JP4824800B2 - Base station and reception method - Google Patents

Description

  The present invention relates to the technical field of wireless communication, and more particularly to a transmission apparatus and a reception apparatus used in the uplink.

  The next-generation wireless access system currently under research and development is required to perform communication more efficiently than the conventional system. In the downlink, high-speed and large-capacity communication is particularly required, and therefore, a multi-carrier wireless access method such as orthogonal frequency division multiple access (OFDM) is promising. On the other hand, the uplink is different from the downlink in that the request for higher speed and capacity is not as strong as the downlink and the transmission power of the mobile station is significantly limited compared to that of the base station. . For this reason, the multicarrier scheme that may increase the peak power to average power ratio (PAPR) cannot be said to be suitable for the uplink. Rather, from the viewpoint of suppressing PAPR and increasing cell coverage, it is desirable to adopt a single carrier scheme for the uplink.

  By the way, there are a data channel, a control channel, a pilot channel, and the like as channels transmitted in the uplink, and each channel includes various types of channels having different roles. For example, the pilot channel includes a pilot channel for channel compensation for radio resources that are not allocated, in addition to a pilot channel for channel compensation for allocated radio resources. In addition to the information used to demodulate the uplink data channel (for example, information indicating the modulation scheme and channel coding rate, etc.), the control channel has previously received acknowledgment information (ACK for the downlink data channel). / NACK) etc. may be included. The type and nature of the uplink channel are described in Patent Document 1, for example.

3GPP, TR25.814, "Physical Layer Aspects for Evolved UTRA"

  However, an appropriate uplink frame in consideration of the properties of various uplink channels as described above has not yet been determined. Furthermore, in the next-generation radio access scheme, a wide range of system frequency bands is prepared, and it is assumed that the mobile station performs communication using all or part thereof. However, an uplink frame suitable for use in a wide variety of bands has not yet been determined.

  The present invention has been made in order to address at least one of the above-described problems, and a problem thereof is a transmitting apparatus and a receiving apparatus for realizing an uplink frame suitable for transmitting various uplink channels. Is to provide.

In one embodiment, a base station used in a mobile communication system that employs a single carrier scheme in the uplink and has a system band divided by a plurality of resource blocks is used. This base station
A receiver for receiving a signal including a data channel, a first pilot channel not related to the data channel, a second pilot channel related to the data channel, and a control channel ;
A processing unit for processing a data channel, a first pilot channel, a second pilot channel , and a control channel included in a signal received by the receiving unit;
In the signal received by the receiving unit, the first pilot channel is mapped to a plurality of resource blocks, the second pilot channel is mapped to the same resource block as the resource block to which the data channel is mapped , and the control channel The base station is characterized in that the resource block to which the control channel is mapped is changed depending on whether or not the data channel is mapped to the same subframe .

  According to the present invention, an uplink frame suitable for transmitting various uplink channels can be realized.

FIG. 2 shows a schematic block diagram of a transmitter according to an embodiment of the present invention. 1 shows a schematic block diagram of a receiver according to an embodiment of the present invention. Shows a detailed view of the shared control channel generator. It is a figure which shows an example of the zone | band used by a system. It is a figure which shows a mode that the information of the user A and the user B is multiplexed by distributed type FDM. It is a figure which shows a mode that the information of the user A and the user B is multiplexed by CDM and distributed type FDM. It is a figure which shows a mode that the information of the user A and the user B is multiplexed by local FDM. It is a figure which shows the example of mapping of a pilot channel, a control channel, and a data channel. It is a figure which shows the example of mapping of a pilot channel, a control channel, and a data channel. It is a figure which shows the example of mapping of a pilot channel, a control channel, and a data channel. It is a figure which shows the example of mapping of a pilot channel, a control channel, and a data channel. It is a figure which shows the example of mapping of a pilot channel, a control channel, and a data channel.

  According to an aspect of the present invention, the first pilot channel for measuring the uplink channel state at the receiving apparatus is transmitted in a wide band, and the second pilot channel for compensating the channel transmitted in the uplink is It is transmitted in resource blocks allocated to the user equipment. For this reason, quality measurement for each resource block can be performed appropriately, and channel compensation of the allocated resource block can be performed appropriately.

  From the viewpoint of obtaining the frequency diversity effect while ensuring the orthogonality easily and reliably, the control channels of the local station and other stations may be orthogonalized by the distributed FDM method.

  From the viewpoint of transmitting the control channel with a resource block having a good channel state, it is desirable that the control channel of the own station is also transmitted within the resource block allocated for the data channel of the own station.

  From the viewpoint of particularly expecting the frequency diversity effect, even if the control channel of the local station is transmitted using not only the resource block for the data channel but also a wider band than the allocated resource block for the data channel of the local station. Good.

  From the viewpoint of improving throughput in consideration of the superiority or inferiority of the channel state of each user, the control channel of the own station may be transmitted in the frequency band of one or several resource blocks.

  The data channels of the own station and other stations may be orthogonalized by the FDM system, and the pilot channels of the own station and other stations may be orthogonalized by the CDM system.

  Before describing the apparatus configuration and operation according to an embodiment of the present invention, it is considered meaningful that various channels transmitted in the uplink are outlined. The uplink channels are roughly divided into (A) contention-based channels, (B) non-collision channels, and (C) pilot channels. The collision permissible channel is a channel that does not need to be scheduled at the base station before transmission, and the collision non-permissible channel is a channel (scheduled-channel) that needs to be scheduled at the base station before transmission. The collision tolerance channel includes one or more of (A1) a high-speed access channel, (A2) a reserved channel, and (A3) an uplink synchronization channel. The collision non-permissible channel includes one or more of (B1) uplink shared data channel and (B2) uplink shared control channel.

(A) [Collision allowable channel]
The collision-acceptable channel transmitted from the mobile station without scheduling at the base station can be transmitted at any time by the mobile station (more generally, user equipment (UE: user equipment) including a fixed station). The collision tolerant channel is preferably transmitted over a wide band. By doing so, the transmission time can be shortened. Further, even if the signal quality is greatly deteriorated at some frequencies, a frequency diversity effect is obtained because the band is wide, and power amplification (power ramping) or the like for compensating for the deterioration may not be essential. The collision-acceptable channel may compete between users, but can easily communicate at high speed. Although the same time division multiplexing (TDM) method as that of the current UTRA is used, in this embodiment, frequency division multiplexing (FDM) and / or code division multiplexing (CDM) is used from the viewpoint of reducing collisions with other users as much as possible. Done. However, if a collision occurs with another user, those users may retransmit the collision-acceptable channel as necessary.

(A1) Fast Access Channel
The high speed access channel may include small data size control messages, small data size traffic data, or both. One reason for limiting the data size to be small is to shorten the transmission delay. The control message may include, for example, information regarding layer 3 handover. The small size traffic data may include, for example, an e-mail with a small amount of information, a game command, or the like. Since the high speed access channel can be transmitted by the user apparatus to the base station without any reservation, the processing time required for transmission can be reduced. The high speed access channel is transmitted in one or more pre-assigned frequency chunks. Which of the plurality of frequency chunks should be transmitted may be notified from the base station to the user apparatus through a downlink broadcast channel (broadcast channel). The content of this notification may indicate that only one specific frequency chunk can be used, or may indicate that any one (or any number) of specific frequency chunks can be used. The latter is advantageous in that the probability of collision between users can be less than the former.

(A2) Reservation channel
The reserved channel includes information for requesting scheduling of a collision non-permissible channel. The information may include identification information for identifying the user device, a traffic data type (such as voice or image), a data size, required quality information (such as QoS), and transmission power of the user device. The reserved channel is also transmitted in a pre-assigned frequency chunk. Which of the plurality of frequency chunks should be transmitted may be notified from the base station to the user apparatus through a downlink broadcast channel (broadcast channel).

(A3) Uplink Synchronization Channel
In this embodiment, uplink signal transmission is performed by a single carrier scheme, and equalization is performed to suppress multipath interference. In order to perform effective equalization, it is desirable to maintain synchronization so that reception timings received from various users are within a predetermined guard interval. In order to maintain this synchronization, an uplink synchronization channel is used.

  Note that maintaining synchronization can also be realized by a pilot channel described later. Therefore, it is not essential to prepare both a synchronization channel and a pilot channel.

(B) [collision non-permissible channel]
The collision non-permissible channel is transmitted from the user equipment according to the scheduling performed at the base station.

(B1) Uplink Shared Data Channel
The uplink shared data channel includes traffic data and / or layer 3 control messages. The control message may include information related to handover, information necessary for retransmission control, and the like. One or more resource blocks (or chunks) are allocated to the uplink shared data channel according to scheduling in the time domain or both the time and frequency domains. In this case, resource allocation is planned at the base station (scheduling) so that users associated with better channels (channels) can transmit packets preferentially in the time domain or both time and frequency domains. ) The number of resource blocks to be allocated is determined depending on the data rate, data size, etc. that the user apparatus intends to transmit. When there are a plurality of users that require only a relatively low data rate, one resource block may be shared by a plurality of users. However, when the traffic size of a certain user exceeds a predetermined size, one resource block may be used by one user. One user may use a plurality of resource blocks. When one resource block is shared by a plurality of users, some multiplexing is performed so that the channels of the plurality of users are orthogonal to each other in the resource block. For example, local FDM or distributed FDM may be performed within one resource block.

(B2) Uplink Shared Control Channel
The uplink shared control channel transmits a physical control message and a layer 2 control message (FFS). For the uplink shared data channel, resource allocation is planned at the base station so that users associated with better channels (channels) can preferentially transmit packets. However, for the uplink shared control channel, scheduling that depends on the superiority or inferiority of the channel state is not essential (however, some link adaptation may be performed for the shared control channel). The base station allocates resource blocks to each user apparatus and performs scheduling so as to avoid contention for the shared control channel. For the uplink shared control channel, the base station performs scheduling depending on the number of users. In order to keep the packet error rate low, it is desirable to perform highly accurate transmission power control. Also, it is desirable to improve the quality of received packets by transmitting the uplink shared control channel over a wide frequency range and obtaining the frequency diversity effect.

  Specifically, the uplink shared control channel includes (1) control information related to a scheduled uplink shared data channel, (2) control information related to a scheduled downlink shared data channel, and (3) an uplink shared data channel. And (4) one or more pieces of control information for scheduling the downlink shared data channel. Among these various types of control information, (1) is essential control information that includes control information essential for demodulation of the uplink shared data channel and must accompany the uplink shared data channel. On the other hand, for (2) and (4), it is not essential to accompany the uplink shared data channel, and control information that does not have to accompany the uplink shared data channel (control information different from the essential control information) It is. According to such a classification method, the control information (3) related to the change of the scheduling content may be included in the essential control information, or may be included in control information different from the essential control information.

  (1) Control information (essential control information) related to the scheduled uplink shared data channel is transmitted along with the uplink shared data channel only when the uplink shared data channel is transmitted. This control information is also called an associated control channel and includes information necessary for demodulating the shared data channel (modulation scheme, channel coding rate, etc.), transmission block size, information on retransmission control, etc. For example, it may be expressed by an information amount of about 14 bits. For example, the retransmission control information may include information indicating whether a packet transmitted on the uplink shared data channel is a retransmission packet or a new packet, information indicating a method of using the retransmission packet, and the like. For example, in the first usage method, the data of the retransmission packet is the same as the data of the previously transmitted packet (for example, the first transmission data). However, in the second usage method, the data of the retransmission packet is the data of the previously transmitted packet. And may be different. In the latter case, packet combining can be performed together with redundant information for error correction coding.

  (2) The control information associated with the scheduled downlink shared data channel is transmitted to the base station only when the downlink shared data channel is transmitted from the base station and received by the user apparatus. This control information represents delivery confirmation information, that is, whether or not a packet has been properly received on the downlink (ACK / NACK), and can be represented by 1 bit in the simplest case.

  (3) Control information for changing the scheduling content of the uplink shared data channel is transmitted to notify the base station of the buffer size and / or transmission power of the user apparatus. This control information may be transmitted regularly or irregularly. For example, it may be transmitted from the user apparatus when the buffer size and / or transmission power changes. The base station may change the scheduling content according to such a change in the situation of the user equipment. The buffer size and transmission power status may be expressed by an information amount of about 10 bits, for example.

  (4) Control information for scheduling a downlink shared data channel is transmitted to notify downlink channel quality information (CQI: channel quality indicator) to the base station. The CQI may be a received SIR measured by a user apparatus, for example. This information may be sent regularly or irregularly. For example, it may be reported to the base station when the channel quality changes. This control information may be expressed by an information amount of about 5 bits, for example.

(C) [Pilot channel]
The pilot channel can be transmitted from the user equipment in time division multiplexing (TDM), frequency division multiplexing (FDM), code division multiplexing (CDM), or a combination thereof. However, it is desirable to use the TDM method from the viewpoint of reducing the peak-to-average power ratio (PAPR). By making the pilot channel and the data channel orthogonal by the TDM method, the pilot channel can be accurately separated on the receiving side, which can contribute to improvement of channel estimation accuracy.

  The pilot channel is used for channel compensation of the first pilot channel for CQI measurement for all resource blocks that may be allocated to the local station in the future and the channel transmitted in the resource block currently allocated to the local station. Of the second pilot channel. As will be described later, the first pilot channel is transmitted in a wide band including all resource blocks, and the second pilot channel is transmitted only by a specific resource block assigned to the own station.

  FIG. 1 shows a schematic block diagram of a transmitter according to an embodiment of the present invention. The illustrated transmitter is typically provided in a user device. In FIG. 1, a pilot channel generation unit 231, a shared control channel generation unit 233, a shared data channel generation unit 234, a multiplexing unit 235, a discrete Fourier transform unit (DFT) 236, a mapping unit 237, and a fast inverse Fourier transform unit 238 are depicted. ing.

  The pilot channel generation unit 231 generates a pilot channel used in the uplink. The pilot channel includes at least the first and second pilot channels.

  The shared control channel generation unit 233 generates a shared control channel that may include various control information. The shared control channel generation unit 233 will be described later with reference to FIG.

  The shared data channel generation unit 234 generates a shared data channel transmitted on the uplink.

  The multiplexing unit 235 multiplexes and outputs one or more of various channels. It is not essential that all the illustrated channels are multiplexed, and one or more channels are multiplexed as necessary. In the example shown in the figure, the multiplexing unit 235 performs time division multiplexing processing, and the mapping unit 237 performs allocation processing to frequency components. Since these time-division multiplexed signals are scheduled according to instructions from the base station, they are classified as collision non-permissible channels.

  In practice, a collision-acceptable channel is also generated and multiplexed as necessary, but this is omitted for the sake of simplicity.

  A discrete Fourier transform unit (DFT) 236 performs a Fourier transform on the signal (the multiplexed signal in the illustrated example) input thereto. At this stage of signal processing, the signal is a discrete digital value, so a discrete Fourier transform is performed. Thereby, a series of signal sequences arranged in time order are expressed in the frequency domain.

  The mapping unit 237 maps each signal component after Fourier transform to a predetermined subcarrier on the frequency domain. In this case, the frequency division multiplexing (FDM) system may be a localized or local FDM system (localized FDM) in which one continuous narrow band is assigned to one user, and a plurality of frequency components have a predetermined frequency. A distributed type or distributed type FDMA (distributed FDM) system that gives spectrums that are dispersed and arranged at intervals may be used. The predetermined frequency intervals are generally equal intervals, but may be unequal intervals. The mapping unit 237 performs mapping on the frequency axis using a local FDM or a distributed FDM.

  The fast inverse Fourier transform unit 238 performs fast inverse Fourier transform on the mapped signal components and outputs a signal sequence arranged in a series of time sequences.

  The distributed FDM may be realized by, for example, a variable spreading factor chip repetition factor CDM (VSCRF-CDM: Variable Spreading and Chip Repetition Factors-CDM) method.

  FIG. 2 shows a schematic block diagram of a receiver according to an embodiment of the present invention. The illustrated receiver is typically provided in a base station. FIG. 2 illustrates a discrete Fourier transform unit (DFT) 241, a mapping unit 242, a fast inverse Fourier transform unit 243, and a multiplexing unit 244.

  A discrete Fourier transform unit (DFT) 241 performs a Fourier transform on a signal (received signal in the illustrated example) input thereto. Thereby, a series of signal sequences arranged in time order are expressed in the frequency domain.

  The mapping unit 242 extracts a predetermined subcarrier component from the signal after Fourier transform. As a result, for example, signals multiplexed by a local type FDM or a distributed type FDM are separated.

  The fast inverse Fourier transform unit 242 performs fast inverse Fourier transform on the separated signal components and outputs a signal sequence arranged in a series of time sequences.

  The separation unit 244 separates and outputs one or more of various channels. In the illustrated example, the signal mapped to the frequency component is restored to the signal before mapping by the demapping unit 242, and the time-multiplexed signal is separated by the separation unit 244.

  One or more channels generated by the generation unit of each channel in FIG. 1 are time-multiplexed (switched appropriately) by the multiplexing unit 235, input to the DFT 236, and converted into a frequency domain signal. The converted signal is appropriately mapped to frequency components by the mapping unit 237, input to the IFFT 238, and converted into a time-series signal. Thereafter, the signal is wirelessly transmitted through a processing element such as the RF unit 14 in FIG. This signal is received by the receiver of FIG. The received signal is input to the DFT 241 and converted into a frequency domain signal. The converted signal is a signal mapped to the frequency component, but is separated into a signal before mapping by the demapping unit 242. The separated signal is converted into a time-series signal by IFFT 243, and the time-multiplexed signal series is appropriately separated by separation section 244, and further demodulated by a processing element (not shown).

  FIG. 3 shows a detailed view of the shared control channel generation unit 233. In FIG. 3, switches 251, 252, and 253, modulation and encoding units 255, 256, 257, and 258 and a multiplexing unit 259 are depicted. Each switch gives each channel inputted to one end (left side in the figure) to the other end according to an instruction signal (not shown) relating to the shared control channel. The content of the instruction signal determines how to configure the shared control channel, that is, what control information is included in the shared control channel. In the illustrated example, as control information that may be included in the shared control channel, (1) essential control information, (2) downlink acknowledgment information (information indicating an acknowledgment (ACK) and a negative response (NACK)) , (3) information for changing the contents of scheduling, and (4) channel state information (CQI) indicating the reception quality of the downlink pilot channel.

  Each of the modulation and encoding unit performs data modulation on the input channel using the specified modulation method, and performs channel encoding using the specified encoding method. The modulation scheme and coding scheme used for each channel may be different for each channel, and the same scheme may be used for two or more channels. The modulation scheme or the coding scheme may be fixedly set unchanged.

  The multiplexing unit 259 multiplexes each channel, creates a shared control channel, and outputs it.

  In the transmission of the conventional shared control channel, the modulation scheme and the coding scheme are fixed, and it is intended to obtain the required quality by controlling the transmission power control. However, from the viewpoint of improving the quality of the channel and effectively using resources, it is desirable to perform further link adaptation for transmission of the shared control channel. Examples of methods for performing link adaptation include adaptive modulation and coding (AMC) and transmission power control (TPC) control.

  FIG. 4 shows a frequency band used in a certain communication system. A frequency band given to the system (also referred to as an entire frequency band or a system band) includes a plurality of system frequency blocks, and the user apparatus performs communication using one or more resource blocks included in the system frequency block. be able to. Such a resource block is also called a chunk or a frequency chunk. In general, one chunk may include one or more carriers (also referred to as subcarriers). However, in one embodiment of the present invention, a single carrier scheme is adopted and only one carrier is included in one chunk. Not.

  In the example of FIG. 4, the system band is 10 MHz, the system frequency block is 5 MHz, and the system band includes two system frequency blocks. For simplicity of illustration, the system frequency block 2 is not drawn. The resource block is 1.25 MHz, and one system frequency block includes four resource blocks. Which of the two system frequency blocks can be used by the user apparatus is determined by the base station according to the bandwidth in which the user apparatus can communicate and the number of users communicating in the system. The bandwidth of the system frequency block is designed as a band in which all user apparatuses that can communicate in the system can communicate. In other words, the bandwidth of the system frequency block is determined as the maximum transmission bandwidth for the assumed lowest grade user equipment. Accordingly, only one of the system frequency blocks can be assigned to a user apparatus that can communicate only in the 5 MHz band, but the user apparatus capable of communicating in the 10 MHz band has a band so that both system frequency blocks can be used. May be assigned. In the present embodiment, the subframe may be referred to as a transmission time interval (TTI) such as 0.5 ms, but any suitable period may be used. These numerical examples are merely examples, and any appropriate numerical values may be used.

  The user apparatus transmits an uplink pilot channel to the base station. Based on the reception quality of the uplink pilot channel, the base station determines (schedules) which one or more resource blocks to be used by the user apparatus for transmission of the shared data channel. The content of scheduling (scheduling information) is notified to the user apparatus through the downlink shared control channel or another channel. The user apparatus transmits the uplink shared data channel using the allocated resource block. In this case, a shared control channel (shared control channel including essential control information) associated with the uplink shared data channel is also transmitted in the same resource block. As described above, the uplink shared control channel may include control information other than the essential control information.

  Resource blocks allocated to a user may change over time. Resource blocks allocated to users may follow a certain frequency hopping pattern. The contents of the hopping pattern may be known before the start of communication between the base station and the user apparatus, or may be notified from the base station to the user apparatus as necessary. From the viewpoint of maintaining the average signal quality of the uplink channel, it is desirable to use various resource blocks as well as specific resource blocks.

  FIGS. 5A to 5C show specific examples of how user A and user B information are multiplexed in one subframe. In the example of FIG. 5A, the pilot channel and the data channel are time multiplexed. Information on user A and user B is multiplexed by distributed FDM. In the example of FIG. 5B, the pilot channel and the data channel are time-multiplexed, and the data channels of the user A and the user B are multiplexed by the distributed FDM. The pilot channel is multiplexed by CDM. In the example of FIG. 5C, the pilot channel and the data channel are time-multiplexed, and the data channels of user A and user B are multiplexed by local FDM.

  FIG. 6A shows an example of information mapping for each user according to an embodiment of the present invention. The illustrated range is the entire frequency band and one subframe, but the frequency axis direction may be within the range of one system frequency block. For convenience of explanation, the period in the subframe is divided into first to fourth time slots in order of time passage. In the first time slot, the first pilot channels from all users are multiplexed and transmitted. All users include all users who may transmit some channel in the future in addition to users transmitting uplink data channels and users transmitting uplink control channels. As described above, the first pilot channel is a pilot channel for CQI measurement for all resource blocks that may be allocated to the own station in the future. The multiplexing of the first pilot channel for all users may be performed by FDM, CDM, or both.

  The control channel is mapped in the second time slot. The control channels of each user are orthogonal to each other by distributed FDM. As described above, the information included in the shared control channel includes essential control information essential for demodulation of the shared data channel and other control information (control information other than essential control information). In the illustrated example, users B, C, and D transmit a control channel including control information other than the essential control information. Users B, C, and D distribute the control channel over the entire frequency band (or the entire system frequency block) in the same manner as the first pilot channel, and transmit it to the base station. It is assumed that users B, C, and D do not transmit a data channel in any resource block in this subframe. User A is assigned one resource block and transmits the data channel in the third time slot in that resource block. User A's control channel (including essential control information and other control information) is transmitted using the frequency in the resource block allocated to user A. The control channel of user A and the control channels of other users are also orthogonal to each other by distributed FDM.

  In the fourth time slot, the second pilot channel is mapped. As described above, the second pilot channel is a pilot channel for channel compensation of a channel transmitted in the resource block currently allocated to the own station. Also in this fourth time slot, the first pilot channel transmitted in a wide band for CQI measurement may be multiplexed by a plurality of users. Even in this case, it is possible to perform channel compensation of the channel transmitted in the resource block currently allocated to the own station by using a part of the first pilot channel transmitted in a wide band.

  Note that, for simplification of illustration, data channels of users other than the user A are not shown, but in actuality, some user (users B, C, D) may be included in resource blocks other than the resource blocks allocated to the user A. Other) data channels and the like are mapped.

  For the uplink channel received from user A, the base station estimates the channel state of the resource block based on the second pilot channel and determines the compensation content (phase rotation amount, power, etc.) to be applied to the control channel and data channel. And compensate. In addition, based on the first pilot channel, it is determined which resource block has higher quality for user A in the subsequent subframes. Based on uplink channels (control information other than essential control information) received from users B, C, and D, the base station performs retransmission control and the like. If an uplink resource allocation request has been made, the base station determines which resource block has the high quality for the users B, C, or D based on the received first pilot channel.

  From the viewpoint of the base station appropriately determining the superiority or inferiority of the channel state of each user for each resource block, it is desirable that the first pilot channel is transmitted in a wide band. From the standpoint of enhancing the frequency diversity effect and ensuring the minimum reception quality at the base station, the control channels of users B, C, and D that are not assigned specific resource blocks are widened as shown in the example in the figure. It is desirable to be dispersed. From the viewpoint of transmitting the control channel in a channel state as good as possible, it is desirable that the control channel of user A to which a specific resource block is allocated is transmitted in a resource block that is divided as in the illustrated example. In this case, the second pilot channel transmitted in the divided resource block can also be used for demodulating the control channel of user A.

  FIG. 6B shows an example of information mapping for each user according to an embodiment of the present invention. For convenience, the time slot is divided into first to fifth five. The first, second, fourth, and fifth time slots are the same as the first to fourth time slots in FIG. 6A. However, in FIG. 6B, in the third time slot (before the user A data channel is transmitted), a control channel including control information other than the user A essential control information is transmitted. In the illustrated example, in the control channel of user A, the essential control information is transmitted in the second time slot, and control information other than the essential control information is transmitted in the third time slot. Such a method is advantageous when the amount of control information other than the essential control information is large (for example, when the control information other than the essential control information is difficult to transmit by the method of FIG. 6A). is there.

  FIG. 7 shows an example of information mapping for each user according to an embodiment of the present invention. 6A is generally the same as the example shown in FIG. 6A, but the control channels (including only control information other than the essential control information) transmitted by users B, C, and D are not distributed over the entire frequency band. The difference is that it falls within the category. If the channel state for a specific resource block is relatively good, it is desirable that the control channel is transmitted in the specific resource block as shown in FIG.

  FIG. 8 shows an example of information mapping for each user according to an embodiment of the present invention. 6A is generally the same as the example shown in FIG. 6A, but not only the control channels (including only control information other than the essential control information) transmitted by users B, C, and D, but also the control channel of user A in the entire frequency band. The difference is that it is distributed.

  FIG. 9 shows an example of information mapping for each user according to an embodiment of the present invention. In the mapping examples of FIGS. 6A to 8, only the data channel of user A is shown, but in FIG. 9, the data channels of other users are also shown. FIG. 9 shows a mapping example for two subframes. As shown in the figure, the mapping method may change variously with time.

  Hereinafter, the means taught by the present invention will be listed as an example.

(Section 1)
A transmission device used in a mobile communication system employing a single carrier scheme in uplink,
A multiplexing means for multiplexing the pilot channel, the control channel and the data channel;
Transmission means for transmitting transmission symbols including at least a pilot channel and a control channel in the uplink;
And the pilot channel includes a first pilot channel for measuring an uplink channel state at a receiving device, and a second pilot channel for compensating a channel transmitted on the uplink,
The data channel is transmitted using one or more resource blocks;
The first pilot channel is transmitted in a frequency band over a plurality of resource blocks;
The second pilot channel is transmitted in a resource block allocated to the own station,
A transmitting apparatus characterized in that the control channels of the local station and other stations are orthogonalized by a frequency division multiplexing (FDM) method.

(Section 2)
2. The transmission apparatus according to claim 1, wherein the control channels of the local station and other stations are orthogonal to each other by a distributed FDM system.

(Section 3)
The transmitting apparatus according to claim 1, wherein the control channel of the own station is transmitted by a resource block allocated for the data channel of the own station.

(Section 4)
The transmitting apparatus according to claim 1, wherein the control channel of the local station is transmitted using a wide band equal to or larger than the resource block allocated for the data channel of the local station.

(Section 5)
The transmission apparatus according to claim 1, wherein the control channel of the own station is transmitted in a frequency band of one or several resource blocks.

(Section 6)
Transmission according to claim 1, characterized in that the data channels of the local station and other stations are orthogonal to each other by frequency division multiplexing (FDM), and the pilot channels of the local station and other stations are code division multiplexed (CDM). apparatus.

(Section 7)
A receiving apparatus used in a mobile communication system adopting a single carrier scheme in uplink,
Receiving means for receiving transmission symbols including a pilot channel, a control channel, and a data channel on the uplink;
Separating means for separating a pilot channel, a control channel and a data channel from received symbols;
And the pilot channel includes a first pilot channel for measuring an uplink channel state at a receiving device, and a second pilot channel for compensating a channel transmitted on the uplink,
The data channel is received in one or more resource blocks;
The first pilot channel is received in a frequency band spanning a plurality of resource blocks;
The second pilot channel is a resource block assigned to an individual transmitter,
A receiving apparatus characterized in that the control channels of the local station and other stations are orthogonalized with each other by frequency division multiplexing (FDM).

231 Pilot channel generation section 233 Shared control channel generation section 235 Shared data channel generation section 236, 241 Discrete Fourier transform section 237, 242 Mapping section 238, 243 Fast inverse Fourier transform section 244 Separation section 251-253 Switch 255-258 Modulation and code 259 Multiplexer

Claims (10)

A base station that is used in a mobile communication system that adopts a single carrier scheme in uplink and that divides a system band by a plurality of resource blocks,
A receiver for receiving a signal including a data channel, a first pilot channel not related to the data channel, a second pilot channel related to the data channel, and a control channel ;
A processing unit for processing a data channel, a first pilot channel, a second pilot channel , and a control channel included in a signal received by the receiving unit;
In the signal received by the receiving unit, the first pilot channel is mapped to a plurality of resource blocks, the second pilot channel is mapped to the same resource block as the resource block to which the data channel is mapped , and the control channel A base station characterized in that a resource block to which a control channel is mapped is changed depending on whether or not a data channel is mapped to the same subframe . In the signal received by the receiving unit, in the subframe to which the data channel is mapped, the control channel is also mapped to the resource block to which the data channel is mapped. The base station according to claim 1, wherein a control channel is mapped to a resource block other than the resource block assigned to the channel . The base station according to claim 1 or 2 , wherein the processing unit uses the first pilot channel for measurement and uses the second pilot channel for demodulation of the data channel. 4. The base station according to claim 1 , wherein a data channel, a first pilot channel, and a second pilot channel are time-division multiplexed in the signal received by the receiving unit. 5. The base station according to claim 1 , wherein a control channel is mapped to one or several resource blocks in the signal received by the receiving unit. A reception method used in a base station of a mobile communication system that adopts a single carrier scheme in uplink and that divides a system band by a plurality of resource blocks,
Receiving a signal including a data channel, a first pilot channel not associated with the data channel, a second pilot channel associated with the data channel, and a control channel ;
Processing the data channel, the first pilot channel, the second pilot channel , and the control channel included in the received signal,
In the signal received in the receiving step, the first pilot channel is mapped to a plurality of resource blocks, the second pilot channel is mapped to the same resource block as the resource block to which the data channel is mapped , and the control channel And the data channel is mapped to the same subframe, the resource block to which the control channel is mapped is changed . In the signal received in the receiving step, in the subframe to which the data channel is mapped, the control channel is also mapped to the resource block to which the data channel is mapped, and in the subframe to which the data channel is not mapped, The receiving method according to claim 6, wherein a control channel is mapped to a resource block other than the resource block allocated to the data channel . The receiving method according to claim 6 or 7 , wherein the processing step uses the first pilot channel for measurement and uses the second pilot channel for demodulation of the data channel. 9. The receiving method according to claim 6 , wherein the data channel, the first pilot channel, and the second pilot channel are time-division multiplexed in the signal received in the receiving step. 10. The receiving method according to claim 6 , wherein a control channel is mapped to one or several resource blocks in the signal received in the receiving step.

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