JP5297298B2 - Control channel assignment apparatus, control channel assignment method, and computer program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To effectively utilize radio resources for a physical downlink layer control channel (PDCCH). <P>SOLUTION: A control channel allocation method includes: a step (S2) for PDCCH allocation ranking for a radio terminal scheduled to allocate a physical uplink data channel (PUSCH) thereto and a radio terminal scheduled to allocate a physical downlink data channel (PDSCH); and a step (S11) for determining whether or not radio resources (CCE) for PDCCH can be allocated to the radio terminals one by one in accordance with the allocation ranking. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a control channel assignment apparatus, a control channel assignment method, and a computer program.

  In recent years, standards for new wireless communication systems have been studied by various standardization organizations (for example, 3GPP (3rd Generation Partnership Project), 3GPP2 (3rd Generation Partnership Project 2), IEEE 802.16 standardization organizations, etc.). For example, as a successor system of the third generation (3G) cellular system, LTE (Long Term Evolution: official name is “Evolved Universal Terrestrial Radio Access (E-UTRA)”. See Non-Patent Documents 1 and 2) and UMB ( Next generation cellular systems (also called 3.9G cellular systems) such as Ultra Mobile Broadband are being considered. Furthermore, an IMT-Advanced system (also referred to as a 4G cellular system), which is an evolution system of the 3.9G cellular system, is being studied.

  Some wireless communication systems under consideration adopt an Orthogonal Frequency Division Multiple Access (OFDMA) scheme. For example, LTE, UMB, WiMAX, and LTE-Advanced and IEEE 802.16m currently being studied for 4G cellular systems.

  In a wireless communication system using the OFDMA scheme (hereinafter referred to as an OFDMA system), a plurality of subcarriers within an available frequency band (hereinafter referred to as a system band) can be allocated to a mobile terminal. Moreover, the allocation content can be changed with time. Therefore, in general, in an OFDMA system, radio resources can be allocated flexibly using a two-dimensional radio resource composed of a frequency component and a time component.

  In an OFDMA system compliant with LTE (hereinafter referred to as LTE system), a physical channel control channel (hereinafter referred to as downlink physical layer) called downlink (link in the direction from the base station to the terminal) called PDCCH (Physical Downlink Control Channel). (Referred to as control channel) is used to transmit information on the physical layer data channel from the base station to the wireless terminal. A physical layer data channel (hereinafter referred to as an uplink physical layer data channel) in the uplink (link in the direction from the terminal to the base station) is referred to as a PUSCH (Physical Uplink Shared Channel). A downlink physical layer data channel (hereinafter referred to as a downlink physical layer data channel) is referred to as a PDSCH (Physical Downlink Shared Channel).

  In the LTE system, a base station assigns PDCCH that transmits PUSCH information or PDSCH information to a radio terminal that is to be assigned PUSCH or PDSCH. In PDCCH allocation, PDCCH radio resources are allocated. FIG. 4 shows a downlink subframe configuration in the LTE system. As shown in FIG. 4, downlink subframes (hereinafter referred to as downlink subframes) are two-dimensional radio resources in the time direction and the frequency direction (14 OFDM symbols in the time direction and system bandwidth in the frequency direction). Width). The downlink subframe is divided into a PDCCH region and a PDSCH region in the time direction. As the PDCCH area, one, two, or three OFDM symbols are secured from the beginning in the time direction. Note that the PDCCH region is also used for downlink control channels (PCFICH and PHICH) other than PDCCH.

  FIG. 5 is a conceptual diagram for explaining a method for assigning PDCCH radio resources. The PDCCH radio resources are allocated in units of radio resources called CCE (Control Channel Element). One CCE is composed of nine REGs (Resource Element Groups). And as shown in FIG. 5, the order which assigns a REG number is a time direction ahead of a frequency direction. One, two, four, or eight CCEs are assigned to the PDCCH of one radio terminal. This number of CCEs corresponds to an aggregation level. For example, when the aggregation level is 8, the number of CCEs assigned to the wireless terminal is 8. In the LTE system, a set of CCE numbers that can be used in a certain subframe of a certain wireless terminal is uniquely determined by the number of the subframe and the number of the wireless terminal. For example, for a certain subframe number and a certain wireless terminal number, a set of CCE numbers when the aggregation level is 4 (the number of CCEs is 4) is “12, 13, 14, 15” and “16, 17, 18, There are two combinations of “19”.

  The PDCCH signal is encoded with an error correction code, and the coding rate is determined so as to decrease as the number of CCEs allocated to the PDCCH increases. The coding rate varies depending on the payload length of the PDCCH. For example, when the payload length of the PDCCH is 48, the coding rate when the number of CCEs is 1 is 2/3 and the coding rate when the number of CCEs is 2. Is 1/3, the coding rate is 1/6 when the number of CCEs is 4, and the coding rate is 1/12 when the number of CCEs is 8.

  In the PDCCH region, the width in the frequency direction is fixed by the system bandwidth, but the time direction is variable between one and three OFDM symbols. However, since the time direction is ahead of the frequency direction in the order of assigning REG numbers constituting the CCE in the PDCCH region, it is necessary to determine the number of OFDM symbols for PDCCH in advance. In the example of FIG. 5, the number of OFDM symbols for PDCCH is 3, and three OFDM symbols are secured as the PDCCH region.

  The wireless terminal performs blind decoding on the PDCCH OFDM symbol. This is because the CCE number to be decoded is not notified to the wireless terminal. The range (set of CCE numbers) in which the wireless terminal performs blind decoding is called a search space. The formula for calculating the search space is specified.

  In the LTE system, PUSCH information or PDSCH information cannot be transmitted to a wireless terminal unless a PDCCH is assigned to a wireless terminal to which PUSCH or PDSCH is to be assigned. For this reason, for example, in the conventional technique of Non-Patent Document 3, when PDCCH cannot be allocated in a certain downlink subframe, PDCCH allocation is attempted in the next downlink subframe. In the prior art of Non-Patent Document 4, when sufficient PDCCH radio resources to be allocated to a radio terminal are not secured in a certain downlink subframe, the PDCCH is not allocated to the radio terminal.

3GPP TS 36.211, “Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation (Release 8)” 3GPP TS 36.213, “Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures (Release 8)” Yoshinori Tanaka, Yoshihiro Kawasaki, “Evolved UTRA downlink control information multiplexing method and its features”, 2008 IEICE Society Conference, BS-4-3, September 2008 Akihiko Nishio, Takahisa Aoyama, Christain Wengerter, Daichi Imamura, Hidetoshi Suzuki, “Adaptive Transmission Technology of Control Information in 3G-LTE”, Panasonic Technical Journal, Vol.55, No.1, April, 2009

  As described above, if the PDCCH is not assigned, the physical layer data channel (PUSCH, PDSCH) to be assigned to the wireless terminal cannot be used, so it is important how to use finite PDCCH radio resources. Become.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a control channel allocating device, a control channel allocating method, and a control channel allocating device capable of effectively using downlink physical layer control channel (PDCCH) radio resources. To provide a computer program.

  In order to solve the above problems, a control channel allocation apparatus according to the present invention provides a downlink for transmitting physical layer data channel information to a radio terminal to which an uplink physical layer data channel or a downlink physical layer data channel is to be allocated. In a control channel assignment apparatus that assigns a physical layer control channel, downlink physical layer control for a wireless terminal to which an uplink physical layer data channel is to be assigned and a wireless terminal to which a downlink physical layer data channel is to be assigned An allocation order assigning unit for assigning channel allocation order, and a radio resource allocation determination unit for determining whether or not radio resources for downlink physical layer control channels can be allocated to the radio terminal one by one according to the allocation order. It is characterized by.

  In the control channel allocation apparatus according to the present invention, the radio terminal is provided with radio resource amount determination means for determining a radio resource amount for a downlink physical layer control channel required for the radio terminal based on the reception quality estimation value of the radio terminal. It is characterized by.

  The control channel allocation method according to the present invention performs control for allocating a downlink physical layer control channel for transmitting physical layer data channel information to a wireless terminal to which an uplink physical layer data channel or a downlink physical layer data channel is to be allocated. A method for assigning a downlink physical layer control channel to a wireless terminal to which an uplink physical layer data channel is to be assigned and a wireless terminal to which a downlink physical layer data channel is to be assigned, as a channel assignment method And determining whether or not radio resources for downlink physical layer control channels can be allocated to the radio terminals one by one in accordance with the allocation order.

The computer program according to the present invention allocates a downlink physical layer control channel for transmitting physical layer data channel information to a radio terminal to which an uplink physical layer data channel or a downlink physical layer data channel is to be allocated. A computer program for performing processing, and assigning a downlink physical layer control channel to a wireless terminal to which an uplink physical layer data channel is to be assigned and a wireless terminal to which a downlink physical layer data channel is to be assigned A computer program for causing a computer to execute a ranking step and a step of determining whether or not radio resources for downlink physical layer control channels can be allocated to the radio terminals one by one according to the allocation ranking. And
As a result, the control channel allocation device described above can be realized using a computer.

  According to the present invention, it is possible to effectively use the downlink physical layer control channel (PDCCH) radio resource.

It is a block diagram which shows the physical layer channel allocation structure in the base station 1 of the LTE system which concerns on one Embodiment of this invention. It is a block diagram which shows the structure of the PDCCH allocation part 10 shown in FIG. It is a flowchart which shows the procedure of the control channel allocation method which concerns on one Embodiment of this invention. It is a figure which shows the sub-frame structure of the downlink in a LTE system. It is a conceptual diagram for demonstrating the allocation method of the radio | wireless resource for PDCCH.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing a physical layer channel assignment configuration in a base station 1 of an LTE system according to an embodiment of the present invention. In FIG. 1, the base station 1 includes a PDCCH (downlink physical layer control channel) allocation unit 10, a PDSCH (downlink physical layer data channel) allocation unit 11, and a PUSCH (uplink physical layer data channel) allocation unit 12.

  The PDCCH allocation unit 10 allocates PDCCH that transmits PUSCH information or PDSCH information to a radio terminal to which PUSCH or PDSCH is to be allocated. The PDSCH allocation unit 11 allocates PDSCH to wireless terminals. The PUSCH allocation unit 12 allocates PUSCH to wireless terminals.

  Information on all wireless terminals to which the PDSCH is to be allocated is sent from the PDSCH allocation unit 11 to the PDCCH allocation unit 10 as CCE allocation determination information. The PDCCH allocation unit 10 returns information on the success / failure of PDCCH allocation to all wireless terminals to which the PDSCH is allocated to the PDSCH allocation unit 11 as CCE allocation success / failure information.

  Information on all wireless terminals to which a PUSCH is to be allocated is sent from the PUSCH allocation unit 12 to the PDCCH allocation unit 10 as CCE allocation determination information. The PDCCH allocation unit 10 returns information on the success or failure of PDCCH allocation to all wireless terminals to which PUSCH is allocated to the PUSCH allocation unit 12 as CCE allocation success / failure information.

  FIG. 2 is a block diagram showing a configuration of PDCCH allocation section 10 shown in FIG. In FIG. 2, the PDCCH allocation unit 10 includes an input information acquisition unit 21, an aggregation level determination unit 22, a CCE allocation unit 23, a search space management unit 24, and an output information creation unit 25.

  The input information acquisition unit 21 acquires input information used by the PDCCH allocation unit 10. The aggregation level determination unit 22 determines the aggregation level. The aggregation level includes the number of CCEs (1, 2, 4, or 8) allocated to the PDCCH of one wireless terminal and the coding rate (in this embodiment, the PDCCH payload length is 48, 2/3, 1 / 3, 1/6 or 1/12). The aggregation level (z = 1) corresponds to “CCE number = 1, coding rate = 2/3”, and the aggregation level (z = 2) corresponds to “CCE number = 2, coding rate = 1/3”. The aggregation level (z = 4) corresponds to “CCE number = 4, coding rate = 1/6”, and the aggregation level (z = 8) corresponds to “CCE number = 8, coding rate = 1/12”. Corresponding to Therefore, the number of CCEs assigned to the PDCCH of a certain wireless terminal and the coding rate for the PDCCH are determined by the aggregation level.

  The CCE assigning unit 23 assigns a CCE to a wireless terminal to which a PUSCH or PDSCH is to be assigned. A PDCCH is reserved for a radio terminal that has been successfully assigned a CCE. The search space management unit 24 searches for a search space. The output information creation unit 25 creates CCE allocation success / failure information. The CCE allocation success / failure information returned to the PDSCH allocation unit 11 includes information on the success / failure of CCE allocation for all wireless terminals to which the PDSCH is to be allocated. The CCE allocation success / failure information returned to the PUSCH allocation unit 12 includes information on the success / failure of CCE allocation for all wireless terminals to which the PUSCH is to be allocated.

  Next, the operation of the PDCCH allocation unit 10 shown in FIG. 2 will be described with reference to FIG. FIG. 3 is a flowchart showing the procedure of the control channel allocation method according to this embodiment.

  The PDCCH allocating unit 10 performs the PDCCH allocation process in the downlink subframe at the time when the CCE allocation determination information is received from both the PDSCH allocating unit 11 and the PUSCH allocating unit 12 at the PDCCH allocation timing of a certain downlink subframe. 3 processing is started.

  In FIG. 3, in step S1, the input information acquisition unit 21 acquires the number of OFDM symbols for PDCCH, and the CCE allocation unit 23 sets the CCE upper limit amount using the number of OFDM symbols for PDCCH. The number of OFDM symbols for PDCCH is specified by an operator, for example. The CCE upper limit amount is the number of CCEs corresponding to the total radio resource amount (radio resource amount determined by the number of OFDM symbols for PDCCH and the system bandwidth) that can be used for PDCCH in the downlink subframe to which PDCCH is allocated (ie, as shown in FIG. 4). This is the number obtained by subtracting the number of CCEs used in other downlink control channels (PCFICH and PHICH) from the total number of CCEs included in the PDCCH region.

  Next, in step S2, the CCE assigning unit 23 assigns an assignment order to all of the PDCCH assignment target wireless terminals (hereinafter referred to as assignment target terminals). Here, the set of all allocation target terminals to which allocation order is to be assigned includes all of the allocation target terminals indicated by the CCE allocation determination information received from the PDSCH allocation unit 11 and the CCE allocation determination received from the PUSCH allocation unit 12. It consists of all of the allocation target terminals indicated by the information. The CCE allocation unit 23 determines the allocation order of each allocation target terminal based on the CCE allocation priority for each allocation target terminal. For allocation target terminals having the same CCE allocation priority, the allocation order of each allocation target terminal is further determined based on the terminal priority for each allocation target terminal. The CCE allocation priority and the terminal priority are included in the CCE allocation determination information.

  The CCE allocation priority includes a channel type and a packet type. The CCE allocation priority related to the channel type is the type (for example, control channel and data) of the higher layer (for example, RRC layer) scheduled to be transmitted on the physical layer data channel (PUSCH or PDSCH) to be allocated to the allocation target terminal. This is the priority for each channel. The CCE allocation priority related to the packet type is a priority for each type (for example, initial transmission packet and retransmission packet) of a packet scheduled to be transmitted on the physical layer data channel (PUSCH or PDSCH) to be allocated to the allocation target terminal. . The terminal priority may be based on a proportional fairness evaluation function value or based on communication quality such as communication delay.

  Next, in step S3, the CCE allocating unit 23 checks whether there are any allocation target terminals that have not yet been selected as processing targets. As a result, when there remains an unselected allocation target terminal, the process proceeds to step S4, and when there is no unselected allocation target terminal, the process proceeds to step S5.

  In step S4, the CCE allocating unit 23 checks whether there are any remaining CCEs that can be allocated. As a result, if an allocatable CCE still remains, the process proceeds to step S6, and if there is no allocatable CCE, the process proceeds to step S5.

  In step S5, the output information creation unit 25 creates CCE allocation success / failure information. The CCE allocation success / failure information returned to the PDSCH allocation unit 11 includes information on the success / failure of CCE allocation for all wireless terminals to which the PDSCH is to be allocated. The CCE allocation success / failure information returned to the PUSCH allocation unit 12 includes information on the success or failure of CCE allocation for all wireless terminals to which the PUSCH is to be allocated.

  In step S6, the CCE allocation unit 23 selects one allocation target terminal according to the allocation order. The allocation target terminal of the selection result is hereinafter referred to as a selection terminal. In step S7, the input information acquisition unit 21 acquires an SINR (Signal to Interference and Noise power Ratio) estimation value of the selected terminal. SINR represents the reception quality of the wireless terminal.

  Next, in step S8, the aggregation level determination unit 22 compares the SINR estimated value of the selected terminal with the SINR reference value. The SINR reference value is provided for each aggregation level. The SINR reference value corresponding to a certain aggregation level is a SINR threshold value that can achieve a certain error rate depending on the coding rate determined by the aggregation level.

The SINR reference value (z ′) corresponding to the parameter (z ′) indicating the aggregation level (z) has the following relationship.
SINR reference value (z ′) <SINR reference value (z′−1)
However, z ′ is any one of 1, 2, 3, and 4. “Z ′ = 1” indicates an aggregation level (1) of “CCE number = 1”, “z ′ = 2” indicates an aggregation level (2) of “CCE number = 2”, and “z ′ = 3”. Indicates an aggregation level (4) of “CCE number = 4”, and “z ′ = 4” indicates an aggregation level (8) of “CCE number = 8”. Therefore, the SINR reference value of the aggregation level with a large number of CCEs and a low coding rate is a smaller value.

  The aggregation level determination unit 22 sequentially compares the SINR estimated value of the selected terminal with the SINR reference value of each aggregation level.

  Subsequently, in step S9, the aggregation level determination part 22 determines the aggregation level of a selection terminal based on the comparison result of step S8. This determination of the aggregation level is performed by determining which SINR estimated value is between the SINR reference value of which aggregation level and the SINR reference value of which aggregation level. Specifically, when “SINR reference value (z ′) ≦ SINR estimated value <SINR reference value (z′−1)” is satisfied, the aggregation level (z) of the SINR reference value (z ′) is selected. (However, there is no SINR reference value (0)).

  Next, in step S10, the search space management unit 24 searches the search space corresponding to the selected terminal whether there are free CCEs corresponding to the number of CCEs of the aggregation level (z) of the selected terminal. As a result of this search, if there are empty CCEs corresponding to the number of CCEs (step S11, YES), the process proceeds to step S12.

  In step S12, the CCE allocating unit 23 allocates, to the selected terminal, free CCEs that are found in step S10 and corresponding to the number of CCEs at the aggregation level (z) of the selected terminal. At this time, if there are more CCEs than the number of CCEs at the aggregation level (z) of the selected terminal, the number of CCEs corresponding to the aggregation level (z) is selected at random from the first CCE number of the search space. To do. Thereafter, the selected terminal is excluded from the allocation target terminals in step S13, and the process returns to step S3. In this case, the CCE allocation to the selected terminal is successful and the PDCCH allocation is possible.

  On the other hand, as a result of the search of the search space in step S10, if there are no free CCEs corresponding to the number of CCEs at the aggregation level (z) of the selected terminal (step S11, NO), the CCE allocating unit 23 assigns the CCE to the selected terminal. In step S13, the selected terminal is excluded from the allocation target terminals, and the process returns to step S3. In this case, CCE allocation to the selected terminal is unsuccessful, and PDCCH allocation is impossible.

  As described above, according to the present embodiment, PDCCH allocation ranks are assigned to radio terminals to which PUSCHs are to be allocated and radio terminals to which PDSCHs are to be allocated. It is determined whether or not CCE allocation is possible for the wireless terminal. As a result, whether or not CCE allocation is possible is determined based on the combined priority of the PUSCH allocation candidate terminal and the PDSCH allocation candidate terminal, which can contribute to effective use of limited PDCCH radio resources.

  Further, according to the present embodiment, the aggregation level (that is, the required number of CCEs) is determined based on the SINR estimation value of the PDCCH allocation target terminal. As a result, the required number of CCEs can be appropriately determined for the PDCCH allocation target terminal, and effective use of the limited PDCCH radio resources can be further promoted.

Note that a program for realizing each step shown in FIG. 3 is recorded on a computer-readable recording medium, and the program recorded on the recording medium is read into a computer system and executed, thereby executing control channel allocation processing. May be performed. Here, the “computer system” may include an OS and hardware such as peripheral devices.
“Computer-readable recording medium” refers to a flexible disk, a magneto-optical disk, a ROM, a writable nonvolatile memory such as a flash memory, a portable medium such as a DVD (Digital Versatile Disk), and a built-in computer system. A storage device such as a hard disk.

Further, the “computer-readable recording medium” means a volatile memory (for example, DRAM (Dynamic DRAM) in a computer system that becomes a server or a client when a program is transmitted through a network such as the Internet or a communication line such as a telephone line. Random Access Memory)), etc., which hold programs for a certain period of time.
The program may be transmitted from a computer system storing the program in a storage device or the like to another computer system via a transmission medium or by a transmission wave in the transmission medium. Here, the “transmission medium” for transmitting the program refers to a medium having a function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line.
The program may be for realizing a part of the functions described above. Furthermore, what can implement | achieve the function mentioned above in combination with the program already recorded on the computer system, and what is called a difference file (difference program) may be sufficient.

As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, the specific structure is not restricted to this embodiment, The design change etc. of the range which does not deviate from the summary of this invention are included.
For example, in the control channel allocation method shown in FIG. 3, the SINR reference value may be provided for each “PDCCH DCI format”. “PDCCH DCI format” is a format number indicating the type of packet to be transmitted to the wireless terminal.

  Note that, as the information indicating the reception quality of the wireless terminal, SINR is used in the above-described embodiment, but information other than SINR may be used.

DESCRIPTION OF SYMBOLS 10 ... PDCCH allocation part, 21 ... Input information acquisition part, 22 ... Aggregation level determination part, 23 ... CCE allocation part, 24 ... Search space management part, 25 ... Output information creation part

Claims (4)

In a control channel allocation apparatus that allocates a downlink physical layer control channel that transmits physical layer data channel information to a radio terminal to which an uplink physical layer data channel or a downlink physical layer data channel is to be allocated,
Allocation order assigning means for assigning a downlink physical layer control channel allocation order for wireless terminals to which an uplink physical layer data channel is scheduled and wireless terminals to be allocated a downlink physical layer data channel;
Radio resource allocation determination means for determining whether or not radio resources for downlink physical layer control channels can be allocated to the radio terminals one by one according to the allocation order ,
The allocation order assigning means is a priority for each type of higher layer channel scheduled to be transmitted on the physical layer data channel scheduled to be allocated to the wireless terminal, or transmitted on the physical layer data channel scheduled to be allocated to the wireless terminal. Assigning the priority order of the downlink physical layer control channel based on the priority for each type of packet that is scheduled,
A control channel allocating device. In a control channel allocation apparatus that allocates a downlink physical layer control channel that transmits physical layer data channel information to a radio terminal to which an uplink physical layer data channel or a downlink physical layer data channel is to be allocated,
Allocation order assigning means for assigning a downlink physical layer control channel allocation order for wireless terminals to which an uplink physical layer data channel is scheduled and wireless terminals to be allocated a downlink physical layer data channel;
Radio resource allocation determination means for determining whether or not radio resources for downlink physical layer control channels can be allocated to the radio terminals one by one according to the allocation order;
On the basis of the reception quality estimate of the wireless terminal, and a radio resource amount determining means for determining the radio resource amount for the required downstream physical layer control channel to the wireless terminal,
A predetermined reception quality reference value corresponding to the radio resource amount for each downlink physical layer control channel is provided,
The radio resource amount determination means determines a radio resource amount for a downlink physical layer control channel required for the radio terminal by comparing the reception quality estimation value of the radio terminal with the reception quality reference value.
A control channel allocating device. A control channel assignment method for assigning a downlink physical layer control channel for transmitting physical layer data channel information to a wireless terminal to which an uplink physical layer data channel or a downlink physical layer data channel is to be assigned,
An assignment ordering step for assigning an order of assignment of the downlink physical layer control channel to a wireless terminal to which an uplink physical layer data channel is to be assigned and a wireless terminal to which a downlink physical layer data channel is to be assigned;
According to the assignment order, and determining the allocation availability of each one the radio resource for the downlink physical layer control channel for the wireless terminal, only including,
The allocation order assigning step includes a priority for each type of higher layer channel scheduled to be transmitted on the physical layer data channel scheduled to be allocated to the wireless terminal, or transmission on the physical layer data channel scheduled to be allocated to the wireless terminal. Assigning the priority order of the downlink physical layer control channel based on the priority for each type of packet that is scheduled,
And a control channel assignment method. A computer program for performing control channel assignment processing for assigning a downlink physical layer control channel for transmitting physical layer data channel information to a wireless terminal to which an uplink physical layer data channel or a downlink physical layer data channel is to be assigned There,
An assignment ordering step for assigning an order of assignment of the downlink physical layer control channel to a wireless terminal to which an uplink physical layer data channel is to be assigned and a wireless terminal to which a downlink physical layer data channel is to be assigned;
Determining whether or not radio resources for downlink physical layer control channels can be allocated to the radio terminals one by one in accordance with the allocation order , and a computer program for causing a computer to execute ,
The allocation order assigning step includes a priority for each type of higher layer channel scheduled to be transmitted on the physical layer data channel scheduled to be allocated to the wireless terminal, or transmission on the physical layer data channel scheduled to be allocated to the wireless terminal. Assigning the priority order of the downlink physical layer control channel based on the priority for each type of packet that is scheduled,
A computer program characterized by the above .

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