of the DPD preprocessing function to be all disabled when the OFDM symbol is determined to be an inactive symbol.

[0074] Here, the at least one command may be configured to perform the estimation of a signal characteristic value corresponding to the PAPR and the determination of the no-power state using a value obtained by accumulating or averaging the frequency domain signal power for a plurality of consecutive OFDM symbols.

[0075] Here, the at least one command may be configured to control the operation state of the power amplifier, CFR preprocessing function, and DPD preprocessing function to change only when the change state is maintained for a plurality of consecutive OFDM symbols, even if the virtual PAPR value changes to exceed or fall below a reference value.

[0076] Here, the at least one command may be configured to acquire preprocessing execution history information including at least one of the execution history of the CFR preprocessing function and the execution history of the DPD preprocessing function in previous OFDM symbols, calculate a weight to be applied to the virtual PAPR value based on at least one of the execution frequency or execution duration included in the preprocessing execution history information, and determine whether to operate the power amplifier, the CFR preprocessing function, and the DPD preprocessing function using the weighted virtual PAPR value reflecting the calculated weight.

[0077] Here, the at least one command may be configured to further calculate a power distribution index indicating how signal power calculated in the frequency domain is distributed among multiple subcarriers or resource blocks within an OFDM symbol, and to determine whether to operate the power amplifier, CFR preprocessing function, and DPD preprocessing function by correcting the virtual PAPR value or the signal characteristic value corresponding to the PAPR based on the power distribution index.

[0078]

[0079] FIG. 2 is a diagram illustrating the overall transmission processing flow and symbol unit control structure of a communication device that reduces power consumption of a power amplifier according to one embodiment of the present specification.

[0080] Referring to FIG. 2, the transmitting device analyzes the signal power in the frequency domain for an OFDM-based transmitting signal, estimates a virtual PAPR value for each OFDM symbol based on this, and then selectively controls the operation of clipping and filtering (CFR), digital pre-distortion (DPD), and power amplifier on a symbol-by-symbol basis according to the estimation result.

[0081] Specifically, the transmitting device receives user plane (U-plane) IQ data from an upper layer or upper device, and the IQ data can be processed in the frequency domain at the level of an OFDM resource map or a radio unit (RU). The transmitting device calculates signal power at the level of a subcarrier or resource block from the frequency domain IQ data and can estimate a virtual PAPR value for each OFDM symbol using the calculated frequency domain signal power.

[0082] As illustrated in FIG. 2, the virtual PAPR value can be used as an indicator to predict the probability of a time-domain peak occurring using only frequency-domain power information in a step prior to directly calculating the actual PAPR in the time domain. The transmitting device can determine whether the virtual PAPR value is greater than or equal to a preset reference value or threshold value, and, based on the result of the determination, determine whether to perform CFR preprocessing and DPD preprocessing functions for the corresponding OFDM symbol.

[0083] In addition, the transmitting device determines the activity status of each OFDM symbol and can disable the operation of the power amplifier for inactive symbols determined to be in a state where no transmission signal is present or there is no power. Conversely, if a symbol is determined to be active, the power amplifier can be activated to ensure that the transmission signal is amplified normally. This symbol-level on / off control of the power amplifier can be performed in conjunction with the micro-DTX structure.

[0084] In the structure illustrated in FIG. 2, the determination of whether to perform virtual PAPR estimation and preprocessing in the frequency domain, and delay correction considering the temporal alignment between CFR, DPD, and power amplifier operations actually performed in the time domain and RF domain can be performed together. That is, even if the transmitting device decides not to perform CFR or DPD for a specific OFDM symbol in the frequency domain, it can correct the delay of the control signal so that the decision is applied to the OFDM symbol that exactly corresponds to the actual time domain signal and RF output stage.

[0085] The transmitting device illustrated in Fig. 2 can effectively reduce the power consumption of the entire transmitting chain by integrating frequency domain power analysis, virtual PAPR estimation, symbol-unit preprocessing control, and micro-DTX-based power amplifier control, thereby omitting unnecessary CFR and DPD preprocessing operations and minimizing the operating time of the power amplifier.

[0086]

[0087] FIG. 3 is a flowchart illustrating a communication method for reducing power consumption of a power amplifier according to one embodiment of the present specification.

[0088] Referring to FIG. 3, the transmitting device can estimate PAPR (S300). For example, the transmitting device can estimate a signal characteristic value corresponding to the Peak-to-Average Power Ratio (PAPR) for each of the multiple Orthogonal Frequency Division Multiplexing (OFDM) symbols based on signal power in the frequency domain.

[0089] A communication method for reducing power consumption of a power amplifier according to one embodiment of the present specification may be performed by a transmitting device. The transmitting device may include a communication unit, a processor, a memory, a power amplifier, a clipping and filtering (CFR) processing unit, and a digital pre-distortion (DPD) processing unit, and may reduce power consumption by selectively controlling the operation of the power amplifier and the pre-processing function on a symbol-by-symbol basis for an Orthogonal Frequency Division Multiplexing (OFDM) based transmission signal.

[0090] According to one embodiment of the present specification, a transmitting device can estimate a signal characteristic value corresponding to the Peak to Average Power Ratio (PAPR) for each of a plurality of OFDM symbols based on signal power in the frequency domain. Here, the signal characteristic value is a value for predicting the probability of a time-domain peak occurring without directly calculating the actual PAPR in the time domain, and can be estimated in the form of a virtual PAPR value using signal power calculated from U-plane IQ data in the frequency domain.

[0091] The transmitting device can determine whether there is no power or a low PAPR (S310). For example, the transmitting device can determine whether each OFDM symbol is in a no-power state or whether the estimated signal characteristic value is less than a preset reference value based on the estimated signal characteristic value.

[0092] Here, the no-power state may include a state where there is no actual transmission signal for the corresponding OFDM symbol or the transmission power is extremely low, and the reference value may be set as a threshold value to determine whether to perform CFR or DPD preprocessing.

[0093] The transmitting device can control the operation of the power amplifier (S320). For example, the transmitting device can control whether to operate the power amplifier for each OFDM symbol based on the above judgment result.

[0094] For example, if the above OFDM symbol is determined to be in a no-power state, the transmitting device can perform micro-DTX-based power saving control by deactivating the operation of the power amplifier for the said OFDM symbol, and if the above OFDM symbol is not in a no-power state, it can control the transmission signal to be amplified normally by activating the power amplifier.

[0095] The transmitting device can determine whether to perform CFR (S330). For example, the transmitting device can determine whether to perform Clipping and Filtering (CFR) for each OFDM symbol based on the result of the above determination.

[0096] The transmitting device can determine whether to perform CFR for each OFDM symbol based on the same judgment result. For example, if the estimated signal characteristic value is less than a preset threshold value, the performance of the CFR preprocessing function for the corresponding OFDM symbol can be disabled to omit unnecessary clipping and filtering operations, and if the signal characteristic value is greater than or equal to the threshold value, the CFR preprocessing function can be enabled to limit peak components in the time domain.

[0097] The transmitting device can determine whether to perform DPD (S340). For example, the transmitting device can determine whether to perform Digital Pre-Distortion (DPD) for each OFDM symbol based on the result of the above determination.

[0098] The transmitting device can predict the likelihood that the input signal of the power amplifier is located in a linear or non-linear region using the frequency domain signal power or the estimated signal characteristic value, and can disable the DPD preprocessing function when there is a high likelihood that the input signal is located in a linear region, and enable the DPD preprocessing function when it is located in a non-linear region or when entry into a non-linear region is expected.

[0099]

[0100] FIG. 4 is a conceptual diagram illustrating the case where a virtual PAPR value estimated based on frequency domain signal power is greater than or equal to a system threshold value according to one embodiment of the present specification.

[0101] Referring to FIG. 4, a case is illustrated in which a virtual PAPR value is estimated to be relatively large based on the average power (Frequency Domain RMS Power) calculated in the frequency domain. In such a case, the peak power in the time domain increases, and there is a high probability that the input signal of the power amplifier will be located in an AM-AM nonlinear section or an AM-PM nonlinear section, or enter such a nonlinear section. If the transmitting device determines that the virtual PAPR value is greater than or equal to a preset system threshold, it can control the power amplifier to compensate for nonlinear distortion by activating a digital pre-distortion (DPD) preprocessing function for the corresponding OFDM symbol, and can also perform clipping and filtering (CFR) preprocessing functions as needed.

[0102] That is, Figure 4 conceptually illustrates an operational state in which a high probability of a time-domain peak occurring is predicted using only frequency-domain power information, and a pre-processing function is preemptively performed accordingly.

[0103] FIG. 5 is a conceptual diagram illustrating the case where a virtual PAPR value estimated based on frequency domain signal power is less than a system threshold value according to one embodiment of the present specification.

[0104] Referring to FIG. 5, a case is illustrated in which the virtual PAPR value is estimated to be relatively small based on the average power calculated in the frequency domain. In this case, the peak power in the time domain is likely to remain within the linear region of the power amplifier, so the likelihood of non-linear distortion occurring in the power amplifier may be low. When the transmitting device determines that the virtual PAPR value is below a system threshold, it can omit unnecessary preprocessing operations by controlling the digital pre-distortion (DPD) preprocessing function for the corresponding OFDM symbol and also not performing clipping and filtering (CFR) preprocessing functions.

[0105] That is, Figure 5 conceptually illustrates an operating state in which a case with a low probability of time-domain peak occurrence is identified through frequency-domain power-based virtual PAPR estimation, and the power consumption of the transmitting device is reduced by omitting preprocessing functions.

[0106]

[0107] Referring again to FIG. 3, the transmitting device can transmit OFDM symbols (S350). For example, the transmitting device can transmit each OFDM symbol depending on whether the power amplifier is operating, whether the CFR is being performed, and whether the DPD is being performed.

[0108] The transmitting device can effectively reduce the power consumption of the entire transmission chain by minimizing unnecessary preprocessing operations and power amplifier operations through signal characteristic value estimation based on frequency domain signal power and symbol-level preprocessing and power amplifier control using this.

[0109] According to one embodiment of the present specification, in a communication method for reducing the power consumption of a power amplifier, the step of estimating a signal characteristic value corresponding to PAPR can be performed using signal power in the frequency domain. More specifically, a transmitting device can calculate signal power in the frequency domain from an OFDM resource map or user plane (U-plane) IQ data transmitted to a radio unit. Here, the signal power in the frequency domain may include at least one of power values ​​in subcarrier units, resource block units, or OFDM symbol units.

[0110] According to one embodiment of the present specification, a transmitting device can estimate a virtual PAPR value for each OFDM symbol based on the calculated signal power in the frequency domain. The virtual PAPR value is a value for predicting the probability of a time-domain peak occurring without directly calculating the actual PAPR in the time domain, and can be calculated using the frequency domain power distribution, average power, or the relationship between maximum power and average power.

[0111] In the signal characteristic value estimation step according to one embodiment of the present specification, the probability of peak occurrence for each OFDM symbol can be determined in advance using only the frequency domain signal power in a step prior to time domain conversion or IFFT execution. Accordingly, the transmitting device can determine whether to perform CFR or DPD preprocessing functions in a subsequent step at an earlier point in time, and by avoiding unnecessary time domain operations, the amount of computation and power consumption in the overall transmission process can be reduced.

[0112] According to one embodiment of the present specification, in a communication method for reducing the power consumption of a power amplifier, the step of determining whether to perform clipping and filtering (CFR) for each OFDM symbol can be performed using the estimated virtual PAPR value. The transmitting device can determine whether the estimated virtual PAPR value is less than a preset CFR threshold based on the frequency domain signal power.

[0113] According to one embodiment of the present specification, if the virtual PAPR value is determined to be less than the CFR threshold, the transmitting device may disable the performance of the CFR preprocessing function for the corresponding OFDM symbol. In this case, since the probability of signal peak occurrence in the time domain is predicted to be low, the consumption of computational resources and power consumption can be reduced by omitting unnecessary clipping and filtering operations.

[0114] On the other hand, if the virtual PAPR value is determined to be greater than or equal to the CFR threshold, the transmitting device may enable a CFR preprocessing function for the corresponding OFDM symbol. In this case, since it is predicted that there is a high probability of a signal peak occurring in the time domain, distortion in the power amplifier can be mitigated by limiting the peak component of the signal through clipping and filtering.

[0115] Unlike a method in which the determination of whether to perform CFR according to one embodiment of the present specification determines whether to perform CFR after calculating the actual PAPR in the time domain, the step of determining whether to perform CFR can predetermine whether to perform the CFR preprocessing function using a virtual PAPR value estimated in the frequency domain. Accordingly, since the operation can be completely omitted for OFDM symbols for which the CFR preprocessing function is unnecessary, the effect of reducing the amount of computation of the entire transmission chain and reducing the power consumption of the power amplifier can be achieved simultaneously.

[0116] According to one embodiment of the present specification, in a communication method for reducing the power consumption of a power amplifier, the step of determining whether to perform Digital Pre-Distortion (DPD) for each OFDM symbol may be performed using signal power calculated in the frequency domain or the estimated virtual PAPR value. Based on the frequency domain signal power or the virtual PAPR value, the transmitting device may predict the possibility that the input signal of the power amplifier is located in a linear region or is located in a non-linear region or enters such region.

[0117] According to one embodiment of the present specification, the transmitting device may disable the performance of a digital pre-distortion preprocessing function for the corresponding OFDM symbol when the prediction result indicates that the input signal of the power amplifier is likely to be located in the linear region. In this case, since it is determined that the probability of non-linear distortion occurring in the power amplifier is low, the consumption of computational resources and power consumption can be reduced by omitting unnecessary DPD operations.

[0118] On the other hand, if the input signal of the power amplifier is located in a nonlinear region or is expected to enter a nonlinear region based on the above prediction results, the transmitting device may activate a digital pre-distortion preprocessing function for the corresponding OFDM symbol. In this case, the linearity of the transmitted signal can be maintained by compensating in advance for nonlinear distortion caused by the AM-AM and AM-PM characteristics of the power amplifier through the DPD preprocessing function.

[0119] Unlike a method that compensates for non-linear distortion of a power amplifier based on a time-domain signal, the step of determining whether to perform DPD according to one embodiment of the present specification predicts the operating region of the power amplifier in advance using frequency-domain signal power or a virtual PAPR value, and can selectively control whether to perform the DPD preprocessing function on a symbol-by-symbol basis based on this. Accordingly, since the operation can be omitted for OFDM symbols for which the DPD preprocessing function is unnecessary, the amount of computation in the overall transmission process can be reduced, and the power consumption of the power amplifier can be reduced more effectively.

[0120] According to one embodiment of the present specification, in a communication method for reducing the power consumption of a power amplifier, the step of controlling whether the power amplifier operates for each OFDM symbol may be performed based on whether the transmission signal is active. The transmitting device can distinguish whether the OFDM symbol is an active symbol or an inactive symbol by determining whether a transmission signal is present for each OFDM symbol or whether transmission power is significantly applied.

[0121] According to one embodiment of the present specification, the inactive symbol may include an OFDM symbol that does not contain user data or has little to no transmission power applied, and may include, for example, a symbol that is omitted from transmission in a micro-DTX structure. When each OFDM symbol is determined to be an inactive symbol, the transmitting device can prevent unnecessary power consumption by disabling the operation of the power amplifier for the corresponding OFDM symbol.

[0122] On the other hand, when the transmitting device determines that each of the above OFDM symbols is an active symbol, it can control the power amplifier for the corresponding OFDM symbol to ensure that the transmission signal is amplified and transmitted normally. In this case, the activation of the power amplifier can be performed in accordance with the transmission timing of the corresponding OFDM symbol, and can be controlled by considering the temporal alignment between the operation time of the power amplifier and the actual RF transmission time.

[0123] A power amplifier operation control step according to one embodiment of the present specification may be performed based on determining activity at the OFDM symbol level, thereby enabling the power amplifier to be controlled to operate only during the interval where transmission is actually required. Accordingly, a micro-DTX-based power saving effect can be achieved by stopping the operation of the power amplifier during consecutive inactive symbol intervals, and the average power consumption of the entire transmitting device can be effectively reduced.

[0124] According to one embodiment of the present specification, in a communication method for reducing the power consumption of a power amplifier, when each OFDM symbol is determined to be an inactive symbol, the steps of controlling whether to operate the power amplifier, determining whether to perform clipping and filtering (CFR), and determining whether to perform digital pre-distortion (DPD) can be performed together based on the same determination result. That is, the transmitting device can determine the operating status of the power amplifier, the CFR preprocessing function, and the DPD preprocessing function in conjunction by using the result of determining whether each OFDM symbol is active as a common control criterion.

[0125] According to one embodiment of the present specification, when each OFDM symbol is determined to be an inactive symbol, the transmitting device may disable the operation of the power amplifier for the corresponding OFDM symbol, and simultaneously disable the execution of the CFR preprocessing function and the DPD preprocessing function. In this case, since the power amplifier and the baseband preprocessing operation can be omitted together for the section where the transmission signal is not actually transmitted or transmission power is hardly applied, the power consumption in the entire transmission chain can be reduced more effectively.

[0126] In addition, according to one embodiment of the present specification, such control can be performed on a per-OFDM symbol basis, and for consecutive periods of inactive symbols, the power amplifier, CFR preprocessing function, and DPD preprocessing function can all be maintained in a deactivated state. Accordingly, an integrated power saving structure combining micro-DTX-based power amplifier on / off control and frequency domain power-based preprocessing control can be implemented.

[0127] According to one embodiment of the present specification, by not limiting the operation control of the power amplifier alone but by linking and controlling the entire transmission preprocessing block, including CFR and DPD preprocessing functions, on a symbol-by-symbol basis, unnecessary computation and power consumption can be minimized and the energy efficiency of the transmission device can be further improved.

[0128] According to one embodiment of the present specification, in a communication method for reducing the power consumption of a power amplifier, the estimation of a signal characteristic value corresponding to PAPR and the determination of the power-free state of each OFDM symbol are not limited to a method using only the frequency domain signal power for a single OFDM symbol, but can be performed using a value obtained by accumulating or averaging the frequency domain signal power for a plurality of consecutive OFDM symbols. The transmitting device can mitigate judgment errors caused by instantaneous power fluctuations or noise by processing the frequency domain signal power calculated for a consecutive OFDM symbol interval in the form of an accumulation, moving average, or weighted average.

[0129] According to one embodiment of the present specification, by utilizing frequency domain signal power for a plurality of OFDM symbols as described above, the stability of the virtual PAPR value estimated for each OFDM symbol can be improved. That is, the transmitting device can estimate a more reliable signal characteristic value by reflecting power characteristics over a certain time interval, without relying on power peaks or low-power intervals that occur temporarily in a single symbol.

[0130] Additionally, according to one embodiment of the present specification, the accumulated or averaged frequency domain signal power may also be used to determine a no-power state. For example, if the accumulated or averaged signal power for a series of OFDM symbols is maintained below a preset threshold, the transmitting device may determine that the corresponding OFDM symbol or the corresponding symbol interval is in a no-power state.

[0131] By utilizing the temporal accumulation characteristics of frequency domain signal power, a temporal context can be introduced into symbol-unit judgment, and as a result, the operation or execution of the power amplifier, clipping and filtering processing unit, and digital pre-distortion processing unit can be controlled more stably. Accordingly, unnecessary preprocessing operations or frequent on / off switching of the power amplifier can be prevented, and control stability of the transmitting device can be ensured while the power consumption of the entire transmission chain can be reduced more effectively.

[0132] According to one embodiment of the present specification, in determining whether to operate or perform a power amplifier, a clipping and filtering processing unit, and a digital pre-distortion processing unit using a virtual PAPR value estimated based on frequency domain signal power, the determination may not be limited to a manner that immediately responds to the result of a judgment in a single OFDM symbol. The transmitting device may further determine whether the changed state is maintained for a plurality of consecutive OFDM symbols even when the virtual PAPR value changes to exceed or fall below a preset reference value.

[0133] Specifically, the transmitting device may change the operating state of the power amplifier, clipping and filtering processing unit, and digital pre-distortion processing unit only when the virtual PAPR value exceeds a reference value and is maintained over a number of consecutive OFDM symbols. Conversely, even if the virtual PAPR value temporarily exceeds or falls below the reference value, if the state is not maintained for a preset number of symbols or time interval, the existing operating state may be maintained.

[0134] According to this control method, even if the virtual PAPR value frequently changes near the threshold due to instantaneous fluctuations in frequency domain signal power or noise, it is possible to prevent the power amplifier or preprocessing function from repeatedly switching on and off excessively. As a result, the operational stability of the transmitting device is improved, and the generation of unnecessary control signals and computational overhead can be reduced.

[0135] Furthermore, this control stabilization structure can operate even more effectively when combined with the power amplifier's micro-DTX-based on / off control. By controlling the power amplifier and preprocessing functions to be deactivated only when a continuous period of inactivity or a low virtual PAPR state is maintained for a certain duration, the average power consumption of the transmitting device can be stably reduced.

[0136] According to one embodiment of the present specification, in determining whether to operate or perform a power amplifier, a clipping and filtering processing unit, and a digital pre-distortion processing unit using a virtual PAPR value estimated based on frequency domain signal power, the transmitting device may consider not only the signal characteristic value of the current OFDM symbol but also the history of pre-processing in previous OFDM symbols. Here, the history of pre-processing may include at least one of whether the clipping and filtering processing unit was performed on past OFDM symbols, whether the digital pre-distortion processing unit was performed, or the frequency of execution or duration of execution of each pre-processing function.

[0137] Specifically, the transmitting device can acquire preprocessing history information from previous OFDM symbols and calculate weights to be applied to the virtual PAPR value based on said preprocessing history information. For example, if the CFR or DPD preprocessing function has been performed frequently during a recent period, the weights can be increased to make a more conservative judgment even for the same virtual PAPR value. Conversely, if the frequency of preprocessing function execution is low or if it has not been performed for a prolonged period, the weights applied to the virtual PAPR value can be decreased to control the judgment to make a more lenient one.

[0138] In addition, the above weights may be adjusted according to a preset policy, power saving target, or operating status of the transmitting device, in addition to the history of preprocessing execution. The transmitting device may determine whether to operate or perform the power amplifier, clipping and filtering processing unit, and digital pre-distortion processing unit by using a weighted virtual PAPR value that reflects the weights calculated as above.

[0139] According to one embodiment of the present specification, the process of estimating a virtual PAPR value using signal power in the frequency domain may not be limited to considering only the absolute magnitude of the signal power. By further analyzing how the frequency domain signal power is distributed in units of subcarriers or resource blocks within an OFDM symbol, the transmitting device can more precisely predict the probability of peak occurrence in the time domain.

[0140] Specifically, the transmitting device can calculate a power distribution index indicating whether the signal power calculated in the frequency domain is concentrated in a specific subcarrier or a specific resource block, or whether the power is distributed relatively evenly. The power distribution index can be expressed in a form such as, for example, the degree of bias, dispersion, concentration, or the ratio of the upper power component, and such an index may have a close correlation with the probability of peak occurrence in the time domain.

[0141] According to one embodiment of the present specification, a transmitting device may calculate a corrected signal characteristic value by reflecting the power distribution indicator in the virtual PAPR value or in the process of estimating the virtual PAPR value. For example, even if the average power is the same, if the power in the frequency domain is concentrated in a specific subcarrier or resource block, the virtual PAPR value may be corrected upward by determining that the probability of peak occurrence in the time domain is higher. Conversely, if the power in the frequency domain is distributed relatively evenly, the virtual PAPR value may be corrected downward by determining that the probability of peak occurrence in the time domain is low.

[0142] The corrected signal characteristic values ​​can be used to determine whether to operate or perform the power amplifier, clipping and filtering processing unit, and digital pre-distortion processing unit. Accordingly, control that more accurately reflects the possibility of time-domain peak occurrence compared to a simple power magnitude-based judgment can be achieved.

[0143] In addition, the signal characteristic value correction method considering frequency domain power distribution is a configuration that extends the basic concept of this specification of predicting time domain characteristics using only frequency domain information, and can improve judgment accuracy without additional time domain computation. Accordingly, the transmitting device can minimize the increase in computational load while controlling the operation of the preprocessing function and power amplifier more precisely, and can effectively reduce the power consumption of the entire transmission chain.

[0144]

[0145] The operation according to the embodiments of this specification may be implemented as a computer-readable program or code on a computer-readable recording medium. A computer-readable recording medium includes all types of recording devices in which data that can be read by a computer system is stored. Additionally, a computer-readable recording medium may be distributed across networked computer systems, allowing computer-readable programs or code to be stored and executed in a distributed manner.

[0146] When the embodiment is implemented in software, the above-described technique may be implemented as a module (process, function, etc.) that performs the above-described function. The module may be stored in memory and executed by a processor. The memory may be located inside or outside the processor and may be connected to the processor by various well-known means.

[0147] In addition, computer-readable recording media may include hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, and flash memory. Program instructions may include machine code, such as that generated by a compiler, as well as high-level language code that can be executed by a computer using an interpreter, etc.

[0148] Some aspects of this specification have been described in the context of a device, but may also be described according to a corresponding method, wherein a block or device corresponds to a method step or a feature of a method step. Similarly, aspects described in the context of a method may also be described according to a corresponding block or item or a feature of a corresponding device. Some or all of the method steps may be performed by (or using) a hardware device, such as, for example, a microprocessor, a programmable computer, or an electronic circuit. In some embodiments, one or more of the most important method steps may be performed by such a device.

[0149] In the embodiments, a programmable logic device (e.g., a field-programmable gate array) may be used to perform some or all of the functions of the methods described herein. In the embodiments, the field-programmable gate array may operate with a microprocessor to perform one of the methods described herein. Generally, it is preferable that the methods be performed by some hardware device.

[0150] Although the foregoing has been described with reference to preferred embodiments of this specification, those skilled in the art will understand that various modifications and changes can be made to this specification without departing from the spirit and scope of the specification as set forth in the following claims.

Claims

1. A communication method for reducing the power consumption of a power amplifier performed by at least one transmitting device, A step of estimating a signal characteristic value corresponding to the Peak-to-Average Power Ratio (PAPR) for each of a plurality of Orthogonal Frequency Division Multiplexing (OFDM) symbols based on signal power in the frequency domain; A step of determining, based on the estimated signal characteristic value, whether each OFDM symbol is in a power-free state or whether the estimated signal characteristic value is less than a preset reference value; A step of controlling whether to operate a power amplifier for each OFDM symbol based on the above judgment result; A step of determining whether to perform Clipping and Filtering (CFR) for each OFDM symbol based on the above judgment result; A step of determining whether to perform Digital Pre-Distortion (DPD) for each OFDM symbol based on the above judgment result; and A step of transmitting each OFDM symbol according to whether the power amplifier is operated, whether the CFR is performed, and whether the DPD is performed, A communication method that reduces the power consumption of a power amplifier.

2. In Claim 1, The step of estimating the signal characteristic value corresponding to the above PAPR is, A step of calculating signal power in the frequency domain from an OFDM resource map or user plane (U-plane) IQ data transmitted to a radio unit (RU); and A step comprising estimating a virtual PAPR value for each OFDM symbol based on the signal power in the frequency domain calculated above, A communication method that reduces the power consumption of a power amplifier.

3. In Claim 2, The step of determining whether to perform CFR for each of the above OFDM symbols is, If the above estimated virtual PAPR value is less than a preset CFR threshold, the execution of the CFR preprocessing function for the corresponding OFDM symbol is disabled, and A step comprising enabling the execution of a CFR preprocessing function for the corresponding OFDM symbol when the estimated virtual PAPR value is greater than or equal to the CFR threshold value, A communication method that reduces the power consumption of a power amplifier.

4. In Claim 1, The step of determining whether to perform DPD for each of the above OFDM symbols is: A step of predicting the likelihood that the input signal of a power amplifier (HPA) is located in a linear or non-linear region based on the signal power in the frequency domain; and Based on the above prediction result, if there is a high probability that the input signal is located in the linear region, the execution of the DPD preprocessing function for the corresponding OFDM symbol is disabled, and A step comprising, if, based on the above prediction result, the input signal is located in a non-linear region or entry into a non-linear region is expected, enabling the execution of a DPD preprocessing function for the corresponding OFDM symbol. A communication method that reduces the power consumption of a power amplifier.

5. In Claim 1, The step of controlling whether the power amplifier operates for each of the above OFDM symbols is: A step of determining whether the transmission signal is active for each of the above OFDM symbols; A step of classifying each OFDM symbol into an active symbol or a dormant symbol according to the above judgment result; and If each of the above OFDM symbols is determined to be an inactive symbol, the operation of the power amplifier for the corresponding OFDM symbol is disabled, and A step comprising activating the operation of a power amplifier for a corresponding OFDM symbol when each of the above OFDM symbols is determined to be an active symbol, A communication method that reduces the power consumption of a power amplifier.

6. In Claim 5, If each of the above OFDM symbols is determined to be an inactive symbol, In the step of controlling whether the power amplifier operates, the step of determining whether to perform the CFR, and the step of determining whether to perform the DPD, the operation of the power amplifier, the execution of the CFR preprocessing function, and the execution of the DPD preprocessing function are all controlled to be disabled for the corresponding OFDM symbol, and Characterized by controlling the operation of the power amplifier, the execution of the CFR preprocessing function, and the execution of the DPD preprocessing function to be all activated for the corresponding OFDM symbol when each of the above OFDM symbols is determined to be an active symbol. A communication method that reduces the power consumption of a power amplifier.

7. In Claim 1, The step of estimating the signal characteristic value corresponding to the above PAPR is, A signal power in the frequency domain is calculated from U-plane IQ data transmitted to an OFDM resource map or a radio unit (RU), wherein the signal power in the frequency domain includes at least one of subcarrier unit power, resource block unit power, and OFDM symbol unit average power. A virtual PAPR value for each OFDM symbol is estimated based on the signal power in the frequency domain calculated above, wherein the virtual PAPR value is calculated using accumulated, averaged, or weighted averaged power information for a plurality of consecutive OFDM symbols. The method further includes the step of determining the virtual PAPR value as a valid estimated value only when the variation of the virtual PAPR value is below a preset variation threshold. A communication method that reduces the power consumption of a power amplifier.

8. In Claim 7, In determining whether to operate the power amplifier, CFR, and DPD based on the above virtual PAPR value, Even if the above virtual PAPR value changes to exceed or fall below a preset threshold, Characterized by controlling the operation state of the power amplifier, CFR preprocessing function, and DPD preprocessing function to be changed only when the above change state is maintained for a plurality of consecutive OFDM symbols. A communication method that reduces the power consumption of a power amplifier.

9. In Claim 8, In determining whether to operate the power amplifier, CFR, and DPD based on the above virtual PAPR value, A step of obtaining preprocessing execution history information for each OFDM symbol, including at least one of the execution history of the CFR preprocessing function and the execution history of the DPD preprocessing function in previous OFDM symbols; A step of calculating a weight to be applied to the virtual PAPR value based on at least one of the execution frequency of the CFR preprocessing function, the execution frequency of the DPD preprocessing function, or the execution duration included in the preprocessing execution history information; and The method further includes the step of determining whether to operate the power amplifier, CFR preprocessing function, and DPD preprocessing function using a weighted virtual PAPR value reflecting the above-calculated weights. A communication method that reduces the power consumption of a power amplifier.

10. In Claim 1, The step of estimating the signal characteristic value corresponding to the above PAPR is, A power distribution index is additionally calculated to indicate how signal power calculated in the frequency domain is distributed among multiple subcarriers or resource blocks within an OFDM symbol, and The above power distribution indicator includes at least one of a bias, dispersion, or concentration indicator that indicates the degree to which the signal power is concentrated in a specific subcarrier or resource block. Characterized by determining whether to operate the power amplifier, CFR preprocessing function, and DPD preprocessing function by correcting the virtual PAPR value or the signal characteristic value corresponding to the PAPR based on the power distribution index. A communication method that reduces the power consumption of a power amplifier.

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