JP5417409B2 - Wireless communication system, base station apparatus, mobile station apparatus, wireless communication method, and integrated circuit - Google Patents

Description

  The present invention relates to a radio communication system, a base station apparatus, a mobile station apparatus, a radio communication method, and an integrated circuit.

  The evolution of wireless access methods and wireless networks for cellular mobile communications (hereinafter referred to as “Long Term Evolution (LTE)” or “Evolved Universal Terrestrial Radio Access (EUTRA)”) is the third generation partnership project (3rd Generation Partnership Project: 3GPP). In LTE, an Orthogonal Frequency Division Multiplexing (OFDM) system, which is multicarrier transmission, is used as a wireless communication (downlink) communication system from a base station apparatus to a mobile station apparatus. Further, as a communication system for radio communication (uplink) from the mobile station apparatus to the base station apparatus, an SC-FDMA (Single-Carrier Frequency Division Multiple Access) system that is single carrier transmission is used.

  In LTE, a base station apparatus uses a PUSCH (Physical Uplink Shared Channel) that is a data transmission channel transmitted from a mobile station apparatus and a PDSCH (Physical Downlink Shared Channel) that is a data transmission channel transmitted from the base station apparatus. Radio resource allocation, coding rate, modulation scheme, etc. are determined. Also, the base station apparatus transmits downlink control information (Downlink Control Information: DCI) indicating the radio resource allocation and the like to the mobile station apparatus using a PDCCH (Physical Downlink Control Channel).

  Hereinafter, the PDCCH will be described in more detail. The PDCCH is arranged in one or more control channel elements (Control Channel Element: CCE). The control channel element is a unit of radio resources in which the PDCCH is arranged. Further, a common search area (Common Search Space) and a mobile station apparatus specific search area (User Equipment-specific Search Space) are configured from a plurality of control channel elements.

  The common search area is an area common to a plurality of mobile station apparatuses, and is an area where a PDCCH for a plurality of mobile station apparatuses and / or a PDCCH for a specific mobile station apparatus is arranged. The common search area is composed of predetermined control channel elements. The mobile station apparatus specific search area is an area where a PDCCH for a specific mobile station apparatus is arranged, and is an area configured for each mobile station apparatus. The common search area and the mobile station apparatus specific search area are configured with different common search areas and mobile station apparatus specific search areas for each number of control channel elements in which the PDCCH is arranged. Note that part or all of the common search area and the mobile station apparatus specific search area may overlap, or part or all of different common search areas may overlap, and different mobile stations for the same mobile station apparatus 1 Some or all of the device-specific search areas may overlap, or some or all of the mobile station device-specific search areas for different mobile station devices 1 may overlap.

  A plurality of formats are prepared for downlink control information transmitted on the PDCCH. The format of the downlink control information is called a DCI format (DCI format). Some DCI formats have the same number of bits as other DCI formats (also referred to as “payload size”) and others. The base station apparatus downlinks a sequence in which a cyclic redundancy check (CRC) code generated based on downlink control information is scrambled (referred to as scramble or mask) with RNTI (Radio Network Temporary Identity). Append to

  The mobile station apparatus changes the interpretation of the downlink control information depending on which RNTI the cyclic redundancy check code is scrambled. Hereinafter, the addition of the cyclic redundancy check code scrambled with the RNTI to the downlink control information is simply expressed as the RNTI included in the downlink control information or the RNT included in the PDCCH. For example, the mobile station apparatus determines the type of the DCI format of the downlink control information from the RNTI included in the downlink control information.

  The base station apparatus encodes the downlink control information according to the number of bits of the control channel element, and arranges it in the common search area or the mobile station apparatus specific search area. Note that the base station apparatus performs the same encoding for the DCI format having the same number of bits and performs the different encoding for the DCI format having a different number of bits. That is, since the encoding method applied to the DCI format by the base station apparatus 3 differs depending on the number of bits in the DCI format, the method of decoding the DCI format in the mobile station apparatus differs depending on the number of bits in the DCI format. Therefore, the mobile station apparatus can determine the type of DCI format from the number of bits in the DCI format or the difference in decoding method. When the number of bits of the DCI format is the same, the DCI format includes information for determining the type of the DCI format, or a cyclic redundancy check code scrambled with the RNTI corresponding to the type of the DCI format is added. Is used to enable the mobile station apparatus 1 to determine the type of the DCI format.

  The mobile station apparatus 1 decodes all control channel element candidates in which the PDCCH is arranged in the common search area and the mobile station apparatus specific search area, and further scrambles a sequence obtained by scrambling the cyclic redundancy check code with the RNTI ( When it is detected that there is no error in the descrambled cyclic redundancy check code, it is determined that acquisition of the PDCCH is successful. This process is called blind decoding.

  In 3GPP, a radio access method and a radio network (hereinafter referred to as “Long Term Evolution-Advanced (LTE-A)” or “ Advanced Evolved Universal Terrestrial Radio Access (A-EUTRA) ”). LTE-A has backward compatibility with LTE, that is, a base station apparatus of LTE-A performs radio communication simultaneously with mobile station apparatuses of both LTE-A and LTE, and LTE. -A mobile station apparatus is required to be able to perform radio communication with both LTE-A and LTE base station apparatuses, and it is considered that LTE-A uses the same channel structure as LTE. Yes.

  In LTE-A, a technology that uses a plurality of frequency bands having the same channel structure as LTE (hereinafter referred to as “Component Carrier (CC)”) as a single frequency band (broadband frequency band). (Frequency band aggregation; also referred to as spectrum aggregation, carrier aggregation, frequency aggregation, etc.) has been studied. Specifically, in communication using frequency band aggregation, a downlink channel is transmitted for each downlink component carrier, and an uplink channel is transmitted for each uplink component carrier. In other words, in frequency band aggregation, in the uplink and downlink, the base station apparatus and the plurality of mobile station apparatuses simultaneously transmit and receive a plurality of data information and a plurality of control information using a plurality of channels and a plurality of carrier elements. Technology.

"3GPP TS36.213 v.9.0.1 (2009-12)", 2009-12-18.

  However, in the conventional technology, the common search area and the mobile station apparatus specific search area overlap, that is, the same number and the same number of control channel element candidates for arranging the PDCCH in the common search area and the mobile station apparatus specific search area are the same. When the RNTI included in the PDCCH is the same and the number of bits of the DCI format transmitted in each of the common search area and the mobile station apparatus specific search area is the same, the mobile station apparatus sets the type of the DCI format. There was a problem that it could not be identified.

  The present invention has been made in view of the above points, and an object of the present invention is to allow a mobile station apparatus to identify the type of DCI format in a wireless communication system in which a common search area and a mobile station apparatus specific search area overlap. An object of the present invention is to provide a wireless communication system, a base station device, a mobile station device, a wireless communication method, and an integrated circuit.

  (1) In order to achieve the above object, the present invention takes the following measures. That is, the radio communication system of the present invention is a radio communication system having a mobile station apparatus and a base station apparatus that transmits control information to the mobile station apparatus. The base station apparatus is a candidate for arranging the control information. A payload size of each control information of a physical downlink control channel candidate in a common search area and a physical downlink control channel candidate in a mobile station apparatus specific search area is the same, and each of the control information includes different information, When the physical downlink control channel candidate in the common search area and the physical downlink control channel candidate in the mobile station apparatus specific search area are configured by control channel elements having the same number, the physical downlink in the common search area The control information is arranged and transmitted only to control channel candidates, and the mobile station apparatus performs physical downlink only in the common search area. As the control information using the click control channel is transmitted, and performs reception processing of the control information.

  (2) In addition, the base station apparatus of the present invention, in the base station apparatus that transmits control information to the mobile station apparatus, moves with the physical downlink control channel candidate in the common search area, which is a candidate for arranging the control information. The payload size of each control information of the physical downlink control channel candidate in the station apparatus specific search region is the same, each control information includes different control information, and the physical downlink control channel candidate in the common search region and the When the physical downlink control channel candidate in the mobile station apparatus specific search region is composed of control channel elements having the same number, the control information is arranged and transmitted only in the physical downlink control channel candidate in the common search region. It is characterized by doing.

  (3) Moreover, the mobile station apparatus of this invention is a mobile station apparatus which receives the control information transmitted from a base station apparatus, The common search area | region which is a candidate by which the said control information is arrange | positioned in the said base station apparatus The payload size of each control information of the physical downlink control channel candidate of the physical downlink control channel candidate and the physical downlink control channel candidate of the mobile station device specific search region are the same, and each of the control information includes different control information, the common search region If the physical downlink control channel candidate and the physical downlink control channel candidate in the mobile station apparatus specific search region are composed of the same number of control channel elements, the physical downlink control channel is only used in the common search region. When the control information is transmitted using the control information, the control information is received.

  (4) In addition, the radio communication method of the present invention is a radio communication method used in a base station apparatus that transmits control information to a mobile station apparatus, and is a physical download in a common search area that is a candidate for arranging the control information. The payload size of the control information of each of the link control channel candidate and the physical downlink control channel candidate of the mobile station apparatus specific search area is the same, each of the control information includes different control information, and the physical downlink of the common search area When the link control channel candidate and the physical downlink control channel candidate in the mobile station apparatus specific search region are composed of control channel elements having the same number, the control is performed only on the physical downlink control channel candidate in the common search region. It is used for a base station apparatus characterized in that information is arranged and transmitted.

  (5) Moreover, the radio communication method of the present invention is a radio communication method used for a mobile station apparatus that receives control information transmitted from a base station apparatus. In the radio communication method, candidates for arranging the control information in the base station apparatus are provided. Control information having the same payload size in the control information of the physical downlink control channel candidate in the common search region and the physical downlink control channel candidate in the mobile station apparatus specific search region, the control information being different from each other. And if the physical downlink control channel candidate in the common search area and the physical downlink control channel candidate in the mobile station apparatus specific search area are composed of control channel elements having the same number, only in the common search area The control information is received on the assumption that the control information is transmitted using a physical downlink control channel. Used in the mobile station apparatus.

  (6) Further, the integrated circuit of the present invention is a physical downlink control of a common search area, which is a candidate for arranging the control information, in an integrated circuit used in a base station apparatus that transmits control information to a mobile station apparatus. The physical downlink control of the common search region includes the same control information payload size of the channel candidate and the physical downlink control channel candidate of the mobile station apparatus specific search region, each of the control information includes different control information When the channel candidate and the physical downlink control channel candidate in the mobile station apparatus specific search region are configured by the same number of control channel elements, the control information is only added to the physical downlink control channel candidate in the common search region. It is used for a base station apparatus characterized by being arranged and transmitted.

  (7) Moreover, the integrated circuit of the present invention is a candidate for arranging the control information in the base station device in an integrated circuit used in a mobile station device that receives control information transmitted from the base station device. The payload size of each control information of the physical downlink control channel candidate in the common search area and the physical downlink control channel candidate in the mobile station apparatus specific search area are the same, and each of the control information includes different control information, When the physical downlink control channel candidate in the common search area and the physical downlink control channel candidate in the mobile station apparatus specific search area are configured by control channel elements having the same number, physical downlink only in the common search area A mobile station, wherein the control information is received on the assumption that the control information is transmitted using a link control channel It used to location.

  According to the present invention, the mobile station apparatus can identify the type of DCI format.

1 is a conceptual diagram of a wireless communication system according to a first embodiment of the present invention. It is a figure which shows an example of the frequency band aggregation process of this invention. It is the schematic which shows an example of a structure of the downlink radio frame of this invention. It is the schematic which shows an example of the search area | region of this invention. It is the schematic which shows the encoding method and arrangement | positioning method of downlink control information of this invention. It is a flowchart figure which shows an example of operation | movement of the mobile station apparatus 1 and the base station apparatus 3 of this invention. It is a schematic block diagram which shows the structure of the base station apparatus 3 of this invention. It is a schematic block diagram which shows the structure of the mobile station apparatus 1 of this invention. It is the schematic which shows an example of the search area | region which concerns on the 3rd Embodiment of this invention.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a conceptual diagram of a radio communication system according to the first embodiment of the present invention. In FIG. 1, the radio communication system includes mobile station apparatuses 1 </ b> A to 1 </ b> C and a base station apparatus 3. FIG. 1 shows a synchronization channel (SCH), a downlink pilot channel (or “Downlink Reference Signal” in wireless communication (downlink) from the base station device 3 to the mobile station devices 1A to 1C. : DL RS))), Physical Broadcast Channel (PBCH), Physical Downlink Control Channel (PDCCH), Physical Downlink Shared Channel (PDSCH), Physical It shows that a multicast channel (Physical Multicast Channel: PMCH), a physical control format indicator channel (Physical Control Format Indicator Channel: PCFICH), and a physical HARQ indicator channel (Physical Hybrid ARQ Indicator Channel: PHICH) are allocated.

  1 is also referred to as an uplink pilot channel (or “Uplink Reference Signal (UL RS)” in radio communication (uplink) from the mobile station apparatuses 1A to 1C to the base station apparatus 3. )), A physical uplink control channel (PUCCH), a physical uplink shared channel (PUSCH), and a physical random access channel (PRACH). Hereinafter, the mobile station apparatuses 1A to 1C are referred to as the mobile station apparatus 1.

  FIG. 2 is a diagram illustrating an example of the frequency band aggregation processing according to the present invention. In FIG. 2, the horizontal axis represents the frequency domain, and the vertical axis represents the time domain. As shown in FIG. 2, the downlink subframe D1 includes three downlink component carriers (DL CC-1; Downlink Component Carrier-1, DL CC-2, DL CC-3, DL CC-1; DL CC-4) subframes. In each subframe of the downlink component carrier, a region where the PDCCH indicated by the hatched region is arranged and a region where the PDSCH indicated by the non-hatched region is time-multiplexed. For example, the base station apparatus 3 arranges a signal on the PDSCH of one or a plurality of downlink component carriers out of three downlink component carriers in a certain downlink subframe, and transmits the signal to the mobile station apparatus 1.

  On the other hand, the uplink subframe U1 is composed of three component carriers (UL CC-1; Uplink Component Carrier-1, UL CC-2, UL CC-3) having a bandwidth of 20 MHz. In each subframe of the uplink component carrier, an area where the PUCCH indicated by the hatched area is arranged and an area where the PUSCH indicated by the left hatched area is arranged are arranged. The area to be frequency-multiplexed. For example, the mobile station apparatus 1 arranges a signal on the PUSCH of one or a plurality of uplink component carriers among three uplink component carriers in a certain uplink subframe, and transmits the signal to the base station apparatus 3.

  FIG. 3 is a schematic diagram illustrating an example of a configuration of a downlink radio frame according to the present invention. FIG. 3 shows a configuration of a radio frame in a certain downlink component carrier. In FIG. 3, the horizontal axis is the time domain, and the vertical axis is the frequency domain. As shown in FIG. 3, the radio frame of the downlink component carrier is composed of a plurality of downlink physical resource block (PRB) pairs (for example, an area surrounded by a broken line in FIG. 3). . This downlink physical resource block pair is a unit such as radio resource allocation, and has a predetermined frequency band (PRB bandwidth; 180 kHz) and time band (2 slots = 1 subframe; 1 ms).

  One downlink physical resource block pair is composed of two downlink physical resource blocks (PRB bandwidth × slot) that are continuous in the time domain. One downlink physical resource block (unit surrounded by a thick line in FIG. 3) is composed of 12 subcarriers (15 kHz) in the frequency domain, and 7 OFDM (Orthogonal Frequency Division) in the time domain. Multiplexing) symbol (71 μs).

  In the time domain, a slot composed of 7 OFDM symbols (71 μs) (0.5 ms), a subframe composed of 2 slots (1 ms), and a radio frame composed of 10 subframes ( 10 ms). In the frequency domain, a plurality of downlink physical resource blocks are arranged according to the bandwidth of the downlink component carrier. A unit composed of one subcarrier and one OFDM symbol is referred to as a downlink resource element.

  Hereinafter, a channel allocated in a downlink radio frame will be described. In each downlink subframe, for example, a PDCCH, a PDSCH, and a downlink reference signal are allocated. First, PDCCH will be described. The PDCCH is arranged from the first OFDM symbol of the subframe (the area hatched with a left oblique line in FIG. 3). Note that the number of OFDM symbols in which the PDCCH is arranged is 1 to 3, and is different for each subframe. In the PDCCH, downlink control information (information used for control of communication, which includes information formats such as downlink assignment (also referred to as downlink assignment) and uplink grant (Uplink grant)). Downlink Control Information (DCI) signal is allocated.

  The downlink assignment includes information indicating a modulation scheme for PDSCH, information indicating a coding scheme, information indicating radio resource allocation, information on HARQ (Hybrid Automatic Repeat Request), a TPC command, and the like. The uplink grant includes information indicating a modulation scheme for PUSCH, information indicating a coding scheme, information indicating radio resource allocation, information regarding HARQ, a TPC command, and the like. Note that HARQ is, for example, that the mobile station device 1 (base station device 3) transmits data information decoding success / failure (Acknowledgement / Negative Acknowledgement: ACK / NACK) to the base station device 3 (mobile station device 1). When the mobile station apparatus 1 (base station apparatus 3) cannot decode data information due to an error (NACK), the base station apparatus 3 (mobile station apparatus 1) retransmits the signal, and the mobile station apparatus 1 (base station apparatus 3) This is a technique for performing a decoding process on a combined signal of a signal received again and a signal already received.

  Next, PDSCH will be described. The PDSCH is arranged in an OFDM symbol (region not hatched in FIG. 2) other than the OFDM symbol in which the PDCCH of the subframe is arranged. In the PDSCH, data information (transport block) signals are arranged. PDSCH radio resources are allocated using downlink assignment. The PDSCH radio resources are arranged in the same downlink subframe as the PDCCH including the downlink assignment used for the PDSCH assignment in the time domain, and the downlink used for the PDSCH assignment in the frequency domain. It is arranged on the same downlink component carrier as that of the PDCCH including the link assignment and on a different downlink component carrier.

  In the PDCCH, information indicating whether the downlink assignment corresponds to the PDSCH transmitted on which downlink component carrier or the uplink component corresponding to the PUSCH transmitted on the uplink component carrier (hereinafter, referred to as a PSCH). "Referred to as a carrier indicator"). If the downlink assignment does not include a carrier indicator, the downlink assignment corresponds to the PDSCH of the same downlink component carrier from which the downlink assignment was transmitted. When the carrier grant is not included in the uplink grant, the uplink grant corresponds to the PUSCH of the uplink component carrier linked to the same downlink component carrier to which the uplink grant is transmitted. The downlink reference signal is not shown in FIG. 2 for simplicity of explanation, but the downlink reference signal is distributed and arranged in the frequency domain and the time domain.

  Hereinafter, the PDCCH will be described in more detail. The PDCCH is arranged in one or more control channel elements (Control Channel Element: CCE). The control channel element is composed of a plurality of downlink resource elements distributed in the frequency domain and the time domain within the region where the PDCCH is arranged (the region hatched with the left oblique line in FIG. 3). In addition, a common search area (Common Search Space) and a mobile station apparatus specific search area (User Equipment specific-Search Space) are configured from a plurality of control channel elements.

  FIG. 4 is a schematic diagram showing an example of the search area of the present invention. In FIG. 4, the horizontal axis is a number for identifying a control channel element. In FIG. 4, the unit surrounded by a thick line is a candidate (hereinafter referred to as a “PDCCH candidate”) in which a PDCCH is configured, which is composed of a plurality of consecutively-numbered control channel elements. The PDCCH candidates hatched with diagonal lines in FIG. 4 are PDCCH candidates in the mobile station apparatus specific search region, and the PDCCH candidates hatched in gray in FIG. 4 are PDCCH candidates in the common search region.

  The common search area is an area common to a plurality of mobile station apparatuses 1 and is an area where a PDCCH for a plurality of mobile station apparatuses 1 and / or a PDCCH for a specific mobile station apparatus 1 is arranged. Further, the common search area is composed of predetermined control channel elements. In FIG. 4, the common search area is composed of control channel elements from No. 0 to No. 15. The mobile station apparatus specific search area is an area where a PDCCH for a specific mobile station apparatus 1 is arranged, and is an area configured for each mobile station apparatus 1.

  The common search area and the mobile station apparatus specific search area are configured as different common search areas and mobile station apparatus specific search areas for each control channel element constituting the PDCCH candidate. In FIG. 4, a PDCCH candidate composed of one control channel element, a PDCCH candidate composed of two control channel elements, a PDCCH candidate composed of four control channel elements, and eight control channel elements There are four different mobile station apparatus specific search areas for each PDCCH candidate to be performed, and two common search areas different for each PDCCH candidate composed of four control channel elements and PDCCH candidate composed of eight control channel elements There is.

  A part of the control channel elements or a part or all of the PDCCH candidates constituting the common search area and the mobile station apparatus specific search area may overlap, or a part or all of different common search areas may overlap. Alternatively, some or all of the different mobile station apparatus specific search areas for the same mobile station apparatus 1 may overlap, or some or all of the mobile station apparatus specific search areas for different mobile station apparatuses 1 may overlap. Good.

  The base station apparatus 3 configures a common search area for each downlink component carrier. Further, the base station apparatus 3 may allocate one or a plurality of downlink component carriers for monitoring the common search area for each mobile station apparatus 1 and notify the allocated downlink component carriers to the mobile station apparatus. The base station device 3 may assign one or more downlink component carriers constituting the mobile station device specific search area to each mobile station device and notify the mobile station device of the assigned downlink component carrier. Good.

  A plurality of formats are prepared for downlink control information such as downlink assignment and uplink grant. The format of the downlink control information is called a DCI format (DCI format). For example, the DCI format of the uplink grant is DCI format 0 used when the mobile station apparatus 1 transmits PUSCH through one transmission antenna port, and the mobile station apparatus 1 transmits PUSCH to MIMO (Multiple Input Multiple Output) SM (Spatial Multiplexing). The DCI format 0A and the like used for transmission are prepared.

  Also, the DCI format of the downlink grant is the number of bits than the DCI format 1 and the DCI format used when the base station apparatus 3 transmits PDSCH using one transmission antenna port or a plurality of transmission antenna ports using the transmission diversity method. DCI format 1A (a DCI format including information related to one transport block) and a DCI format 1C having a smaller number of bits than the DCI format 1A used for radio resource allocation such as paging information, and the base station apparatus uses PDSCH. DCI format 2 (a DCI format including information related to one or a plurality of transport blocks) used when transmitting is transmitted using MIMO SM. The number of bits in DCI format 1, DCI format 1A, DCI format 1C, and DCI format 2 varies depending on the number of physical resource blocks included in the downlink component carrier corresponding to each DCI format, and the number of bits in DCI format 0 and DCI format 0A. Varies depending on the number of physical resource blocks included in the uplink component carrier corresponding to each DCI format.

  In DCI format 0 and DCI format 1A, by inserting bits into the smaller number of bits, the sizes of the two DCI formats are made the same, and a flag for identifying the format is included. The one in which bits are inserted to make the bit sizes of DCI format 0 and DCI format 1A the same is called DCI format 0 / 1A.

  The DCI format 1C can be arranged only in the common search area. DCI format 0 / 1A that does not include a carrier indicator can be arranged in both the common search area and the mobile station apparatus specific search area. The DCI format 0 / 1A including the carrier indicator can be arranged only in the mobile station apparatus specific search area. DCI format 0A and DCI format 2 can be arranged only in the mobile station apparatus specific search region both when the carrier indicator is included and when it is not included.

  FIG. 5 is a schematic diagram illustrating a downlink control information encoding method and arrangement method according to the present invention. First, the base station apparatus 3 adds, to the downlink control information, a sequence obtained by scrambling a cyclic redundancy check (CRC) code generated based on downlink control information with RNTI (Radio Network Temporary Identity). . The mobile station apparatus 1 changes the interpretation of the downlink control information depending on which RNTI the cyclic redundancy check code is scrambled. For example, if the cyclic redundancy check code is scrambled by the C-RNTI (Cell-Radio Network Temporary Identity) assigned by the mobile station apparatus 1 from the base station apparatus 3, the downlink control information is addressed to the mobile station apparatus 1 It is determined that the radio resource is indicated. Hereinafter, the addition of a cyclic redundancy check code scrambled with RNTI to downlink control information is simply expressed as RNTI included in downlink control information or RNTI included in PDCCH.

  Next, the base station apparatus 3 encodes the downlink control information in accordance with the number of bits of the PDCCH candidate in which the encoded downlink control information is arranged, and arranges it in the PDCCH candidate in the common search area or the mobile station apparatus specific search area. To do. The base station apparatus 3 performs the same encoding for the DCI format having the same number of bits, and performs the different encoding for the DCI format having a different number of bits. That is, since the encoding method applied to the DCI format by the base station apparatus 3 differs depending on the number of bits of the DCI format (or also referred to as “payload size”), the mobile station apparatus 1 depends on the number of bits of the DCI format. The method of decoding the DCI format is different. Therefore, the mobile station apparatus 1 can determine the type of the DCI format from the number of bits in the DCI format or the difference in the decoding method. When the number of bits of the DCI format is the same, the DCI format includes information for determining the type of the DCI format, or a cyclic redundancy check code scrambled with the RNTI corresponding to the type of the DCI format is added. Is used to enable the mobile station apparatus 1 to determine the type of the DCI format.

  The mobile station apparatus 1 decodes all candidates in which the PDCCH is arranged in the common search area and the mobile station apparatus specific search area, further descrambles a sequence obtained by scrambling the cyclic redundancy check code with the RNTI, When it is detected that there is no error in the descrambled cyclic redundancy check code, it is determined that acquisition of the PDCCH is successful. This process is called blind decoding.

  The base station apparatus 3 includes PDCCH including P-RNTI (Paging-Radio Network Temporary Identity) used for scheduling paging information and system information update information, and SI-RNTI (System Information-) used for scheduling system information. A PDCCH including a Radio Network Temporary Identity (PDCCH) and a PDCCH including an RA-RNTI (Random Access-Radio Network Temporary Identity) used for scheduling of a random access response are arranged in the common search area, and the mobile station apparatus 1 is configured in the common search area. The PDCCH including P-RNTI, the PDCCH including SI-RNTI, and the PDCCH including RA-RNTI are blind-decoded. P-RNTI, SI-RNTI, and RA-RNTI are included only in DCI format 1C and DCI format 1A.

  The base station device 3 arranges the PDCCH including the C-RNTI in the common search region or the mobile station device specific search region of the mobile station device 1 to which the C-RNTI is assigned. PDCCH including C-RNTI is blind-decoded in the eigensearch area. Specifically, the base station apparatus arranges DCI format 0 / 1A including C-RNTI and not including a carrier indicator in a common search area or a mobile station apparatus specific search area of mobile station apparatus 1 to which C-RNTI is allocated, and C -DCI format 0 / 1A including RNTI and including a carrier indicator, DCI format 0A including C-RNTI and DCI format 2 including C-RNTI in the mobile station apparatus specific search area of mobile station apparatus 1 to which C-RNTI is allocated Deploy.

  The base station apparatus 3 determines whether the mobile station apparatus 1 performs blind decoding on the type of DCI format that the mobile station apparatus 1 performs blind decoding, and whether the carrier indicator is included in the DCI format arranged in the mobile station apparatus specific search area. Instructions can be given for each component carrier.

  FIG. 6 is a flowchart showing an example of operations of the mobile station device 1 and the base station device 3 of the present invention. FIG. 6 is a flowchart for explaining a method for calculating the number of bits in the DCI format. The mobile station apparatus 1 and the base station apparatus 3 calculate the number of bits in the DCI format by the same method. When the processing is started, the mobile station apparatus 1 and the base station apparatus 3 include the number of physical resource blocks included in the downlink component carrier, the number of physical resource blocks included in the uplink component carrier, and the carrier indicator in the DCI format. Based on the above, the number of bits of the field indicating the allocation of the radio resource of the DCI format is calculated, and the number of bits of the DCI format indicating the allocation of the radio resource of the PDSCH or PUSCH is calculated. (Step S100).

  The mobile station apparatus 1 and the base station apparatus 3 determine whether the DCI format is arranged in an area where the common search area and the mobile station apparatus specific search area overlap (step S101). Note that the common search area and the mobile station apparatus specific search area overlap each other as indicated by PDCCHs composed of the same control channel element numbers as PDCCH candidates composed of control channel elements 8 to 15 in FIG. The candidate is included in both the common search area and the mobile station apparatus specific search area. In step S101, when the DCI format is not arranged in an area where the common search area and the mobile station apparatus specific search area overlap, the mobile station apparatus 1 and the base station apparatus 3 perform processing related to the calculation of the number of bits of the DCI format. finish.

  In step S101, when the DCI format is arranged in an area where the common search area and the mobile station apparatus specific search area overlap, the mobile station apparatus 1 and the base station apparatus 3 each of the bits of the DCI format calculated in step S100. The numbers are compared (step S102). In step S102, when the numbers of bits of the DCI formats calculated in step S100 are all different, the mobile station apparatus 1 and the base station apparatus 3 end the processing related to the calculation of the number of bits of the DCI format. That is, even in the same DCI format, whether the bit is inserted is switched depending on whether the common search area and the mobile station apparatus specific search area are arranged in the overlapping area or the non-overlapping area.

  In step S102, when the number of bits of each DCI format calculated in step S100 is the same and there is a DCI format arranged in an area where the common search area and the mobile station apparatus specific search area overlap, the mobile station apparatus 1 and the base station The apparatus 3 inserts 1 bit into one of the DCI formats (step S103), returns to step S102, and compares again the number of bits of the DCI format with the inserted bits and the other DCI format. In step S103, it is determined in advance to which DCI format the bit is inserted. That is, the priority order of the DCI format into which bits are inserted is determined.

  For example, the number of bits of DCI format 0 / 1A not including the carrier indicator calculated by mobile station device 1 and base station device 3 in step S100 is 40 bits, and the number of bits of DCI format 0 / 1A including the carrier indicator is 40 bits. Suppose that the number of bits of DCI format 2 including the carrier indicator is 40 bits. The downlink component carrier and the uplink component corresponding to the DCI format 0 / 1A not including the carrier indicator are the physical resource blocks included in the downlink component carrier and the uplink component carrier corresponding to the DCI format 0 / 1A including the carrier indicator. When there are fewer physical resource blocks included in the carrier, the number of bits of DCI format 0 / 1A (number of information bits) not including the carrier indicator and the number of bits (information number of bits) of DCI format 0 / 1A including the carrier indicator are May be the same.

  In step S103, bits are inserted in the DCI format 0 / 1A arranged in the common search area, the DCI format 0 / 1A arranged in the mobile station apparatus specific search area, and the DCI format 2 arranged in the mobile station apparatus specific search area. The mobile station apparatus 1 and the base station apparatus 3 store this order. If the DCI format is not arranged in the area where the common search area and the mobile station apparatus specific search area overlap in step S101, the mobile station apparatus 1 and the base station apparatus 3 determine the number of bits of each DCI format calculated in step S100. Use as is.

  In step S102, the number of bits of the DCI format 0 / 1A not including the carrier indicator arranged in the common search area and the DCI format 0 / 1A including the carrier indicator arranged in the mobile station apparatus specific search area are 40 bits, which are the same. The mobile station apparatus 1 and the base station apparatus 3 insert 1 bit into the DCI format 0 / 1A including the carrier indicator to be arranged in the mobile station apparatus specific search area, set the number of bits to 41 bits, and return to step S103.

  Returning to step S103, the number of bits of DCI format 0 / 1A including the carrier indicator to be arranged in the common search area and DCI format 2 to be arranged in the mobile station apparatus specific search area are the same at 40 bits. The base station apparatus 3 inserts 1 bit into the DCI format 2 arranged in the mobile station apparatus specific search area, sets the number of bits to 41 bits, and returns to step S103.

  Returning to step S103, the number of bits of each of the DCI format 0 / 1A including the carrier indicator arranged in the mobile station apparatus specific search area and the DCI format 2 including the carrier indicator arranged in the mobile station apparatus specific search area is 41 bits. Since it is the same, mobile station apparatus 1 and base station apparatus 3 insert 1 bit into DCI format 2 including the carrier indicator to be arranged in the mobile station apparatus specific search area, set the number of bits to 42 bits, and return to step S103.

  After the above steps, the number of bits of DCI format 0 / 1A not including the carrier indicator is 40 bits (second payload size), the number of bits of DCI format 0 / 1A including the carrier indicator is 41 bits (first payload size), Since the number of bits of the DCI format 2 including the carrier indicator becomes 42 bits (first payload size) and the number of bits of each DCI format is not the same, the mobile station device 1 and the base station device 3 have the number of bits of the DCI format. The processing related to the calculation of is terminated.

  In this way, the common search is performed by inserting bits in the DCI format including the carrier indicator in the DCI format and / or the DCI format including the carrier indicator in preference to the DCI format allocated in the common search region. By preventing bits from being inserted into the DCI format arranged in the area, the number of bits of the DCI format arranged in the common search area can be made the same between mobile station apparatuses.

  In addition, when the values indicated by the DCI format 0 / 1A including the carrier indicator arranged in the mobile station apparatus specific search area and the DCI format 2 including the carrier indicator arranged in the mobile station apparatus specific search area are different from each other, Since the DCI format can be identified from the value indicated by the carrier indicator, bits are not inserted into the DCI format 2 including the carrier indicator arranged in the mobile station apparatus specific search region. That is, the mobile station apparatus 1 and the base station apparatus 3 determine whether or not to insert bits depending on whether the values indicated by the carrier indicators included in the two DCI formats having the same number of bits are the same or different.

  The base station apparatus 3 generates a DCI format having the number of bits of the DCI format calculated according to the flowchart of FIG. 6, encodes and modulates, and transmits the PDCCH. The mobile station apparatus 1 blind-decodes the DCI format of the number of bits of the DCI format calculated according to the flowchart of FIG. The mobile station apparatus 1 and the base station apparatus 3 may calculate the number of bits of the DCI format for each subframe according to the flowchart of FIG. 6, or the number of bits calculated in advance for various combinations of DCI formats. May be stored.

  In the flowchart of FIG. 6, step S101 may be omitted. By omitting step S101, the DCI format arranged in the common search area and the DCI arranged in the mobile station apparatus specific search area regardless of whether the common search area and the mobile station apparatus specific search area overlap. If the number of bits of the format is the same, the bits are inserted into the DCI format arranged in the mobile station device specific search area. As a result, unnecessary bits are also inserted in the DCI format arranged in the mobile station device specific search region that does not overlap with the common search region, but the device configurations of the mobile station device 1 and the base station device 3 are simplified. Can be

  FIG. 7 is a schematic block diagram showing the configuration of the base station apparatus 3 of the present invention. As illustrated, the base station apparatus 3 includes an upper layer processing unit 101, a control unit 103, a receiving unit 105, a transmitting unit 107, a channel measuring unit 109, and a transmission / reception antenna 111. The upper layer processing unit 101 includes a radio resource control unit 1011, a scheduling unit 1013, and a downlink control information generation unit 1015. The reception unit 105 includes a decoding unit 1051, a demodulation unit 1053, a demultiplexing unit 1055, and a wireless reception unit 1057. The transmission unit 107 includes an encoding unit 1071, a modulation unit 1073, a multiplexing unit 1075, a radio transmission unit 1077, and a downlink reference signal generation unit 1079.

  The upper layer processing unit 101 performs processing of a packet data convergence protocol (PDCP) layer, a radio link control (Radio Link Control: RLC) layer, and a radio resource control (Radio Resource Control: RRC) layer. Further, the upper layer processing unit 101 generates control information for the scheduling unit 1013 and the like to control the receiving unit 105 and the transmitting unit 107 based on the scheduling result and outputs the control information to the control unit 103. The radio resource control unit 1011 included in the upper layer processing unit 101 generates information acquired on the downlink PDSCH or acquires it from the upper node, and outputs the information to the transmission unit 107. Further, the radio resource control unit 1011 manages various setting information of each mobile station apparatus 1. For example, the radio resource control unit 1011 performs RNTI management such as assigning C-RNTI to the mobile station apparatus 1.

  The scheduling unit 1013 included in the higher layer processing unit 101 includes uplink control information (ACK / NACK, channel quality information, scheduling request) notified from the mobile station device 1 through the PUCCH, and a buffer notified from the mobile station device 1. Based on the situation and various setting information of each mobile station apparatus 1 set by the radio resource control unit 1011, scheduling such as radio resource allocation, coding scheme setting, modulation scheme setting, and the like is performed. The scheduling unit 1013 allocates a radio resource in which a specific mobile station apparatus 1 places a PUSCH from among uplink radio resources. The scheduling unit 1013 allocates radio resources with good channel quality based on the uplink channel measurement result input from the channel measurement unit 109 when allocating radio resources for arranging the PUSCH to a specific mobile station apparatus 1. Assign with priority.

  Also, the scheduling unit 1013 determines a radio resource for arranging the PDSCH from downlink radio resources. The scheduling unit 1013 outputs control information to the downlink control information generation unit 1015 so as to generate downlink control information indicating the radio resource allocation. In addition, the scheduling unit 1013 assigns PDCCH candidates in which the downlink control information generated by the downlink control information generation unit 1015 from the common search region or the mobile station device specific search region to the common search region or the mobile station device specific search region. Assign from the list. The scheduling unit 1013 selects a PDCCH candidate in which downlink control information including C-RNTI is arranged from the mobile station apparatus specific search area and the common search area of the mobile station apparatus 1 to which the C-RNTI is allocated.

  A downlink control information generation unit 1015 included in the higher layer processing unit 101 generates downlink control information indicating uplink or downlink radio resource allocation based on the control information input from the scheduling unit 1013. The downlink control information generation unit 1015 inserts bits into the downlink control information according to the flowchart of FIG. Next, the downlink control information generation unit 1015 generates a cyclic redundancy check code from the generated downlink control information, scrambles the generated cyclic redundancy check code with RNTI, and adds it to the downlink control information. The downlink control information generation unit 1015 scrambles the cyclic redundancy check code with the C-RNTI assigned to the mobile station apparatus 1 when the downlink control information indicates assignment of radio resources to the specific mobile station apparatus 1. To do.

  The control unit 103 generates a control signal for controlling the reception unit 105 and the transmission unit 107 based on the control information from the higher layer processing unit 101. The control unit 103 outputs the generated control signal to the reception unit 105 and the transmission unit 107 to control the reception unit 105 and the transmission unit 107.

  The receiving unit 105 separates, demodulates, and decodes the received signal received from the mobile station apparatus 1 via the transmission / reception antenna 111 according to the control signal input from the control unit 103, and outputs the decoded information to the upper layer processing unit 101. To do. The radio reception unit 1057 converts the uplink signal received via the transmission / reception antenna 111 to an intermediate frequency (down covert), removes unnecessary frequency components, and maintains the signal level appropriately. Then, the amplification level is controlled, quadrature demodulation is performed based on the in-phase component and the quadrature component of the received signal, and the quadrature demodulated analog signal is converted into a digital signal. The wireless reception unit 1057 removes a portion corresponding to a guard interval (GI) from the converted digital signal. Radio receiving section 1057 performs fast Fourier transform (FFT) on the signal from which the guard interval is removed, extracts a frequency domain signal, and outputs the signal to demultiplexing section 1055.

  The demultiplexing unit 1055 demultiplexes the signal input from the radio receiving unit 1057 into signals such as PUCCH, PUSCH, and uplink reference signal. Note that this separation is performed based on radio resource allocation information that is determined in advance by the scheduling unit 1013 by the base station device 3 and notified to each mobile station device 1. In addition, demultiplexing section 1055 compensates for the propagation paths of PUCCH and PUSCH based on the propagation path estimation value input from channel measurement section 109. Further, the demultiplexing unit 1055 outputs the separated uplink reference signal to the channel measurement unit 109.

  The demodulator 1053 performs inverse discrete Fourier transform (IDFT) on the PUSCH, acquires modulation symbols, and performs binary phase shift keying (BPSK) on each of the modulation symbols of the PUCCH and the PUSCH. ) 4 phase quadrature phase shift keying (QPSK), 16 quadrature amplitude modulation (16QAM), 64 quadrature amplitude modulation (64QAM), or the like, or The base station apparatus 3 demodulates the received signal using the modulation scheme notified in advance to each mobile station apparatus 1 using downlink control information.

  The decoding unit 1051 encodes the demodulated PUCCH and PUSCH encoded bits in a predetermined encoding scheme, or a code that the base station apparatus 3 notifies the mobile station apparatus 1 in advance with an uplink grant. The decoding is performed at the conversion rate, and the decoded data information and the uplink control information are output to the upper layer processing unit 101. Channel measurement section 109 measures an estimated value of the propagation path, channel quality, and the like from the uplink reference signal input from demultiplexing section 1055, and outputs the result to demultiplexing section 1055 and higher layer processing section 101.

  The transmission unit 107 generates a downlink reference signal according to the control signal input from the control unit 103, encodes and modulates data information and downlink control information input from the higher layer processing unit 101, PDCCH, The PDSCH and the downlink reference signal are multiplexed, and the signal is transmitted to the mobile station apparatus 1 via the transmission / reception antenna 111.

  The encoding unit 1071 determines the downlink control information and data information input from the higher layer processing unit 101 in advance, such as turbo encoding, convolutional encoding, and block encoding, or is determined by the scheduling unit 1013. Encoding is performed. Modulation section 1073 modulates the coded bits input from coding section 1071 with a modulation scheme determined in advance by QPSK, 16QAM, 64QAM, or the like, or determined by scheduling section 1013. The downlink reference signal generation unit 1079 uses, as a downlink reference signal, a sequence known by the mobile station device 1 that is obtained by a predetermined rule based on a cell identifier (Cell ID) for identifying the base station device 3 or the like. Generate. The multiplexing unit 1075 multiplexes each modulated channel and the generated downlink reference signal.

  Radio transmission section 1077 performs inverse fast Fourier transform (IFFT) on the multiplexed modulation symbol, performs modulation in the OFDM scheme, adds a guard interval to the OFDM symbol that has been OFDM-modulated, and performs baseband digital Generate a signal, convert the baseband digital signal to an analog signal, generate in-phase and quadrature components of the intermediate frequency from the analog signal, remove excess frequency components for the intermediate frequency band, and increase the signal of the intermediate frequency The signal is converted into a frequency signal (up-converted: up-converted), an extra frequency component is removed, the power is amplified, and the signal is output to the transmission / reception antenna 111 and transmitted.

  FIG. 8 is a schematic block diagram showing the configuration of the mobile station apparatus 1 of the present invention. As illustrated, the mobile station apparatus 1 includes an upper layer processing unit 201, a control unit 203, a receiving unit 205, a transmitting unit 207, a channel measuring unit 209, and a transmission / reception antenna 211. The upper layer processing unit 201 includes a radio resource control unit 2011, a scheduling unit 2013, and a blind decoding control unit 2015. The reception unit 205 includes a decoding unit 2051, a demodulation unit 2053, a demultiplexing unit 2055, and a wireless reception unit 2057. The transmission unit 207 includes an encoding unit 2071, a modulation unit 2073, a multiplexing unit 2075, a radio transmission unit 2077, and an uplink reference signal generation unit 2079.

  The upper layer processing unit 201 outputs uplink data information generated by a user operation or the like to the transmission unit 207. The upper layer processing unit 201 performs processing of the packet data integration protocol layer, the radio link control layer, and the radio resource control layer. Further, the upper layer processing unit 201 generates control information for controlling the receiving unit 205 and the transmitting unit 207 based on the downlink control information and outputs the control information to the control unit 203. The radio resource control unit 2011 included in the upper layer processing unit 201 manages various setting information of the own device. For example, the radio resource control unit 2011 manages RNTI such as C-RNTI. Also, the radio resource control unit 2011 generates information to be arranged in each uplink channel and outputs the information to the transmission unit 207.

  The blind decoding control unit 2015 included in the higher layer processing unit 201 performs blind decoding on the downlink control information in the DCI format to be detected by the mobile station apparatus 1 in the common search area and / or the mobile station apparatus specific search area. Control information for controlling the receiving unit 205 is generated and output to the control unit 203. The blind decoding control unit 2015 generates control information for controlling the receiving unit 205 to blind-decode the PDCCH including the C-RNTI in the common search region and the mobile station apparatus specific search region, and sends the control information to the control unit 203. Output. Also, the blind decoding control unit 2015 calculates the number of bits of the downlink control information according to the flowchart of FIG. 6 for the number of bits in the DCI format for performing blind decoding.

  The scheduling unit 2013 included in the higher layer processing unit 201 is managed by the radio resource control unit 2011 set by the downlink control information notified by the PDCCH from the base station apparatus 3 and the radio resource control signal notified by the PDSCH. Based on various setting information of the apparatus, control information is generated to control the receiving unit 205 and the transmitting unit 207, and is output to the control unit 203. The scheduling unit 2013 controls the receiving unit 205 to demultiplex, demodulate, and decode the PDSCH based on the downlink assignment input from the receiving unit 205, and to the uplink grant input from the receiving unit 205. Based on this, control information for controlling transmission section 207 so as to perform coding, modulation, and multiplexing of PUSCH is generated and output to control section 203.

  The control unit 203 generates a control signal for controlling the reception unit 205 and the transmission unit 207 based on the control information from the higher layer processing unit 201. The control unit 203 outputs the generated control signal to the reception unit 205 and the transmission unit 207 to control the reception unit 205 and the transmission unit 207. The receiving unit 205 separates, demodulates, and decodes the received signal received from the base station apparatus 3 via the transmission / reception antenna 211 according to the control signal input from the control unit 203, and sends the decoded information to the upper layer processing unit 201. Output.

  The radio reception unit 2057 converts a downlink signal received via the transmission / reception antenna 211 into an intermediate frequency (down-conversion), removes unnecessary frequency components, and an amplification level so that the signal level is appropriately maintained. , And quadrature demodulation based on the in-phase and quadrature components of the received signal, and converting the quadrature demodulated analog signal into a digital signal. The radio reception unit 2057 removes a portion corresponding to the guard interval from the converted digital signal, performs fast Fourier transform on the signal from which the guard interval is removed, and extracts a frequency domain signal.

  The demultiplexing unit 2055 separates the extracted signal into a PDCCH, a PDSCH, and a downlink reference signal. This separation is performed based on radio resource allocation information notified by the downlink control information. Further, demultiplexing section 2055 compensates for the propagation paths of PDCCH and PDSCH from the estimated propagation path values input from channel measurement section 209. Also, the demultiplexing unit 2055 outputs the separated downlink reference signal to the channel measurement unit 209.

  Demodulation section 2053 demodulates the QPSK modulation scheme for PDCCH and outputs the result to decoding section 2051. The decoding unit 2051 attempts blind decoding of the PDCCH, and when the blind decoding is successful, the decoding unit 2051 outputs the decoded downlink control information and the RNTI included in the downlink control information to the higher layer processing unit 201. Demodulation section 2053 demodulates the PDSCH according to the modulation scheme notified by downlink control information such as QPSK, 16QAM, and 64QAM, and outputs the result to decoding section 2051. The decoding unit 2051 performs decoding on the coding rate notified by the downlink control information, and outputs the decoded data information to the higher layer processing unit 201.

  The channel measurement unit 209 measures the downlink path loss from the downlink reference signal input from the demultiplexing unit 2055, and outputs the measured path loss to the higher layer processing unit 201. Further, channel measurement section 209 calculates an estimated value of the downlink propagation path from the downlink reference signal, and outputs it to demultiplexing section 2055.

  The transmission unit 207 generates an uplink reference signal according to the control signal input from the control unit 203, encodes and modulates data information input from the higher layer processing unit 201, and generates PUCCH, PUSCH, and the generated uplink The link reference signal is multiplexed and transmitted to the base station apparatus 3 via the transmission / reception antenna 211. The encoding unit 2071 encodes the uplink control information input from the higher layer processing unit 201, such as convolutional encoding and block encoding, and sets the data information to the encoding rate notified by the downlink control information. Based on this, turbo coding is performed. The modulation unit 2073 modulates the coded bits input from the coding unit 2071 using a modulation method notified by downlink control information such as BPSK, QPSK, 16QAM, 64QAM, or a modulation method predetermined for each channel. .

  The uplink reference signal generation unit 2079 is a sequence that is known by the base station device 3 and is determined by a predetermined rule based on a cell identifier for identifying the base station device 3, a bandwidth for arranging the uplink reference signal, and the like. Is generated. The multiplexing unit 2075 rearranges the PUSCH modulation symbols in parallel according to the control signal input from the control unit 203, and then performs discrete Fourier transform (DFT) to generate the PUCCH and PUSCH signals and the generated uplink reference Multiplex the signal.

  The wireless transmission unit 2077 performs inverse fast Fourier transform on the multiplexed signal, performs SC-FDMA modulation, adds a guard interval to the SC-FDMA-modulated SC-FDMA symbol, and generates a baseband digital signal Convert the baseband digital signal to an analog signal, generate in-phase and quadrature components of the intermediate frequency from the analog signal, remove excess frequency components for the intermediate frequency band, and convert the intermediate-frequency signal to a high-frequency signal Are converted (up-converted) to remove excess frequency components, power-amplified, and output to the transmission / reception antenna 211 for transmission.

  As described above, according to the present invention, in a radio communication system that transmits a plurality of mobile station apparatuses and downlink control information to the plurality of mobile station apparatuses by PDCCH, the base station apparatus 3 includes a DCI format that does not include a carrier indicator. If the number of bits of each DCI format including the carrier indicator is the same, 1 bit is inserted into the DCI format including the carrier indicator, and the mobile station apparatus 1 decodes that 1 bit is inserted into the DCI format including the carrier indicator. To do.

  According to the present invention, the DCI format that does not include the carrier indicator and the DCI format that includes the carrier indicator may be the same DCI format. Further, according to the present invention, the base station apparatus 3 performs the mobile station apparatus specific search when the number of bits of the DCI format arranged in the common search area and the DCI format arranged in the mobile station apparatus specific search area are the same. One bit is inserted into the DCI format arranged in the area, and the mobile station apparatus 1 decodes that one bit is inserted into the DCI format arranged in the mobile station apparatus specific search area.

  Further, according to the present invention, only when the DCI format is arranged in an area where the common search area and the mobile station apparatus specific search area overlap, the base station apparatus 3 inserts a bit into the DCI format, and the mobile station apparatus 1 Is decoded assuming that bits are inserted in the DCI format. Thereby, the mobile station apparatus 1 can identify the type of the DCI format in an area where the common search area and the mobile station apparatus specific search area overlap from the difference in the number of bits of the DCI format, that is, the decoding method.

(Second Embodiment)
Hereinafter, a second embodiment of the present invention will be described in detail with reference to the drawings.

  In the second embodiment of the present invention, the common search area and the mobile station apparatus specific search area overlap, and the number of bits of the DCI format arranged in the common search area and the bits of the DCI format arranged in the mobile station apparatus specific search area When the numbers are the same, the base station apparatus 3 does not arrange the DCI format arranged in the mobile station apparatus specific search area in the area, and the mobile station apparatus 1 blind-decodes only the DCI format arranged in the common search area in the area. Coding.

  For example, when 40-bit DCI format 0 / 1A is arranged in the common search area and 40-bit DCI format 2 and 41-bit DCI format 0A are arranged in the mobile station apparatus specific search area, the base station apparatus 3 is common. DCI format 0 / 1A and DCI format 0A are arranged in an area where the search area and the mobile station apparatus search area overlap, and DCI format 2 having the same number of bits as DCI format 0 / 1A arranged in the common search area is arranged. The mobile station apparatus 1 blindly decodes the DCI format 0 / 1A and the DCI format 0A in the area where the common search area and the mobile station apparatus search area overlap, and the DCI format 0 / Blind decoding of DCI format 2 with the same number of bits as 1A There.

  When the radio communication system according to the present embodiment and the radio communication system according to the first embodiment are compared, the upper layer processing unit 101 of the base station device 3 and the upper layer processing unit 201 of the mobile station device 1 are different. However, since the configuration and functions of other components are the same as those in the first embodiment, description of the same functions as those in the first embodiment is omitted.

  The downlink control information generation unit 1015 of the higher layer processing unit 101 of the base station apparatus 1 according to the second embodiment does not insert bits into the DCI format based on the flowchart of FIG. In addition, the scheduling unit of the upper layer processing unit 101 performs mobile station apparatus specific search having the same number of bits as the number of bits of the DCI format arranged in the common search area in an area where the common search area and the mobile station apparatus specific search area overlap. The transmission unit 107 is controlled via the control unit 103 so as not to arrange the DCI format to be arranged in the area.

  The blind decoding control unit 2015 of the upper layer processing unit 201 of the mobile station apparatus 3 according to the second embodiment does not calculate the number of bits on the basis of the flowchart of FIG. 6 assuming that bits are inserted into the DCI format. Also, the blind decoding control unit 2015 is arranged in the mobile station apparatus specific search area having the same number of bits as the DCI format arranged in the common search area in the area where the common search area and the mobile station apparatus specific search area overlap. The receiving unit 207 is controlled via the control unit 203 so that coding is not performed using the DCI format blind.

  Thereby, the mobile station apparatus 1 can identify the types of DCI formats arranged in the common search area and the mobile station apparatus specific search area.

(Third embodiment)
Hereinafter, the third embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 9 is a schematic diagram illustrating an example of a search area according to the third embodiment of the present invention. In the third embodiment of the present invention, the mobile station apparatus 1 and the base station apparatus 3 are hatched with PDCCH candidates (lines on the grid in FIG. 9) that are configured by control channel elements 8 to 15 in FIG. When the common search area and the mobile station apparatus specific search area overlap (T100), the PDCCH candidates constituting the mobile station apparatus specific search area are searched for the mobile station apparatus specific search overlapping the common search area. The PDCCH candidate in the area is changed to a PDCCH candidate composed of control channel elements 24 to 31 that are not included in the common search area (T101).

  When the radio communication system according to the present embodiment and the radio communication system according to the first embodiment are compared, the upper layer processing unit 101 of the base station device 3 and the upper layer processing unit 201 of the mobile station device 1 are different. However, since the configuration and functions of other components are the same as those in the first embodiment, description of the same functions as those in the first embodiment is omitted.

  The downlink control information generation unit 1015 of the higher layer processing unit 101 of the base station apparatus 1 according to the third embodiment does not insert bits into the DCI format based on the flowchart of FIG. In addition, when the common search region and the mobile station device specific search region overlap, the scheduling unit of the upper layer processing unit 101 determines the PDCCH candidates constituting the mobile station device specific search region specific to the mobile station device overlapping the common search region. The PDCCH candidate in the search area is changed to a PDCCH candidate not included in the common search area.

  The blind decoding control unit 2015 of the higher layer processing unit 201 of the mobile station apparatus 3 of the third embodiment does not calculate the number of bits on the basis of the flowchart of FIG. 6 assuming that bits are inserted in the DCI format. In addition, when the common search region and the mobile station device specific search region overlap, the blind decoding control unit 2015 sets the PDCCH candidate constituting the mobile station device specific search region to the mobile station device specific search region that overlaps the common search region. PDCCH candidates are changed to PDCCH candidates not included in the common search region.

  As a result, the mobile station apparatus 1 identifies the types of DCI formats arranged in the common search area and the mobile station apparatus specific search area without inserting bits into the DCI format as in the first embodiment. Therefore, the coding rate of the PDCCH, DCI, or DCI format can be kept low. Further, as in the second embodiment, PDCCH candidates that can arrange the DCI format arranged in the mobile station apparatus specific search area having the same number of bits as the DCI format arranged in the common search area are not limited. The degree of freedom is maintained.

  Hereinafter, a modification of the third embodiment of the present invention will be described in detail with reference to the drawings.

  In the modification of the third embodiment of the present invention, the mobile station apparatus 1 and the base station apparatus 3 determine PDCCH candidates configured from control channel elements 0 to 15 that constitute the common search area of FIG. The number of control channel elements constituting the PDCCH candidate is not included in the mobile station apparatus specific search areas of 4 and 8, which are the same as the common search area.

  Specifically, the control channel elements and PDCCH candidates that constitute the mobile station apparatus specific search region are input to the hashing function such as the C-RNTI to which the mobile station apparatus 1 is assigned and the number for identifying the subframe. Can be obtained. In the modification of the third embodiment, when determining the mobile station apparatus specific search areas of 4 and 8 having the same number of control channel elements constituting the PDCCH candidate as the common search area, from No. 0 to 15 in FIG. 1 and 2 mobile station apparatus specific search areas in which the number of control channel elements constituting a PDCCH candidate is different from the common search area, the mobile station apparatus specific search areas are determined from control channel elements 16 to 47 excluding the numbers Is determined from all the control channel elements from No. 0 to No. 47 in FIG.

  In the third embodiment, when the mobile station apparatus specific search area is determined from all control channel elements and the common search area and the mobile station apparatus specific search area overlap, the common search area and the mobile station apparatus specific search area are While the mobile station apparatus specific search area is changed so as not to overlap, in the modification of the third embodiment, the control channel that configures the PDCCH candidate so that the common search area and the mobile station apparatus specific search area do not overlap When a mobile station apparatus specific search area having the same number of elements as the common search area is determined, the mobile station apparatus specific search area is determined from the control channel elements excluding the control channel elements used for the common search area. .

  As a result, the mobile station apparatus 1 identifies the types of DCI formats arranged in the common search area and the mobile station apparatus specific search area without inserting bits into the DCI format as in the first embodiment. Therefore, the coding rate of the PDCCH, DCI, or DCI format can be kept low. Further, as in the second embodiment, PDCCH candidates that can arrange the DCI format arranged in the mobile station apparatus specific search area having the same number of bits as the DCI format arranged in the common search area are not limited. The degree of freedom is maintained.

  A program that operates in the base station apparatus 3 and the mobile station apparatus 1 related to the present invention is a program (computer function) that controls a CPU (Central Processing Unit) or the like so as to realize the functions of the above-described embodiments related to the present invention. Program). Information handled by these devices is temporarily stored in RAM (Random Access Memory) during the processing, and then stored in various ROMs such as Flash ROM (Read Only Memory) and HDD (Hard Disk Drive). Reading, correction, and writing are performed by the CPU as necessary.

  In addition, you may make it implement | achieve the mobile station apparatus 1 in the embodiment mentioned above, and a part of base station apparatus 3 with a computer. In that case, the program for realizing the control function may be recorded on a computer-readable recording medium, and the program recorded on the recording medium may be read by the computer system and executed. Here, the “computer system” is a computer system built in the mobile station apparatus 1 or the base station apparatus 3 and includes an OS and hardware such as peripheral devices.

  The “computer-readable recording medium” refers to a storage device such as a flexible medium, a magneto-optical disk, a portable medium such as a ROM and a CD-ROM, and a hard disk incorporated in a computer system. Furthermore, the “computer-readable recording medium” is a medium that dynamically holds a program for a short time, such as a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line, In such a case, a volatile memory inside a computer system serving as a server or a client may be included and a program that holds a program for a certain period of time. The program may be a program for realizing a part of the functions described above, and may be a program capable of realizing the functions described above in combination with a program already recorded in a computer system.

  Moreover, you may implement | achieve part or all of the mobile station apparatus 1 in the embodiment mentioned above and the base station apparatus 3 as LSI which is typically an integrated circuit. Each functional block of the mobile station device 1 and the base station device 3 may be individually chipped, or a part or all of them may be integrated into a chip. Further, the method of circuit integration is not limited to LSI, and may be realized by a dedicated circuit or a general-purpose processor. In addition, when an integrated circuit technology that replaces LSI appears due to progress in semiconductor technology, an integrated circuit based on the technology can also be used.

  (A) The present invention can also take the following aspects. That is, the radio communication system of the present invention is a radio communication system having a mobile station apparatus and a base station apparatus that transmits control information to the mobile station apparatus, and the base station apparatus has a format of the control information. When the number of information bits of the first format including information indicating the component carrier is a predetermined number of bits, the first payload size is determined by inserting at least one bit into the first format, and the first payload size The first format is transmitted to the mobile station apparatus, and the mobile station apparatus performs reception processing of the first format on the assumption that the first format is the first payload size.

  (B) Further, in the wireless communication system of the present invention, the predetermined number of bits is a number of bits of a payload size of a second format which is a format of the control information and does not include information indicating a component carrier.

  (C) In the wireless communication system of the present invention, the first format includes information indicating a component carrier in the second format.

  (D) In the radio communication system of the present invention, the second format is arranged in a common search area, and the first format is arranged in a mobile station apparatus specific search area.

  (E) Also, in the radio communication system of the present invention, the base station device may include a bit in the first format when the first format is arranged in a region where a common search region and a mobile station device specific search region overlap. When the first format is arranged in an area where the common search area and the mobile station apparatus specific search area overlap, the mobile station apparatus performs reception processing assuming that the bit is inserted in the second format. To do.

  (F) In the wireless communication system of the present invention, the first format and the second format are control information transmitted to the same mobile station apparatus.

  (G) Moreover, the radio communication of the present invention is a radio communication system having a mobile station apparatus and a base station apparatus that transmits control information to the mobile station apparatus, and the base station apparatus uses the format of the control information. If the number of bits in the first format arranged in the common search area is the same as the number of bits in the second format arranged in the mobile station device specific search area and the format of the control information, the common search area and the mobile station In the region where the device-specific search regions overlap, only the first format is arranged without arranging the second format, the first format is transmitted, and the mobile station device is in the format of the control information and is in the common search region. The number of bits of the first format to be arranged and the format of the control information, and the second format of the bit that is arranged only in the mobile station apparatus specific search area. If quantity G is the same, in a region where the mobile station apparatus specific search space and the common search space may overlap, without receiving process in the second format, it performs only reception processing of the first format.

  (H) The radio communication system of the present invention is a radio communication system having a mobile station apparatus and a base station apparatus that transmits control information to the mobile station apparatus, wherein the base station apparatus and the mobile station apparatus are The common search area is composed of predetermined control channel elements, the mobile station apparatus specific search area having the same number of control channel elements constituting the PDCCH candidate as the common search area, and the control channel elements used for the common search area A mobile station apparatus specific search region that is configured from the excluded control channel elements and has a different number of control channel elements that configure PDCCH candidates from the common search region is configured from all control channel elements.

  (I) The base station apparatus of the present invention is a base station apparatus that transmits control information to a mobile station apparatus, and is an information bit in a first format that includes information indicating a component carrier that is a format of the control information. If the number is a predetermined number of bits, at least one bit is inserted into the first format to determine a first payload size, and the first format of the first payload size is transmitted to the mobile station apparatus.

  (J) Moreover, the base station apparatus of the present invention is a base station apparatus that transmits control information to a mobile station apparatus, and is the format of the control information and the number of bits in a first format arranged in a common search area. When the number of bits of the second format arranged in the mobile station apparatus specific search area is the same as the format of the control information, the second format is arranged in an area where the common search area and the mobile station apparatus specific search area overlap Instead, only the first format is arranged and the first format is transmitted.

  (K) In addition, the base station apparatus of the present invention is a base station apparatus that transmits control information to the mobile station apparatus, and is configured to configure a common search region from predetermined control channel elements and configure PDCCH candidates. A mobile station apparatus specific search area having the same number of channel elements as the common search area is configured from control channel elements excluding control channel elements used in the common search area, and the number of control channel elements constituting the PDCCH candidate is the common search. A mobile station apparatus specific search area different from the area is configured from all control channel elements.

  (L) Moreover, the mobile station apparatus of the present invention is a mobile station apparatus that receives control information transmitted from a base station apparatus, and is a first format including information indicating a component carrier that is a format of the control information. When the number of information bits is a predetermined number of bits, the first payload size is determined by inserting at least one bit into the first format, and the first format is assumed to be the first payload size. Receive format.

  (M) The mobile station apparatus of the present invention is a mobile station apparatus that receives control information transmitted from a base station apparatus, and is a format of the control information that is in a first format arranged in a common search area. If the number of bits is the same as the format of the control information and the number of bits in the second format arranged only in the mobile station apparatus specific search area is the same, the second area is the second in the area where the common search area and the mobile station apparatus specific search area overlap. Only the first format reception process is performed without the format reception process.

  (N) Further, the mobile station apparatus of the present invention is a mobile station apparatus that receives control information transmitted from a base station apparatus, wherein a common search area is configured from predetermined control channel elements, and PDCCH candidates are The number of control channel elements constituting the mobile station apparatus specific search area having the same number of control channel elements as the common search area is composed of control channel elements excluding the control channel elements used in the common search area, and constituting the PDCCH candidate The mobile station apparatus specific search area is different from the common search area, and is composed of all control channel elements.

  (O) Moreover, the radio communication method of the present invention is a radio communication method used for a base station apparatus that transmits control information to a mobile station apparatus, and includes information indicating a component carrier that is a format of the control information. Means for determining a first payload size by inserting at least one bit into the first format when the number of information bits in the first format is a predetermined number of bits, and moving the first format of the first payload size Means for transmitting to the station apparatus;

  (P) A radio communication method according to the present invention is a radio communication method used for a base station apparatus that transmits control information to a mobile station apparatus, and is a format of the control information that is arranged in a common search area. If the number of bits in one format is the same as the format of the control information and the number of bits in the second format arranged in the mobile station apparatus specific search area is the same, the common search area and the mobile station apparatus specific search area overlap , Means for arranging only the first format without arranging the second format, and means for transmitting the first format.

  (Q) Further, the radio communication method of the present invention is a radio communication method used for a base station apparatus that transmits control information to a mobile station apparatus, and means for configuring a common search area from predetermined control channel elements. , Means for configuring a mobile station apparatus specific search area having the same number of control channel elements constituting the PDCCH candidate as the common search area from control channel elements excluding the control channel elements used for the common search area, and configuring the PDCCH candidate A mobile station apparatus specific search area having a different number of control channel elements from the common search area is configured from all control channel elements.

  (R) The radio communication method of the present invention is a radio communication method used for a mobile station apparatus that receives control information transmitted from a base station apparatus, and is a format of the control information and information indicating a component carrier Means for determining a first payload size by inserting at least one bit into the first format, wherein the first format is the first payload size. And means for receiving the first format.

  (S) The radio communication method of the present invention is a radio communication method used for a mobile station apparatus that receives control information transmitted from a base station apparatus, and is in the format of the control information and arranged in a common search area. If the number of bits in the first format and the number of bits in the second format arranged in the mobile station device specific search region are the same as the format of the control information, the common search region and the mobile station device specific search region overlap. In the area, the second format receiving process is not performed, and only the first format receiving process is performed.

  (T) A radio communication method of the present invention is a radio communication method used for a mobile station apparatus that receives control information transmitted from a base station apparatus, and a common search area is determined from a predetermined control channel element. Means for configuring, means for configuring a mobile station apparatus specific search area having the same number of control channel elements constituting a PDCCH candidate as a common search area from control channel elements excluding control channel elements used for the common search area, PDCCH candidates The mobile station apparatus specific search area in which the number of control channel elements constituting the mobile station apparatus is different from the common search area is configured from all control channel elements.

  (U) An integrated circuit according to the present invention is an integrated circuit used in a base station apparatus that transmits control information to a mobile station apparatus, and is a first format that includes information indicating a component carrier that is a format of the control information. Means for determining a first payload size by inserting at least one bit into the first format when the number of information bits of the format is a predetermined number of bits, and the mobile station apparatus assigning the first format of the first payload size Means for transmitting to.

  (V) An integrated circuit according to the present invention is an integrated circuit used in a base station apparatus that transmits control information to a mobile station apparatus, and is a first format that is a format of the control information and is arranged in a common search area. If the bit number of the second search format is the same as the format of the control information and the second format arranged in the mobile station apparatus specific search area, the common search area and the mobile station apparatus specific search area overlap with each other. Means for arranging only the first format without arranging two formats, and means for transmitting the first format.

  (W) An integrated circuit according to the present invention is an integrated circuit used in a base station apparatus that transmits control information to a mobile station apparatus, and comprises means for configuring a common search area from predetermined control channel elements, PDCCH Means for configuring a mobile station apparatus specific search area having the same number of control channel elements constituting a candidate as the common search area from control channel elements excluding the control channel elements used in the common search area; control channel constituting a PDCCH candidate A mobile station apparatus specific search area having a different number of elements from the common search area is configured from all control channel elements.

  (X) An integrated circuit of the present invention is an integrated circuit used in a mobile station apparatus that receives control information transmitted from a base station apparatus, and includes information indicating a component carrier that is a format of the control information. When the number of information bits of the first format is a predetermined number of bits, means for determining a first payload size by inserting at least one bit into the first format, and the first format is the first payload size And means for receiving the first format.

  (Y) The integrated circuit of the present invention is an integrated circuit used in a mobile station apparatus that receives control information transmitted from a base station apparatus, and is in the format of the control information and is arranged in a common search area. An area in which the common search area and the mobile station apparatus specific search area overlap when the number of bits in the first format is the same as the format of the control information and the number of bits in the second format arranged only in the mobile station apparatus specific search area Then, there is means for performing only the reception process of the first format without performing the reception process of the second format.

  (Z) An integrated circuit according to the present invention is an integrated circuit used in a mobile station apparatus that receives control information transmitted from a base station apparatus, and a common search area is configured from predetermined control channel elements. Means for configuring a mobile station apparatus specific search area having the same number of control channel elements constituting a PDCCH candidate as a common search area from control channel elements excluding control channel elements used in the common search area, and constituting a PDCCH candidate The mobile station apparatus specific search area having a different number of control channel elements from the common search area is configured by all control channel elements.

  As described above, the embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to the above, and various design changes and the like can be made without departing from the scope of the present invention. It is possible to

1 (1A, 1B, 1C) Mobile station apparatus 3 Base station apparatus 101 Upper layer processing section 103 Control section 105 Reception section 107 Transmission section 109 Channel measurement section 201 Upper layer processing section 203 Control section 205 Reception section 207 Transmission section 209 Channel measurement Unit 1013 scheduling unit 1015 downlink control information generation unit 2013 scheduling unit 2015 blind decoding control unit

Claims (7)

In a radio communication system having a mobile station apparatus and a base station apparatus that transmits control information to the mobile station apparatus,
The base station device
The payload sizes of the control information of the physical downlink control channel candidate in the common search area and the physical downlink control channel candidate in the mobile station apparatus specific search area, which are candidates for arranging the control information, are the same. The control information includes different information, and the physical downlink control channel candidate in the common search area and the physical downlink control channel candidate in the mobile station apparatus specific search area are configured by control channel elements having the same number , Arranging and transmitting the control information only to physical downlink control channel candidates in the common search region,
The mobile station device
A wireless communication system, wherein the control information is received by assuming that the control information is transmitted using a physical downlink control channel only in the common search region. In the base station device that transmits control information to the mobile station device,
The payload sizes of the control information of the physical downlink control channel candidate in the common search area and the physical downlink control channel candidate in the mobile station apparatus specific search area, which are candidates for arranging the control information, are the same. The control information includes different control information, and the physical downlink control channel candidate in the common search area and the physical downlink control channel candidate in the mobile station apparatus specific search area are configured by control channel elements having the same number. The base station apparatus, wherein the control information is arranged and transmitted only to physical downlink control channel candidates in the common search region. In a mobile station apparatus that receives control information transmitted from a base station apparatus,
In the base station apparatus, the payload sizes of the control information of the physical downlink control channel candidate in the common search area and the physical downlink control channel candidate in the mobile station apparatus specific search area, which are candidates for the control information being arranged, Control channel elements that are the same, each of the control information includes different control information, and the physical downlink control channel candidate in the common search area and the physical downlink control channel candidate in the mobile station apparatus specific search area have the same number If it consists of
A mobile station apparatus, wherein the control information is received on the assumption that the control information is transmitted using a physical downlink control channel only in the common search region. In a wireless communication method used for a base station device that transmits control information to a mobile station device,
The payload sizes of the control information of the physical downlink control channel candidate in the common search area and the physical downlink control channel candidate in the mobile station apparatus specific search area, which are candidates for arranging the control information, are the same. The control information includes different control information, and the physical downlink control channel candidate in the common search area and the physical downlink control channel candidate in the mobile station apparatus specific search area are configured by control channel elements having the same number. Is a radio communication method used for a base station apparatus, wherein the control information is arranged and transmitted only to physical downlink control channel candidates in the common search region. In a radio communication method used for a mobile station apparatus that receives control information transmitted from a base station apparatus,
In the base station apparatus, the payload sizes of the control information of the physical downlink control channel candidate in the common search area and the physical downlink control channel candidate in the mobile station apparatus specific search area, which are candidates for the control information being arranged, Control channel elements that are the same, each of the control information includes different control information, and the physical downlink control channel candidate in the common search area and the physical downlink control channel candidate in the mobile station apparatus specific search area have the same number Is used in a mobile station apparatus that performs the reception process of the control information on the assumption that the control information is transmitted using a physical downlink control channel only in the common search region. Wireless communication method. In an integrated circuit used in a base station device that transmits control information to a mobile station device,
The payload sizes of the control information of the physical downlink control channel candidate in the common search area and the physical downlink control channel candidate in the mobile station apparatus specific search area, which are candidates for arranging the control information, are the same. The control information includes different control information, and the physical downlink control channel candidate in the common search area and the physical downlink control channel candidate in the mobile station apparatus specific search area are configured by control channel elements having the same number. An integrated circuit used in a base station apparatus, wherein the control information is arranged and transmitted only to physical downlink control channel candidates in the common search area. In an integrated circuit used in a mobile station apparatus that receives control information transmitted from a base station apparatus,
In the base station apparatus, the payload sizes of the control information of the physical downlink control channel candidate in the common search area and the physical downlink control channel candidate in the mobile station apparatus specific search area, which are candidates for the control information being arranged, Control channel elements that are the same, each of the control information includes different control information, and the physical downlink control channel candidate in the common search area and the physical downlink control channel candidate in the mobile station apparatus specific search area have the same number Is used in a mobile station apparatus that performs the reception process of the control information on the assumption that the control information is transmitted using a physical downlink control channel only in the common search region. Integrated circuit.

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