JP5051269B2 - Mobile communication terminal, mobile communication system, base station, and communication method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To avoid a burden on a mobile communication terminal caused by setting transmission timings and conveying frequencies of down-ink quality information and of an uplink pilot signal between these signals, regardless of each other, in a mobile communication system where the mobile communication terminal transmits to a base station the downlink quality information indicative of downlink channel quality and the uplink pilot signal to be used for measuring the uplink channel quality. <P>SOLUTION: A transmission timing of downlink quality information from a mobile communication terminal UE to a base station BS is synchronized with a transmission timing of an uplink pilot signal. Alternatively, the downlink quality information and the uplink pilot signal are transmitted in the same conveying frequency, or in mutually adjacent carrier frequencies among a plurality of carrier frequencies assigned to the mobile communication terminal UE, beforehand. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a mobile communication terminal, a mobile communication system, a base station, and a communication method used by them, and more particularly to a technique for controlling transmission timing of control information exchanged between a mobile communication terminal and a base station. .

  FIG. 1 shows a configuration of a UMTS (Universal Mobile Telecommunications System) which is a mobile communication system standardized by 3GPP (3rd Generation Partnership Project). The radio communication system 1 includes a radio access network N1 called UTRAN (Universal Terrestrial Radio Access Network), a circuit switched core network N2 that connects the radio access network N1 and the public telephone network N3 and provides a radio exchange service, and radio access It consists of a packet-switched core network N4 that connects a network N1 and an Internet Protocol (IP) network N5 to provide a packet-switched service.

The radio access network N1 is composed of a base station BS and a radio base station controller 2 (RNC: Radio Network Controller) that controls the base station BS, and between the mobile communication terminal UE and the core networks N2 and N4. It plays the role of transferring user information such as voice and packets and allocating radio resources necessary for the communication.
The circuit-switching core network N2 is composed of a mobile switching center (MSC) 3 and a gateway mobile switching center (GMSC) 4 and is connected between terminals by circuit-switching connection. To play a role.

The packet switching core network N4 grasps the position of the mobile communication terminal UE accessing the packet switching domain, and transfers user traffic between the packet gateway node 6 and the radio access network N1, which will be described later. A packet gateway node (GGSN) that controls the connection between the mobile communication system 1 and the external IP network N5 in accordance with a connection request from a packet access control node (SGSN) 5 and a mobile communication terminal UE GPRS Support Node) 6 and performs IP connection between the mobile communication terminals UE and IP connection between the mobile communication terminal UE and the external IP network.
In addition, the wireless communication system 1 includes a home location register (HLR) that holds user subscription information, and an authentication center (AUC: Authentication Center) that manages authentication and confidential information and performs authentication processing. 8 is provided.

While the mobile communication terminal UE and the base station BS are connected, the mobile communication terminal UE is a down link, which is a downlink line through which signals are transmitted from the base station BS to the mobile communication terminal UE. Downlink quality information (link CQI) indicating the channel quality of the link and uplink for measuring the channel quality of the uplink, which is an uplink channel in which a signal is transmitted from the mobile communication terminal UE to the base station BS Pilot signal is transmitted intermittently.
The mobile communication terminal UE receives a downlink pilot signal transmitted from the base station BS via the common pilot channel and measures the channel quality of the downlink propagation path. This measurement result is transmitted to the base station BS as downlink quality information. The base station BS knows the downlink quality information, so that when the downlink traffic is generated from the base station BS to the mobile communication terminal UE, the base station BS selects the optimum transmission format (modulation method) according to the condition of the downlink propagation path. It is possible to transmit downlink traffic using an error correction method or a coding rate.

  On the other hand, the mobile communication terminal UE transmits an uplink pilot signal to the base station BS via an uplink dedicated control channel individually assigned to each terminal. The base station BS measures the channel quality of the uplink propagation path by measuring the reception state of the uplink pilot signal. The base station BS can determine the optimum transmission format (modulation method, error correction method, coding rate, etc.) according to the condition of the uplink propagation path by measuring the channel quality of the uplink propagation path. Become.

3GPP TS 25.813 (3rd Generation Partnership Project: Technical Specification Group Radio Access Network; Evolved Universal Terrestrial Radio Access (E-UTRA) and; Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Radio interface protocol aspects) V 7.0. 0 (June 2006) 3GPP TS 25.814 (3rd Generation Partnership Project: Technical Specification Group Radio Access Network Physical layer aspects for Universal Terrestrial Radio Access (UTRA);) V 7.0.0 (June 2006)

In the conventional mobile communication system, the mobile communication terminal UE has the transmission quality of the downlink quality information and the uplink pilot signal and the carrier frequency set independently of each other between the control information. Increases the power consumption of the transmitter circuit and complicates the processing, which is a burden on the mobile communication terminal UE. The reason is shown with reference to FIG.
FIG. 2 is a time chart of a conventional example of transmission form of downlink quality information and uplink pilot signal. In FIG. 2, uplink pilot signals (Pilot) are transmitted at times t1 to t2 and t6 to t7, and downlink quality information (CQI) is transmitted at times t2 to t3, t4 to t5, and t8 to t9 at timings unrelated thereto. Has been sent.

  Thus, when the downlink quality information and the uplink pilot signal are transmitted at separate timings, the transmission circuit in the mobile communication terminal UE must be driven each time. In particular, in the 3.9th generation mobile communication system (3GPP LTE) that is currently being standardized, a MAC dormant state is provided as a standby state that the mobile communication terminal UE can take in order to immediately transmit and receive data when traffic occurs. It is done. In such a MAC dormant state, data transmission / reception is not performed, but the mobile communication terminal UE intermittently transmits downlink quality information and an uplink pilot signal.

  In such a MAC dormant state, the power supply to the amplifier circuit at the output stage of the transmission circuit is stopped and the amplifier circuit is driven intermittently during a period when the downlink quality information and the uplink pilot signal are not transmitted. Consumption can be reduced. FIG. 3 shows a state transition diagram of the mobile communication terminal UE defined by the 3.9th generation mobile communication system. In FIG. 3, the LTE-active state indicates a communication state, the MAC active (MAC-Active) state included therein indicates continuous communication, and the MAC dormant state intermittently transmits and receives control information as described above. Indicates the state to be performed. Further, the LTE idle (LTE-Idle) state indicates a standby state in which control information is not transmitted and received, and the LTE detached (LTE-Detached) state indicates a state in which the mobile communication terminal UE is powered off.

  When the amplifier circuit is driven intermittently in this way, it is necessary to stabilize the output characteristics of the amplifier circuit by energizing the amplifier circuit in advance for a predetermined waiting time before the transmission signal is input. The amplifier circuit does not amplify the transmission signal during this standby time and consumes wasted power. For this reason, if the transmission timings of the downlink quality information and the uplink pilot signal are separated, the waiting time is generated each time, and wasteful power consumption increases.

  In addition, the 3.9th generation mobile communication system uses bandwidths of 1.25 MHz, 2.5 MHz, 10 MHz, 15 MHz and 20 MHz in addition to the 5 MHz bandwidth used in the current third generation mobile communication system. Is possible. FIG. 2 shows that in a mobile communication terminal UE adopting such a 3.9th generation mobile communication system, an uplink pilot signal is transmitted on a channel with a bandwidth of 20 MHz and transmitted on a channel with a downlink quality information of 5 MHz. It shows how it is done.

Here, when changing the frequency of the transmission signal, the mobile communication terminal UE increases the power efficiency by optimizing the frequency characteristic of the amplifier circuit according to the carrier frequency. The frequency characteristic of the amplifier circuit is changed by changing the bias of the active element used in the amplifier circuit, but there is a limit to the tracking speed of the characteristic change of the active element, and when the bias change amount is large, The delay of the change of the frequency characteristic of the active element with respect to the change of the bias becomes large.
For this reason, when the change in the frequency of the transmission signal is large, it is necessary to control the bias of the active element in consideration of the delay in the change in the frequency characteristic of the active element, and the processing of the transmission circuit in the mobile communication terminal UE is complicated. To do. This problem also occurs when the frequency bandwidth of the transmission signal changes greatly as shown in FIG.

In view of the above problems, the present invention provides a mobile communication system that transmits downlink quality information and an uplink pilot signal from a mobile communication terminal to a base station, and the transmission timing and carrier frequency of the downlink quality information and the uplink pilot signal are: It is an object of the present invention to reduce the burden on the mobile communication terminal caused by setting these signals independently of each other.
That is, when the mobile communication terminal intermittently transmits the downlink quality information and the uplink pilot signal, the time for energizing the amplification circuit that amplifies these signals in the mobile communication terminal is reduced, and the power consumption is reduced.
Further, when the mobile communication terminal transmits the downlink quality information and the uplink pilot signal, the carrier frequency used for transmitting the downlink quality information and the carrier frequency used for transmitting the uplink pilot signal are greatly different from each other. To prevent the processing of the transmission circuit from becoming complicated.

  In order to achieve the above object, the present invention synchronizes the transmission timing of the downlink quality information and the transmission timing of the uplink pilot signal. By synchronizing the transmission timings of these signals, it is possible to transmit the downlink quality information and the uplink pilot signal at the same time or within consecutive times. For this reason, the opportunity to energize the amplifier circuit provided in the output stage of the transmission circuit of the mobile communication terminal is reduced, the power consumption is reduced because the time that must be energized in advance prior to signal transmission is reduced, The burden on the mobile communication terminal is reduced.

  Moreover, in this invention, downlink quality information and an uplink pilot signal are transmitted on the same carrier frequency or the mutually adjacent carrier frequency among the some carrier frequencies previously allocated to the mobile communication terminal. By determining the carrier frequency in this way, the bias control amount of the amplifier circuit provided at the output stage of the transmission circuit of the mobile communication terminal can be kept small, and the processing of the transmission circuit can be prevented from becoming complicated. The burden on the mobile communication terminal is reduced.

According to the first aspect of the present invention, the downlink channel quality is measured at the mobile communication terminal, and the downlink quality information indicating the downlink channel quality obtained as a result and the uplink quality used for the uplink channel quality measurement are measured. A mobile communication terminal used in a mobile communication system in which a mobile communication terminal intermittently transmits a link pilot signal to a base station is provided.
The mobile communication terminal includes a transmission timing control unit that synchronizes the transmission timing of the downlink quality information and the transmission timing of the uplink pilot signal, and determines the transmission quality of the downlink quality information and the uplink pilot signal to be transmitted intermittently. Synchronize.
Or a mobile communication terminal is provided with the radio | wireless transmission part which transmits downlink quality information and an uplink pilot signal with the carrier frequency adjacent to each other among the same carrier frequency or the some carrier frequency allocated beforehand.

The transmission timing control unit may set one of the transmission period of the downlink quality information and the transmission period of the uplink pilot signal as an integer multiple of the other. Further, the transmission timing control unit may control the transmission timing so that the downlink quality information and the uplink pilot signal are transmitted simultaneously or successively.
In addition, the radio transmission unit transmits both the downlink quality information and the uplink pilot signal at a part of locally existing carrier frequencies among a plurality of carrier frequencies allocated in advance in a predetermined frequency band. May be. Alternatively, the wireless transmission unit may disperse both the downlink quality information and the uplink pilot signal in a predetermined frequency band among a plurality of carrier frequencies allocated in advance in the predetermined frequency band. Each may be transmitted at a carrier frequency. At this time, the wireless transmission unit may intermittently transmit the downlink quality information and the uplink pilot signal according to the transmission timing controlled by the transmission timing control unit.

According to the second aspect of the present invention, there is provided a mobile communication terminal according to the first aspect of the present invention, wherein downlink quality information and an uplink pilot signal are intermittently transmitted from the mobile communication terminal to the base station. A communication system is provided.
When the mobile communication terminal transmits an uplink pilot signal at the same time as or close to the downlink quality information, or at the same frequency or an adjacent frequency, as a reference channel used for channel estimation of the downlink quality information It is possible to use an uplink pilot signal.
Therefore, the base station used in this system may include a channel estimation unit that performs channel estimation of a channel used for transmission of downlink quality information using an uplink pilot signal received from a mobile communication terminal as a reference channel. Good.

  According to the 3rd form of this invention, the base station used for the mobile communication system by the 2nd form of this invention is provided. This base station includes a channel estimation unit that performs channel estimation of a channel used for transmission of downlink quality information using an uplink pilot signal received from a mobile communication terminal as a reference channel.

According to the fourth aspect of the present invention, the downlink channel quality is measured by the mobile communication terminal, and the downlink quality information indicating the downlink channel quality obtained as a result and the uplink channel quality measurement are used. A communication method in which a mobile communication terminal transmits a link pilot signal to a base station is provided.
In this communication method, downlink quality information and uplink pilot signals are intermittently transmitted from the mobile communication terminal to the base station, and the mobile communication terminal synchronizes the transmission timing of the downlink quality information and the transmission timing of the uplink pilot signal. Let Alternatively, the mobile communication terminal transmits the downlink quality information and the uplink pilot signal at the same carrier frequency or a carrier frequency adjacent to each other among a plurality of pre-assigned carrier frequencies.

When synchronizing the transmission timing of the downlink quality information and the transmission timing of the uplink pilot signal, one of the transmission period of the downlink quality information and the transmission period of the uplink pilot signal may be an integer multiple of the other, Alternatively, it may be transmitted simultaneously or continuously with the downlink quality information and the uplink pilot signal.
Both the downlink quality information and the uplink pilot signal may be transmitted respectively on some locally existing carrier frequencies among a plurality of carrier frequencies allocated in advance in a predetermined frequency band. Both the quality information and the uplink pilot signal are respectively transmitted on a part of the carrier frequencies distributed in the predetermined frequency band among a plurality of carrier frequencies allocated in advance in the predetermined frequency band. Also good.
Furthermore, in this method, the base station may perform channel estimation of a channel used for transmission of downlink quality information using an uplink pilot signal received from a mobile communication terminal as a reference channel.

According to the present invention, it is possible to transmit the downlink quality information and the uplink pilot signal at the same time or within a mutually continuous time, so that an amplifier circuit provided at the output stage of the transmission circuit of the mobile communication terminal The opportunity to energize is reduced, and the time that must be energized prior to signal transmission is reduced, so that power consumption is reduced.
Also, since the carrier frequency of the downlink quality information and the uplink pilot signal can be the same or the difference between them can be reduced, the bias control amount of the amplifier circuit provided at the output stage of the transmission circuit of the mobile communication terminal can be reduced. Therefore, it is possible to prevent the transmission circuit from being complicated.

It is a block diagram of the mobile communication system standardized by 3GPP. It is a time chart of the prior art example of the transmission form of downlink quality information and an uplink pilot signal. It is a state transition diagram of the mobile communication terminal UE prescribed | regulated by the 3.9th generation mobile communication system. 1 is a schematic configuration diagram of a base station according to an embodiment of the present invention. It is a schematic block diagram of the mobile communication terminal by the Example of this invention. 6 is a flowchart showing downlink quality information and uplink pilot transmission operations by the mobile communication terminal shown in FIG. 5. It is a time chart of a downlink pilot signal and alerting | reporting information. It is a time chart (the 1) of the transmission form of the downlink quality information and uplink pilot signal by the mobile communication terminal of this invention. It is a time chart (the 2) of the transmission form of the downlink quality information and uplink pilot signal by the mobile communication terminal of this invention. (A) is a figure which shows the 1st structural example of the radio | wireless transmission part of the mobile communication terminal shown in FIG. 5, (B) is a figure which shows the 2nd structural example of a radio | wireless transmission part. It is a time chart (the 1) of the transmission form of the downlink quality information and uplink pilot signal which are transmitted by the distributed system by the mobile communication terminal of this invention. It is a time chart (the 2) of the transmission form of the downlink quality information and uplink pilot signal which are transmitted by the distributed system by the mobile communication terminal of this invention. It is a time chart (the 1) of the transmission form of the downlink quality information and uplink pilot signal transmitted by the mobile communication terminal of this invention by the localized system. It is the time chart (the 2) of the transmission form of the downlink quality information and uplink pilot signal which are transmitted by the mobile communication terminal of this invention by the localized system. It is a time chart (the 1) of the transmission form of a downlink quality information and uplink pilot signal when there is a difference in the amount of transmission data. It is a time chart (the 2) of the transmission form of a downlink quality information and uplink pilot signal when there is a difference in the amount of transmission data. It is a time chart (the 3) of the transmission form of a downlink quality information and uplink pilot signal when there is a difference in the amount of transmission data. It is a time chart (the 4) of the transmission form of a downlink quality information and uplink pilot signal when there is a difference in the amount of transmission data. (A) is a figure which shows the 1st structural example of the radio | wireless receiving part of the base station shown in FIG. 4 in the case of performing channel estimation of downlink quality information, (B) shows the 2nd structural example of a radio | wireless receiving part. FIG. 5 is a flowchart showing channel estimation operation of downlink quality information by the base station shown in FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 4 is a schematic configuration diagram of a base station according to an embodiment of the present invention, and FIG. 5 is a schematic configuration diagram of a mobile communication terminal according to an embodiment of the present invention. The mobile communication system according to the embodiment of the present invention has the same configuration as the mobile communication system described with reference to FIG. This mobile communication system supports the 3.9th generation mobile communication system, and the mobile communication terminal UE shown in FIG. 5 can take each state shown in the state transition diagram of FIG.

The base station BS shown in FIG. 4 includes a transmission antenna 101 and a radio transmission unit 102 for transmitting a downlink radio signal to the mobile communication terminal UE. On the downlink radio signal, various control information is transmitted via the downlink dedicated control channel, the downlink common control channel, and the common pilot channel.
The downlink dedicated control channel is an individual control channel assigned to each mobile communication terminal UE in order to transmit control information from the base station BS to the mobile communication terminal UE, and the downlink common control channel is all transmitted from the base station BS. The control channel transmits control information to the mobile communication terminal UE simultaneously, and the common pilot channel is a control channel that transmits a downlink pilot signal simultaneously from the base station BS to all mobile communication terminals UE.
The base station BS transmits the downlink pilot signal via the common pilot channel and the downlink dedicated control channel processing unit 103 and the downlink common control channel 104 that perform signal transmission processing through the downlink dedicated control channel and the downlink common control channel, respectively. And a common pilot channel processing unit 105 for transmission.

The base station BS also includes a reception antenna 111 and a radio reception unit 112 for receiving an uplink radio signal from the mobile communication terminal UE. On the uplink radio signal, various control information is transmitted via the first and second uplink control channels.
The first and second uplink control channels are control channels that can individually transmit control information from each mobile communication terminal UE. Such a control channel may be a shared control channel that assigns common physical channel resources to different mobile communication terminals UE by changing time slots, frequencies, and spreading codes, or is assigned to different mobile communication terminals UE, respectively. It may be a separate control channel.
The base station BS includes a first uplink control channel receiving unit 113 and a second uplink control channel receiving unit 114 that perform reception processing of control information transmitted via the first and second uplink control channels.

  Furthermore, the base station BS includes a transmission timing information generation unit 106 that generates transmission timing information that specifies transmission timing at which the mobile communication terminal UE transmits downlink quality information or an uplink pilot signal. The transmission time information generation unit 106 outputs the created transmission time information to the downlink dedicated control channel processing unit 103 and transmits it to the mobile communication terminal UE via the downlink dedicated control channel. A method for designating the transmission quality of the downlink quality information or the uplink pilot signal based on the transmission time information will be exemplified later. The transmission time information may be created not by the base station BS but by the upper radio base station controller 2 shown in FIG. In this case, the transmission time information generation unit 106 is provided not in the base station BS but in the radio base station control device 2.

  Returning to FIG. 4, the base station BS includes a broadcast information generation unit 107 that creates broadcast information. The broadcast information includes a frame number indicating which frame pilot signal the downlink pilot signal currently transmitted by the common pilot channel processing unit 105 is. The broadcast information generation unit 107 outputs the broadcast information to the downlink common control channel processing unit 104, and transmits the broadcast information to the mobile communication terminal UE via the downlink common control channel.

The mobile communication terminal UE shown in FIG. 5 includes a reception antenna 201, a radio reception unit 202 for receiving a downlink radio signal from the base station BS, and a downlink pilot signal transmitted via a common pilot channel. The common pilot channel receiving unit 203 that performs reception processing for receiving, the downlink dedicated control channel receiving unit 204 that performs reception processing of control information transmitted via the downlink dedicated control channel, and the downlink common control channel A downlink common control channel receiving unit 205 that performs reception processing of control information.
The mobile communication terminal UE also performs a signal transmission process via the transmission antenna 211, a radio transmission unit 212 for transmitting an uplink radio signal to the base station BS, and a first uplink control channel. An uplink control channel processing unit 213 and a second uplink control channel processing unit 214 that performs signal transmission processing via the second uplink control channel are provided.

The mobile communication terminal UE further includes a CQI generation unit 206, a pilot generation unit 215, a frame / slot number detection unit 207, a transmission timing detection unit 208, and a transmission timing control unit 216.
The CQI generation unit 206 measures a predetermined index value indicating the downlink channel quality such as SIR (signal-to-interference power ratio) of the common pilot channel, and generates downlink quality information including the index value to generate first quality information. The data is output to the uplink control channel processing unit 213. Downlink quality information is transmitted to the base station BS via the first uplink control channel.
The pilot generation unit 215 generates an uplink pilot signal used by the base station BS to measure uplink channel quality, and outputs the uplink pilot signal to the second uplink control channel processing unit 214. The uplink pilot signal is transmitted to the base station BS via the second uplink control channel.

  The frame / slot number detection unit 207 detects the current downlink pilot frame number included in the broadcast information received by the downlink common control channel reception unit 205. Further, the frame / slot number detection unit 207 determines the slot number of the current time slot by measuring the elapsed time from the time when the common pilot channel reception unit 203 starts to receive the downlink pilot of the current frame to the present. To detect.

The transmission time detection unit 208 detects transmission time information from the control information transmitted through the downlink dedicated control channel and received by the downlink dedicated control channel reception unit 204.
The transmission time control unit 216 inputs transmission time information from the transmission time detection unit 208 and inputs the frame number and slot number of the current time slot from the frame / slot number detection unit 207. The transmission time detection unit 208 determines whether the current time slot is a slot for transmitting a signal with respect to each of the downlink quality information and the uplink pilot on the basis of the transmission time information input from the transmission time detection unit 208. Determine whether or not.

  Each time the transmission timing control unit 216 determines that the current time slot is a slot for transmitting the downlink quality information, the transmission permission signal that permits the first uplink control channel processing unit 213 to transmit the downlink quality information. , And a transmission permission signal for permitting transmission of the uplink pilot is output to the second uplink control channel processing unit 214 every time it is determined that the current time slot is a slot for transmitting the uplink pilot. By this operation, the transmission timing detection unit 208 synchronizes the transmission timing of the downlink quality information and the transmission timing of the uplink pilot, and transmits these signals intermittently.

FIG. 6 is a flowchart showing downlink quality information and uplink pilot transmission operations by the mobile communication terminal UE shown in FIG.
In step S1, the downlink dedicated control channel receiving unit 204 uses the downlink dedicated control to transmit the downlink quality information generated by the transmission timing information generating unit 106 of the base station BS or the transmission timing information specifying the transmission timing of the uplink pilot signal. Receive via channel. The transmission time detection unit 208 detects transmission time information specified for the mobile communication terminal UE from the signal on the downlink dedicated control channel received by the downlink dedicated control channel reception unit 204.
The transmission timing information is used as a reference when the transmission timing control unit 216 determines when to output the downlink quality information and the uplink pilot signal transmission permission signal to the first and second uplink control channel processing units 213 and 214, respectively. Information. The transmission time information may be, for example, a frame number and a slot number that specify a time slot for transmitting one or both of the downlink quality information and the uplink pilot signal.

  Also, for example, when the transmission cycle of the downlink quality information and the transmission cycle of the uplink pilot signal are determined in advance, the frame number including the time slot assigned as the transmission time to this mobile communication terminal UE is set as the transmission cycle. It may be specified by the corresponding frame number n and a remainder obtained by dividing the frame number by this frame number n.

In step S2, when the common pilot channel receiving unit 203 receives the downlink pilot signal, the CQI generating unit 206 generates downlink quality information. Common pilot channel receiving section 203 also outputs a downlink pilot signal to frame / slot number detecting section 207.
In step S3, the downlink common channel detection unit 205 receives the broadcast information generated by the broadcast information generation unit 107 of the base station BS via the downlink common control channel.

In step S4, the frame / slot number detector 207 detects the frame number of the currently transmitted downlink pilot signal from the broadcast information. The frame / slot number detection unit 207 detects the slot number of the current time slot.
FIG. 7 is a time chart of a downlink pilot signal and broadcast information. The downlink pilot signal flowing in the common pilot channel repeats a known bit pattern for each frame. The broadcast information includes the frame number of the currently transmitted downlink pilot signal. Since the bit pattern of the downlink pilot signal is known, the frame / slot number detection unit 207 determines the start time of the frame by collating the received downlink pilot signal with the previously known bit pattern. It is possible.
As shown in the figure, one frame is composed of a predetermined number of slots (m in the example shown) having a known time width. The frame / slot number detection unit 207 can determine the slot number of the current time slot by knowing the elapsed time from the start time of the current frame.

Returning to FIG. 6, in step S5, the transmission timing control unit 216 determines that the current time slot in which the frame number and slot number are detected in step S4 is the transmission timing information detected in step S1 is the uplink pilot signal. It is determined whether or not it is the designated transmission time.
At this time, for example, when the transmission time information indicates the frame number and slot number of the time slot in which the uplink pilot signal is to be transmitted, the transmission time control unit 216 sets the frame number and slot number of the instructed time slot. It is determined whether the combination matches the frame number and slot number combination of the current time slot. If these combinations match, it is determined that it is the transmission time, and if these combinations do not match Is determined not to be the transmission time.

Also, for example, when the transmission time information indicates only the frame number and slot number of the time slot in which the downlink quality information is to be transmitted, the transmission time control unit 216 combines the frame number and slot number of the current time slot. Determines whether the combination of the frame number and slot number of the designated time slot satisfies the predetermined relationship, and determines that it is the transmission time when these combinations satisfy the predetermined relationship, If the combination does not satisfy the predetermined relationship, it is determined that it is not the transmission time.
The predetermined relationship includes, for example, a combination of a frame number and a slot number that is the same, or a time slot that transmits an uplink pilot signal precedes a time slot that transmits downlink quality information by a predetermined number of slots, or Various relationships such as being late may be adopted.
Alternatively, the transmission timing control unit 216 may use the uplink pilot signal for the downlink quality information transmitted in the designated time slot based on the time required for transmitting the downlink quality information and the time required for transmitting the uplink pilot signal. May be determined so that the uplink pilot signal is transmitted continuously.

  If it is determined in step S5 that it is the transmission time of the uplink pilot signal, the transmission time control unit 216 outputs a transmission permission signal that permits transmission of the uplink pilot to the second uplink control channel processing unit 214 in step S6. . If the transmission time control unit 216 determines that it is not the transmission time of the uplink pilot signal in step S5, the process proceeds to step S7.

In step S7, the transmission time control unit 216 determines that the current time slot in which the frame number and slot number are detected in step S4 is the transmission time specified by the transmission time information detected in step S1 for the downlink quality information. It is determined whether or not there is.
At this time, for example, when the transmission time information indicates the frame number and slot number of the time slot in which the downlink quality information is to be transmitted, the transmission time control unit 216 sets the frame number and slot number of the instructed time slot. It is determined whether the combination matches the frame number and slot number combination of the current time slot. If these combinations match, it is determined that it is the transmission time, and if these combinations do not match Is determined not to be the transmission time.

  Further, for example, when the transmission timing information indicates only the frame number and slot number of the time slot in which the uplink pilot signal is to be transmitted, the transmission timing control unit 216 combines the frame number and slot number of the current time slot. Determines whether or not the combination of the frame number and slot number of the instructed time slot satisfies the above-described predetermined relationship, and determines that it is the transmission time when these combinations satisfy the predetermined relationship, When these combinations do not satisfy the predetermined relationship, it is determined that it is not the transmission time.

Alternatively, the transmission timing control unit 216 performs the downlink quality on the uplink pilot signal transmitted in the designated time slot based on the time required for transmitting the downlink quality information and the time required for transmitting the uplink pilot signal. The transmission timing of the downlink quality information may be determined so that the information is continuously transmitted.
If it is determined in step S7 that it is the transmission timing of the downlink quality information, the transmission timing control unit 216 outputs a transmission permission signal that permits transmission of the downlink quality information to the first uplink control channel processing unit 213 in step S8. To do.

  By operating according to the flowchart shown in FIG. 6, the mobile communication terminal UE can synchronize the transmission timing of the downlink quality information and the transmission timing of the uplink pilot signal. For example, when the period required for transmission of the uplink pilot signal (Pilot) and the period required for transmission of the downlink quality information (CQI) are known, the transmission timing control unit 216 increases the time as shown in FIG. The transmission timing t2 of the downlink quality information and the transmission timing t1 of the uplink pilot signal are synchronized so that the transmission periods t1 to t2 of the link pilot signal and the transmission periods t2 to t3 of the downlink quality information are continuous.

In the example of FIG. 8, uplink pilot signals are transmitted at times t1 to t2 and times t4 to t5, and downlink quality information is transmitted at the same frequency band as the uplink pilot signals at times t2 to t3 and times t5 to t6. In this case, signal transmission from the mobile communication terminal UE is stopped at times t3 to t4, and the transmission cycle of the uplink pilot signal and the downlink quality information is the same.
In the example of FIG. 8, in order to transmit the uplink pilot signal and the downlink quality information in the same frequency band, the radio transmission unit 212 transmits a first uplink control channel and a second uplink control channel that respectively transmit them. Uplink control channels using different times or spreading codes in the same frequency band may be allocated, and the first uplink control channel and the second uplink control channel may be the same uplink control channel.

Next, in the example of the transmission timing of the downlink quality information and the uplink pilot signal shown in FIG. 9, the transmission timing control unit 216 has the same transmission period of the uplink pilot signal and the transmission period of the downlink quality information. As described above, the transmission timing of the downlink quality information and the transmission timing of the uplink pilot signal are synchronized.
In the example of FIG. 9, both the downlink quality information and the uplink pilot signal are transmitted from time t1 to t2 and from time t3 to t4, and the signal transmission from the mobile communication terminal UE is stopped from time t2 to t3. And the case where the transmission period of an uplink pilot signal and downlink quality information is the same is shown.

  In the example of FIG. 9, the radio transmission unit 212 transmits the uplink pilot signal and the downlink quality information in different frequency bands. In order to avoid the processing of the wireless transmission unit 212 from being complicated as described above due to a large difference in the transmission frequency of these control information, the wireless transmission unit 212 includes several assigned to the mobile communication terminal UE. Of the carrier frequencies, adjacent carrier frequencies are allocated for transmission of uplink pilot signals and downlink quality information.

  As the wireless transmission unit 212, for example, a multicarrier transmission circuit that transmits transmission signals in parallel on a plurality of carrier frequencies, such as an Orthogonal Frequency Division Multiplexing (OFDM) transmission device, may be employed. And the radio transmission part 212 may transmit either one or both of an uplink pilot signal and downlink quality information in parallel on a plurality of carrier frequencies. FIGS. 10A and 10B are diagrams illustrating a configuration example of the wireless transmission unit 212 configured as an OFDM transmission circuit.

  As shown in FIG. 10A and FIG. 10B, the wireless transmission unit 212 transmits the uplink pilot signal and the downlink quality output from the first and second uplink control channel processing units 213 and 214, respectively. Serial parallel conversion circuits 230 and 231 that convert information into parallel signals, an inverse Fourier transform circuit 234 that performs inverse Fourier transform processing on the parallel signals converted by the serial parallel conversion circuits 230 and 231, and an inverse Fourier transform circuit 234 Digital analog-to-analog conversion circuits 235 and 236 that convert the digital quadrature signal output from the analog quadrature signal, a quadrature modulator (QMOD) 237 that performs quadrature modulation on the analog quadrature signal, and a radio signal that transmits the quadrature-modulated transmission signal And a frequency conversion circuit 238 for conversion into In the configuration diagrams of FIG. 10 (A) and FIG. 10 (B), only the parts necessary for transmitting the uplink pilot signal and the downlink quality information are shown for the sake of simplicity. The unit 212 includes components necessary for transmitting other control signals, packet data, and audio data.

  The radio transmission unit 212 illustrated in FIG. 10A performs the first uplink control channel transmission timing according to the transmission permission signals of the first and second uplink control channels output from the transmission timing processing unit 216. The output signal of the serial / parallel conversion circuit 230 that converts the input signal from the control channel processing unit 213 into a parallel signal, and the input signal from the second uplink control channel 214 processing unit at the transmission timing of the second uplink control channel are parallel signals. A switch 239 is provided for inputting the output signal of the serial / parallel conversion circuit 231 for conversion into the same input terminal of the inverse Fourier transform circuit 234. Accordingly, the inverse Fourier transform circuit 234 assigns the same frequency band to the first and second uplink control channels, whereby the uplink pilot signal and the downlink quality information are transmitted using the carrier of the same frequency.

  FIG. 11 is a time chart of a transmission form of the downlink quality information and the uplink pilot signal transmitted by the wireless transmission unit 212 illustrated in FIG. As shown, the uplink pilot signal is divided on a plurality of carrier frequencies and transmitted in parallel, and the downlink quality information is also divided on the plurality of carrier frequencies and transmitted in parallel. Also, the transmission timings t1 and t2 of these control information are synchronized so that the transmission periods t1 to t2 for transmitting the uplink pilot signal and the transmission periods t2 to t3 for transmitting the downlink quality information are continuous. The link pilot signal and the downlink quality information are transmitted in the same period using a carrier wave having the same frequency.

  Further, in the transmission form shown in FIG. 11, in order to reduce the influence on the entire signal even if noise occurs in some frequency bands, the downlink quality information and the uplink pilot signal are used in a so-called distributed system. Send. That is, the inverse Fourier transform circuit 234 determines a part of the carrier frequencies distributed in the predetermined frequency band among the plurality of carrier frequencies existing in the predetermined frequency band assigned to the mobile communication terminal UE. Assign for transmission of downlink quality information and uplink pilot signal.

  In the wireless transmission unit 212 illustrated in FIG. 10B, the output signal of the serial / parallel conversion circuit 230 and the output signal of the serial / parallel conversion circuit 231 are input to different input terminals of the inverse Fourier transform circuit 234. For this purpose, the uplink pilot signal and the downlink quality information are transmitted using carrier waves of different frequencies, and the control information can be transmitted simultaneously as described with reference to FIG.

  FIG. 12 is a time chart of a transmission form of the downlink quality information and the uplink pilot signal transmitted by the wireless transmission unit 212 illustrated in FIG. As shown, the uplink pilot signal is divided on a plurality of carrier frequencies and transmitted in parallel, and the downlink quality information is also divided on the plurality of carrier frequencies and transmitted in parallel. The uplink pilot signal and the downlink quality information are transmitted at the same transmission time. Furthermore, the uplink pilot signal and the downlink quality information are transmitted using different frequency carriers.

Also, the downlink quality information and the uplink pilot signal can be transmitted by the above-described distributed scheme in the transmission form shown in FIG. Here, in the distributed system, even if the band of each carrier wave is narrow, since these carrier waves are widely dispersed, the frequency bandwidth used for the entire signal is wide. For this reason, if the downlink quality information and the uplink pilot signal are transmitted in different frequency bands, the transmission frequencies of these control information are greatly different, which complicates the processing of the radio transmission unit 212 as described above. There is a fear.
In order to avoid that the carrier frequencies of the downlink quality information and the uplink pilot signal differ greatly, in the transmission form shown in FIG. 12, the inverse Fourier transform circuit 234 has several carrier frequencies assigned to the mobile communication terminal UE. Of these, carrier frequencies adjacent to each other are allocated for transmission of uplink pilot signals and downlink quality information, and it is avoided that the transmission frequencies used for these transmissions differ greatly.

  Downlink quality information and uplink pilot signals may be transmitted in a so-called localized manner. That is, the inverse Fourier transform circuit 234 determines a part of carrier frequencies that are locally present in the predetermined frequency band among the plurality of carrier frequencies that are present in the predetermined frequency band assigned to the mobile communication terminal UE. May be allocated for transmission of downlink quality information and uplink pilot signals. 13 and 14 are time charts showing an example of a transmission form in which downlink quality information and an uplink pilot signal are transmitted in a localized manner.

In the example of FIG. 13, the uplink pilot signal at times t1 to t2 and t4 to t5, and the downlink quality information at times t2 to t3 and t5 to t6 are within the frequency band allocated to the mobile communication terminal UE. Are transmitted using a part of the carrier frequencies that are present locally, and the uplink pilot signal and the downlink quality information are transmitted using the same frequency carrier wave in the same transmission period. Shows the case.
In the example of FIG. 14, at time t1 to t2 and time t3 to t4, the uplink pilot signal and the downlink quality information are localized among the plurality of carrier frequencies existing in the frequency band allocated to the mobile communication terminal UE. 9 are used in the same manner as shown in FIG. 9, in which carrier waves that are transmitted at the same time and carry the uplink pilot signal and the downlink quality information are adjacent to each other in the same manner as shown in FIG. Show.

The transmission timing control unit 216 may set one of the transmission period of the uplink pilot signal and the transmission period of the downlink quality information as an integer multiple of the other, and vary the transmission frequency of these control information. For example, in the example of the transmission form shown in FIG. 15, the transmission period of the uplink pilot signal is twice the transmission period of the downlink quality information. In the example of the transmission form shown in FIG. 16, the transmission period of the downlink quality information is The transmission period of the uplink pilot signal is twice.
As a result, for example, the amount of uplink pilot signal and downlink quality information transmitted within a certain period of time is different, or the ratio of frequency bandwidth used for transmission of uplink pilot signal and downlink quality information is freely set. It becomes possible to do.

  Further, the radio transmission unit 212 varies the amount of information of the uplink pilot signal and the downlink quality information transmitted within a certain period by differentiating the frequency bandwidth used for transmission of the uplink pilot signal and the downlink quality information. You can squeeze it. In the example of the transmission form shown in FIG. 17, a frequency bandwidth Δfc larger than the frequency bandwidth Δfp used for transmission of the uplink pilot signal is used for transmission of the downlink quality information. In the example, a frequency bandwidth Δfc that is smaller than the frequency bandwidth Δfp used for transmission of the uplink pilot signal is used for transmission of downlink quality information.

By transmitting the downlink quality information and the uplink pilot signal at the same or near time and at the same frequency or an adjacent frequency by the mobile communication terminal UE described above, the radio reception unit 112 of the base station BS shown in FIG. The uplink pilot signal can be used as a reference channel for channel estimation of downlink quality information.
FIGS. 19A and 19B are diagrams illustrating a configuration example of the radio reception unit 112 in FIG. 4. These radio reception units 112 use the uplink pilot signal as a reference channel and are down-coded. A channel estimation unit 136 that performs channel estimation of link quality information is provided.

For example, when the radio transmitter 212 of the mobile communication terminal UE is an OFDM transmitter as shown in FIGS. 10A and 10B, the radio receiver 112 of the base station BS An OFDM receiver as shown in (A) and (B) of FIG. 19 is obtained.
The radio receiving unit 112 converts a radio frequency reception signal received from the antenna 121 into an intermediate frequency signal, a quadrature detection circuit 132 that performs quadrature detection on the intermediate frequency signal, and an analog output from the quadrature detection circuit 132. Analog-to-digital conversion circuits 133 and 134 for converting the orthogonal signal into a digital orthogonal signal, a Fourier transform circuit (FFT) 135 for demodulating downlink quality information and an uplink pilot signal from the digital orthogonal signal, and demodulated downlink quality information And parallel-serial conversion circuits 138 and 139 that convert the uplink pilot signal into a serial signal and output the serial signal to the first and second control channel receivers 113 and 114, respectively.
In the configuration diagrams shown in FIGS. 19A and 19B, only the portions necessary for receiving the uplink pilot signal and the downlink quality information are shown. Reference numeral 112 includes components necessary for receiving other control signals, packet data, and voice data.

  The radio reception unit 112 uses the uplink pilot signal output from the Fourier transform circuit 135 as a reference channel, and outputs a correction signal that compensates for the variation generated in the transmission path through which the uplink pilot signal is transmitted. A channel estimation unit 136; and a multiplication circuit 137 that multiplies the correction signal output from the channel estimation unit 136 by the downlink quality information output from the Fourier transform circuit 135.

  FIG. 19A shows a configuration of radio reception section 112 when the uplink pilot signal and the downlink quality information are transmitted using carrier waves of different frequencies. In this configuration, the uplink pilot signal and the downlink quality information are respectively output from different terminals of the Fourier transform circuit 135, the parallel / serial conversion circuit 138 is connected to a terminal for outputting the downlink quality information, and the parallel / serial conversion circuit 139 It is connected to a terminal that outputs an uplink pilot signal. As a result, the downlink quality information is output to the first uplink control channel receiver 113, and the uplink pilot signal is output to the second uplink control channel receiver 114.

FIG. 19B shows a configuration of radio reception section 112 when the uplink pilot signal and the downlink quality information are transmitted using a carrier wave having the same frequency. In this configuration, the uplink pilot signal and the downlink quality information are output from the same terminal of the Fourier transform circuit 135, respectively. For this reason, the output signal from the Fourier transform circuit 135 is output to the parallel-serial conversion circuit 138 at the reception time of the downlink quality information, and the output signal from the Fourier transform circuit 135 is output at the reception time of the uplink pilot signal. A switch 140 for outputting to the parallel-serial conversion circuit 139 is provided.
The transmission time information generation unit 106 determines the reception time of the uplink pilot signal and the downlink quality information according to the transmission time information created for transmission to the mobile communication terminal UE. Then, a switching control signal for causing the switch 140 to execute the switching operation is generated.
The switch 140 distributes the output signal from the Fourier transform circuit 135 to the parallel serial conversion circuits 138 and 139 in accordance with the switching control signal, outputs the downlink quality information to the first uplink control channel receiving unit 113, and the uplink pilot signal. Is output to the second uplink control channel receiver 114.

  Channel estimation section 136 uses the signal output from Fourier transform circuit 135 at the reception timing of the uplink pilot signal as a reference channel according to the switching control signal output from transmission timing information generation section 106, and transmits the uplink pilot signal. By generating a correction signal that compensates for fluctuations generated in the transmission path, and multiplying the output signal of the Fourier transform circuit 135 by this correction signal using the multiplication circuit 137 at the reception time of the downlink quality information, the downlink Correct quality information.

FIG. 20 is a flowchart showing channel estimation operation of downlink quality information by the base station BS.
In step S11, the radio reception unit 112 receives an uplink pilot signal transmitted from the mobile communication terminal UE via the second uplink control channel, and at the same time, at a carrier frequency adjacent to the carrier frequency of the uplink pilot signal. Received downlink quality information on the transmitted first uplink control channel. Alternatively, the radio reception unit 112 receives an uplink pilot signal transmitted from the mobile communication terminal UE via the second uplink control channel, and a carrier that is the same as or adjacent to the carrier frequency of the uplink pilot signal at a time close thereto. Downlink quality information on the first uplink control channel transmitted at the frequency is received.

In step S12, the channel estimation unit 136 performs channel estimation of the first uplink control channel using the uplink pilot signal output from the Fourier transform circuit 135 as a reference channel, and generates a correction signal for downlink quality information. To do.
In step S <b> 13, the channel estimation unit 136 corrects the downlink quality information by multiplying the downlink quality information output from the Fourier transform circuit 135 by using the multiplication circuit 137.

  Although the present invention has been described in detail with reference to the preferred embodiments, specific embodiments of the present invention will be added below for easy understanding of the present invention.

(Appendix 1)
The downlink channel quality is measured, and the resulting downlink quality information indicating the downlink channel quality and the uplink pilot signal used for the uplink channel quality measurement are intermittently transmitted to the base station. A mobile communication terminal,
A mobile communication terminal comprising: a transmission timing control unit that synchronizes the transmission timing of the downlink quality information and the transmission timing of the uplink pilot signal.

(Appendix 2)
The mobile communication terminal according to supplementary note 1, wherein the transmission timing control unit sets one of the transmission period of the downlink quality information and the transmission period of the uplink pilot signal as an integer multiple of the other.

(Appendix 3)
The mobile communication terminal according to supplementary note 1, wherein the transmission time control unit controls the transmission time so that the downlink quality information and the uplink pilot signal are transmitted simultaneously or successively.

(Appendix 4)
A radio transmission unit that transmits the downlink quality information and the uplink pilot signal according to the transmission time controlled by the transmission time control unit,
The radio transmission unit may receive both the downlink quality information and the uplink pilot signal at a part of locally existing carrier frequencies among a plurality of carrier frequencies allocated in advance in a predetermined frequency band. The mobile communication terminal according to any one of Supplementary notes 1 to 3, wherein the mobile communication terminal transmits the mobile communication terminal.

(Appendix 5)
A radio transmission unit that transmits the downlink quality information and the uplink pilot signal according to the transmission time controlled by the transmission time control unit,
The radio transmission unit exists by distributing both the downlink quality information and the uplink pilot signal in the predetermined frequency band among a plurality of carrier frequencies allocated in advance in the predetermined frequency band. The mobile communication terminal according to any one of appendices 1 to 3, wherein the mobile communication terminal transmits each of them at a part of the carrier frequency.

(Appendix 6)
A mobile communication terminal that measures downlink channel quality and transmits the downlink quality information indicating the downlink channel quality obtained as a result thereof and an uplink pilot signal used for uplink channel quality measurement to a base station Because
A mobile communication terminal comprising: a radio transmission unit configured to transmit the downlink quality information and the uplink pilot signal at the same carrier frequency or a carrier frequency adjacent to each other among a plurality of pre-assigned carrier frequencies. .

(Appendix 7)
The radio transmission unit may receive both the downlink quality information and the uplink pilot signal at a part of locally existing carrier frequencies among a plurality of carrier frequencies allocated in advance in a predetermined frequency band. The mobile communication terminal according to appendix 6, wherein transmission is performed.

(Appendix 8)
The radio transmission unit exists by distributing both the downlink quality information and the uplink pilot signal in the predetermined frequency band among a plurality of carrier frequencies allocated in advance in the predetermined frequency band. The mobile communication terminal according to appendix 6, wherein the mobile communication terminal transmits each of them at a part of the carrier frequency.

(Appendix 9)
Downlink channel quality is measured, and downlink quality information indicating the downlink channel quality obtained as a result and an uplink pilot signal used for uplink channel quality measurement are intermittently transmitted to the base station. A mobile communication system,
The mobile communication terminal includes a transmission timing control unit that synchronizes the transmission timing of the downlink quality information and the transmission timing of the uplink pilot signal.

(Appendix 10)
The mobile communication system according to appendix 9, wherein the transmission timing control unit sets one of the transmission period of the downlink quality information and the transmission period of the uplink pilot signal as an integer multiple of the other.

(Appendix 11)
The mobile communication system according to appendix 9, wherein the transmission timing control unit controls the transmission timing so that the downlink quality information and the uplink pilot signal are transmitted simultaneously or successively.

(Appendix 12)
The mobile communication terminal includes a radio transmission unit that transmits the downlink quality information and the uplink pilot signal according to a transmission timing controlled by the transmission timing control unit,
The radio transmission unit may receive both the downlink quality information and the uplink pilot signal at a part of locally existing carrier frequencies among a plurality of carrier frequencies allocated in advance in a predetermined frequency band. The mobile communication system according to any one of appendices 9 to 11, wherein transmission is performed.
(Appendix 13)
The mobile communication terminal includes a radio transmission unit that transmits the downlink quality information and the uplink pilot signal according to a transmission timing controlled by the transmission timing control unit,
The radio transmission unit exists by distributing both the downlink quality information and the uplink pilot signal in the predetermined frequency band among a plurality of carrier frequencies allocated in advance in the predetermined frequency band. The mobile communication system according to any one of appendices 9 to 11, wherein transmission is performed at each of some carrier frequencies.

(Appendix 14)
Mobile communication in which downlink channel quality is measured, and downlink quality information indicating the downlink channel quality obtained as a result and an uplink pilot signal used for uplink channel quality measurement are transmitted to a base station A system,
The mobile communication terminal includes a radio transmission unit that transmits the downlink quality information and the uplink pilot signal at the same carrier frequency or a carrier frequency adjacent to each other among a plurality of pre-assigned carrier frequencies. A mobile communication system.

(Appendix 15)
The radio transmission unit may receive both the downlink quality information and the uplink pilot signal at a part of locally existing carrier frequencies among a plurality of carrier frequencies allocated in advance in a predetermined frequency band. 15. The mobile communication system according to appendix 14, wherein transmission is performed.

(Appendix 16)
The radio transmission unit exists by distributing both the downlink quality information and the uplink pilot signal in the predetermined frequency band among a plurality of carrier frequencies allocated in advance in the predetermined frequency band. 15. The mobile communication system according to supplementary note 14, wherein each of the carrier communication frequencies is transmitted.

(Appendix 17)
The base station comprises a channel estimation unit that performs channel estimation of a channel used for transmission of the downlink quality information using the uplink pilot signal received from the mobile communication terminal as a reference channel. The mobile communication system according to any one of supplementary notes 9 to 16.

(Appendix 18)
The base station used in the mobile communication system according to any one of appendices 9 to 16,
A base station, comprising: a channel estimation unit configured to perform channel estimation of a channel used for transmission of the downlink quality information using the uplink pilot signal received from the mobile communication terminal as a reference channel.

(Appendix 19)
The downlink channel quality is measured, and the resulting downlink quality information indicating the downlink channel quality and the uplink pilot signal used for the uplink channel quality measurement are intermittently transmitted to the base station. A communication method,
A communication method comprising synchronizing a transmission timing of the downlink quality information and a transmission timing of the uplink pilot signal.

(Appendix 20)
The communication method according to appendix 19, wherein one of the transmission period of the downlink quality information and the transmission period of the uplink pilot signal is an integral multiple of the other.

(Appendix 21)
The communication method according to appendix 19, wherein the downlink quality information and the uplink pilot signal are transmitted simultaneously or successively.

(Appendix 22)
Both the downlink quality information and the uplink pilot signal are respectively transmitted on a part of locally existing carrier frequencies among a plurality of carrier frequencies allocated in advance in a predetermined frequency band. The communication method according to any one of supplementary notes 19 to 21.

(Appendix 23)
Both the downlink quality information and the uplink pilot signal are distributed in a part of the predetermined frequency band among a plurality of carrier frequencies assigned in advance in the predetermined frequency band. The communication method according to any one of appendices 19 to 21, wherein each of the transmissions is transmitted.

(Appendix 24)
A communication method of measuring downlink channel quality, and transmitting downlink quality information indicating the downlink channel quality obtained as a result and an uplink pilot signal used for uplink channel quality measurement to a base station. There,
The communication method, wherein the downlink quality information and the uplink pilot signal are transmitted at the same carrier frequency or a carrier frequency adjacent to each other among a plurality of pre-assigned carrier frequencies.

(Appendix 25)
Both the downlink quality information and the uplink pilot signal are respectively transmitted on a part of locally existing carrier frequencies among a plurality of carrier frequencies allocated in advance in a predetermined frequency band. The communication method according to attachment 24.

(Appendix 26)
Both the downlink quality information and the uplink pilot signal are distributed in a part of the predetermined frequency band among a plurality of carrier frequencies assigned in advance in the predetermined frequency band. 25. The communication method according to appendix 24, wherein each is transmitted.

(Appendix 27)
Any one of appendices 19 to 26, wherein the base station performs channel estimation of a channel used for transmission of the downlink quality information using the uplink pilot signal received by the base station as a reference channel. The communication method according to claim 1.

  The present invention is widely applicable to mobile communication terminals, mobile communication systems, and base stations in which downlink quality information and uplink pilot signals are transmitted from the mobile communication terminal to the base station. It can be suitably used for mobile communication terminals, mobile communication systems, and base stations that employ the 3.9th generation mobile communication system.

1 mobile communication system 2 radio base station controller N1 radio access network BS base station UE mobile communication terminal

Claims (6)

A mobile communication terminal that transmits downlink quality information indicating downlink channel quality and an uplink pilot signal to a base station,
The carrier frequency used for transmitting the downlink quality information and the carrier frequency for transmitting the uplink pilot signal can be selected from a plurality of carrier frequencies assigned in advance to the mobile communication terminal,
The mobile communication terminal includes a radio transmission unit that intermittently transmits the downlink quality information and the uplink pilot signal to the base station,
In the period according to the state of the intermittent transmission, the radio transmission unit uses the same carrier frequency among the plurality of carrier frequencies or the plurality of carrier frequencies for the downlink quality information and the uplink pilot signal. A mobile communication terminal that transmits at a carrier frequency adjacent to each other. A mobile communication system in which downlink quality information indicating downlink channel quality and an uplink pilot signal are transmitted to a base station,
The carrier frequency used for transmitting the downlink quality information and the carrier frequency for transmitting the uplink pilot signal can be selected from a plurality of carrier frequencies assigned in advance to the mobile communication terminal,
The mobile communication terminal includes a radio transmission unit that intermittently transmits the downlink quality information and the uplink pilot signal to the base station,
In the period according to the state of the intermittent transmission, the radio transmission unit uses the same carrier frequency among the plurality of carrier frequencies or the plurality of carrier frequencies for the downlink quality information and the uplink pilot signal. The mobile communication system characterized by transmitting on the mutually adjacent carrier frequency.   The base station comprises a channel estimation unit that performs channel estimation of a channel used for transmission of the downlink quality information using the uplink pilot signal received from the mobile communication terminal as a reference channel. The mobile communication system according to claim 2. The base station used in the mobile communication system according to claim 2,
A base station, comprising: a channel estimation unit configured to perform channel estimation of a channel used for transmission of the downlink quality information using the uplink pilot signal received from the mobile communication terminal as a reference channel. A communication method for transmitting downlink quality information indicating downlink line quality and an uplink pilot signal to a base station,
The carrier frequency used for transmitting the downlink quality information and the carrier frequency for transmitting the uplink pilot signal can be selected from a plurality of carrier frequencies assigned in advance to the mobile communication terminal,
Intermittently transmitting the downlink quality information and the uplink pilot signal to the base station;
In the period according to the intermittent transmission state, the downlink quality information and the uplink pilot signal are transmitted by using the same carrier frequency among the plurality of carrier frequencies or adjacent carriers among the plurality of carrier frequencies. A communication method characterized by transmitting at a frequency.   6. The base station according to claim 5, wherein channel estimation of a channel used for transmission of the downlink quality information is performed using the uplink pilot signal received by the base station as a reference channel. Communication method.

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