JP2011066489A - Wireless terminal, transmission power calculation method and computer program in the wireless terminal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wireless terminal capable of calculating total transmission power relatively simply, and to provide a transmission power calculation method and a computer program in the wireless terminal. <P>SOLUTION: The wireless terminal (100) includes: a first calculation section (111) for calculating total transmission power by first operation when a frame structure of a transmission frame modulated by a multi-carrier modulation method is not equal to the frame structure in transmission of previous time; and a second calculation section (111) for calculating the total transmission power by second operation for adding an adjustment amount of the total transmission power based on the control of a wireless base station, to the total transmission power calculated in the previous time, when the frame structure of the transmission frame is equal to the frame structure in transmission of previous time. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a wireless terminal that transmits a wireless signal.

  The present invention is a wireless terminal that moves between communication areas of a plurality of wireless base stations and performs wireless communication with these wireless base stations, and is particularly capable of calculating transmission power, such wireless The present invention can also be applied to a transmission power calculation method in a terminal and a computer program that causes a computer or processor to function as such a wireless terminal.

  In a mobile communication system as an example of a wireless communication system, wireless communication is performed between a wireless base station (BS: Base Station) and a wireless terminal (MS: Mobile Station) connected to an upper network by a wired link. Is called. Thereby, the wireless terminal can transmit and receive various types of information to / from various servers included in the higher-level network or other wireless terminals via the wireless base station. An example of such a wireless communication system is WiMAX (Worldwide Interoperability for Microwave Access), which is being standardized in recent years as IEEE 802.16e. WiMAX uses OFDMA (Orthogonal Frequency Division Multiple Access) as a wireless communication system and uses multiple subcarriers modulated at a high coding rate such as 64QAM (Quadrature Amplitude Modulation) to improve communication speed. I am trying. Furthermore, the wireless communication is simultaneously performed between one wireless base station and each of a plurality of wireless terminals by distinguishing the bands of the same frequency by bursts uniquely specified by the frequency axis and the time axis. .

  In this case, since the radio base station simultaneously receives signals transmitted from a plurality of radio terminals and simultaneously demodulates the signals, it is preferable that reception power of signals transmitted from each of the plurality of radio terminals is substantially uniform. . For this reason, TPC (Transmission Power Control) is performed in such a wireless communication system. In TPC, for example, a protocol for controlling transmission power between a radio base station and a radio terminal (power control protocol) is introduced. On the radio terminal side, transmission power is transmitted according to a control signal corresponding to the protocol from the radio base station. Is controlling.

JP 2004-519182 A JP 2002-354064 A JP 2006-253949 A

  On the other hand, depending on the restrictions on the specifications of a transmission circuit such as an RF amplifier provided in the wireless terminal, there may be a case where transmission with arbitrary transmission power is not possible. For example, a spectrum out of band may be generated due to waveform distortion that can be caused by increasing the output of the transmission circuit. Therefore, the output of the transmission circuit can be increased only to the extent that such waveform distortion does not occur. For this reason, for example, the transmission power for each subcarrier is adjusted according to TPC, and the final transmission power of the entire wireless terminal (hereinafter, referred to as “total transmission power” as appropriate) is also in accordance with the specifications of the wireless terminal. Adjusted according to constraints. In this case, the final transmission power of the entire wireless terminal is calculated on the wireless terminal side. Generally, in a wireless communication system employing a multicarrier modulation scheme such as OFDMA, the calculation of the total transmission power is Processing load tends to be relatively high. Specifically, in a wireless communication system employing a multi-carrier modulation scheme such as OFDMA, each subcarrier is considered while taking into account changes in the frame structure in the time axis direction (for example, changes in the manner of burst allocation). Since the total transmission power is calculated by determining which burst it belongs to, the processing load for calculating the total transmission power becomes relatively high.

However, the calculation of the total transmission power is performed in a short period from when the transmission format instruction is received from the radio base station to when transmission frame transmission is actually started. For this reason, calculating the total transmission power with a relatively high processing load in such a short period leads to an increase in cost and power consumption of the wireless terminal (particularly, a control processor included in the wireless terminal).

An object of the present invention is to provide a wireless terminal capable of relatively easily calculating the total transmission power, a transmission power calculation method in the wireless terminal, and a computer program, for example.

  In the first proposal, a wireless terminal including a first calculation unit and a second calculation unit is used. Each of the first calculation unit and the second calculation unit calculates a total transmission power that is a power necessary for transmitting a transmission frame modulated by the multicarrier modulation scheme.

  Here, a 1st calculation part calculates total transmission power by the 1st calculation which calculates the transmission power requested | required for every subcarrier. In particular, the calculation of the total transmission power by the first calculation unit is performed when the frame structure of the transmission frame (for example, the manner of allocation of bursts included in the transmission frame) is not equivalent to the frame structure at the previous transmission. Here, as the case of “equivalent”, for example, the case where they are the same is not the same, but the total transmission power does not change greatly (the amount of change is within a predetermined range), and the frame structure is changed only to the same extent. One case is an example.

  On the other hand, the second calculation unit calculates an adjustment amount (for example, an adjustment amount based on the power control protocol) of the total transmission power based on the control of the radio base station that is the transmission destination of the transmission frame with respect to the previously calculated total transmission power. The total transmission power is calculated by the second calculation to be added. That is, the second calculation unit can calculate the total transmission power by adding the total transmission power calculated last time and the adjustment amount using the second calculation that is simplified than the first calculation. . In particular, the calculation of the total transmission power by the second calculation unit is performed when the frame structure of the transmission frame is equivalent to the frame structure at the time of previous transmission.

  In the second plan, a wireless terminal including a first calculation step and a second calculation step is used. This transmission power calculation method is a method of calculating the total transmission power, which is the power necessary for transmitting a transmission frame modulated by the multicarrier modulation method. In the first calculation step, the total transmission power is calculated by a first calculation for calculating the transmission power required for each subcarrier. In particular, the calculation of the total transmission power in the first calculation step is performed when the frame structure of the transmission frame is not equivalent to the frame structure at the previous transmission. On the other hand, in the second calculation step, the total transmission power is calculated by a second calculation that adds the adjustment amount of the total transmission power by the control of the radio base station that is the transmission destination of the transmission frame to the previously calculated total transmission power. Is calculated. That is, in the second calculation step, the total transmission power can be calculated by adding the total transmission power calculated last time and the adjustment amount using the second calculation that is simplified than the first calculation. . In particular, the calculation of the total transmission power in the second calculation step is performed when the frame structure of the transmission frame is equivalent to the frame structure at the previous transmission.

  In the third plan, a computer program for operating a wireless terminal that transmits a transmission frame modulated by the multicarrier modulation method is used. This computer program causes the wireless terminal to execute each of the first calculation step and the second calculation step described above. In other words, this computer program causes a wireless terminal (or a control processor or the like provided in the wireless terminal) to function as the first calculation unit and the second calculation unit described above.

  When the frame structure of the transmission frame is the same as the previous frame (the change is not within a predetermined range), it is not always necessary to calculate the total transmission power by performing the first calculation that is a high-precision calculation. . Therefore, the processing load on the wireless terminal can be relatively reduced as compared to a wireless terminal that needs to calculate the total transmission power by performing the first calculation that is always a highly accurate calculation. Therefore, the total transmission power can be calculated relatively easily.

  Further, according to the transmission power calculation method and the computer program described above, it is possible to enjoy the same effects as the above-described wireless terminal.

It is a block diagram which shows notionally the basic composition of the radio | wireless communications system which concerns on 1st Embodiment. It is a block diagram which shows notionally the basic composition of the radio | wireless communications system which concerns on 2nd Embodiment. It is a frame block diagram which shows the structure of the flame | frame in WiMAX. It is a block diagram which shows the basic composition of MS which concerns on 2nd Embodiment. It is a flowchart which shows the flow of the whole operation | movement of the radio | wireless communications system which concerns on 2nd Embodiment. It is a graph which shows a transmission power allowable value notionally. It is a block diagram which shows the basic composition of MS which concerns on 3rd Embodiment. It is a block diagram which shows the basic composition of MS which concerns on 4th Embodiment. It is a flowchart which shows the flow of the whole operation | movement of MS which concerns on 4th Embodiment. It is a block diagram which shows the basic composition of MS which concerns on 5th Embodiment. It is a block diagram which shows the basic composition of MS which concerns on 6th Embodiment.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

(1) 1st Embodiment First, with reference to FIG. 1, a radio | wireless communications system provided with the radio | wireless terminal which concerns on 1st Embodiment is demonstrated as the best form for implementing this invention. FIG. 1 is a block diagram showing a basic configuration of the radio communication system according to the first embodiment.

  As shown in FIG. 1, the wireless communication system 1 according to the first embodiment includes a wireless terminal 10 and a wireless base station 20.

  The radio base station 20 performs radio communication with the radio terminal 10. The radio communication between the radio base station 20 and the radio terminal 10 is realized by transmission / reception of a transmission frame modulated by, for example, a multicarrier modulation scheme using a plurality of subcarriers (for example, OFDMA). The radio base station 20 functions as a relay station for the radio terminal 10 to use a service (in other words, an application) provided from a service station connected to the radio base station 20 via a wired or wireless network. May be.

  The wireless terminal 10 performs wireless communication with the wireless base station 20. In particular, the wireless terminal 10 transmits a transmission frame including some data to the wireless base station 20. The radio terminal 10 preferably receives a transmission frame transmitted from the radio base station 20. Here, in order to calculate the total transmission power required for the radio terminal 10 to transmit a transmission frame including data to the radio base station 20 in particular, the first calculation unit 11, the second calculation unit 12, It has.

  The first calculator 11 calculates the total transmission power using a first calculation that calculates the transmission power required for each subcarrier. That is, the first calculation unit 11 strictly calculates the total transmission power of the entire radio terminal 10 by strictly calculating the transmission power for each subcarrier. As a result, the first calculator 11 can calculate the total transmission power with relatively high accuracy. In particular, the calculation of the total transmission power by the first calculation unit 11 is based on the frame structure of the transmission frame transmitted from the wireless terminal 10 to the wireless base station 20 (for example, the mode of allocation of bursts included in the transmission frame). This is performed when the frame structure of the transmission frame transmitted last time (or transmitted at the timing when the total transmission power was calculated last time) is not equivalent. Here, a specific example in which “the frame structure is equivalent” will be described in detail later. Typically, for example, when the frame structure is the same, the total transmission power does not change greatly, although the frame structure is not the same. There are cases where the frame structure has changed only to the extent that it can be regarded as equivalent, or the dominant burst size and transmission power of the multiple bursts included in the transmission frame are the same and can be regarded as equivalent. As an example.

  On the other hand, the second calculation unit 12 adjusts the total transmission power due to the control of the radio base station 20 that is the transmission destination of the transmission frame with respect to the previously calculated total transmission power (for example, the power control protocol). The total transmission power is calculated using a second calculation that adds the adjustment amount due to the adjustment. In other words, the second calculation unit 12 adds the adjustment amount accompanying the adjustment of the transmission power of the entire plurality of subcarriers performed according to the control or instruction from the radio base station 20 to the previously calculated total transmission power. The total transmission power is calculated using the second calculation. That is, the second calculation unit 12 adds the total transmission power calculated last time and the adjustment amount to the total transmission power by using the second calculation that is relatively simplified compared to the first calculation. Can be calculated. In particular, the calculation of the total transmission power by the second calculation unit 12 is performed when the frame structure of the transmission frame transmitted from the radio terminal 10 to the radio base station 20 is equivalent to the frame structure of the transmission frame transmitted last time. Done.

  According to the wireless communication system 1 according to the first embodiment, the wireless terminal 10 determines that the frame structure of the transmission frame is not equivalent to the frame structure at the previous transmission (in other words, the frame structure of the transmission frame has changed). In some cases, it is sufficient to calculate the total transmission power selectively using a first calculation which is a high-precision calculation for calculating the transmission power for each subcarrier. In other words, when the frame structure of the transmission frame is equivalent to the frame structure at the previous transmission (in other words, when there is no change in the frame structure of the transmission frame), the radio terminal 10 performs high-accuracy calculation. It is not always necessary to calculate the total transmission power using one operation. Therefore, according to the wireless terminal 10 according to the first embodiment, the processing of the wireless terminal 10 is compared with the wireless terminal that needs to calculate the total transmission power by using the first calculation that is always a highly accurate calculation. The load can be relatively reduced. Therefore, the total transmission power can be calculated relatively easily.

  Also, the first calculation unit 11 or the second calculation unit 12 calculates the total transmission power as a value on the logarithmic axis (that is, the decibel value), and the adjustment amount is managed as a value on the logarithmic axis. For example, the second calculation unit 12 can relatively easily calculate the total transmission power by simple addition. In other words, the second calculation unit 12 does not necessarily need to convert the value on the logarithmic axis from the value on the logarithmic axis to the value on the linear axis and add it to the value on the logarithmic axis again for the total transmission power and the adjustment amount. For this reason, the processing load of the radio | wireless terminal 10 can be reduced further.

  If the calculated total transmission power exceeds the allowable range, stable wireless communication can be achieved by controlling the total transmission power of the entire wireless terminal so that the total transmission power is within the allowable range. It can be carried out.

(2) Second Embodiment Next, a second embodiment which is a more specific embodiment of the above wireless communication system will be described.

(2-1) Basic Configuration of Radio Communication System of Second Embodiment First, a basic configuration of a radio communication system 1000 according to the second embodiment will be described with reference to FIG. FIG. 2 is a configuration diagram showing a basic configuration of the wireless communication system 1000 according to the second embodiment.

  As shown in FIG. 2, a wireless communication system 1000 according to the second embodiment includes one or more MSs (Mobile Stations) 100 and one or more BSs (Base Stations) 200. I have.

  In the second embodiment, the following description will be given for the wireless communication system 1000 that is a WiMAX system. However, not only the WiMAX system but also other wireless communication systems (for example, the IMT-2000 system) may adopt the configuration and operation described below in consideration of the specifications of the wireless communication system. .

  The MS 100 establishes a connection with the BS 200 corresponding to the cell 210 in which the MS 100 is located and performs wireless communication. Specifically, the MS 100 receives the frame 400 (see FIG. 3) transmitted from the BS 200. Further, the MS 100 transmits a frame 400 to each of the BSs 200. Examples of such MS 100 include a mobile phone, a PDA (Personal Digital Assistant), and other various information devices having a wireless communication function.

  BS 200 establishes a connection with MS 100 located in cell 210 corresponding to each BS 200 and actually performs wireless communication. Specifically, BS 200 transmits frame 400 to MS 100 located in corresponding cell 210. In addition, the BS 200 receives the frame 400 transmitted from the MS 100 located in the corresponding cell 210.

  Furthermore, in the wireless communication system 1000 according to the second embodiment, wireless communication is performed between the MS 100 and the BS 200 by, for example, transmitting and receiving a frame 400 in a communication system compliant with WiMAX. Therefore, in the wireless communication system 1000 according to the second embodiment, an OFDM (Orthogonal Frequency Division Multiplexing Access) scheme using a plurality of subcarriers or a subchannel consisting of a combination of logical channels and symbols on the frequency axis obtained by dividing the subcarriers. Wireless communication is performed by transmitting and receiving a frame 400 having a predetermined format in the OFDMA (Orthogonal Frequency Division Multiple Access) system to be used.

  Here, the configuration of the frame 400 in WiMAX will be described with reference to FIG. FIG. 3 is a frame configuration diagram conceptually showing the configuration of the frame 400 in WiMAX.

  As shown in FIG. 3A, the frame 400 is configured in units of OFDM frames (or OFDMA frames) specified by subcarriers (that is, frequency) and symbols (that is, time). The frame 400 includes a header portion 410 including control information, a DL (Down Link) subframe portion 420, and a UL (Up Link) subframe portion 430.

  The header portion 410 includes a preamble signal 411, an FCH (Frame Control Header) 412, a DL-MAP (Down Link Mapping message) 413, and an UL-MAP (Up Link Mapping message: Uplink map information) 414.

  The preamble signal 411 is a signal used for the MS 100 to establish synchronization with the BS 200 in the initial stage of communication or to measure the quality of the frame 400 transmitted from the BS 200.

  The FCH 412 is transmitted to inform the terminal of the modulation method and coding method of the DL-MAP 413 and UL-MAP 414 so that the MS 100 can correctly read the control information of the subsequent DL-MAP 413 and UL-MAP 414. Notification information.

  The DL-MAP 413 and the UL-MAP 414 are control information indicating the positions of various data included in the DL subframe portion 420 and the UL subframe portion 430. For example, in the DL subframe portion 420 and the UL subframe portion 430, when various data are included in units of bursts, the DL-MAP 413 and the UL-MAP 414 indicate the burst characteristics (for example, the size of each burst). Control information (for example, DIUC (Downlink Interval Usage Code) or UIUC) indicating the position of each burst, the modulation method of each burst, the encoding method of each burst, the gain specifying the transmission power of each burst, etc. (Burst profile information such as (Uplink Interval Usage Code)).

  DL subframe portion 420 includes data to be transmitted from BS 200 to MS 100. More specifically, the DL subframe portion 420 is divided by one or a plurality of bursts that occupy a square or rectangular region in the DL subframe portion 420. The size of each burst, the position of each burst (in other words, the number of symbols belonging to each burst), the modulation scheme of subcarriers belonging to each burst, the coding scheme of data belonging to each burst, and the transmission power of subcarriers belonging to each burst Is specified by the burst profile information in the DL-MAP 413 described above. Although not shown, the DL subframe portion 420 may be divided into a plurality of zones.

  UL subframe portion 430 includes data to be transmitted from MS 100 to BS 200. More specifically, as shown in FIG. 3B, the UL subframe portion 430 is divided into a plurality of zones (Zone # 1, Zone # 2,...) And the like. Each zone is divided by one or a plurality of bursts that occupy a rectangular area in each zone. FIG. 3B shows an example in which the data is divided by four bursts. The size of each burst, the position of each burst (in other words, the number of symbols belonging to each burst), the modulation scheme of subcarriers belonging to each burst, the coding scheme of data belonging to each burst, and the transmission power of subcarriers belonging to each burst Is specified by the burst profile information in the UL-MAP 414 described above. In the example shown in FIG. 3B, the UL subframe portion 430 is divided into a plurality of zones (Zone # 1, Zone # 2,...), And each Zone is divided by one or a plurality of bursts. An example is described. However, the UL subframe portion 430 may be handled as one area without being divided into a plurality of zones.

  FIG. 3B also shows changes in transmission power in the symbol direction (that is, the time axis direction). Specifically, FIG. 3B shows transmission power for each subcarrier (or for each burst or for each subchannel) at each timing from time T1 to time T6 in the symbol direction. The MS 100 according to the second embodiment adjusts the transmission power for each subcarrier (or for each burst or for each subchannel) based on the above-described UIUC, and according to the transmission power control protocol transmitted from the BS 200. Based on the control message, the final total transmission power of the entire MS 100 (that is, the total transmission power at each time in FIG. 3B) is adjusted. Furthermore, the total transmission power is adjusted as necessary so that the total transmission power does not exceed the maximum transmission power that allows stable wireless communication. Hereinafter, the configuration and operation of the MS 100 that performs such operations will be described in more detail.

(2-2) Basic Configuration of MS (Wireless Terminal) Next, the basic configuration of the MS 100 according to the second embodiment will be described with reference to FIG. FIG. 4 is a block diagram showing the basic configuration of the MS 100 according to the second embodiment.

  As shown in FIG. 4, the MS 100 includes a control circuit 110, a baseband processing circuit 120, and a transmission circuit 130 when attention is focused on its main part.

  The control circuit 110 controls the overall operation of the MS 100. Examples of the control circuit 110 include a CPU (Central Processor Unit) that operates based on predetermined firmware, for example. In order to perform such an operation, the control circuit 110 particularly includes a transmission power determination unit 111 and a gain distribution processing unit as logical or functional processing blocks or physical processing circuits configured therein. 112 and a protocol processing unit 113.

  The transmission power determination unit 111 determines the gain of transmission power for each burst based on the UIUC described above, and outputs the determined gain to the subcarrier gain adjustment unit 123 as an instruction value. The UIUC specifies, for example, a burst modulation scheme and sets a relative gain according to the type of modulation scheme. Therefore, the transmission power determination unit 111 may output the relative gain specified by the UIUC to the gain adjustment unit 123 for each subcarrier. In this case, the gain adjustment section 123 for each subcarrier adjusts the transmission power for each subcarrier by increasing or decreasing the transmission power by a relative gain with respect to a predetermined reference power for each subcarrier.

  The transmission power determination unit 111 indicates processing units that function as a “first calculation unit”, a “second calculation unit”, and a “third calculation unit”, and calculates and calculates the total transmission power of the MS 100 as a whole. The gain of the total transmission power of the MS 100 as a whole is determined based on the total transmission power and the gain specified by the control message according to the power control protocol transmitted from the BS 200. Also, the transmission power determination unit 111 outputs the determined gain of the total transmission power to the gain distribution processing unit 112 as an instruction value.

  The gain distribution processing unit 112 constitutes an example of the “adjustment unit” in the present invention. Based on the gain determined by the transmission power determination unit 111, the gain G_DBB and RF gain adjustment of the baseband gain adjustment unit 126 are performed. Each of the gains G_RF of the unit 131 is determined. Further, the gain distribution processing unit 112 outputs the gain G_DBB to the baseband gain adjustment unit 126 as an instruction value and outputs the gain G_RF to the RF gain adjustment unit 131 as an instruction value.

  The protocol processing unit 113 extracts various control information (for example, UL-MAP 414 and the like) necessary for the MS 100 to generate the frame 400 from the frame 400 transmitted from the BS 200, and performs baseband processing on the control information. Output to the circuit 120. Further, the protocol processing unit 113 outputs transmission data to be transmitted from the MS 100 to the BS 200 to the baseband processing circuit 120. As a result, the baseband processing circuit 120 performs a generation process of the frame 400 including transmission data by performing various modulation processes and encoding processes. In addition, the protocol processing unit 113 analyzes a control message according to the power control protocol transmitted from the BS 200 and outputs the control message to the transmission power determination unit 111. As a result, the transmission power determination unit 111 determines various gains based on a control message corresponding to the power control protocol transmitted from the BS 200.

  The baseband processing circuit 120 generates a baseband signal for transmitting the frame 400 including transmission data, and outputs a transmission signal obtained by converting the baseband signal into an analog signal to the transmission circuit 130. In order to perform such operations, the baseband processing circuit 120 particularly includes a transmission timing generation circuit 121, an OFDMA signal generation unit 122, a gain adjustment unit 123 for each subcarrier, a transmission frame configuration data control unit 124, an IFFT, and the like. (Inverse Fast Fourier Transform) section 125, baseband gain adjustment section 126, and D / A (Digital to Analogue) conversion section 127 are provided.

  The transmission timing generation circuit 121 instructs the OFDMA signal generation unit 122 and the subcarrier gain adjustment unit 123 to synchronize with the transmission timing of the frame 400. As a result, the OFDMA signal generation unit 122 and the subcarrier gain adjustment unit 123 can appropriately generate the frame 400 in synchronization with the transmission timing of the frame 400.

  The OFDMA signal generation unit 122 generates an OFDMA signal. That is, the OFDMA signal generation unit 122 performs transmission data coding (for example, error correction coding such as a convolutional code and a turbo code) processing, and modulation processing such as QPSK modulation and 64QAM modulation, thereby transmitting the transmission data. An including OFDMA signal is generated. In addition, OFDMA signal generation section 122 outputs the generated OFDMA signal to gain adjustment section 123 for each subcarrier.

  Subcarrier gain adjustment section 123 adjusts the transmission power for each subcarrier with the gain specified by transmission power determination section 111. Specifically, since the gain for each burst is specified by the transmission power determining unit 111, the subcarrier gain adjusting unit 123 determines the burst to which each subcarrier belongs, and transmits each subcarrier. Adjust the power.

  Based on the control information output from the protocol processing unit 113, the transmission frame configuration data control unit 124 generates the OFDMA signal having the format of the frame 400 so that the OFDMA signal generation unit 122 and the subcarrier gain adjustment unit 123 Control each action.

  An OFDMA signal generated as a signal on the frequency axis by an IFFT (Inverse Fast Fourier Transform) unit 125 and an OFDMA signal generation unit 122 is converted into a signal on the time axis. That is, IFFT section 125 generates a baseband signal by aggregating various modulation signals generated for each subcarrier (in other words, for each frequency). Further, IFFT unit 125 outputs the baseband signal to baseband gain adjustment unit 126.

  Baseband gain adjustment section 126 adjusts the transmission power of the baseband signal with gain G_DBB specified by transmission power determination section 111. Further, the baseband gain adjustment unit 126 outputs a baseband signal whose transmission power is adjusted to the D / A conversion unit 127.

  A D / A (Digital to Analogue) converter 127 generates a transmission signal by converting a baseband signal into an analog signal. In addition, the D / A converter 127 outputs the generated transmission signal to the transmission circuit 130.

  The transmission circuit 130 actually transmits the transmission signal generated in the baseband processing circuit 120 to the BS 200. In order to perform such an operation, the transmission circuit 130 particularly includes an RF gain adjustment unit 131 and an antenna 132.

  The RF gain adjustment unit 131 converts the transmission signal output from the baseband processing circuit 120 into a signal modulated to a desired transmission frequency, and transmits the transmission signal at a gain G_RF specified by the transmission power determination unit 111. Adjust transmit power. As a result, the transmission signal is radiated from the antenna 132 toward the BS 200 into the space.

  Although FIG. 4 shows the circuit configuration of the transmission system of the MS 100, it is needless to say that the MS 100 may have a circuit configuration of the reception system.

(2-3) Operation of MS (Wireless Terminal) Next, with reference to FIG. 5 and FIG. 6, the flow of operation of the MS 100 in the wireless communication system 1000 according to the second embodiment will be described. FIG. 5 is a flowchart showing the overall flow of the operation of the MS 100 according to the second embodiment, and FIG. 6 is a graph conceptually showing the allowable transmission power value P_limit. Note that FIG. 5 illustrates the operation when adjusting the total transmission power so that the total transmission power of the MS 100 does not exceed the maximum transmission power P_max, which is the maximum transmission power capable of performing stable wireless communication. To do. Therefore, although not shown in FIG. 5, it is preferable that the transmission operation of the frame 400 from the MS 100 to the BS 200 is performed in parallel with the operation illustrated in FIG.

  As shown in FIG. 5, first, the operation of the transmission power determination unit 111 is necessary for the MS 100 to transmit the frame 400 using the simplified calculation that constitutes an example of the “third calculation” in the present invention. Total transmission power P_all ′ is calculated (step S101). At this time, it is preferable that the processing in step S101 is performed after the transmission power is adjusted for each burst by the operation of the gain adjustment unit 123 for each subcarrier based on UIUC. However, the process in step S101 may be performed before the transmission power for each burst is adjusted by the gain adjustment section 123 for each subcarrier.

  Here, as the simplification calculation used in step S101, the transmission power of the subcarrier having the maximum transmission power among the plurality of subcarriers (hereinafter referred to as “maximum subcarrier power” as appropriate) and the transmission of data from the MS 100 Based on the number of subcarriers actually used (that is, the number of subcarriers belonging to a burst actually used for data transmission, hereinafter referred to as “the number of transmission subcarriers”). An example of a calculation method for calculating P_all ′ is given. In this calculation method, the multiplication result of the maximum subcarrier power and the number of transmission subcarriers is preferably handled as the total transmission power P_all '.

  The maximum subcarrier power may be a transmission power of a subcarrier having a maximum transmission power among subcarriers belonging to a burst actually used for data transmission. In this case, the maximum subcarrier power can be calculated relatively easily by referring to the relative gain of the burst specified by the UIUC. That is, the transmission power of the subcarrier after adjusting the transmission power with the maximum relative gain among the relative gains specified by the UIUC is the maximum subcarrier power. Alternatively, the maximum subcarrier power is specified by UIUC or the like regardless of whether or not the subcarrier actually belongs to a burst (that is, whether or not the subcarrier is used for actual data transmission). It may be the maximum transmission power among the transmission powers of all subcarriers. Alternatively, the maximum subcarrier power may be the transmission power of the subcarrier before adjusting the transmission power with the relative gain specified by the UIUC (that is, the reference power for each subcarrier).

  Further, the number of transmission subcarriers is based on the size of the burst belonging to the UL subframe portion 430 (in other words, the number of symbols) and the size of the UL subframe portion 430 (or a zone obtained by further dividing the UL subframe portion 430). Can be calculated. These sizes can be specified by referring to UL-MAP 414. In this case, the number of transmission subcarriers is specified by the size of the burst belonging to frame 400 / the size of UL subframe portion 430 (or a zone obtained by further dividing UL subframe portion 430). However, in consideration of the simplification operation, the fractional part (the part after the decimal point) of the size of the burst belonging to the frame 400 / the size of the UL subframe part 430 (or the Zone obtained by further dividing the UL subframe part 430) ) Is preferably rounded up.

  However, in the UL subframe portion 430, each burst is specified by designating the burst start point and the burst size by the UL-MAP 414. That is, each burst has a shape that wraps around at the boundary of UL subframe portion 430 (or the boundary of Zone). Therefore, by determining which burst belongs to each subcarrier and for each symbol, the number of transmission subcarriers may be calculated strictly correspondingly.

  Here, an example of the simplification calculation will be specifically described using the example of the UL subframe portion 430 illustrated in FIG. Here, it is assumed that the size of Zone # 1 obtained by dividing the UL subframe portion 430 shown in FIG. 3B is 6 symbols. Further, the number of symbols of burst # 1 belonging to Zone # 1 is 20 symbols, the number of symbols of burst # 2 belonging to Zone # 1 is 8 symbols, and the number of symbols of burst # 3 belonging to Zone # 1 is 10 symbols. Suppose that In this case, the number of subcarriers belonging to burst # 1 is 20/6 = 3.33. Similarly, the number of subcarriers belonging to burst # 2 is 8/6 = 1.33... ≈2. Similarly, the number of subcarriers belonging to burst # 3 is 10/6 = 1.66... ≈2. Therefore, the number of transmission subcarriers is 4 + 2 + 2 = 8.

  Note that the aspect of the above-described simplification calculation may be changed depending on whether or not there is a burst that is large enough to be a dominant term in the UL subframe portion 430. Specifically, when there is a burst that is large enough to be the dominant term in the UL subframe portion 430, the transmission power of the subcarrier belonging to the burst that is large enough to be the dominant term is set to the maximum subcarrier power. May be calculated as This is because if there is a burst that is large enough to be the dominant term, the burst contributes greatly to the value of the total transmission power. On the other hand, when there is no burst that is large enough to be a dominant term in the UL subframe portion 430, the transmission power of the subcarrier having the maximum transmission power among the plurality of subcarriers is the maximum subpower as described above. Carrier power. In this case, whether or not there is a burst that is large enough to be a dominant term in the UL subframe portion 430 is determined according to the ratio between the size of the individual burst and the sum of the sizes of all bursts. Are preferred. For example, when the size of an individual burst is a predetermined ratio or more (for example, 50% or more) with respect to the sum of the sizes of all bursts, the burst is large enough to be a dominant term in the UL subframe portion 430. May be determined to exist. For example, in the UL subframe portion 430 shown in FIG. 3B, the number of symbols of burst # 1 belonging to Zone # 1 is 20 symbols, the number of symbols of burst # 2 belonging to Zone # 1 is 8 symbols, and A case where the number of symbols of burst # 3 belonging to Zone # 1 is 10 symbols will be described. In this case, the sum of the sizes of all bursts is 20 + 8 + 10 = 38. Therefore, the ratio between the size of burst # 1 and the sum of the sizes of all bursts is 20/38 = 52.6%> 50%. Therefore, in this case, it is determined that there is a burst # 1 that is large enough to be a dominant term in the UL subframe portion 430. Therefore, the transmission power of subcarriers belonging to burst # 1 is calculated as the maximum subcarrier power.

  In FIG. 5 again, subsequently, the operation of the transmission power determination unit 111 determines whether or not the total transmission power P_all ′ calculated in step S101 is equal to or less than a predetermined transmission power allowable value P_limit (step S102). ). As shown in FIG. 6, the transmission power allowable value P_limit is a value obtained by subtracting an error caused by the simplification calculation from the transmission power maximum value P_max that is the maximum value of transmission power capable of performing stable wireless communication. It may be set.

  As a result of the determination in step S102, when it is determined that the total transmission power P_all ′ is equal to or less than the transmission power allowable value P_limit (step S102: Yes), the actual total transmission power exceeds the transmission power maximum value P_max. Not presumed. Therefore, the operation of the transmission power determination unit 111 and the gain distribution processing unit 112 sets the gain G_DBB so that the output of the baseband processing circuit 120 becomes an appropriate signal level, and the power control protocol transmitted from the BS 200. The gain G_RF is set so that the frame 400 is transmitted with the transmission power specified by the control message in accordance with (step S103).

  In consideration of the circuit characteristics of the RF gain adjusting unit 131, it may be preferable to make the input power level to the RF gain adjusting unit 131 constant. For this reason, in step S103, the gain G_DBB may be set based on the difference between the target input power level to the RF gain adjustment unit 131 and the total transmission power P_all 'calculated by the simplification calculation.

  On the other hand, as a result of the determination in step S102, when it is determined that the total transmission power P_all ′ is not less than or equal to the transmission power allowable value P_limit (step S102: No), the actual total transmission power exceeds the transmission power maximum value P_max. It is estimated that there may be. Therefore, in this case, the total transmission power required for the MS 100 to transmit the frame 400 using the high-precision calculation that constitutes an example of the “first calculation” in the present invention by the operation of the transmission power determination unit 111. P_all is calculated (step S104). As a high-precision calculation, any calculation method may be adopted as long as the calculation accuracy is higher than that of the above-described simplified calculation. However, as an example, it is disclosed in JP-A-2004-519182. The calculation method is given. In this calculation method, transmission for each subcarrier is performed in consideration of changes in the frame structure in the time axis direction (for example, changes in the mode of burst allocation) and determining to which burst each subcarrier belongs. The total transmission power P_all is calculated by sequentially calculating the total power.

  Thereafter, the operation of the transmission power determination unit 111 determines whether or not the total transmission power P_all calculated in step S104 is equal to or less than the transmission power maximum value P_max (step S105).

  As a result of the determination in step S105, when it is determined that the total transmission power P_all is equal to or less than the transmission power maximum value P_max (step S105: Yes), the operations of the transmission power determination unit 111 and the gain distribution processing unit 112 The gain G_DBB is set so that the output of the baseband processing circuit 120 has an appropriate signal level, and the frame 400 is transmitted with the transmission power specified by the control message according to the power control protocol transmitted from the BS 200. The gain G_RF is set so as to be displayed (step S103).

  On the other hand, as a result of the determination in step S105, when it is determined that the total transmission power P_all is not less than or equal to the transmission power maximum value P_max (step S105: No), for example, waveform distortion or the like occurs and stable wireless communication is performed. It is estimated that Therefore, in this case, transmission power saturation correction control is performed by the operation of the transmission power determination unit 111 (step S106). Specifically, the gain of the total transmission power is determined by the operation of the transmission power determination unit 111 so that the total transmission power P_all is reduced by the amount exceeding the maximum transmission power P_max. Thereafter, the gain distribution processing unit 112 sets the gain G_DBB and the gain G_RF according to the gain determined by the transmission power saturation correction control (step S103).

  As described above, the MS 100 according to the second embodiment selectively strictly sets the transmission power for each subcarrier when the total transmission power P_all ′ calculated by the simplification calculation is not less than or equal to the allowable transmission power P_limit. It is sufficient to calculate the total transmission power P_all using the high-precision calculation to be calculated. In other words, when the total transmission power P_all 'calculated by the simplification calculation is equal to or less than the transmission power allowable value P_limit, the MS 100 does not necessarily need to calculate the total transmission power P_all using the high-precision calculation. Therefore, according to the MS 100 according to the second embodiment, it is possible to relatively reduce the processing load of the MS 100 as compared with the MS that always needs to calculate the total transmission power P_all using high-precision arithmetic. Accordingly, the total transmission power can be calculated relatively easily and the transmission power saturation correction control can be performed relatively easily.

  In addition, the total transmission power P_all 'can be calculated relatively easily by using a simplified calculation that calculates the total transmission power P_all' based on the maximum subcarrier power and the number of transmission subcarriers. Furthermore, since it is possible to calculate the total transmission power P_all ′ without converting the relative gain of the burst expressed as a value on the logarithmic axis (decibel value) to a value on the linear axis, the processing load of the MS 100 Can be relatively reduced.

  In addition, by changing the mode of the simplification operation according to whether or not there is a burst that is large enough to be a dominant term in the UL subframe portion 430, the total transmission power P_all is also obtained in the simplification operation. 'Can be calculated with high accuracy.

(3) Third Embodiment Next, an MS 100a according to a third embodiment will be described with reference to FIG. FIG. 7 is a block diagram showing a basic configuration of the MS 100a according to the third embodiment. Note that in the third embodiment, the same components as those of the MS 100 according to the second embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 7, the MS 100 a according to the third embodiment includes a baseband processing circuit 120 and a transmission circuit 130 in the same manner as the MS 100 according to the second embodiment, focusing on its main part. . Further, the MS 100a according to the third embodiment includes a control circuit 110a including a transmission power determination unit 111, a gain distribution processing unit 112, and a protocol processing unit 113.

  Particularly in the MS 100a according to the third embodiment, the control circuit 110a includes a processing load determination unit 114a. The processing load determination unit 114a is configured to be able to appropriately monitor the processing load of the control circuit 110a. When the processing load of the control circuit 110a becomes equal to or higher than the predetermined load (for example, when the CPU usage rate becomes 80% or higher), the processing load determination unit 114a has the processing load equal to or higher than the predetermined load. A control signal indicating this is output to the transmission power determination unit 111.

  When the control signal indicating that the processing load is equal to or greater than the predetermined load is output from the processing load determination unit 114a, the transmission power determination unit 111 does not perform the above-described high-precision calculation. In this case, the transmission power determination unit 111 performs transmission power saturation control when the total transmission power P_all 'calculated by the simplification calculation is equal to or greater than the transmission power maximum value P_max.

  Thereby, while enjoying the effect enjoyed by the MS 100 according to the second embodiment described above, the processing load that is originally assigned to the high-precision calculation is used for other processing (for example, data transmission / reception processing). Can be used for In particular, in a situation where data transmission / reception processing is lost unless the processing load is reduced, data transmission / reception is performed rather than performing transmission power saturation control based on the total transmission power P_all calculated by high-precision calculation. Prioritizing the processing is preferable from the viewpoint of stable wireless communication. For this reason, according to MS100a which concerns on 3rd Embodiment, it does not have a bad influence on the radio | wireless communication which is the original function of MS100a. Nevertheless, since transmission power saturation control can be performed based on the total transmission power P_all ′ calculated by the simplification calculation, there is a disadvantage that the frame 400 is transmitted with an excessive total transmission power equal to or greater than the maximum transmission power value P_max. Can be prevented accordingly.

(4) Fourth Embodiment Next, an MS 100b according to a fourth embodiment will be described with reference to FIGS. FIG. 8 is a block diagram showing a basic configuration of the MS 100b according to the fourth embodiment, and FIG. 9 is a flowchart showing an operation flow of the MS 100b according to the fourth embodiment.

  As shown in FIG. 8, the MS 100 b according to the fourth embodiment includes a baseband processing circuit 120 and a transmission circuit 130 in the same manner as the MS 100 according to the second embodiment, focusing on its main part. . Further, the MS 100b according to the fourth embodiment includes a control circuit 110b including a transmission power determination unit 111, a gain distribution processing unit 112, and a protocol processing unit 113.

  Particularly in the MS 100b according to the fourth embodiment, the control circuit 110b includes a transmission format determination unit 115b. The transmission format determination unit 115b has the same frame structure of the frame 400 for which the current total transmission power P_all is calculated as the frame structure of the transmitted frame 400 for which the previous total transmission power P_all was calculated. It is configured to be able to appropriately determine whether or not there is. Hereinafter, the operation of the MS 100b according to the fourth embodiment including the more detailed operation of the transmission format determination unit 115b will be described with reference to FIG. In FIG. 9, the same steps as those shown in FIG. 5 are denoted by the same step numbers, and detailed description thereof is omitted.

  As shown in FIG. 9, in the MS 100b according to the fourth embodiment, the operations of steps S101 and S102 are performed in the same manner as the MS 100 according to the second embodiment described above.

  As a result of the determination in step S102, when it is determined that the total transmission power P_all ′ is equal to or less than the transmission power allowable value P_limit (step S102: Yes), the operations of the transmission power determination unit 111 and the gain distribution processing unit 112 are performed. The gain G_DBB is set so that the output of the baseband processing circuit 120 has an appropriate signal level, and the transmission of the frame 400 with the transmission power specified by the control message according to the power control protocol transmitted from the BS 200 is performed. The gain G_RF is set to be performed (step S103).

  On the other hand, as a result of the determination in step S102, when it is determined that the total transmission power P_all ′ is not less than or equal to the transmission power allowable value P_limit (step S102: No), subsequently, the operation of the transmission format determination unit 115b causes the current total It is determined whether or not the frame structure of the frame 400 for which the transmission power P_all is calculated is equivalent to the frame structure of the frame 400 for which the previous total transmission power P_all has been calculated (step S201). . That is, whether or not the frame structure of the frame 400 for which the total transmission power P_all is calculated this time has changed compared to the frame structure of the frame 400 for which the total transmission power P_all was previously calculated. Determined.

  Here, the determination of whether or not the frame structure has changed is, for example, (i) the size of the burst included in the UL subframe portion 430 in the frame 400 that is the target of calculation of the total transmission power P_all this time. Is the size of the burst with the largest size among the bursts included in the UL subframe portion 430 in the frame 400 for which the previous total transmission power P_all has been calculated. (Ii) The burst gain having the largest size among the bursts included in the UL subframe portion 430 in the frame 400 that is the target of the calculation of the total transmission power P_all this time is the calculation of the previous total transmission power P_all. The size of the burst included in the UL subframe portion 430 in the frame 400 targeted for Depending on whether or not it is equal to the gain of the burst, and (iii) the size of the burst having the maximum size among the bursts included in the UL subframe portion 430 is greater than or equal to a predetermined size. preferable. Parameters (that is, burst size, gain, etc.) that are the basis for this determination can be identified relatively easily by referring to the UL-MAP 414 described above. For example, (i) the burst size having the largest size among the bursts included in the UL subframe portion 430 in the frame 400 for which the current total transmission power P_all is to be calculated is the calculation of the previous total transmission power P_all. Among the bursts included in the UL subframe portion 430 in the frame 400 that is the target of the frame 400, and is equivalent to the size of the burst having the maximum size. (Ii) The frame that is the target of the calculation of the total transmission power P_all this time Among the bursts included in the UL subframe portion 430 in 400, the gain of the burst having the largest size is the burst gain included in the UL subframe portion 430 in the frame 400 for which the previous total transmission power P_all was calculated. It is equivalent to the gain of the burst with the largest size, and (iii) UL subframe part If the size of the burst size is the maximum of the bursts contained in 430 is equal to or greater than a predetermined size, it is preferably determined frame structure has not changed. On the other hand, for example, (i) the size of the burst having the maximum size among the bursts included in the UL subframe portion 430 in the frame 400 for which the current total transmission power P_all is calculated is the previous total transmission power. Of the bursts included in the UL subframe portion 430 in the frame 400 subject to calculation of P_all, it is not equivalent to the size of the burst having the maximum size. (Ii) This time, the total transmission power P_all is subject to calculation. Among the bursts included in the UL subframe portion 430 in the existing frame 400, the gain of the burst having the maximum size is included in the UL subframe portion 430 in the frame 400 for which the previous total transmission power P_all was calculated. Not equal to the gain of the largest burst among the bursts, or (iii) UL sub- Over if the size of the burst size is the maximum of the bursts contained in the arm portion 430 is less than the predetermined size, it is preferably determined frame structure is changed.

  Of course, other methods may be used to determine whether the frame structure has changed. However, no matter what method is adopted, if it is assumed that the total transmission power due to the burst size (or burst shape, allocation mode, etc.) and the gain itself will change greatly, the frame It is preferable to determine that the structure has changed, and it is assumed that the total transmission power due to the burst size (or burst shape, allocation mode, etc.) and gain itself does not change significantly or is equivalent. It is preferable to determine that the frame structure has not changed.

  As a result of the determination in step S201, the frame structure of the frame 400 that is the target of calculation of the total transmission power P_all this time is changed compared to the frame structure of the frame 400 of which the total transmission power P_all was previously calculated. If it is determined that the transmission power is not determined (step S201: No), the total transmission power P_all is calculated by the difference calculation that constitutes an example of the “second calculation” of the present invention by the operation of the transmission power determination unit 111. (Step S202). Here, the difference calculation is performed by calculating the total transmission power adjustment amount by the control from the BS 200 with respect to the previously calculated total transmission power P_all (in particular, calculating the total transmission power P_all this time after calculating the previous total transmission power P_all). As an example, an operation of adding the adjustment amount until adjustment is performed is given. In other words, an example of the difference calculation is an operation of adding an adjustment amount of the total transmission power that does not depend on the frame 400 itself or the subcarrier itself to the previously calculated total transmission power P_all. Specifically, for example, the difference calculation is performed by adjusting the transmission power of the entire subcarrier according to an instruction such as a control message according to the power control protocol transmitted from the BS 200 with respect to the previously calculated total transmission power P_all. An example of calculating the amount is as follows.

  Of the bursts included in the UL subframe portion 430 in the frame 400 that is the target of calculation of the total transmission power P_all this time, the gain of the burst having the maximum size is relative to the gains of other bursts. If the size is large, it is considered that the burst having the maximum size greatly contributes to the calculation of the total transmission power. Therefore, when the gain of the burst having the maximum size is relatively large compared to the gains of the other bursts, the burst having the maximum size is added to the adjustment amount of the total transmission power by the control from the BS 200. Gain change amount (for example, the gain of the burst having the largest size among the bursts included in the UL subframe portion 430 in the frame 400 for which the current total transmission power P_all is calculated) and the previous total transmission power The transmission power adjustment amount is further added in accordance with the difference between the gain of the burst having the maximum size among the bursts included in the UL subframe portion 430 in the frame 400 subject to calculation of P_all). May be.

  Thereafter, the operation of the transmission power determination unit determines whether or not the total transmission power P_all calculated in step S202 is equal to or less than the transmission power maximum value P_max (step S203).

  As a result of the determination in step S202, when it is determined that the total transmission power P_all is equal to or less than the transmission power maximum value P_max (step S203: Yes), the actual total transmission power does not exceed the transmission power maximum value P_max. Presumed not. Therefore, the operation of the transmission power determination unit 111 and the gain distribution processing unit 112 sets the gain G_DBB so that the output of the baseband processing circuit 120 becomes an appropriate signal level, and the power control protocol transmitted from the BS 200. The gain G_RF is set so that the frame 400 is transmitted with the transmission power specified by the control message in accordance with (step S103).

  On the other hand, as a result of the determination in step S202, when it is determined that the total transmission power P_all is not less than or equal to the maximum transmission power value P_max (step S203: No), the transmission power saturation correction control is performed by the operation of the transmission power determination unit 111. Is performed (step S106). Specifically, the gain of the total transmission power is determined by the operation of the transmission power determination unit 111 so that the total transmission power P_all is reduced by the amount exceeding the maximum transmission power P_max. Thereafter, the gain distribution processing unit 112 sets the gain G_DBB and the gain G_RF according to the gain determined by the transmission power saturation correction control (step S103).

  On the other hand, as a result of the determination in step S201, the frame structure of the frame 400 that is the target of calculation of the total transmission power P_all this time is compared with the frame structure of the frame 400 that is the target of calculation of the previous total transmission power P_all. Is determined to have changed (step S201: Yes), then, by the operation of the transmission power determination unit 111, the total transmission power P_all ′ calculated in step S101 is equal to or less than the transmission power maximum value P_max. It is determined whether or not there is (step S211).

  As a result of the determination in step S211, when it is determined that the total transmission power P_all ′ is equal to or lower than the transmission power maximum value P_max (step S211: Yes), the actual total transmission power exceeds the transmission power maximum value P_max. Not presumed. Therefore, the operation of the transmission power determination unit 111 and the gain distribution processing unit 112 sets the gain G_DBB so that the output of the baseband processing circuit 120 becomes an appropriate signal level, and the power control protocol transmitted from the BS 200. The gain G_RF is set so that the frame 400 is transmitted with the transmission power specified by the control message in accordance with (step S103).

  On the other hand, as a result of the determination in step S211, when it is determined that the total transmission power P_all ′ is not less than or equal to the transmission power maximum value P_max (step S211: No), the actual total transmission power exceeds the transmission power maximum value P_max. It is estimated that there may be. However, as described in the third embodiment, if there is not enough processing capacity of the MS 100c to perform high-precision calculation, it is preferable not to perform high-precision calculation in order to prioritize data transmission / reception processing. Therefore, in this case, it is determined whether or not there is a margin in the processing capacity of the control circuit 110c by the operation of the processing load determination unit 114b (not shown) (step S212). That is, it is determined whether or not the processing load of the processing performed by the control circuit 110c is a predetermined load (for example, 80%) or more (step S212). However, the process may proceed directly to step S104 without performing this determination operation.

  As a result of the determination in step S212, when it is determined that the processing capacity of the control circuit 110c is not sufficient (that is, the processing load of the processing performed by the control circuit 110c is equal to or greater than a predetermined load) (step S212: No) ), Transmission power saturation correction control is performed based on the total transmission power P_all ′ calculated by the simplification calculation in step S101 without performing a high-precision calculation (step S106). That is, the gain of the total transmission power is determined by the operation of the transmission power determination unit 111 so that the total transmission power P_all 'is reduced by the amount exceeding the maximum transmission power value P_max. Thereafter, the gain distribution processing unit 112 sets the gain G_DBB and the gain G_RF according to the gain determined by the transmission power saturation correction control (step S103).

  On the other hand, as a result of the determination in step S212, if it is determined that the processing capacity of the control circuit 110c is sufficient (that is, the processing load of the processing performed by the control circuit 110c is not equal to or greater than a predetermined load) (step S212: Yes) With the operation of the transmission power determination unit 111, the total transmission power P_all is calculated using high-precision calculation (step S104).

  Thereafter, the operation of the transmission power determination unit 111 determines whether or not the total transmission power P_all calculated in step S104 is equal to or less than the transmission power maximum value P_max (step S105).

  As a result of the determination in step S105, when it is determined that the total transmission power P_all is equal to or less than the transmission power maximum value P_max (step S105: Yes), the operations of the transmission power determination unit 111 and the gain distribution processing unit 112 The gain G_DBB is set so that the output of the baseband processing circuit 120 has an appropriate signal level, and the frame 400 is transmitted with the transmission power specified by the control message according to the power control protocol transmitted from the BS 200. The gain G_RF is set so as to be displayed (step S103).

  On the other hand, as a result of the determination in step S105, if it is determined that the total transmission power P_all is not less than or equal to the maximum transmission power value P_max (step S105: No), the transmission power saturation correction control is performed by the operation of the transmission power determination unit 111. Performed (step S106). Specifically, the gain of the total transmission power is determined by the operation of the transmission power determination unit 111 so that the total transmission power P_all is reduced by the amount exceeding the maximum transmission power P_max. Thereafter, the gain distribution processing unit 112 sets the gain G_DBB and the gain G_RF according to the gain determined by the transmission power saturation correction control (step S103).

  As described above, the MS 100c according to the fourth embodiment is more simplified than the high-precision calculation when there is no change in the frame structure while enjoying the effects that the MS 100 according to the second embodiment described above enjoys. The total transmission power P_all can be calculated using the difference calculation. Therefore, when there is no change in the frame structure, it is not necessary to perform high-precision calculations. For this reason, it is possible to relatively reduce the processing load of the MS 100c as compared with the MS that always needs to calculate the total transmission power P_all using high-precision arithmetic.

  In addition, the previous total transmission power P_all calculated as the value on the logarithmic axis (that is, the decibel value) and the adjustment amount of the total transmission power by the control from the BS 200 managed as the value on the logarithmic axis are simply calculated. By adding to, the current total transmission power P_all can be calculated relatively easily. In other words, in order to calculate the total transmission power P_all, it is necessary to convert the total transmission power P_all and the adjustment amount from a value on the logarithmic axis to a value on the linear axis and then add it again to a value on the logarithmic axis. Not necessarily. For this reason, the processing load of MS100b can be reduced relatively.

  In the description of FIG. 9, the simplification calculation is performed, but the simplification calculation is not necessarily performed. For example, without performing steps S101 to S102 of FIG. 9, depending on the determination of whether or not the frame structure has changed, transmission power saturation correction control based on the result of the difference calculation is performed or the result of the high-precision calculation is It may be configured to determine whether to perform transmission power saturation correction control based on. Even with this configuration, as long as the difference calculation simplified than the high-precision calculation is used, the MS 100b is compared with the MS that always needs to calculate the total transmission power P_all using at least the high-precision calculation. The processing load can be relatively reduced.

(5) Fifth Embodiment Next, with reference to FIG. 10, an MS 100c according to a fifth embodiment will be described. FIG. 10 is a block diagram showing a basic configuration of the MS 100c according to the fifth embodiment.

  As shown in FIG. 10, the MS 100 c according to the fifth embodiment includes a baseband processing circuit 120 and a transmission circuit 130 in the same manner as the MS 100 according to the second embodiment, focusing on its main part. . Further, the MS 100c according to the fifth embodiment includes a control circuit 110c including a transmission power determination unit 111, a gain distribution processing unit 112, and a protocol processing unit 113.

  Particularly in the MS 100c according to the fifth embodiment, the control circuit 110c includes a transmission / reception data amount control unit 116c. The transmission / reception data amount control unit 116c takes a value at which the total transmission power P_all ′ (or P_all) calculated by the transmission power determination unit 111 becomes the transmission power maximum value P_max or close to the transmission power maximum value P_max (for example, When the transmission power maximum value P_max is 80% to 95% or 100%, the baseband processing circuit 120 is controlled so as to reduce the amount of data transmitted / received from the MS 100c. In other words, the transmission / reception data amount control unit 116c takes a value at which the total transmission power P_all ′ (or P_all) calculated by the transmission power determination unit 111 becomes the transmission power maximum value P_max or close to the transmission power maximum value P_max. In this case, the baseband processing circuit 120 may reduce the amount of data transmitted / received from the MS 100c as compared with the case where the total transmission power P_all ′ (or P_all) does not take a value close to the transmission power maximum value P_max. To control.

  As a result, the processing load on the control circuit 110c is reduced by the amount of data transmitted / received from / to the MS 100c, so that the transmission power saturation correction control shown in FIGS. Can do. If the amount of data transmitted and received from the MS 100c is not reduced, the processing load on the control circuit 110 may increase. As a result, the control unit 110c may not be able to secure the processing capability for appropriately performing the transmission power saturation correction control illustrated in FIG. 5 and FIG. This may lead to transmission of the frame 400 with a total transmission power higher than the transmission power maximum value P_max. However, according to the fifth embodiment, since it is possible to secure the processing capability for appropriately performing the transmission power saturation correction control shown in FIG. 5 and FIG. 9, the above-described FIG. Stable wireless communication can be performed while appropriately performing the transmission power saturation correction control shown in FIG.

  In the above description, the baseband processing circuit 120 is controlled so that the transmission / reception data amount control unit 116c explicitly reduces the data amount of data transmitted / received from / to the MS 100c. However, the control circuit 110c may operate so that the priority of the calculation of the total transmission power P_all '(or P_all) and the transmission power saturation correction control is higher than the priority of the data transmission / reception process. That is, instead of explicitly reducing the amount of data transmitted / received from / to the MS 100c, when the processing load is high, calculation of the total transmission power P_all ′ (or P_all) and transmission power saturation correction control are preferentially performed. You may comprise so that it may perform. As a result, the processing load assigned to the data transmission / reception processing decreases, and as a result, the amount of transmission / reception data decreases. For this reason, the same effect as the case where the transmission / reception data amount control part 116c reduces the data amount of the data transmitted / received explicitly from MS100c can be enjoyed.

  In addition, the disadvantage that the processing load of the control circuit 110 or the like becomes high is particularly noticeable when the total transmission power P_all is calculated using a high-precision calculation that requires a relatively high processing load. Therefore, the transmission / reception data amount control unit 116c does not need to control the baseband processing circuit 120 so as to reduce the data amount of data transmitted / received from the MS 100c when it is not necessary to perform high-precision arithmetic. For example, as described in the fourth embodiment, when the frame structure has not changed, the total transmission power P_all is calculated by a difference calculation that requires a relatively low processing load compared to the high-precision calculation. In addition, transmission power saturation correction control can be performed. Therefore, the transmission / reception data amount control unit 116c takes a value at which the total transmission power P_all ′ (or P_all) calculated by the transmission power determination unit 111 is the transmission power maximum value P_max or close to the transmission power maximum value P_max. Even in this case, when the frame structure of the frame 400 for which the total transmission power P_all is calculated this time is equivalent to the frame structure of the frame 400 for which the total transmission power P_all was previously calculated The amount of data transmitted and received from the MS 100c need not be reduced. In other words, the transmission / reception data amount control unit 116c has a case where the total transmission power P_all ′ (or P_all) calculated by the transmission power determination unit 111 is close to the transmission power maximum value P_max and the frame structure is changed. In addition, the baseband processing circuit 120 may be controlled so as to reduce the amount of data transmitted / received from the MS 100c.

(6) Sixth Embodiment Subsequently, an MS 100d according to a fifth embodiment will be described with reference to FIG. FIG. 11 is a block diagram showing the basic configuration of the MS 100d according to the sixth embodiment.

  As shown in FIG. 11, the MS 100 d according to the sixth embodiment includes a baseband processing circuit 120 and a transmission circuit 130 in the same manner as the MS 100 according to the second embodiment, focusing on its main part. . Further, the MS 100d according to the sixth embodiment includes a control circuit 110d including a transmission power determining unit 111, a gain distribution processing unit 112, and a protocol processing unit 113.

  Particularly in the MS 100d according to the sixth embodiment, the control circuit 110d includes a transmission / reception data amount measuring unit 117c. The transmission / reception data amount measurement unit 117d is configured to be able to appropriately measure the data amount of data transmitted / received from the MS 100. In particular, the transmission / reception data amount measurement unit 117d is preferably configured to be able to appropriately measure parameters (for example, the number of transmission / reception PDUs) that are greatly related to the processing load of the control circuit 110d.

  When the data amount measured by the transmission / reception data amount measurement unit 117d is the transmission amount limit value of the MS 100 or takes a value close to the transmission amount limit value, the transmission power determination unit 111 and the gain distribution processing unit 112 are described above. The total transmission power is reduced to such an extent that the total transmission power P_all ′ calculated by the simplified calculation does not exceed the maximum transmission power value P_max (or the allowable transmission power value P_limit). This control is preferably performed regardless of whether or not the total transmission power P_all 'is actually equal to or greater than the transmission power maximum value P_max (or the transmission power allowable value P_limit). That is, when the data amount measured by the transmission / reception data amount measurement unit 117d becomes a transmission amount limit value or takes a value close to the transmission amount limit value, the transmission power determination unit 111 and the gain distribution processing unit 112 It is preferable to reduce the total transmission power in advance to such an extent that the transmission power P_all ′ is assumed not to exceed the maximum transmission power value P_max (or the allowable transmission power value P_limit).

  Here, when the data amount of data transmitted / received from the MS 100 becomes a transmission amount limit value or takes a value close to the transmission amount limit value, much of the processing capability of the control circuit 110d is occupied in the data transmission / reception process. It is thought that there is. For this reason, it may become impossible to ensure the processing capability for appropriately performing the transmission power saturation correction control shown in FIGS. This may also lead to transmission of the frame 400 with a total transmission power higher than the transmission power maximum value P_max. However, according to the sixth embodiment, when the data amount becomes the transmission amount limit value or takes a value close to the transmission amount limit value, by reducing the total transmission power in advance, While maintaining the amount of data, the necessity of performing transmission power saturation correction control (particularly, calculation of total transmission power P_all using high-precision arithmetic) is relatively reduced. Therefore, even when the data amount becomes the transmission amount limit value or takes a value close to the transmission amount limit value, the data amount of the transmitted / received data is maintained by reducing the total transmission power in advance. However, the disadvantage that the processing load of the control circuit 110d swells can be suitably prevented.

  In the MS 100 according to the first to sixth embodiments described above, for example, each of the control circuit 110, the baseband processing circuit 120, and the transmission circuit 130 may be provided as a dedicated circuit. Alternatively, at least one of the control circuit 110, the baseband processing circuit 120, and the transmission circuit 130 may be provided as a functional block or a processing block that is realized as a program operation on a general-purpose CPU. In any case, it goes without saying that the various effects described above can be enjoyed.

  The following additional notes are further disclosed with respect to the first to sixth embodiments described above.

(Appendix 1)
When the frame structure of the transmission frame modulated by the multicarrier modulation method is not equivalent to the frame structure at the time of the previous transmission, the transmission frame is transmitted by the first calculation for calculating the transmission power required for each subcarrier. A first calculation unit for calculating the total transmission power required for the transmission, and when the frame structure of the transmission frame is equivalent to the frame structure at the time of previous transmission, A radio terminal comprising: a second calculation unit that calculates the total transmission power by a second calculation that adds an adjustment amount of the total transmission power under control of a radio base station that is a transmission destination of a transmission frame.

(Appendix 2)
The transmission frame includes a plurality of bursts which are information transmission units, and each of the burst size having the maximum size and the gain of the burst having the maximum size among the plurality of bursts at the time of the previous transmission is included. When the size of the burst that is the same as each of the size and the gain and the maximum size is equal to or larger than a predetermined size, the frame structure of the transmission frame is determined to be equivalent to the frame structure at the time of the previous transmission. The wireless terminal according to attachment 1.

(Appendix 3)
In addition to the total transmission power adjustment amount by the control of the radio base station, the second calculation unit sets the gain change amount of the burst having the maximum size to the previously calculated total transmission power. The wireless terminal according to supplementary note 2, wherein the total transmission power is calculated by adding a corresponding transmission power adjustment amount.

(Appendix 4)
The apparatus further includes a third calculation unit that calculates the total transmission power by a third calculation that is simplified than the first calculation, and the first calculation unit calculates the total transmission calculated by the third calculation unit. When the power is greater than or equal to a predetermined threshold, the total transmission power is calculated by the first calculation, and the second calculation unit calculates whether the total transmission power calculated by the third calculation unit is the predetermined threshold. The wireless terminal according to any one of supplementary notes 1 to 3, wherein the total transmission power is calculated by the second calculation in the case of the above.

(Appendix 5)
The third calculation is a calculation based on each of the transmission power of the subcarrier having the maximum transmission power among the plurality of subcarriers and the number of subcarriers used for transmitting information from the wireless terminal. The wireless terminal described in 1.

(Appendix 6)
The transmission frame includes a plurality of bursts which are information transmission units, and the third calculation is performed when (i) the size of the burst having the maximum size among the plurality of bursts is equal to or larger than a predetermined size. Is a calculation based on transmission power of a subcarrier used for transmission of a burst having the maximum size, and (ii) the size of the burst having the maximum size among the plurality of bursts is less than the predetermined size. In some cases, the wireless terminal according to supplementary note 5, which is a calculation based on transmission power of a subcarrier having maximum transmission power among a plurality of subcarriers.

(Appendix 7)
The wireless terminal further includes an adjustment unit that adjusts the total transmission power according to the total transmission power calculated by at least one of the first calculation unit, the second calculation unit, and the third calculation unit. When the processing load is equal to or greater than a predetermined load, the first calculation unit is configured to perform the first calculation even when the total transmission power calculated by the third calculation unit is equal to or greater than the predetermined threshold. The adjustment unit does not calculate the total transmission power by calculation, and the adjustment unit adjusts the total transmission power according to the total transmission power calculated by at least one of the second calculation unit and the third calculation unit. The wireless terminal according to any one of appendices 4 to 6.

(Appendix 8)
In any one of appendices 1 to 7, further comprising a reduction unit that reduces the transmission rate of the transmission frame when the total transmission power is a value equal to or greater than a predetermined ratio with respect to a transmission power limit value of the wireless terminal. The wireless terminal described.

(Appendix 9)
The transmission rate of the transmission frame is equal to or greater than a predetermined first ratio with respect to the transmission capability limit value of the wireless terminal, and the total transmission power is equal to or greater than a predetermined second ratio with respect to the transmission power limit value of the wireless terminal. The wireless terminal according to any one of appendices 1 to 7, further comprising a reduction unit that reduces the total transmission power.

(Appendix 10)
A first calculation unit that calculates a total transmission power required for transmitting a transmission frame modulated by the multicarrier modulation method by a first calculation; and a transmission power calculated by the first calculation unit is equal to or greater than a predetermined threshold value And a second calculation unit that calculates the total transmission power by a second calculation with higher accuracy than the first calculation.

(Appendix 11)
The first calculation is an operation based on the transmission power of the subcarrier having the maximum transmission power among the plurality of subcarriers and the number of subcarriers used for transmission of information from the wireless terminal. The wireless terminal according to Supplementary Note 10, which is characterized.

(Appendix 12)
The transmission frame includes a plurality of bursts which are information transmission units, and the third calculation is performed when (i) the size of the burst having the maximum size among the plurality of bursts is equal to or larger than a predetermined size. Is a calculation based on transmission power of a subcarrier used for transmission of a burst having the maximum size, and (ii) the size of the burst having the maximum size among the plurality of bursts is less than the predetermined size. In some cases, the wireless terminal according to supplementary note 11, which is a calculation based on transmission power of a subcarrier having maximum transmission power among a plurality of subcarriers.

(Appendix 13)
An adjustment unit for adjusting the total transmission power according to the total transmission power calculated by at least one of the first calculation unit and the second calculation unit;
When the processing load of the wireless terminal is equal to or greater than a predetermined load, the second calculation unit may be a case where the total transmission power calculated by the first calculation unit is equal to or greater than the predetermined threshold. Any one of Supplementary notes 10 to 12, wherein the total transmission power is not calculated by the second calculation, and the adjustment unit adjusts the total transmission power according to the total transmission power calculated by the first calculation unit. A wireless terminal according to claim 1.

(Appendix 14)
Additional remark 10 WHEREIN: When the said total transmission power turns into a value more than predetermined ratio with respect to the transmission power limit value of the said radio | wireless terminal, The reduction part which lowers | hangs the transmission rate of the said transmission frame is added to any one of the appendix 10-13 The wireless terminal described.

(Appendix 15)
Any one of Supplementary notes 10 to 14, further comprising a reduction unit that reduces the total transmission power when the transmission rate of the transmission frame is a value equal to or greater than a predetermined ratio with respect to a transmission capability limit value of the wireless terminal. The wireless terminal described.

(Appendix 16)
A first calculation unit that calculates a total transmission power necessary for transmitting a transmission frame modulated by the multicarrier modulation scheme by a first calculation, and the total transmission power calculated by the first calculation unit is a predetermined value. A wireless terminal comprising: a reduction unit that reduces the transmission rate of the transmission frame when the threshold is equal to or greater than a threshold.

(Appendix 17)
A first calculation unit for calculating a total transmission power required for transmitting a transmission frame modulated by the multicarrier modulation method by a first calculation; and a transmission rate of the transmission frame is set to a transmission capability limit value of the wireless terminal. When the total transmission power calculated by the first calculation unit is equal to or greater than a predetermined second ratio with respect to the transmission power limit value of the wireless terminal, A wireless terminal comprising: a reduction unit that reduces transmission power.

(Appendix 18)
When the frame structure of the transmission frame modulated by the multicarrier modulation method is equivalent to the frame structure at the time of previous transmission, the transmission frame is transmitted by the first calculation for calculating the transmission power required for each subcarrier. A first calculation step of calculating a total transmission power required to perform the above, and when the frame structure of the transmission frame is not equal to the frame structure at the time of previous transmission, A transmission power calculation method in a wireless terminal, comprising: a second calculation step of calculating the total transmission power by a second calculation of adding an adjustment amount of the total transmission power under the control of a base station that is a transmission destination of a transmission frame.

(Appendix 19)
A computer program for operating a wireless terminal that transmits a transmission frame modulated by a multicarrier modulation scheme, wherein the frame structure of a transmission frame modulated by a multicarrier modulation scheme is a frame structure at the time of previous transmission. If they are equivalent, a first calculation step of calculating a total transmission power required for transmitting the transmission frame by a first calculation for calculating a transmission power required for each subcarrier; When the frame structure is not equivalent to the frame structure at the time of previous transmission, the adjustment amount of the total transmission power by the control of the base station that is the transmission destination of the transmission frame is added to the total transmission power calculated last time A computer program that executes a second calculation step of calculating the total transmission power by a second calculation.

  The present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the spirit or idea of the invention that can be read from the claims and the entire specification, and a radio terminal accompanying such a change A transmission power calculation method and a computer program in a wireless terminal are also included in the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 1,1000 Wireless communication system 10 Wireless terminal 11 1st calculation part 12 2nd calculation part 20 Wireless base station 100 MS
110 control circuit 111 transmission power determination unit 112 gain distribution processing unit 113 protocol processing unit 120 baseband processing circuit 121 transmission timing generation unit 122 OFDMA signal generation unit 123 gain adjustment unit for each subcarrier 124 transmission frame configuration data control unit 125 IFFT unit 126 Baseband gain adjustment unit 127 D / A conversion unit 130 Transmission circuit 131 RF gain adjustment unit 132 Antenna 200 BS
400 Frame 413 DL-MAP
414 UL-MAP
420 DL subframe portion 430 UL subframe portion

Claims (11)

When the frame structure of the transmission frame modulated by the multicarrier modulation method is not equivalent to the frame structure at the time of the previous transmission, the transmission frame is transmitted by the first calculation for calculating the transmission power required for each subcarrier. A first calculation unit for calculating the total transmission power required for
When the frame structure of the transmission frame is equivalent to the frame structure at the time of previous transmission, the total transmission by the control of the radio base station that is the transmission destination of the transmission frame with respect to the total transmission power calculated last time A wireless terminal comprising: a second calculation unit that calculates the total transmission power by a second calculation that adds a power adjustment amount. The transmission frame includes a plurality of bursts which are information transmission units,
The burst having the maximum size among the plurality of bursts and the gain of the burst having the maximum size are substantially the same as the size and gain at the previous transmission, and the burst having the maximum size. 2. The wireless terminal according to claim 1, wherein a frame structure of the transmission frame is determined to be equivalent to a frame structure at the previous transmission when the size of the transmission frame is equal to or larger than a predetermined size.   In addition to the total transmission power adjustment amount by the control of the radio base station, the second calculation unit sets the gain change amount of the burst having the maximum size to the previously calculated total transmission power. The wireless terminal according to claim 2, wherein the total transmission power is calculated by adding an adjustment amount of the corresponding transmission power. A third calculation unit that calculates the total transmission power by a third calculation simplified than the first calculation;
The first calculation unit calculates the total transmission power by the first calculation when the total transmission power calculated by the third calculation unit is equal to or greater than a predetermined threshold;
The second calculation unit calculates the total transmission power by the second calculation when the total transmission power calculated by the third calculation unit is equal to or greater than the predetermined threshold. Item 4. The wireless terminal according to any one of Items 1 to 3.   The third operation is an operation based on the transmission power of the subcarrier having the maximum transmission power among the plurality of subcarriers and the number of subcarriers used for transmitting information from the wireless terminal. The wireless terminal according to claim 4, characterized in that: The transmission frame includes a plurality of bursts which are information transmission units,
The third calculation is as follows: (i) When the size of the burst having the maximum size among the plurality of bursts is equal to or larger than a predetermined size, the subcarrier used for transmission of the burst having the maximum size is determined. (Ii) a subcarrier having the maximum transmission power among the plurality of subcarriers when the size of the burst having the maximum size among the plurality of bursts is less than the predetermined size. The wireless terminal according to claim 5, wherein the calculation is based on the transmission power of the wireless terminal. An adjustment unit for adjusting the total transmission power according to the total transmission power calculated by at least one of the first calculation unit, the second calculation unit, and the third calculation unit;
When the processing load of the wireless terminal is equal to or greater than a predetermined load, the first calculation unit may be a case where the total transmission power calculated by the third calculation unit is equal to or greater than the predetermined threshold. The total transmission power is not calculated by the first calculation, and the adjustment unit performs the total transmission according to the total transmission power calculated by at least one of the second calculation unit and the third calculation unit. The radio terminal according to any one of claims 4 to 6, wherein power is adjusted.   8. The apparatus further comprises a reduction unit that reduces the transmission rate of the transmission frame when the total transmission power becomes a value equal to or greater than a predetermined ratio with respect to a transmission power limit value of the wireless terminal. The wireless terminal according to any one of the above.   The transmission rate of the transmission frame is equal to or greater than a predetermined first ratio with respect to the transmission capability limit value of the wireless terminal, and the total transmission power is equal to or greater than a predetermined second ratio with respect to the transmission power limit value of the wireless terminal. The wireless terminal according to any one of claims 1 to 7, further comprising a reduction unit that reduces the total transmission power. When the frame structure of the transmission frame modulated by the multicarrier modulation method is equivalent to the frame structure at the time of previous transmission, the transmission frame is transmitted by the first calculation for calculating the transmission power required for each subcarrier. A first calculation step of calculating a total transmission power necessary for performing,
When the frame structure of the transmission frame is not equivalent to the frame structure at the time of previous transmission, the total transmission power calculated by the control of the base station that is the transmission destination of the transmission frame is compared with the total transmission power calculated last time. And a second calculation step of calculating the total transmission power by a second calculation for adding the adjustment amount. A transmission power calculation method in a wireless terminal. A computer program for operating a wireless terminal that transmits a transmission frame modulated by a multicarrier modulation method,
When the frame structure of the transmission frame modulated by the multi-carrier modulation scheme in the wireless terminal is equivalent to the frame structure at the time of the previous transmission, the first calculation for calculating the transmission power required for each subcarrier A first calculation step of calculating a total transmission power necessary for transmitting the transmission frame;
When the frame structure of the transmission frame is not equivalent to the frame structure at the time of previous transmission, the total transmission power calculated by the control of the base station that is the transmission destination of the transmission frame is compared with the total transmission power calculated last time. And a second calculation step of calculating the total transmission power by a second calculation for adding the adjustment amount.

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