JP7316161B2 - Mobile terminal equipment, radio base station and radio network system - Google Patents

Description

The present invention relates to a mobile terminal device, a radio base station, and a radio network system using the same, and more particularly to a mobile terminal device, a radio base station, and a radio network system suitable for public broadband mobile communication systems using the VHF band. .

Conventionally, public communication systems such as national and local governments, police, fire departments, and ambulance systems used at the site of a disaster, etc., were mainly voice-based. There is a need for a means for video transmission. Therefore, studies are underway to use part of the VHF band, which has become a vacant frequency due to the digitization of terrestrial television broadcasting, for a public broadband mobile communication system that meets the above objectives. Public broadband mobile communication systems are being specified by the Ministry of Land, Infrastructure, Transport and Tourism (Non-Patent Document 1), and the frequency band is assigned to the 200 MHz band (VHF band from 170 MHz to 202.5 MHz), and the following advantages have

・Since the VHF band prepared exclusively for public institutions (national and local governments, police, fire departments, etc.) is used, prompt disaster prevention and countermeasures are possible.
・The VHF band, which has a long wavelength, has a large wraparound, and is suitable for security and safety applications where minimization of dead zones is required in Japan, which has a complicated topography. Specifically, it enables long-distance transmission with a maximum line-of-sight of 27.8 km (theoretical value) and communication in places where line-of-sight is not possible due to mountains or buildings. In addition, it is not easily affected by the weather, and communication is easy even in heavy rain or heavy snow, for example.
・Communication is possible between a portable base station and a plurality of mobile terminal devices, and a self-employed wireless network that does not depend on a public network can be easily constructed, and can also be connected to an existing IP network.

Ministry of Land, Infrastructure, Transport and Tourism Public Broadband Mobile Communication System Standard Specifications (Kokudentsu No. 56 (established on February 8, 2016))

By the way, looking at the state of radio wave utilization in Japan around the 200 MHz band used by the public broadband mobile communication system, the situation is as shown in FIG. The 12 channels of analog television broadcasting were assigned to the VHF band from 90 MHz to 222 MHz, but not all of that band was used for analog television broadcasting, and the intermediate 108-170 MHz band was reserved for 150 MHz. Allocated to Radio and Broadcaster Liaison Radio. On the other hand, the 200MHz band used by the adjacent public broadband mobile communication system on the high frequency side has an upper limit frequency of 202.5MHz. A guard band of 5 MHz corresponding to . On the other hand, communication radios for broadcasting business are used as a means of communication during emergency reporting and program production. It is positioned as essential for communication. As can be seen from this application, public broadband mobile communication systems and communication radios for broadcasting business are very similar in terms of usage and usage situations, and especially in the event of an emergency or disaster, there is a possibility that both communication traffic congestion will occur at the same time. is high.

The problem here is the relationship between the lower limit frequency (172.5 MHz) of the band allocated for public broadband mobile communication and the upper limit frequency (170 MHz) of the band allocated for contact radio for broadcasting business. Only 2.5 MHz blank band is provided, half of the guard band. As a result, channels on the lower limit frequency side of the 200 MHz band used by public broadband mobile communications are extremely susceptible to radio interference for communication radios for broadcasting business. There is a problem that makes communication difficult. As a result, currently, of the six channels set in the 200 MHz band, public broadband mobile communication systems currently use only three channels on the upper-limit frequency side, effectively utilizing radio wave resources. It's hard to say.

The subject of the present invention is a public broadband mobile communication system that can effectively suppress radio interference to other station frequency bands adjacent to the lower limit frequency side of the 200 MHz band, and in turn, can effectively utilize the radio wave resources of the 200 MHz band. to provide a mobile terminal device, a radio base station, and a radio communication system using them.

In order to solve the above problems, a mobile terminal device of the present invention is a wireless communication device having a transmitting/receiving antenna, and a transmitting front-end unit and a receiving front-end unit that are switchably connected to the transmitting/receiving antenna via an antenna switch. A mobile terminal device for broadcasting business, comprising a front-end circuit and a modulation/demodulation circuit connected to the radio front-end circuit for modulating a transmission wave to a radio base station and demodulating a reception wave from the radio base station. It is used for public broadband mobile communication systems in which a second frequency band from 172.5 MHz to 202.5 MHz adjacent to the upper limit frequency is allocated to the first frequency band from 160 MHz to 170 MHz allocated for contact radio. Furthermore, a power amplifier is provided in the transmission front-end unit and amplifies the transmission modulated waveform signal from the modulation/demodulation circuit and outputs it toward the transmission/reception antenna, and the frequency information of the resource block used for packet transmission is received from the radio base station. specified based on the resource block configuration information, and the resource block belongs to a predetermined suppression target frequency range that includes the lower limit frequency of the second frequency band and is lower than the upper limit frequency in the second frequency band. and a transmission power control unit that controls the transmission power of the power amplifier to be lower than the transmission power of the non-suppressed resource block when the resource block is the resource block to be suppressed. .

Further, the radio base station of the present invention is configured to be connectable to a mobile terminal device via a terminal radio bearer, and has resources for setting resource blocks used for packet transmission from the mobile terminal device on the terminal radio bearer. A radio base station having a block setting unit, which extends from 172.5 MHz to 202.5 MHz adjacent to the upper limit frequency side of the first frequency band from 160 MHz to 170 MHz assigned to communication radio for broadcasting business. A resource block that is used in a public broadband mobile communication system to which a second frequency band is allocated, and whose resource block setting unit creates resource block setting information including frequency information and transmission power information of resource blocks used for packet transmission. A configuration information creation unit and a resource block configuration information transmission unit that transmits the resource block configuration information to the mobile terminal device. When the resource block to be suppressed uses a frequency belonging to a predetermined suppression target frequency range that includes the lower limit frequency of the frequency band and is lower than the upper limit frequency, the transmission power is lower than that of the resource block not to be suppressed. The transmission power information is created as follows.

Further, the wireless network system of the present invention includes: a radio front-end circuit having a transmission/reception antenna; a transmission front-end unit and a reception front-end unit switchably connected to the transmission/reception antenna via an antenna switch; A mobile terminal device connected to an end circuit and having a modulation/demodulation circuit for modulating a transmission wave to a radio base station and demodulating a reception wave from the radio base station, and the mobile terminal device are connected via a terminal radio bearer. and a radio base station having a resource block setting unit configured to set a resource block used for packet transmission from a mobile terminal device on a terminal radio bearer, the radio network system comprising: Used for public broadband mobile communication systems in which a second frequency band from 172.5 MHz to 202.5 MHz adjacent to the upper limit frequency is allocated to the first frequency band from 160 MHz to 170 MHz allocated for communication radio. Further, the resource block setting unit includes: a resource block setting information creating unit that creates resource block setting information including frequency information and transmission power information of resource blocks used for packet transmission; and a resource block setting information transmitting unit for transmitting to the radio base station, the resource block information generating unit of the radio base station, in the second frequency band, the resource block to be used includes the lower limit frequency of the second frequency band and is higher than the upper limit frequency transmission power information is created so that the transmission power is lower than that of non-suppression resource blocks when the suppression target resource block uses a frequency belonging to a predetermined suppression target frequency range that is lower than the , the mobile terminal device has a power amplifier that is provided in the transmission front end unit and that amplifies the transmission modulated waveform signal from the modulation/demodulation circuit and outputs it to the transmission/reception antenna, and based on the resource block setting information received from the radio base station. to specify the frequency and transmission power of the resource block used for packet transmission, and the resource block includes the lower limit frequency of the second frequency band in the second frequency band and is lower than the upper limit frequency. and a transmission power control unit that controls the transmission power of the power amplifier to be lower than that during transmission using a resource block that is not subject to suppression when the resource block is a suppression target resource block that uses a frequency belonging to the frequency range. It is characterized by

The modulation/demodulation circuit of the mobile terminal apparatus selects one from a plurality of modulation schemes including a high-order quadrature amplitude modulation scheme and a quadrature phase modulation scheme with a lower modulation order than the high-order quadrature amplitude modulation scheme at any time. Those configured to perform adaptive modulation of the transmitted wave can be used. In this case, only when the modulation scheme of the suppression target resource block is the high-order quadrature amplitude modulation scheme, the transmission power control unit sets the transmission power of the power amplifier to be lower than that during transmission using the non-suppression resource block. can be configured to control

When six channels with a bandwidth of 5 MHz are set in the second frequency band so as to cover the entire allocated frequency band, the channel whose lower limit frequency of the second frequency band matches the channel lower limit frequency is designated as the first channel. , among the resource blocks set in the frequency band of the first channel, the lowest frequency resource block whose block lower limit frequency matches the channel lower limit frequency can be determined as a resource block to be suppressed.

In the mobile terminal device, a variable attenuator can be provided on the input side of the power amplifier. In this case, the transmission power control unit sets the attenuation rate of the variable attenuator to the minimum value during transmission using resource blocks not subject to suppression, while the output level of the power amplifier is 1 dB during transmission using resource blocks subject to suppression. The attenuation factor of the variable attenuator can be adjusted so as to attenuate as much as possible.

In addition, the reception front-end unit is configured as a band-pass filter that includes the allocated frequency band for public broadband mobile communication from 172.5 MHz to 202.5 MHz in the pass band, and is adjacent to the lower limit frequency side of the allocated frequency band. A low-band interference wave blocking filter can be provided for blocking communication waves of communication radios for broadcasting business using a frequency band from 160 MHz to 170 MHz as low-band side interference waves. The low-band interference wave blocking filter can be configured as a SAW filter with an attenuation of 30 dB or more and 70 dB or less at 170 MHz. As the SAW filter, a filter having an insertion loss in the passband of 5 dB or more and 15 dB or less can be adopted. A main low-noise amplifier that amplifies a received wave signal received by the transmitting/receiving antenna can be provided between the antenna switch and the low-band interference wave blocking filter. Furthermore, a compensating low-noise amplifier can be provided on the output side of the SAW filter to compensate for the insertion loss of the received signal due to the SAW filter by amplifying the received wave signal after passing through the SAW filter.

In the present invention, frequency information of a resource block used for packet transmission of a mobile terminal device is specified based on resource block setting information received from a radio base station, and the resource block is specified in the second frequency band in the second frequency band. In the case of a suppression target resource block that uses a frequency belonging to a predetermined suppression target frequency range that includes the lower limit frequency of two frequency bands and is lower than the upper limit frequency, the transmission power by the power amplifier is transferred to a resource that is not subject to suppression. It is controlled so that it is smaller than when it is transmitted by block. As a result, when building a public broadband mobile communication system in the 200 MHz band, there is a problem of radio interference to other station communication waves in the above band on the lower limit frequency side (specifically, communication waves of communication radio for broadcasting business), especially It is possible to effectively suppress the influence of spurious interference originating from the third harmonic of the transmission wave, and as a result, it is possible to effectively utilize radio wave resources in the 200 MHz band.

1 is a block diagram showing an overview of the configuration of a wireless communication system according to the present invention; FIG. FIG. 2 is a block diagram showing an example of an electrical configuration of a portable base station device; 1 is a block diagram showing an example of the electrical configuration of a mobile terminal device of the present invention; FIG. FIG. 2 is a block diagram showing an electrical configuration of a radio communication section of a radio base station section; 5 is a graph showing pass characteristics of the SAW filter used in the embodiment; FIG. 4B is a block diagram showing an example of the electrical configuration of the modulation section of the wireless communication section in FIG. 4A; FIG. 4B is a block diagram showing an example of the electrical configuration of the demodulator of the wireless communication unit in FIG. 4A; A conceptual diagram of an IP packet. FIG. 2 is a diagram conceptually showing a protocol stack of a 3GPP control plane; FIG. 2 is a diagram conceptually showing a protocol stack of a 3GPP user plane; FIG. 2 is a diagram conceptually showing 3GPP downlink channel mapping; FIG. 4 is a diagram conceptually showing uplink channel mapping. FIG. 2 is a conceptual diagram showing the relationship between frequency band channels and resource blocks; FIG. 2 is an explanatory diagram showing a communication frequency allocation situation in the VHF band; FIG. 4 is a diagram for explaining the relationship between output saturation of a power amplifier and waveform distortion; FIG. 10 is a diagram for explaining the channel allocation of the second frequency band together with the setting of the output spectral density level and the transmission spurious standard; 5 is a graph showing the relationship between input/output characteristics of a power amplifier and third harmonics; The figure which shows an example of a CQI table. FIG. 2 is a communication flow diagram showing the flow of transmission power control processing of a mobile terminal device in an example of the wireless communication system of the present invention; FIG. 19 is a diagram showing a processing flow of a modified example that replaces part of the communication flow diagram of FIG. 18; The figure which shows the processing flow of another modification similarly.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments for carrying out the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a schematic diagram conceptually showing an example of a wireless communication system according to the present invention. The wireless communication system 50 follows a communication protocol stack of a system defined by 3GPP (in this embodiment, LTE is used, but other systems such as WiMAX may be used), and a plurality of It is configured to perform radio communication between UEs (mobile terminals) 5 .

The portable base station device 1 of the wireless communication system 50 is installed at the site of a disaster or the like, and constructs a public broadband mobile communication system capable of video transmission for sharing accurate information on the disaster area. A 200 MHz VHF band, that is, a band from 172.5 MHz to 202.5 MHz, is allocated as a frequency band for use in the public broadband mobile communication system. As will be described later, the portable base station device 1 can procure power supply voltage from a battery, a private power generator, or the like, and can easily construct a self-employed wireless network that does not depend on a public network. The UE 5 is carried by an active person of the portable base station device 1 and is connected to the portable base station device 1 by a radio bearer 57 .

The portable base station device 1 is wired-connected to a radio base station section (eNodeB (evolved NodeB (radio base station)) 4) and to the radio base station section 4, and an EPC (Evolved Packet Core) function unit 3. The EPC function unit 3 includes an MME (Mobility Management Entity) 2 serving as a control plane side gateway, an S-GW (Serving Gateway) 6 serving as a user plane side gateway, and an upstream side It has a P-GW (PDN (Packet Data Network) Gateway) 7 which is located at a node with a network element (here, router 8) and performs IP address management toward the upstream network element side. (For example, by satellite communication) or by wire connection to the external network 60, and acquires content data such as moving images (video) to be distributed by public broadband communication.

On the control plane side, the radio base station unit (eNodeB) 4 is connected to the MME 2 via the S1-MME interface. Also, on the user plane side, the radio base station unit 4 is connected to the S-GW 6 via the S1-U interface. S-GW6 is connected to P-GW7 via an S5 interface.

FIG. 2 is a block diagram showing an example of the electrical configuration of the portable base station device 1. As shown in FIG. The EPC function unit 3 is mainly composed of microcomputer hardware, and includes a CPU 301, a RAM 302 serving as a program execution area, and a mask ROM 303 (permanently storing firmware for microcomputer hardware peripheral control that does not require rewriting; hereinafter, etc.) and a bus 306 or the like that interconnects them. Also, a flash memory 305 is connected to the bus 306, and communication firmware 305a including an LTE protocol stack for EPC is used here. Each program of an MME entity 305b, an S-GW entity 305c, and a P-GW entity 305d that virtually realizes functions is installed.

The bus 306 is also connected to an upstream communication interface 304A and a downstream communication interface 304B. An input/output port for IP packets for the P-GW is secured in the upstream side communication interface 304A, and an input/output port for IP packets for the S-GW is secured in the downstream side communication interface 304B. In the above configuration, the MME 2, S-GW 6, and P-GW 7 in FIG. 2 are configured as virtual functional blocks realized by software on computer hardware, but each is configured by independent hardware logic. You may

The wireless base station unit 4 is mainly composed of microcomputer hardware, and includes a CPU 401, a RAM 402 serving as a program execution area, a mask ROM 403, a bus 406 interconnecting them, and the like. A flash memory 405 is connected to the bus 406, and communication firmware 405a including the LTE protocol stack for the wireless base station is stored therein. Also, the bus 406 is connected with a radio communication unit 412 for radio connection with the UE 5 by constructing a radio bearer, and a communication interface 404 . The communication interface 404 is connected to the communication interface 304 of the EPC function unit 3 via the wired communication bus 31 .

Next, the portable base station device 1 includes a detachable secondary battery module 21 (for example, a lithium ion secondary battery module, a nickel hydrogen secondary battery module, etc.), a radio base station section 4 and an EPC function section 3. It has a structure in which a circuit block and a power supply circuit unit 22 that converts an input voltage from a secondary battery module 21 into a drive voltage for each circuit block and outputs the voltage are integrally assembled in a portable housing 23 . As a result, the portable base station device 1 can autonomously procure the driving power supply voltage from the secondary battery module 21, and can be installed in locations where external power supply voltage such as commercial AC is unavailable (for example, disaster areas with power outages). can also be used without problems. The portable housing 23 has a box shape made of metal or reinforced resin.

When the output voltage of the secondary battery module 21 drops due to discharge, the secondary battery module 21 is removed from the portable housing 23 and mounted on a dedicated charger connected to, for example, a commercial AC power supply (not shown) or a private power generator. It is possible to charge by In addition, the power supply circuit unit 22 can also receive external power supply voltage from the above-mentioned commercial alternating current, a private power generator, or a power supply lid of a battery-equipped vehicle such as an electric vehicle or a hybrid vehicle. Conversion output is possible. Furthermore, it is also possible to configure such that the secondary battery module 21 can be charged by the external power supply voltage. For example, when the power supply circuit unit 22 is receiving power from a commercial alternating current or the like and the power supply is interrupted due to a power failure, the operation of the portable base station device 1 can be continued by switching to power reception from the secondary battery module 21. It can also be configured to be

FIG. 3 is a block diagram showing an example of an electrical configuration of a UE (mobile terminal device) 5. As shown in FIG. UE5 is comprised as the smart phone provided with the microcomputer 100 as a processing subject. The microcomputer 100 includes a CPU 101, a RAM 102 serving as a program execution area, a ROM 103, an input/output unit 104, and a bus 106 interconnecting them. A flash memory 105 is connected to the bus 106, and an OS 105s for building an operating environment for the UE 5, communication firmware 105a including an LTE protocol stack for the UE, and the like are installed.

A monitor 109 is connected to the input/output unit 104 via a graphic controller 1091 . A touch panel 110 forming an input unit is superimposed on the monitor 109, and cooperates with various software operation units displayed on the monitor 109 to input various information necessary for controlling the operation of the UE 5. there is The monitor 109 functions as playback means for moving images (video) distributed via a public broadband communication system. A touch panel 110 is connected to the input/output unit 104 via a touch panel controller 1101 . A camera 111 for capturing still images or moving images is connected to the input/output unit 104 . Furthermore, a wireless communication unit 500 is connected to the bus 106 . The UE 5 is wirelessly connected to the radio base station section 4 of the radio communication unit 1 of FIG.

FIG. 4A is a block diagram showing an example of an electrical configuration of wireless communication section 500. As shown in FIG. A wireless communication unit 500 includes an interface unit 501 for inputting and outputting digital signals to and from the bus 106 of the microcomputer hardware 100 shown in FIG. and a transmitting block 550, a transmitting/receiving antenna 505, and an antenna that receives a transmitting/receiving switching signal from the microcomputer hardware 100 side and selectively connects the receiving block 510 and the transmitting block 550 to the transmitting/receiving antenna 505. and a switch 504 . Receiver block 510 and transmitter block 550 use multiple modulation and demodulation schemes to perform adaptive modulation, such as Quadrature Phase Shift Keying (QPSK), Higher Order Quadrature Amplitude Modulation (16QAM), 64QAM: 16 Quadrature Amplitude Modulation), etc., but since the configurations of these modulation/demodulation circuits are well-known, the QPSK modulation/demodulation circuit will be described as a representative here.

The transmission-side block 550 includes a modulation circuit 700 that generates an analog transmission wave signal by modulating a carrier wave using the serial transmission data signal input from the interface unit 501 as a baseband signal, and a modulation circuit 700 that amplifies the analog transmission wave signal for transmission and reception. A transmit front end 730 is provided that feeds the antenna 505 . The receiving block 510 also includes a reception front end section 630 that extracts and amplifies a desired wave from the antenna reception signal, and demodulates the received wave signal output from the reception front end section 630 into a baseband signal and converts it into serial reception data. A demodulation circuit 600 for conversion is provided. The transmission front-end section 730 and the reception front-end section 630 constitute a radio front-end circuit. Also, the modulation circuit 700 and the demodulation circuit 600 constitute a modulation/demodulation circuit.

FIG. 5 shows a configuration example of the modulation circuit 700. A serial/parallel converter 720 separates the waveform of a serial transmission data signal into two-channel (Ich/Qch) parallel bit signals, which are then D/A converted. It is converted into an analog baseband signal via units 717 and 719 and low-pass filters 716 and 718 . Multipliers 713 and 715 convert the analog baseband signal of each channel into a sinusoidal carrier wave from an oscillator circuit 712 consisting of a voltage-controlled oscillator circuit VCO and a phase-locked loop circuit PLL. are converted into quadrature frequency-modulated waves by a duplexer 721 and output as an analog transmission wave signal to a transmission front end section 730 (FIG. 4A).

FIG. 6 shows an example of the configuration of demodulation circuit 600. Multipliers 613 and 615 convert the analog received wave signal from reception front-end section 630 into a sine wave demodulated signal from transmission circuit 612 (one of which is a phase-shifted signal). is advanced by 90° by the unit 614) to obtain Ich and Qch baseband signals. These baseband signals are further converted into parallel bit signals by low-pass filters 616, 618 and A/D converters 617, 619, further converted into serial received data signals by a parallel/serial conversion section 620, and converted to the interface section of FIG. 4A. 501 is output.

Returning to FIG. 4A , transmission front end section 730 adjusts the input level of the analog transmission wave signal from modulation circuit 700 by variable attenuator 551 , amplifies it by power amplifier 553 , and passes it through bandpass filter 552 . , the antenna switch 504 and the antenna 505, and output as a transmission wave. On the other hand, reception front-end section 630 amplifies the reception wave received by antenna 505 with main low-noise amplifier 513 , passes it through bandpass filter 511 , and outputs it to demodulation circuit 600 as an analog reception wave signal. The attenuation rate of the variable attenuator 551 receives a transmission power switching signal from the microcomputer hardware side, and is switched according to the type of resource block at the time of packet transmission as will be described later. Details will be described later.

An outline of the LTE communication system will be described below.
FIG. 7 is a schematic diagram showing the structure of an IP packet used for data transmission between the UE 5 and the portable base station device 1. As shown in FIG. An IP packet 1300 is composed of an IP header 1301 and a payload 1302. In the IP header 1301 are written a PDU identification number, a data source address 1301a, a data destination address 1301b, and the like. 8 and 9 show radio protocol stacks in the LTE system, with FIG. 8 showing a user plane protocol stack and FIG. 9 showing a control plane protocol stack. The wireless protocol stack is partitioned into layers 1 to 3 of the OSI reference model, with layer 1 being the PHY (physical) layer. Layer 2 includes a MAC (Medium Access Control) layer, an RLC (Radio Link Control) layer, and a PDCP (Packet Data Convergence Protocol) layer. Layer 3 includes an RRC (Radio Resource Control) layer and a NAS (Non-Access Stratum) layer.

The role of each layer is as follows.
PHY layer: Performs encoding/decoding, modulation/demodulation, antenna mapping/demapping, and resource mapping/demapping. Data and control signals are transmitted via physical channels between the PHY layer of the UE 5 and the relay wireless communication unit 9 and the PHY layer of the wireless base station unit (eNodeB) 4 .
MAC layer: Performs data priority control, retransmission control processing by HARQ, random access procedure, and the like. Data and control signals are transmitted between the MAC layer of the UE 5 and the MAC layer of the radio base station unit 4 via a transport channel. The MAC layer of the radio base station unit 4 includes a scheduler that determines uplink and downlink transport formats (transport block size, modulation and coding scheme (MCS)) and resource blocks to be allocated to the UE 5 .

• RLC layer: uses functions of the MAC layer and the PHY layer to transmit data to the RLC layer of the receiving side. Data and control signals are transmitted between the RLC layer of the UE 5 and the RLC layer of the radio base station unit 4 via logical channels.
- PDCP layer: Performs header compression/decompression and encryption/decryption of PDUs.
• RRC layer: defined only in the control plane that handles control signaling. A message (RRC message) for various settings is transmitted between the RRC layer of the UE 5 and the RRC layer of the radio base station unit 4 . The RRC layer controls the logical, transport and physical channels according to the establishment, re-establishment and release of radio bearers. If there is a connection (RRC connection) between the RRC of the UE 5 and the RRC of the radio base station unit 4, the UE 5 is in RRC connected mode, otherwise it is in RRC idle mode.

These layers are used in both the control plane and the user plane. On the other hand, only the control plane, the UE 5 and the MME 2 are provided with a NAS layer that performs session management, mobility management, etc. above the RRC layer. A GTP-U (GPRS (General Packet Radio Service) Tunneling Protocol for User Plane) layer is provided in the user data transmission interface between the radio base station unit 4 and the EPC function unit 3 side. The GTP-U layer is for identifying the UE 5 to be connected and identifying the radio bearer to be used.

Next, FIG. 10 shows downlink channel mapping in the LTE system. Here, the mapping relationship among logical channels (Downlink Logical Channels), transport channels (Downlink Transport Channels) and physical channels (Downlink Physical Channels) is shown. They will be described in order below.
- DTCH (Dedicated Traffic Channel) is a dedicated logical channel for the transmission of data. The DTCH is mapped to a DLSCH (Downlink Shared Channel), which is a transport channel.
DCCH (Dedicated Control Channel): A logical channel for transmitting dedicated control information between the UE 5 and the network. DCCH is used when UE 5 has an RRC connection with radio base station unit 4 . DCCH is mapped to DLSCH.
• CCCH (Common Control Channel): a logical channel for transmission control information between the UE 5 and the relay radio communication unit 9 and the radio base station unit 4 . CCCH is used when UE 5 does not have an RRC connection with radio base station unit 4 . CCCH is mapped to DLSCH.

BCCH (Broadcast Control Channel): Logical channel for system information distribution. The BCCH is mapped to a transport channel BCH (Broadcast Channel) or DLSCH.
PCCH (Paging Control Channel): A logical channel for notifying paging information and system information changes. PCCH is mapped to PCH (Paging Channel) which is a transport channel.

Also, the mapping relationship between transport channels and physical channels is as follows.
DLSCH and PCH: mapped to PDSCH (Physical Downlink Shared Channel). DLSCH supports HARQ, link adaptation and dynamic resource allocation.
BCH: Mapped to PBCH (Physical Broadcast Channel).

Next, FIG. 11 shows uplink channel mapping in the LTE system. Similar to FIG. 8, it shows the mapping relationship between logical channels (Downlink Logical Channels), transport channels (Downlink Transport Channels) and physical channels (Downlink Physical Channels). They will be described in order below.

CCCH (Common Control Channel): A logical channel used to transmit control information between the UE 5 and the EPC function unit 3, and the EPC function unit 3 and radio resource control (RRC: Radio Resource Control) used by UEs 5 that do not have a connection.
DCCH (Dedicated Control Channel): A one-to-one (point-to-point) bidirectional logical channel, used to transmit individual control information between the UE 5 and the EPC function unit 3 channel. A dedicated control channel DCCH is used by UEs 5 that have an RRC connection.
• DTCH (Dedicated Traffic Channel): A one-to-one bi-directional logical channel, dedicated to a particular UE or relay radio, used for the transfer of user information.

ULSCH (Uplink Shared Channel: HARQ), dynamic adaptive radio link control, and discontinuous transmission (DTX: Discontinuous Transmission) are supported transport channels.
RACH (Random Access Channel): transport channel in which limited control information is transmitted.

PUCCH (Physical Uplink Control Channel): response information for downlink data (ACK (Acknowledge) / NACK (Negative acknowledge)), downlink radio quality information (CQI: Channel Quality Indicator), and, It is a physical channel used to notify the radio base station unit 4 of an uplink data transmission request (scheduling request: SR).
- PUSCH (Physical Uplink Shared Channel): A physical channel used to transmit uplink data.
PRACH (Physical Random Access Channel): A physical channel mainly used for random access preamble transmission for acquiring transmission timing information (transmission timing command) from the UE 5 to the radio base station unit 4. Random access preamble transmission is performed within the random access procedure.

As shown in FIG. 11, in the uplink, mapping between transport channels and physical channels is performed as follows. The uplink transmission/reception channel ULSCH is mapped to the physical uplink transmission/reception channel PUSCH. A random access channel RACH is mapped to a physical random access channel PRACH. A physical uplink control channel PUCCH is used as a physical channel alone. Also, the common control channel CCCH, the dedicated control channel DCCH, and the dedicated traffic channel DTCH are mapped to the uplink transmission/reception channel ULSCH.

Next, in the downlink of the LTE system, the UE 5 wirelessly connects to the radio base station unit 4 by OFDM (Orthogonal Frequency-Division Multiplexing) access (OFDMA). The OFDMA system is characterized as a two-dimensional multiplexed access system that combines frequency division multiplexing and time division multiplexing. Specifically, the orthogonal frequency axis and time axis subcarriers are divided and allocated to UE 5, and the orthogonal subcarriers on the frequency axis are divided so that the signal of each subcarrier is zero (0 points). . By dividing subcarriers and allocating them on the frequency axis, even if a subcarrier is affected by fading, it is possible to select another subcarrier that is not affected by fading. There is an advantage that subcarriers can be used and radio quality can be maintained.

Then, in the OFDMA system, a resource block (RB) defined on a virtual plane formed by a frequency axis and a time axis is adopted as a radio resource. As shown in FIG. 12, RBs are defined as blocks obtained by dividing the plane into a matrix at 180 kHz/0.5 msec, and each resource block RB includes 12 subcarriers adjacent to each other at intervals of 15 kHz on the frequency axis. The above includes one slot (7 symbols) of the frame. This RB is assigned to UE5 with two adjacent RBs (1 msec) on the time axis as one set. On the other hand, also in the uplink of the LTE system, resource blocks RB with a similar concept are used as radio resources, except that SC-FDM (Single Career Frequency-Division Multiplexing) access (SC-FDMA) is adopted. In OFDMA, one resource block is divided into 12 subcarriers (bandwidth: 15 kHz) on the frequency axis, whereas SC-FDMA is a single-carrier system in which division into subcarriers is not performed.

For example, allocation of resource blocks to the downlink is determined by the following procedure in a normal LTE protocol. The UE 5 and the relay radio communication unit 9 receive the CQI reference signal transmitted from the eNodeB 4 for each predetermined frequency unit, measure the CQI, which is an indicator indicating the reception quality of the downlink channel, and create CQI information. . As shown in FIG. 17, the CQI information represents the reception quality obtained by measurement with two parameters, the coding rate and the frequency utilization efficiency, for each modulation scheme. is reported from UE5 to eNodeB4 using the CQI index. The eNodeB 4 allocates resource blocks to radio bearers with individual UEs 5 based on the CQI information notified from a plurality of UEs 5 . By optimally allocating a frequency block with a high received signal level to each UE 5 according to the content of the CQI information of each UE 5, the diversity effect (multi-user diversity) of UE 5 can be obtained, user throughput and Throughput per cell can be improved.

As shown in FIG. 12, the above-described scheduler operating on the MAC layer, as shown in FIG. In constructing the bearer 57, resource block RB allocation control is performed according to the scheme of FIG. In the radio base station unit 4 of FIG. 3, the carrier frequency and modulation method for the voltage control oscillator circuit VCO of the modulation unit 700 and the demodulation unit 600 in FIGS. A setting instruction is given.

Then, even when CH1 whose lower limit frequency (172.5 MHz) of the assigned frequency band matches the lower limit frequency of the channel is used, the scheduler schedules assignment by selecting all resource blocks set in the channel. Execute. Further, in FIG. 12, the lowest frequency source block EB whose block lower limit frequency matches the channel lower limit frequency is determined as a resource block to be suppressed, and when the resource block to be suppressed is assigned to construct the radio bearer 57, As the resource block configuration information for UE5, in addition to the specific information of the suppression target resource block (the position of the resource block in FIG. 12), resource blocks other than the lowest frequency source block EB (resource blocks not to be suppressed) The transmission power setting information is created so as to be lower than when used, and transmitted to the UE 5 as broadcast information on the PUCCH.

In UE5, the frequency information of the resource block used for packet transmission is specified based on the resource block setting information, and when the resource block is a resource block to be suppressed, the transmission power by the power amplifier 553 is suppressed. It is controlled so that it becomes smaller than when it is transmitted by the resource block outside (transmission power control section). The details will be described below.

As shown in FIG. 13, the second frequency band, which is the allocated frequency band for public broadband mobile communication, has six channels (CH1 to CH6: center frequencies of 175, 180, 185, 190, 195 and 200 MHz, each with a bandwidth of 5 MHz) are set. The communication system 50 (FIG. 1) of the present embodiment adopting the LTE system is configured so that all six channels can be used, and the lower limit frequency (172.5 MHz) of the second frequency band matches the channel lower limit frequency. When using CH1 (first channel), as described above, all resource blocks set in this channel, including the lowest frequency resource block EB, are used for communication. Since this lowest frequency resource block EB has a very narrow frequency interval of 2.5 MHz with respect to the first frequency band, which is the band allocated for communication radio for broadcasting business, it is very likely to cause radio interference to the first frequency band. In this case, a particular problem is spurious emission due to the third harmonic of the transmission wave when the lowest frequency resource block EB is used.

Specifically, as shown in FIG. 14, the power amplifier 553 (FIG. 4A) that amplifies the transmission wave has a shape in which the top of the waveform collapses when the transmission power is set beyond the linear region of the input/output characteristics. distorted by This waveform distortion produces harmonics of the fundamental wave. Of these, the third harmonic has the highest intensity level, and appears relatively close to both sides of the frequency of the fundamental wave. Then, the spurious level to the side of the first frequency band with a narrow frequency interval increases, leading to radio interference.

FIG. 15 shows an overview of the spurious standards in the public broadband mobile communication system using the second frequency band, and shows the transmission power density (vertical axis) level of each channel in a bar graph. It can be seen that the upper limit value (gray solid line) of the spurious level in the blank band between the frequency bands is -30 dBm/100 kHz, which is a very strict value.

As shown in FIG. 16, in the input/output characteristics of the power amplifier 553, the fundamental wave is not distorted and maintains linearity up to a certain upper limit input level. The generation loses linearity and bends the characteristic curve to the low power side. The figure also shows the level change of the 3rd harmonic component with respect to the input level. 3 times). This is because the level of the third harmonic is mathematically proportional to the cube of the level of the fundamental wave. The intersection of the extension of the input/output straight line of the linear region of the fundamental wave and the straight line representing the third harmonic wave level is called the third order intercept point. This means that it can be maintained up to An operating point at which the actual output is reduced by 1 dB with respect to the extension of the linear region of the fundamental wave is called a 1 dB compression point. The power amplifier 553 is basically operated at an input level lower than this 1 dB compression point, and its input level is usually adjusted to fall within the range of 60 to 70% of the level corresponding to this 1 dB compression point. be done. However, even with such a setting, the instantaneous value of the input level may approach or slightly exceed the 1 dB compression point, causing the third harmonic to occur. In particular, when high-order quadrature amplitude modulation such as 16QAM or 64QAM is adopted as the modulation method, it has been found that the generation of third-order harmonics due to excessive input is particularly likely to occur.

Therefore, in the present embodiment, as a countermeasure for reducing spurious emissions during packet transmission by the UE 5, processing for adjusting the transmission power of the UE 5 is performed according to the processing flow shown in FIG. When the UE 5 issues an attach request to the radio base station unit 4 at U1, a well-known attach sequence is executed among the UE 5, the radio base station unit 4 and the EPC function unit 3 at U2 to set up a radio bearer. Next, the process shifts to a specific packet transmission procedure. First, in U3, a reference signal for CQI measurement is transmitted from the radio base station unit 4 to UE5. UE5 receives this, performs a CQI measurement, and returns the measurement result in the form of a CQI index (Fig. 17) at U5.

The radio base station unit 4 refers to the CQI measurement results from all connected UEs and determines a resource block allocation schedule (that is, which resource block is allocated to which UE). In U7, it is determined whether or not the resource block to be allocated to UE5 corresponds to the above suppression target resource block. If not applicable (that is, if the resource block is not subject to suppression), proceed to U9 to set the transmission power to normal. Specifically, to the variable attenuator 551 in FIG. 4A, a transmission power switching signal specifying the minimum value as the attenuation rate of the input signal to the power amplifier 553 is output, and the transmission power is set to the normal setting.

On the other hand, in U7, if the resource block to be allocated corresponds to a suppression target resource block, the process proceeds to U10, and the transmission power is set to be suppressed. Specifically, a transmission power switching signal is output to the variable attenuator 551 of FIG. 4A so that the attenuation rate exceeds the minimum value, and the transmission power is suppressed. The generation level of the third harmonic changes in proportion to the cube of the transmission power level of the fundamental wave. Therefore, by lowering the transmission power level of the fundamental wave by, for example, 1 dB, the spurious emission level derived from the third harmonic can be reduced by 3 dB (30 times). In this case, it is desirable to set the attenuation rate of the variable attenuator 551 so that the instantaneous maximum value of the input level of the power amplifier 553 falls below the level corresponding to the 1 dB compression point.

At U11, the radio base station unit 4 creates resource block setting information including the position of the allocated RB, the modulation scheme, and the transmission power setting instruction value, and transmits it to the UE 5 at U12. The UE 5 receives this and refers to the resource block setting information in U13 to set the frequency/modulation scheme corresponding to the allocated resource block and further set the transmission power.

Regarding the specific reduction rate of the transmission power level (attenuation rate of the variable attenuator 551), the radio base station unit 4 determines the number of UEs currently connected in the coverage area and the frequency of use of suppression target resource blocks for each UE. can be set and determined dynamically. For example, a method is conceivable in which the greater the number of UEs in communication using suppression target resource blocks in an area, the greater the transmission power level reduction rate is set. In the case of the general LTE protocol, the transmission power level is specified on the radio base station unit 4 side, and the value is incorporated into the resource block setting information and transmitted to the UE 5 as described above. Therefore, the UE 5 may passively set the transmission power according to the setting value included in the resource block setting information.

On the other hand, as a simpler method, it is also possible to always suppress the transmission power level at a constant reduction rate when using suppression target resource blocks. In this case, the same method as above can be adopted, but the UE5 side specifies only the frequency and modulation scheme corresponding to the allocated resource block by the resource block setting information, and the UE5 side allocated resource block is a resource block to be suppressed. It is also possible to determine whether the transmission power level is switched or not at the same time.

With the above configuration, when a public broadband mobile communication system is constructed in the 200 MHz band as described above, at the time of packet transmission using the lowest frequency resource block by UE5, interference due to spurious emissions to the communication radio for broadcasting business is effectively It is clear that the In addition, due to concerns about this interference, active use of the three channels on the low frequency side of the six channels in the 200 MHz band has been postponed until now in public broadband mobile communications. 2 channels can be utilized without any problem, and the effective utilization of radio wave resources in the 200 MHz band can be achieved.

Next, in this embodiment, as shown in FIG. 4A, the reception front end section 630 is provided with a band-pass filter 511 that serves as a low-band interference wave blocking filter. As a result, interfering waves from the communication radio band for broadcasting business can be effectively blocked, and high-quality reception at the UE 5 becomes possible. In FIG. 12, even when the lowest frequency source block EB is assigned to construct the radio bearer 57, the interfering waves from the communication radio band for broadcasting business are effectively blocked, enabling high-quality reception at the UE 5. . This will be explained below.

The specifications of the bandpass filter 511 are such that the desired wave on the public broadband mobile communication side is not excessively attenuated (for example, within 15 dB), and the communication wave of the communication radio for broadcasting business, which is 2.5 MHz away from the low frequency side, is sufficient ( For example, it is required to have a steep pass characteristic that can be attenuated to 25 dB or more. However, the wavelength of communication waves in the 200 MHz band is as large as about 75 cm, and for example, cavity filters with deep attenuation and steep pass characteristics are extremely large in size. cannot be incorporated into

Therefore, in this embodiment, a SAW (Surface Acoustic Wave) filter (hereinafter also referred to as SAW filter 511) is employed as the bandpass filter 511 (low-band side interference wave blocking filter) in FIG. 4A. A SAW filter has a structure in which comb-shaped electrodes are arranged opposite to each other on a piezoelectric substrate, and a high-frequency signal input as an electric signal is applied to the surface by the piezoelectric effect of the piezoelectric substrate. converted into waves. A desired frequency component contained in the surface acoustic wave is extracted as it propagates on the piezoelectric substrate, and is taken out again as an electric signal. The passband width and center frequency of the filter can be variously adjusted by the structural period of the comb-shaped electrodes and the physical properties of the piezoelectric body and electrodes. By adopting a SAW filter, the band-pass filter 511 (low-band side interference wave blocking filter) can be reduced in size to the extent that it can be incorporated as a surface-mounted element in a mobile terminal device even in the frequency band with a large wavelength as described above. is.

The SAW filter 511 should preferably have an attenuation of 25 dB or more in the vicinity of 170 MHz, which corresponds to the upper limit frequency of the band allocated for communication radio for broadcasting business. If the attenuation at this frequency is less than 25 dB, the effect of blocking interference waves on the low frequency side is not sufficient. Although there is no particular limitation on the upper limit of this attenuation amount, for example, the upper limit of about 70 dB can be set. On the other hand, it is desirable that the attenuation at 172.5 MHz, which corresponds to the lower limit frequency of the 200 MHz band, is 15 dB or less. FIG. 4B is a graph showing the pass characteristic of the SAW filter used in this embodiment, and the attenuation characteristic at 170 MHz is as steep as about 40 dB. By adopting such a SAW filter 511 with a deep and steep attenuation characteristic, it is possible to effectively improve the reception blocking characteristics (especially the reception characteristics of CH1 (center frequency: 175 MHz)) due to the transmission power of communication radio for broadcasting business. .

When the SAW filter 511 as described above is employed, the attenuation of the desired signal within the passband increases to 5 dB or more and 15 dB or less (for example, 10 dB). On the other hand, background noise (mainly thermal noise, for example) with respect to the desired signal may remain at the same level without being attenuated even if it passes through the SAW filter 511. In this case, the NF (noise figure) of the desired signal is create aggravating problems. Therefore, as shown in FIG. 4A, the aforementioned main low noise amplifier 513 for amplifying the received wave signal received by the transmitting/receiving antenna 505 is placed between the antenna switch 504 and the SAW filter 511 (low-band interference wave blocking filter). On the output side of the SAW filter 511 , a compensating low noise amplifier 512 that amplifies the received wave signal after passing through the SAW filter 511 to compensate for the insertion loss of the received signal by the SAW filter 511 can be provided. By providing such a compensating low-noise amplifier 512, it is possible to compensate for the attenuation of the desired signal due to the insertion loss of the SAW filter 511, and effectively solve the problem of deterioration of NF. The gain of the compensating low noise amplifier 512 is preferably set to about 0.5 to 2 times the insertion loss level of the SAW filter 511 . A plurality of SAW filters with low attenuation factors can be cascaded and used.

Although the embodiment of the present invention has been described above, it is merely an example, and the present invention is not limited to this. For example, when the modulation/demodulation circuit is configured to perform adaptive modulation as described above, the modulation scheme of the resource block to be suppressed is a high-order quadrature amplitude modulation scheme, specifically 16QAM, which is particularly susceptible to third harmonics. Only in the case of the higher-order QAM modulation described above, it is possible to control the transmission output of the power amplifier so as to be smaller than that during transmission using resource blocks that are not subject to suppression. In this case, the processing flow of FIG. 18 is obtained by replacing the steps U7, U9, and U10 with those shown in FIG. That is, if the allocated resource block is a suppression target resource block in U7, it is further determined in U8 whether or not the modulation scheme is high-order QAM modulation. Then, in the case of high-order QAM modulation, the process advances to U10 to set the transmission output to be suppressed. On the other hand, if it is not high-order QAM modulation (for example, if it is QPSK), proceed to U9 and set the transmission power to normal. If the effects of spurious emissions are unique to high-order QAM modulation only, this scheme improves user throughput by not suppressing transmit power when other modulation schemes with less impact are employed. have the advantage of In this case, as shown in FIG. 20, when the resource block allocated in U7 is a resource block to be suppressed, and the modulation scheme in U8 is not high-order QAM modulation (for example, when it is QPSK), U10 Proceed to set the transmission power to be suppressed at the first attenuation rate, while at U8, if the modulation method is high-order QAM modulation, proceed to U11 and strongly suppress by the second attenuation rate higher than the first attenuation rate. It is also possible to employ a setting method.

In addition, in addition to the case where only the lowest frequency resource block EB in FIG. 12 is used as the suppression target resource block, a plurality of mutually adjacent (for example, 2 or more and 6 or less) including the lowest frequency resource block EB in the first channel (CH1) It is also possible to define a series of resource blocks using some subcarriers of , as resource blocks to be suppressed, or to define all resource blocks in the first channel (CH1) as resource blocks to be suppressed.

1 portable base station device 2 MME
3 EPC function unit 4 Radio base station unit 5 UE (terminal device)
6 S-GW
7 P-GW
8 router 21 secondary battery module 22 power supply circuit unit 23 portable housing 50 wireless communication system 57 wireless bearer 301 CPU
302 RAMs
303 Mask ROM
305 Flash memory 305a Communication firmware 305b MME entity 305c S-GW entity 305d P-GW entity 306 Bus 401 CPU
402 RAMs
403 Mask ROM
404 communication interface 405 flash memory 405a communication firmware 406 bus 412 wireless communication unit 551 variable attenuator (transmission power control unit)
552 band pass filter

Claims (8)

a radio front-end circuit having a transmitting/receiving antenna, a transmitting front-end unit and a receiving front-end unit that are switchably connected to the transmitting/receiving antenna via an antenna switch; A mobile terminal device comprising a modulation/demodulation circuit for modulating a transmission wave to a station and demodulating a reception wave from the radio base station,
A public broadband mobile communication system in which a second frequency band from 172.5 MHz to 202.5 MHz adjacent to the upper limit frequency side is allocated to the first frequency band from 160 MHz to 170 MHz allocated for communication radio for broadcasting business. a power amplifier that is used in the transmission front end unit and that amplifies a transmission modulated waveform signal from the modulation/demodulation circuit and outputs the signal to the transmission/reception antenna;
The frequency information of the resource block used for packet transmission is specified based on the resource block configuration information received from the radio base station, and the resource block specifies the lower limit frequency of the second frequency band in the second frequency band. When the resource block to be suppressed uses a frequency belonging to a predetermined suppression target frequency range that includes and is lower than the upper limit frequency, the transmission power of the power amplifier is set higher than the transmission power of the resource block not to be suppressed a transmission power control unit that controls to reduce
A mobile terminal device comprising: The modulation/demodulation circuit selects one of a plurality of modulation schemes, including a high-order quadrature amplitude modulation scheme and a quadrature phase modulation scheme having a lower modulation order than the high-order quadrature amplitude modulation scheme, to modulate the transmission wave. and the transmission power control unit controls the transmission power of the power amplifier to be exempt from suppression only when the modulation scheme of the suppression target resource block is the high-order quadrature amplitude modulation scheme. 2. The mobile terminal apparatus according to claim 1, wherein control is performed so as to make it smaller than when transmitting using resource blocks of . The resource block setting information received from the radio base station includes transmission power setting information of the suppression target resource block together with frequency information of the suppression target resource block, and the transmission power control unit refers to the transmission power setting information. 3. The mobile terminal apparatus according to claim 1, wherein the transmission power of the suppression target resource block is set by Six channels with a bandwidth of 5 MHz are set in the second frequency band so as to cover the entire second frequency band. 1. Among resource blocks set in the frequency band of the first channel as one channel, the lowest frequency resource block whose block lower limit frequency matches the channel lower limit frequency is determined as the suppression target resource block. A mobile terminal device according to claim 3 . A variable attenuator is provided on the input side of the power amplifier,
The transmission power control unit sets the attenuation factor of the variable attenuator to a minimum value during transmission using the resource blocks not subject to suppression, while setting the output level of the power amplifier during transmission using the resource blocks subject to suppression. 5. The mobile terminal apparatus according to any one of claims 1 to 4, wherein the attenuation factor of said variable attenuator is adjusted so that the attenuator is attenuated by 1 dB or more. The reception front end unit is configured as a bandpass filter that includes the second frequency band in the passband, and uses a frequency band from 160 MHz to 170 MHz adjacent to the lower limit frequency side of the second frequency band. 5. The mobile terminal device according to any one of claims 1 to 4, further comprising a low-band side interference wave blocking filter for blocking a communication wave of a communication radio as a low-band side interference wave. A radio base configured to be connectable to a mobile terminal device via a terminal radio bearer, and having a resource block setting unit for setting a resource block used for packet transmission from the mobile terminal device on the terminal radio bearer. a station,
A public broadband mobile communication system in which a second frequency band from 172.5 MHz to 202.5 MHz adjacent to the upper limit frequency side is allocated to the first frequency band from 160 MHz to 170 MHz allocated for contact radio for broadcasting business. Further, the resource block setting unit includes: a resource block setting information creating unit that creates resource block setting information including frequency information and transmission power information of resource blocks used for packet transmission; A resource block setting information transmission unit that transmits to the mobile terminal device,
The resource block information creation unit uses a frequency belonging to a predetermined suppression target frequency range that includes the lower limit frequency of the second frequency band and is lower than the upper limit frequency in the second frequency band. a resource block to be suppressed, the transmission power information is generated so that the transmission power is smaller than that of a resource block not to be suppressed. a radio front-end circuit having a transmitting/receiving antenna, a transmitting front-end unit and a receiving front-end unit that are switchably connected to the transmitting/receiving antenna via an antenna switch; a mobile terminal device having a modulation/demodulation circuit for modulating a transmission wave to a station and demodulating a reception wave from the radio base station; and the mobile terminal device being connectable via a terminal radio bearer, A radio network system comprising a radio base station having a resource block setting unit for setting resource blocks used for packet transmission from the mobile terminal device on the terminal radio bearer,
A public broadband mobile communication system in which a second frequency band from 172.5 MHz to 202.5 MHz adjacent to the upper limit frequency side is allocated to the first frequency band from 160 MHz to 170 MHz allocated for communication radio for broadcasting business. Further, the resource block setting unit includes: a resource block setting information creating unit that creates resource block setting information including frequency information and transmission power information of resource blocks used for packet transmission; A resource block setting information transmission unit that transmits to the mobile terminal device,
The resource block information creating unit of the radio base station determines, in the second frequency band, the resource block to be used is a predetermined suppression target frequency range that includes the lower limit frequency of the second frequency band and is lower than the upper limit frequency. When the resource block to be suppressed uses a frequency belonging to, the transmission power information is created so that the transmission power is smaller than the resource block not to be suppressed,
The mobile terminal device includes a power amplifier that is provided in the transmission front end unit and that amplifies a transmission modulated waveform signal from the modulation/demodulation circuit and outputs the signal to the transmission/reception antenna, and a resource block that is received from the radio base station. Based on the configuration information, the frequency and transmission power of the resource block used for packet transmission are specified, and the resource block includes the lower limit frequency of the second frequency band and is higher than the upper limit frequency in the second frequency band. When the resource block to be suppressed uses a frequency belonging to a predetermined low frequency range to be suppressed, the transmission power of the power amplifier is controlled so as to be lower than that at the time of transmission using resource blocks not to be suppressed. A wireless network system, comprising: a transmission power control unit.

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