WO2011040598A1

WO2011040598A1 - Transmitter apparatus, receiver apparatus, communication system and transmission method

Info

Publication number: WO2011040598A1
Application number: PCT/JP2010/067251
Authority: WO
Inventors: 理中村; 泰弘浜口; 昇平山田; 一成横枕; 淳悟後藤; 宏樹高橋
Original assignee: シャープ株式会社
Priority date: 2009-10-01
Filing date: 2010-10-01
Publication date: 2011-04-07
Also published as: JP2011077996A

Abstract

Even when a terminal, which is to perform CA, transmits a transport signal having a plurality of CCs by use of PAs the number of which is smaller than that of those CCs, a high-efficiency communication can be achieved with the compatibility with LTE being maintained. A transmitter apparatus, which uses a plurality of carrier components to transmit information, comprises: a combining unit (115) including amplifiers the number of which is smaller than that of carrier components; required transmission power calculating units (105-1 to 105-5) each for calculating a desired transmission power for a respective one of the carrier components; a maximum permissible transmission power setting unit (109) for setting the maximum permissible transmission power; and PH calculating units (107-1 to 107-5) each for calculating a PH (Power Headroom) between the maximum permissible transmission power and the respective required transmission power.

Description

Transmission device, reception device, communication system, and transmission method

The present invention relates to a wireless communication system that performs transmission power control efficiently while performing wireless communication using one or more carrier components.

The LTE (Long Term Evolution) system, which is a wireless communication system for 3.9th generation mobile phones, can communicate using a maximum bandwidth of 20 MHz.

As the transmission method, OFDM (Orthogonal Frequency Division Multiplexing) is adopted. OFDM is a communication system with a high PAPR (Peak-to-Average Power Ratio), and a transmitter requires a class A power amplifier (Power Amplifier, PA), but the base station transmits it. Since it is not necessary to consider the scale of the machine so much, the adoption is decided in the downlink of LTE. On the other hand, in LTE uplink (communication from a terminal to a base station), since the cost and scale of the terminal are important, the PAPR is low, and a multi-user diversity effect by frequency scheduling can be obtained. SC-FDMA (Single-Carrier-Frequency-Division) Multiple Access) is adopted.

Also, in the uplink, transmission power control (Transmit Power Control, TPC) is performed for the purpose of suppressing power consumption of the terminal and reducing interference with other cells. The formula used in order to determine the transmission power value used for the uplink data communication prescribed | regulated to a nonpatent literature 1 is shown.

In Equation (1), PUSCH is an abbreviation for Physical Uplink Shared Channel, and indicates a physical channel that transmits uplink data. P _push (i) indicates a transmission power value in the i-th frame. min {X, Y} is a function for selecting the minimum value of X and Y. P _{o_push} (j) is a transmission power that is the basis of PUSCH, and j is a variable that represents a transmission mode, and is a value specified by an upper layer. M _push (i) indicates the number of resource blocks (RB: a unit by which a terminal accesses the base station) used for data channel transmission, and indicates that the transmission power increases as the number of RBs used increases. ing. Further, PL indicates a path loss, and α (j) is a coefficient by which the path loss is multiplied, and is specified by an upper layer. Δ _TF (i) is an offset value based on a modulation scheme or the like, and f (i) is an offset value (transmission power control value based on a closed loop) calculated by a control signal from the base station. Further, _PCMAX is an allowable maximum transmission power value, which may be a physical maximum transmission power or may be specified from an upper layer.

In addition, in order for the base station to recognize how much margin the terminal is transmitting with respect to the allowable maximum transmission power P _CMAX , the terminal is called a power headroom (PH). The terminal notifies the base station of a value obtained by subtracting the required transmission power from the maximum allowable transmission power. PH is defined by the formula (2) in Non-Patent Document 1.

The PH is rounded to a value of −23 dB to 40 dB in 1 dB increments, notified from the physical layer to the upper layer, and transmitted to the base station. A positive PH indicates that there is a margin in the terminal PA (Power Amplifier), and a negative PH indicates that the terminal is requesting transmission power exceeding the maximum allowable transmission power from the base station. Indicates a state in which transmission is performed with an allowable maximum transmission power. The base station determines the bandwidth used by the terminal, the modulation method, and the like based on the PH.

In recent years, standardization of the LTE-Advanced (LTE-A) system, which has been developed from the LTE system, has started. In LTE-A, in addition to SC-FDMA, the adoption of Clustered DFT-S-OFDM (Discrete-Fourier-Transform-Spread-Orthogonal-Frequency-Division-Multiplexing) that allows discrete arrangement of RBs is also decided. In addition, LTE-A can perform communication using a maximum frequency band of 100 MHz while maintaining backward compatibility with LTE. Therefore, in LTE-A, up to five 20 MHz LTE systems are arranged on the frequency axis to support a frequency band of up to 100 MHz. Each 20 MHz band is referred to as a carrier component (CC), and an LTE-A terminal using a frequency band of 20 MHz or more performs communication using a plurality (up to 5) CCs, and an LTE terminal includes a plurality of Communication is performed using one of the CCs. Furthermore, it is conceivable that transmission power control is performed independently for each CC. Note that communication using a plurality of CCs is referred to as carrier aggregation (Carrier-Aggregation, CA). When performing CA, if there is a PA for each CC, TPC may be performed for each CC, and PH may be notified to the base station for each CC.

However, when considering transmission signals of a plurality of CCs with one PA, if the terminal performs TPC for each CC and notifies PH to the base station, the PH value differs for each CC. This becomes a problem when the base station determines the bandwidth to be used, the modulation method, and the like. For example, when transmitting three or more CCs by two PAs, the base station needs to be able to recognize which CC is transmitted using the same PA.

The present invention has been made in view of such circumstances, and maintains compatibility with LTE even when a terminal that performs CA transmits a plurality of CC transmission signals with a PA that is smaller than the number of CCs. An object of the present invention is to provide a transmission device, a reception device, a communication system, and a transmission method capable of performing highly efficient communication.

(1) In order to achieve the above object, the present invention has taken the following measures. That is, the transmission apparatus of the present invention is a transmission apparatus that transmits information using a plurality of carrier components, and calculates a smaller number of amplifiers than the number of carrier components and desired transmission power in each of the carrier components. A required transmission power calculation unit, an allowable maximum transmission power setting unit that sets an allowable maximum transmission power, and a PH calculation unit that calculates a PH (Power Headroom) between the allowable maximum transmission power and the required transmission power. It is characterized by.

In this way, the transmission device calculates the desired transmission power in each carrier component, sets the allowable maximum transmission power, and calculates the PH (PowerroomHeadroom) between the allowable maximum transmission power and the required transmission power. A mismatch between actual transmission power and PH does not occur, and when the transmission apparatus performs transmission, power exceeding the performance of the PA is input, and distortion does not occur in the transmission signal. Further, it is possible to perform transmission in consideration of actual transmission power while maintaining compatibility with LTE.

(2) Further, in the transmission device of the present invention, the allowable maximum transmission power setting unit uniformly sets the allowable maximum transmission power in each carrier component according to the number of carrier components to be used.

In this way, since the transmission apparatus uniformly sets the maximum allowable transmission power in each carrier component according to the number of carrier components to be used, the total transmission power required for all carrier components can be calculated with a relatively simple calculation method. The carrier component allowable maximum transmission power can be set so as to be always below the allowable maximum transmission power.

(3) In the transmission apparatus of the present invention, the allowable maximum transmission power setting unit sets the allowable maximum transmission power for each carrier component according to QoS (QualityQualOf Service) of each carrier component. Features.

Thus, since the allowable maximum transmission power is set for each carrier component according to the QoS (Quality Of Service) of each carrier component, the desired communication quality can be satisfied even when the QoS of data handled by the carrier component differs.

(4) In the transmission apparatus of the present invention, the PH calculation unit further includes a required transmission power total unit that outputs the required transmission power total value by summing the required transmission power values output by the required transmission power calculation unit. Calculates the PH of the allowable maximum transmission power and the total required transmission power.

In this way, since the transmission apparatus calculates the PH of the allowable maximum transmission power and the total required transmission power, even if the required transmission power is biased in each CC while maintaining compatibility with LTE, PA It is possible to perform communication using the performance of.

(5) The transmission apparatus of the present invention is further characterized by further comprising an amplifier information adding unit for adding amplifier information for identifying the amplifier to information output from the PH calculating unit.

As described above, the transmitter apparatus adds amplifier information for identifying the amplifier to the PH information, so that the receiver apparatus can identify which CC is transmitted by the same PA while maintaining compatibility with LTE. become. As a result, the TPC command notified from the receiving apparatus to the transmitting apparatus can be determined in consideration of the use of the same PA, so that efficient TPC is possible.

(6) In the transmission device of the present invention, the PH calculation unit outputs 6-bit information indicating PH, and the amplifier information addition unit adds the 6-bit information output from the PH calculation unit to the 6-bit information. Two-bit information for identifying an amplifier is added.

As described above, since the transmission apparatus adds 2-bit information for identifying the amplifier to the 6-bit information about PH, PH can be maintained at 1 byte (8 bits). As a result, PA information can be added without increasing control information while maintaining compatibility with LTE.

(7) Further, the transmitting apparatus of the present invention is further characterized by further comprising a used amplifier determining unit that determines an amplifier to be used according to a propagation path state.

Thus, since the transmission apparatus determines the amplifier to be used according to the propagation path state, it can adaptively cope with the case where the propagation state fluctuates over time.

(8) Further, the receiving device of the present invention receives the amplifier information from the transmitting device according to any one of (5) to (7), and the carrier components are transmitted based on the amplifier information. An amplifier is identified.

In this way, since the receiving apparatus identifies the amplifier to which each carrier component is transmitted based on the amplifier information, the receiving apparatus can determine which CC is transmitted by the same PA while maintaining compatibility with LTE. Can be identified. As a result, the receiving apparatus can determine the TPC command to be notified to the transmitting apparatus in consideration of the use of the same PA, thereby enabling efficient TPC.

(9) The communication system of the present invention is a communication system including a transmission device that transmits information using a plurality of carrier components and a reception device that receives information transmitted from the transmission device, The transmission device includes a smaller number of amplifiers than the number of carrier components, a required transmission power calculation unit that calculates desired transmission power in each carrier component, an allowable maximum transmission power setting unit that sets an allowable maximum transmission power, A PH calculation unit for calculating a PH (Power Headroom) between the allowable maximum transmission power and the required transmission power; an amplifier information addition unit for adding amplifier information for identifying the amplifier to information output from the PH calculation unit; The receiving device receives the amplifier information from the transmitting device, and based on the amplifier information, Turbocharger rear component is characterized to identify the transmitted amplifier.

As described above, since the transmitter apparatus adds amplifier information for identifying the amplifier to the information on PH, the receiver apparatus can identify which CC is transmitted by the same PA while maintaining compatibility with LTE. become. As a result, the TPC command notified from the receiving apparatus to the transmitting apparatus can be determined in consideration of the use of the same PA, so that efficient TPC is possible.

(10) Further, the transmission method of the present invention is a transmission method of a transmission apparatus that has a smaller number of amplifiers than the number of carrier components and transmits information using a plurality of carrier components, and is a desired method in each of the carrier components. Respectively, a step of uniformly setting an allowable maximum transmission power in each of the carrier components in accordance with the number of carrier components to be used, and a PH of the allowable maximum transmission power and the required transmission power ( And calculating at least (Power Headroom).

In this way, the transmission apparatus uniformly sets the maximum allowable transmission power in each carrier component according to the number of carrier components to be used, and calculates the PH (PowerroomHeadroom) between the maximum allowable transmission power and the required transmission power. The carrier component allowable maximum transmission power can be set by a relatively simple calculation method so that the total transmission power required for all carrier components is always lower than the allowable maximum transmission power.

According to the present invention, even when an LTE-A terminal that performs CA has a smaller number of PAs than the number of CCs to be used, it is possible to perform highly efficient communication while maintaining compatibility with LTE.

It is a block diagram which shows the mobile terminal structure which concerns on the 1st Embodiment of this invention. It is the figure which showed the relationship between the transmission power in each CC, and permissible maximum transmission power _PCMAX . In the 1st Embodiment of this invention, it is the figure which showed the relationship between the transmission power in each CC, and the corrected permissible maximum transmission power _PCMAX . It is a flowchart which shows the PH calculation method of the transmitter which concerns on the 1st Embodiment of this invention. It is a block diagram which shows the mobile terminal structure which concerns on the 2nd Embodiment of this invention. It is a block diagram which shows the mobile terminal structure which concerns on the 3rd Embodiment of this invention. It is a block diagram which shows the mobile terminal structure which concerns on the 4th Embodiment of this invention. It is a figure which shows which CC each CC is transmitted at the time t regarding the 4th Embodiment of this invention (when the number of CCs is 3 and the number of PAs is 2). FIG. 10 is a diagram showing which PA is used to transmit each CC at time t + T with respect to the fourth embodiment of the present invention (the required transmission power of CC # 3 increases and the most required transmission among three CCs) If power is high).

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[First Embodiment]
As a first embodiment, a single power amplifier (PA: Power Amplifier) amplifies and transmits signals of a plurality of CCs (abbreviation of Carrier Component, which will be described as five CCs in this embodiment) The PH notification method will be described.

FIG. 1 is a block diagram showing a mobile terminal configuration according to the first embodiment of the present invention. Normally, control information such as a modulation scheme, coding rate, used RB information, and TPC command used for uplink communication is transmitted from a base station to a terminal using a PDCCH that is a downlink physical channel. The receiving antenna unit 101 inputs the received PDCCH to the CC # 1 PDCCH receiving unit 103-1 to CC # 5 PDCCH receiving unit 103-5. Each PDCCH receiving unit 103 inputs control information necessary for calculating the required transmission power to the required transmission power calculating unit 105 corresponding to each PDCCH receiving unit 103. In each required transmission power calculation section 105, the modulation scheme, the used bandwidth, the transmission scheme (SC-FDMA or Clustered DFT-S-OFDM), the TPC command, and the terminal, which are transmitted by PDCCH, are estimated from the downlink received power. A transmission power P _req for satisfying a predetermined communication quality in the base station is calculated based on the equation (1) by the path loss PL, the coefficient α multiplied by the path loss notified from the higher layer, and the like. _Preq output from each required transmission power calculation unit 105 is input to each PH calculation unit 107.

Here, the processing of each PH calculation unit 107 will be described. In LTE, PH is calculated by equation (2). In the present embodiment, the allowable maximum transmission power P _CMAX is _notified from the CC allowable maximum transmission power setting unit (allowable maximum transmission power setting unit) 109. Here, if transmission is _performed with the maximum allowable transmission power P _CMAX in each CC, there is a problem that the total allowable maximum transmission power is exceeded.

FIG. 2A is a diagram showing a relationship between transmission power and allowable maximum transmission power _PCMAX in each CC. For example, as shown in FIG. 2A, when the allowable maximum transmission power P _CMAX when only one CC such as LTE is used is applied to a case where a plurality of CCs are used as they are, the transmission power becomes P _{CMAX in} each CC. Thus, TPC may be performed. As a result, power exceeding the linear region of the PA is input to the PA, and the transmission signal is distorted, and interference with other cells is increased.

Therefore, in the present embodiment, the used CC number notifying unit 111 in FIG. 1 notifies the CC allowable maximum transmission power setting unit 109 of the number of CCs supported by the PA, and the CC allowable maximum transmission power setting unit 109 calculates the expression (3). Based on this, the allowable maximum transmission power PCC for each _CC is determined.

Here, _PCMAX is an allowable maximum transmission power value of all CCs in each terminal, and may be a physical maximum transmission power or may be designated from an upper layer. X is a value determined by the number of used CCs notified from the used CC number notifying unit 111, and for example, the numerical values described in Table 1 are used.

FIG. 2B is a diagram illustrating a relationship between the transmission power in each CC and the corrected allowable maximum transmission power P _CMAX in the first embodiment of the present invention. FIG. 2B shows an example in which three CCs are transmitted by one PA. Since three CCs are used, X = 4.77 is used from Table 1. As a result, CC allowable maximum transmission power setting section 109 _notifies each PH calculation section 107 of the allowable maximum transmission power with P _CMAX -X as the allowable maximum transmission power. Since the transmission power of each CC _{does not} exceed P _CMAX -4.77 (= P _CMAX / 3), the total transmission power of the _{three CCs} is necessarily lower than P _CMAX . As a result, the signal can be transmitted without distorting the output signal of the PA.

The PH calculation unit 107 calculates PH (i) of the i-th frame based on the equation (4) using the allowable maximum transmission power P _cc and the required transmission power P _req for each CC input.

FIG. 3 is a flowchart showing a PH calculation method of the transmission apparatus according to the first embodiment of the present invention. First, the desired transmission power in each component carrier is calculated (step S101). Next, the CC allowable maximum transmission power is uniformly set in each carrier component according to the number of carrier components to be used (step S102). Subsequently, the PH of the CC allowable maximum transmission power and the required transmission power is calculated (step S103).

In the case of PH report, the mobile terminal transmits a PH report on the component carrier corresponding to the calculated PH report, and the base station identifies the component carrier corresponding to the PH report from the component carrier on which the PH report is transmitted. You may make it do. Alternatively, the mobile terminal transmits a PH report including information indicating the component carrier to which the calculated PH report corresponds in the PH report, and the base station uses the information indicating the component carrier included in the PH report. The PH report may identify the corresponding component carrier. Alternatively, the mobile terminal transmits a PH report including PH reports of all component carriers to be calculated, and the base station acquires a PH report of each component carrier included in the PH report. May be.

In this embodiment, the case where X is determined in the mobile terminal and used for calculating PH has been described. However, the base station determines the allowable maximum transmission power for each CC in consideration of X (that is, P _CC ) The notification is essentially the same.

By correcting the allowable maximum transmission power according to the number of CCs used in this way, there is no mismatch between the actual transmission power and the PH. Therefore, when the terminal performs transmission, it exceeds the PA performance. Thus, no distortion occurs in the transmission signal.

In FIG. 1, although a uniform correction value is given according to the CC to be used, it is not necessarily required to be uniform. For example, since the frequency gain of the antenna is generally not constant, the required communication quality can be maintained at a high antenna gain frequency (CC) even if a large correction value X is given. In addition, there is a possibility that the quality of service (QoS) of data handled by the CC is different. In a CC having a high QoS, the desired communication quality can be satisfied by giving a small correction value X. Thus, the correction value X is not constant for each CC, but may be a fixed value that differs for each CC or may be changed according to QoS.

Next, the PH calculated by each PH calculation unit 107 is input to CC # 1 PUSCH transmission unit 113-1 to CC # 5 PUSCH transmission unit 113-5, respectively. In each PUSCH transmission unit 113, the input PH is transmitted from the physical layer to the upper layer, and then transmitted to the base station using a PUSCH (Physical-Uplink-Shared-CHannel) that is a physical channel for transmitting uplink data. The The output (time signal) of each PUSCH transmission unit 113 is input to the synthesis unit 115, and synthesis (addition) is performed. The processing of the combining unit 115 may be after D / A conversion or before. The output of combining section 115 is transmitted from transmitting antenna section 117 to the base station. In this specification, it is assumed that the synthesis unit 115 includes an amplifier.

Based on the received PH, the base station can determine the number of RBs used in each CC of each terminal, the modulation scheme, and the transmission scheme (SC-FDMA or Clustered DFT-S-OFDM).

As described above, when there is a PA that supports a plurality of CCs, the PH calculation unit 107 of each CC of the terminal corrects the allowable maximum transmission power according to the number of CCs used in the uplink and the QoS of data handled in each CC. Therefore, transmission can be performed in consideration of actual transmission power while maintaining compatibility with LTE.

[Second Embodiment]
In the first embodiment, in the PH calculation unit 107 of each CC, the terminal recognizes the number of CCs used in the uplink and determines the allowable maximum transmission power for each CC, thereby maintaining compatibility with LTE. However, it is possible to perform communication in consideration of the allowable maximum transmission power of all CCs. However, since constant correction is applied to all CCs, there is a case where transmission power control is wasted. Therefore, in the present embodiment, a method for calculating PH in consideration of power actually used in each CC will be described.

FIG. 4 is a block diagram showing a mobile terminal configuration according to the second embodiment of the present invention. The receiving antenna unit 101 inputs the received PDCCH signal to the CC # 1 PDCCH receiving unit 103-1 to CC # 5 PDCCH receiving unit 103-5. Each PDCCH receiving unit 103 inputs control information necessary for calculating the required transmission power to each required transmission power calculating unit 105. Each required transmission power calculation unit 105 calculates the required transmission power in each CC based on the input control information and notifies the required transmission power total unit 201.

The required transmission power total unit 201 performs a process of calculating the total power value P _req input from each required transmission power calculation unit 105. If the required transmission power of the _kth CC is P _k (dBm), the total power P _req (dBm) is expressed by equation (5).

The calculated required transmission power P _req is input to the PH calculation unit 203. The PH calculation unit 203 subtracts the input required transmission power P _req from the allowable maximum transmission power P _CMAX input from the allowable maximum transmission power setting unit 205 to calculate PH. The obtained PH is input as a common value to CC # 1 PUSCH transmission section 113-1 to CC # 5 PUSCH transmission section 113-5.

Each PUSCH transmission unit 113 transmits the input PH from the physical layer to the upper layer, and then transmits the PH to the base station using the PUSCH. The output (time signal) of each PUSCH transmission unit 113 is input to the synthesis unit 115, and synthesis (addition) is performed. The processing of the combining unit 115 may be after D / A conversion or before. The output of combining section 115 is transmitted from transmitting antenna section 117 to the base station.

In this way, in a terminal when there is a PA that supports a plurality of CCs, a PH calculation unit 203 is provided that sums the required transmission power of CCs to be used and subtracts it from the allowable maximum transmission power. By using this, it is possible to perform communication using the performance of the PA efficiently even when the required transmission power is biased in each CC while maintaining compatibility with LTE.

[Third Embodiment]
In the above embodiment, the description has been made on the assumption that the terminal has one PA and all the CCs to be used are supported by one PA. However, although the terminal actually has a plurality of PAs, it is used. A case where the number of PAs is smaller than the number of CCs is conceivable. At this time, if the base station cannot recognize which CC is transmitted by the same PA, there is a possibility that appropriate control cannot be performed. However, if the control information for notifying the base station which CC is transmitted by the same PA from the mobile terminal is defined again, the control information increases, so that the uplink frequency utilization efficiency is lowered. Therefore, this embodiment shows a method in which the terminal notifies the base station of information on the used PA without increasing the amount of LTE control information.

FIG. 5 is a block diagram showing a mobile terminal configuration according to the third embodiment of the present invention. The receiving antenna unit 101 inputs the received PDCCH signal to the CC # 1 PDCCH receiving unit 103-1 to CC # 5 PDCCH receiving unit 103-5. Each PDCCH receiving unit 103 inputs control information necessary for calculating the required transmission power to each required transmission power calculating unit 105. Each required transmission power calculation unit 105 inputs the required transmission power in each CC to the PH calculation unit 301 based on the input control information. FIG. 5 shows an example in which CC # 1 to # 3 use the first PA, and CC # 4 and # 5 use the second PA. Therefore, the outputs of CC # 1 required transmission power calculation unit 105-1 to CC # 3 required transmission power calculation unit 105-3 are input to PH calculation unit 301-1 of the first PA, and CC # 4 required transmission power calculation unit. The outputs of 105-4 and CC # 5 required transmission power calculation section 105-5 are input to PH calculation section 301-2 of the second PA.

Each PH calculation unit 301 calculates PH according to the calculation method of the first embodiment or the calculation method of the second embodiment according to the required transmission power input from each required transmission power calculation unit 105. Since the PH value in LTE is rounded to the nearest value of −23 to 40 dB in 1 dB steps, it becomes a 6-bit sequence. The obtained PHs are respectively input to the first PA information adding unit (amplifier information adding unit) 303-1 and the second PA information adding unit 303-2. In the first PA information adding unit 303-1 and the second PA information adding unit 303-2, information indicating which PA is used to transmit the input PH (hereinafter referred to as PA information) is provided. An additional process is performed. For example, since LTE-A performs communication using a maximum of five CCs, considering that there are five PAs, it is necessary to add 3-bit control information to notify the PA information (5 ≦ 2 ³ ). If new control information is defined, there is a problem that compatibility with LTE is lost. Therefore, it is desired to add PA information while maintaining compatibility with LTE.

The value of PH in LTE is -23 to 40 dB in 1 dB increments and is 64 values, so it is composed of 6 bits. However, since PH is defined by 1 byte (8 bits), the upper 2 bits of 1 byte including the PH of LTE are not used in LTE and are fixed to “00”.

Therefore, consider using two unused bits for PA information. When one CC is transmitted by one PA, “00” is transmitted as the upper 2 bits. When transmitting three or more CCs with one PA, “11” is transmitted as the upper 2 bits. When two CCs are transmitted with one PA, “01” or “10” is transmitted as the upper 2 bits. An example of the above idea is shown in Table 2. Example 1 is a case where CC # 1 to CC # 3 are transmitted by the first PA and CC # 4 and CC # 5 are transmitted by the second PA as shown in FIG. In the section 303-1, "11" is added as the upper 2 bits, and "01" is added as the upper 2 bits in the second PA information adding section 303-2. The base station receives the PH at each CC and checks the upper 2 bits to confirm that CC # 1 to CC # 3 are transmitted using the same PA, and that CC # 4 and CC # 5 have the same PA. Can be used to identify being transmitted. The upper 2 bits of CC # 4 and CC # 5 may be “10”.

In addition, when CC # 4 and CC # 5 are each transmitted by one PA as in Example 2, the upper 2 bits of each PH are “00”, and the base station has CC # 4 and CC # 5 respectively. It can be identified as being transmitted by a different PA. Also, when there are two PAs supporting two CCs as in Example 3 (in Example 3, the first PA and the third PA), the first PA information adding unit 303-1 sets “01”. In addition, the third PA information adding unit 303-3 adds “10” and transmits it. The base station checks the upper 2 bits of PH in each CC, so that CC # 1 and CC # 2 are transmitted using the same PA, and CC # 4 and CC # 5 are transmitted using the same PA. Can be identified. Furthermore, “11” is also added in a PA that supports 4CC or 5CC signals as in Example 4. Moreover, CC transmitted by the same PA like Example 5 does not necessarily need to be CC adjacent on a frequency axis.

In this manner, 1-bit (8-bit) PH is configured by adding 2 bits as PA information to the 6-bit PH output from the PH calculation unit 301 as described above. As a result, PA information can be added without increasing control information while maintaining compatibility with LTE.

The PH output from the first PA information adding unit 303-1 and the second PA information adding unit 303-2 is input to each PUSCH transmission unit 113. FIG. 5 shows an example in which CCs # 1 to # 3 use the first PA and CCs # 4 and # 5 use the second PA, so the first PA information adding unit 303-1 outputs The PH to be input is input to the CC # 1 PUSCH transmission unit 113-1 to CC # 3 PUSCH transmission unit 113-3, and the PH output from the second PA information addition unit 303-2 is the CC # 4 PUSCH transmission unit 113-4, And CC # 5 PUSCH transmission section 113-5. In each PUSCH transmission unit 113, the input PH is transmitted from the physical layer to the upper layer, and then transmitted to the base station using a PUSCH (Physical-Uplink-Shared-CHannel) that is a physical channel for transmitting uplink data. The The output (time signal) of each PUSCH transmission unit 113 is input to the synthesis unit 115, and synthesis (addition) is performed. The processing of the combining unit 115 may be after D / A conversion or before. The output of combining section 115 is transmitted from transmitting antenna section 117 to the base station.

In this way, among the 8-bit control information reserved for PH notification in LTE, the unused upper 2 bits are used for the PA information, so that the base station can maintain compatibility with LTE. It becomes possible to identify which CC is transmitted by the same PA. As a result, the TPC command notified to the terminal by the base station can be determined in consideration of the fact that the same PA is used, so that efficient TPC is possible.

[Fourth Embodiment]
In the present embodiment, the case of adaptively updating the PA information bit sequence added by the PA information adding unit 303 of the third embodiment will be described with reference to the drawings.

FIG. 6 is a block diagram showing a mobile terminal configuration according to the fourth embodiment of the present invention. The receiving antenna unit 101 inputs the received PDCCH signal to the CC # 1 PDCCH receiving unit 103-1 to CC # 5 PDCCH receiving unit 103-5. Each PDCCH receiving unit 103 inputs control information necessary for calculating the required transmission power to each required transmission power calculating unit 105. Each required transmission power calculation unit 105 inputs the required transmission power in each CC to the used PA determination unit (used amplifier determination unit) 401 based on the input control information. Here, the process of the used PA determination unit 401 will be described. Which CC is transmitted by which PA should be determined in consideration of the required transmission power.

FIG. 7A is a diagram showing which PA each CC is transmitted at time t with respect to the fourth embodiment of the present invention (when the number of CCs is 3 and the number of PAs is 2). The height of the spectrum indicates that the required transmission power is high. As shown in FIG. 7A, at time t, CC # 1 has the highest required transmission power and CC # 3 has the lowest required transmission power. Under such circumstances, considering that the input power to the PA is limited, CC # 2 and CC # 3 are transmitted by the same PA, and CC # 1 is transmitted from one PA. Is efficient. Therefore, the used PA determination unit 401 determines the combination of CCs supported by the PA so that the difference in the total transmission power supported by one PA is minimized among the PAs from the required transmission power of each CC.

FIG. 7B is a diagram showing which PA each CC is transmitted at time t + T with respect to the fourth embodiment of the present invention (required transmission power of CC # 3 increases, and among the three CCs). The highest required transmit power). In this case, it is very inefficient to transmit CC # 3 having the highest required transmission power and another CC from the same PA. In this case, the used PA determination unit 401 adaptively changes the combination of CCs supported by one PA depending on the state of the propagation path. As a result, the PA information adding unit 303 changes the upper 2 bits according to the changed usage status of the PA. In this embodiment, it is assumed that there is no performance difference between PAs, but it is also possible to determine CCs supported by one PA in consideration of PA performance differences.

Thus, by determining the CC supported by the PA in consideration of the required transmission power of each CC, it is possible to avoid the transmission power limitation by the PA as much as possible. It becomes difficult to receive power limitation, and TPC operates effectively. As a result, efficient transmission with reduced power consumption at the terminal becomes possible. Further, when the required transmission power varies, the combination of CCs supported by the PA is changed at the timing when the PH is notified to the base station, so that even when the propagation state varies with time, it can be adaptively handled.

105-1 to 105-5 Required transmission power calculation units 107-1 to 107-5, 203, 301-1 to 301-2 PH calculation unit 109 CC allowable maximum transmission power setting unit 115 Combining unit 201 Required transmission power totaling unit 205 Allowable maximum transmission power setting sections 303-1 and 303-2 PA information adding section 401 PA used determining section

Claims

A transmission device that transmits information using a plurality of carrier components,
A smaller number of amplifiers than the number of carrier components;
A required transmission power calculation unit for calculating desired transmission power in each of the carrier components;
An allowable maximum transmission power setting section for setting an allowable maximum transmission power; and
A PH calculation unit that calculates a PH (Power Headroom) between the allowable maximum transmission power and the required transmission power.
The transmission apparatus according to claim 1, wherein the allowable maximum transmission power setting unit uniformly sets the allowable maximum transmission power in each of the carrier components according to the number of carrier components to be used.
The transmission apparatus according to claim 1, wherein the allowable maximum transmission power setting unit sets an allowable maximum transmission power for each carrier component according to a QoS (Quality Of Service) of each carrier component.
A required transmission power total unit that outputs the required transmission power total value by summing the required transmission power values output by the required transmission power calculation unit;
The PH calculation unit
The transmission apparatus according to claim 1, wherein a PH of the allowable maximum transmission power and the total required transmission power is calculated.
The transmission apparatus according to claim 1, further comprising an amplifier information adding unit that adds amplifier information for identifying the amplifier to information output from the PH calculating unit.
The PH calculation unit outputs 6-bit information indicating PH,
6. The transmission apparatus according to claim 5, wherein the amplifier information adding unit adds 2-bit information for identifying the amplifier to the 6-bit information output from the PH calculating unit.
6. The transmission apparatus according to claim 5, further comprising a use amplifier determining unit that determines an amplifier to be used in accordance with a propagation path state.
8. A receiver that receives the amplifier information from the transmitter according to claim 5 and identifies the amplifier to which each carrier component is transmitted based on the amplifier information.
A communication system including a transmission device that transmits information using a plurality of carrier components and a reception device that receives information transmitted from the transmission device,
The transmitter is
A smaller number of amplifiers than the number of carrier components;
A required transmission power calculation unit for calculating desired transmission power in each of the carrier components;
An allowable maximum transmission power setting section for setting an allowable maximum transmission power; and
A PH calculator that calculates a PH (Power Headroom) between the allowable maximum transmission power and the required transmission power;
An amplifier information adding unit for adding amplifier information for identifying the amplifier to the information output by the PH calculating unit;
The receiving device is:
Receiving the amplifier information from the transmitter;
A communication system, wherein an amplifier to which each carrier component is transmitted is identified based on the amplifier information.
A transmission method of a transmission apparatus having a smaller number of amplifiers than the number of carrier components and transmitting information using a plurality of carrier components,
Calculating each desired transmission power in each of the carrier components;
In accordance with the number of carrier components to be used, uniformly setting the maximum allowable transmission power in each of the carrier components;
And calculating a PH (Power Headroom) between the allowable maximum transmission power and the required transmission power.