JP5062256B2 - Control information transmission and reception method in radio communication system, and radio base station and radio terminal using the same - Google Patents

Description

  The present invention relates to a method for transmitting and receiving control information in a radio communication system, and a radio base station and radio terminal using the same.

IEEE (Institute of
Electrical and Electronics Engineers (P-MP): Point-to-Multipoint (P-MP) that allows multiple terminals to connect to a wireless base station in a wireless communication system by the 802.16 Working Group (hereinafter simply referred to as 802.16 WG) Type communication system is defined.

The 802.16 WG mainly uses the 802.16d specification for fixed communication applications (802.16-2004).
(Non-Patent Document 1) and the 802.16e specification (802.16e-2005) (Non-Patent Document 2) for mobile communication applications are defined.

The 802.16 WG defines multiple physical layers, but orthogonal frequency division multiple (OFDM)
Frequency Division Multiplexing (OFDM) and Orthogonal Frequency (OFDMA)
Technology such as Division Multiplexing access) is mainly used.

  FIG. 1 shows a service image of an 802.16d / e wireless communication system. As shown in the figure, one wireless base station (BS) 1 (hereinafter simply referred to as a wireless base station BS) is connected to a plurality of wireless terminals (MS) 2-1, 2-2, 2-3 ( Hereinafter, unless otherwise specified, it is simply referred to as a wireless terminal MS).

In 802.16d / e, a radio base station BS uses radio resources (OFDM symbols: Symbol, subchannel: Subchannel) allocation information in radio frames, and information including the modulation scheme and coding scheme to be used and the combination of the rates. Burst profile (Burst
Profile) is notified to the subordinate radio terminal MS by broadcasting broadcast information called a DL (Downlink) -MAP message. Information is sent from the radio terminal MS to the radio base station BS by an UP (Uplink) -MAP message.

  FIG. 2 shows an example of a radio frame. The radio frame includes a downlink (DL) subframe transmitted from the radio base station BS to the radio terminal MS and an uplink (UL) subframe transmitted from the radio terminal MS to the radio base station BS. The

  The figure shows a method of time-multiplexing the downlink DL and the uplink UL, but frequency multiplexing can also be used by assigning different frequency bands to the downlink DL and the uplink UL.

  As shown in FIG. 2, a fixed pattern synchronization signal called a preamble 100 is transmitted from the radio base station BS at the head of the radio frame. The radio terminal MS uses the preamble 100 to establish synchronization with the radio base station BS.

Frame control header (FCH: Frame following preamble 100)
(Control Header) 101 represents the encoding method used to transmit the subsequent DL-MAP message 102 and the size of the DL-MAP message 102, and allows the wireless terminal MS to receive the DL-MAP message 102.

The DL-MAP message 102 and the UL-MAP message 103 are respectively assigned to downlink DL radio resources (symbol: Symbol, subchannel: Subchannel, these are called burst: Burst), and burst profiles to be used (Burst
Specify Profile.

In the example shown in FIG. 2, the DL-MAP message 102 is burst # 1 (DL
Designates which radio terminal MS to use radio resource allocation from Burst # 1) to Burst # 5 (DL Burst # 5).

On the other hand, UL-MAP message 103 is burst # 1 (UL
A ranging subchannel that can be used in common by all radio terminals MS in addition to which radio terminal MS uses radio resource allocation from Burst # 1) to Burst # 5 (UL Burst # 5) (Ranging
Subchannel) 104 is designated.

  The DL-MAP message 102 designates burst allocation in the radio frame in which the DL-MAP message 102 is transmitted, whereas the UL-MAP message 103 is the next to the radio frame in which the UL-MAP message 103 is transmitted. Specifies burst allocation for UL subframes in (or later) radio frames.

  The table shown in FIG. 3 shows the fields included in the DL-MAP message 102. Various information is included in DL-MAP_IE at the bottom of the table, for example, downlink burst allocation information.

  The table shown in FIG. 4 shows an example of the burst profile DL-MAP_IE in the bottom column of FIG. In the table, a downlink interval usage code (DIUC) 200 is a code representing a modulation method and a coding method (including a coding rate) of a burst specified by the burst profile DL-MAP_IE.

Also, connection ID (CID: Connection
ID) 201 is an identifier of a connection of a packet included in a burst specified by the burst profile DL-MAP_IE, and the wireless terminal MS recognizes the connection ID 201 which is an identifier of the connection of this packet and determines a burst to be decoded. You can choose.

  Further, FIG. 5 shows a concept of designating a downlink burst by the burst profile DL-MAP_IE.

Symbol offset 202 shown in FIG. 4 and subchannel offset (Subchannel)
Offset) 203 specifies the start position of the downlink burst. Further, the size of the downlink burst is designated by the number of subchannels (Number of Subchannels) 204. FIG. 5 shows downlink burst # 2 (DL
The designation for burst # 2) is shown.

  FIG. 6 is a table showing fields included in the UL-MAP message 103. Various information is included in the burst profile UL-MAP_IE in the lowermost column in the figure, for example, burst allocation information on the uplink toward the radio base station BS.

In the table shown in Fig. 7, burst profile UL-MAP
An example of IE is shown. In the figure, Uplink Interval Usage Code (UIUC) 301 is a burst profile UL-MAP.
It is a code representing a burst modulation scheme and coding scheme (including coding rate) specified by IE.

The connection ID (CID) 300 is a burst profile UL-MAP.
This is an identifier for identifying a radio terminal MS to which a burst designated and fixed by IE is assigned.

Basic connection ID of wireless terminal MS (basic
connection ID) is used. The period (Duration) 302 represents the amount of radio resources to be allocated. Radio resource to be allocated (Subchannel: Subchannel
And the symbol (Symbol time) are relatively specified by the description order of the burst profile UL-MAP_IE in the UL-MAP message.

FIG. 8 shows an example of uplink burst allocation. As shown on the right side of the figure, slots are sequentially assigned to the time axis (in the direction of Symbol), and the uplink zone (Uplink
Slots corresponding to the number of slots (Slots) specified by the period (Duration) 302 are allocated to the uplink burst while moving to the next subchannel (Subchannel) at the break of Zone.

The next uplink burst will continue to be assigned from the next slot. Therefore, uplink burst allocation is different from downlink bursts, which are represented as squares by the number of subchannels and symbols.
It can be in the form of “chips”.

  In FIG. 8, a subchannel (Subchannel) represents a logical number before rotation. In the figure, PUSC is assumed as permutation, and one slot is illustrated as one subchannel × 3 symbols (see FIG. 8, A).

The UL-MAP determines which burst (Slot) is allocated from which burst within the Uplink Zone.
It is determined by the order of the burst profile UL-MAP-IE included in the message 103.

9 shows the uplink zone (Uplink) shown in FIG.
An example of a UL-MAP message 103 for allocating uplink bursts in (Zone) is shown.

A in the top row (UL link Zone Switch
IE) specifies the beginning symbol of the relevant uplink zone. B (UL link Zone Switch IE) at the bottom line designates the start symbol of the next uplink zone (UL Zone). This tells you the end of the previous zone.

  Further, in FIG. 9, in the area C, slots in the zone are allocated to uplink bursts by the number of slots specified in the period (Duration) in the order of listed burst profiles (Burst Profile IE). . Area D is a CDMA bandwidth request profile specified by the number of subchannels × number of slots. Refer to the corresponding UL-MAP message 103.

As described above, the radio base station BS transmits a DL-MAP message 102 including radio resource allocation information for communicating with the radio terminal MS to the radio terminal MS. At this time, the information of the MAP message is a burst profile (Burst profile) that is most resistant to path loss and noise so that all wireless terminals MS within the service area of the wireless base station BS can receive the information.
Profile).

  However, the burst profile that is most resistant to path loss and noise has poor wireless resource usage efficiency. Therefore, information on the wireless terminal MS that can communicate with a more efficient burst profile is also transmitted with an inefficient burst profile, and thus there is a problem that the usage efficiency of radio resources is poor.

  In Patent Document 1, in order to solve such a problem, information common to all wireless terminals is reliably transmitted with an inefficient burst profile. Information addressed to a wireless terminal that can communicate with a burst profile that is more efficient than a burst profile used for transmission of common information can be transmitted using the burst profile that can be received by the corresponding wireless terminal MS.

  Specifically, Patent Document 1 discloses the following technical features.

  First, the common information includes burst information (position and burst profile) in which individual information is transmitted.

  Secondly, the individual information may be a burst profile that is more robust than the burst profile used for user data communication with the wireless terminal MS.

  Third, the common information uses the most robust burst profile among burst profiles supported by the system or a burst profile sufficiently robust to communicate with the connected wireless terminal MS.

  Fourthly, the radio terminals MS are grouped according to the channel state, and common allocation information for each group can be used.

  FIG. 10 shows an example of transmission of allocation information according to Patent Document 1. In this figure, DL-MAP # 1 including common information and a burst profile according to the channel state (CINR, etc.) of the radio terminal MS are transmitted.

  At this time, in order to more reliably receive the individual information, the individual information can be transmitted using a burst profile that is more robust than the burst profile used for user data communication.

For example, DL-MAP # 2 (FIG. 10, B) transmitted with QPSK 1/2 includes QPSK.
Individual information addressed to the radio terminal MS that communicates user data with 1/2, QPSK 3/4, and 16QAM 1/2 is included. For DL-MAP # 3 (Fig. 10, C) transmitted by 16QAM 1/2, 16QAM
Individual information addressed to the radio terminal MS that communicates user data with 2/3, 16QAM 3/4, and 64QAM 1/2 is included.

Also, DL-MAP # 1 including common information includes Burst information (location and Burst from DL-MAP # 2 to DL-MAP # 4).
Profile) information is included (FIG. 10, A).
IEEE Std 802.16TM-2004 IEEE Std 802.16eTM-2005 Special Table 2007-511975

  In the wireless communication system as shown in the above-mentioned Patent Document 1, it is assumed that MAP information is received using a wireless terminal conforming to IEEE 802.16e, that is, an inefficient burst profile (QPSK 1/2). There is a problem that wireless terminals cannot coexist.

  In other words, there arises a problem that it is impossible to coexist with an 802.16m-compliant wireless terminal MS, which will be studied as the next version of 802.16e.

  Further, in the method disclosed in Patent Document 1, the burst profile for transmitting the allocation information for the radio terminal MS is determined only by the “channel state”. However, dividing the control information for each burst profile using only the channel state as a parameter is due to the generation of unused slots (Slot), header + CRC (error correction cyclic code), by sending multiple control information. Due to the overhead, the amount of radio resources actually used may increase instead.

Radio resources are used in units called slots “Slot”. For example, the slot is 4 subcarriers out of 28 subcarriers.
x Defined with 2 OFDMA symbols (Symbols), QPSK 1/2 corresponds to 24-bit information.

  Furthermore, the common information includes the position of all individual information and burst profile information, which degrades efficiency.

  That is, since it is necessary for the radio terminal MS to see all the individual information in order to confirm whether or not there is an assignment addressed to itself, the common information is used to notify the position of all the individual information and the burst profile information. There is no necessity.

  Accordingly, an object of the present invention is to provide a service by mixing a wireless terminal of a conventional standard and a wireless terminal of a new standard, and to transmit control information in a wireless system that enables further effective use of wireless resources. A receiving method, and a radio base station and a radio terminal using the same are provided.

  In order to solve the above problems, the present invention employs the following basic procedure.

  From the registration information of the wireless terminal MS (for example, registration of the existing standard 16e or the new standard 16m), it is determined whether or not individual control information can be received with a coding scheme and a modulation scheme different from the common information.

  A required radio resource amount is calculated to transmit control information.

  An encoding scheme and a modulation scheme that minimize the required radio resource amount are determined.

  Further, the individual information is included in the individual information transmitted by the encoding method and the modulation method having lower efficiency than the encoding method and the modulation method that require radio resources for transmitting the individual information.

  According to the above feature of the present invention, a service can be provided by mixing a wireless terminal of a conventional standard and a wireless terminal of a new standard, and further effective utilization of wireless resources is possible.

1 is a diagram illustrating a service image of an 802.16d / e wireless communication system. FIG. It is a figure which shows an example of a radio | wireless frame. It is a figure which shows the field contained in a DL-MAP message. . FIG. 4 is a diagram illustrating an example of a burst profile (BurstProfile) of a burst profile DL-MAP_IE in the lowermost column of FIG. 3. It is a figure which shows the concept which designates a downlink burst by burst profile DL-MAP_IE. It is a figure which shows the table which shows the field contained in a UL-MAP message. It is a figure which shows the example of the burst profile UL-MAPIE. It is a figure which shows the example of allocation of an uplink burst (Uplink Burst). It is a figure which shows the example of the UL-MAP message which performs UL burst allocation in Uplink Zone shown in FIG. It is a figure which shows the example of transmission of the allocation information by patent document 1. FIG. It is a figure which shows the production | generation / transmission flowchart of the allocation message in radio | wireless base station BS according to this invention. It is a figure which shows the example of the correspondence table of the burst profile which supports the interchannel interference noise ratio CINR which is radio channel state information. It is a figure which shows the example of an allocation message production | generation table. It is a figure which shows the example of transmission of an allocation message. It is a figure which shows the block structural example of radio base station BS which performs the process according to this invention. It is an example of a radio | wireless terminal management table. It is a figure which shows the reception process flowchart of the MAP message in the radio | wireless terminal MS of the conventional standard according to this invention, and the radio | wireless terminal MS of a new standard. It is a block diagram of a configuration example of a radio terminal MS that performs reception processing. It is a figure explaining the slot (Slot) allocated to a radio | wireless resource. It is a figure which shows the data transfer amount per slot. It is the example of preparation of the allocation message which shows the example which efficiency improves. It is a figure which shows the production | generation / transmission flowchart of the allocation message in radio | wireless base station BS. It is a figure which shows the highest efficiency burst profile which can be used at the time of transmission of allocation information.

Examples according to the present invention will be described below.
[First embodiment] Coexistence of 16e wireless terminal and 16m wireless terminal (Downlink
Map):
The radio base station BS determines how many radio resources are allocated to which radio terminal MS for each radio frame (for example, 5 ms) according to the scheduler, and uses the information as a DL-MAP message 102 / UL-MAP message 103, etc. Store in and send.

  In the present embodiment, the downlink from the radio base station BS to the radio terminal MS will be described, but the uplink in the reverse direction can be implemented in the same manner.

  FIG. 11 shows a flowchart for generating and transmitting an allocation message in the radio base station BS according to the present invention.

  The radio base station BS selects a radio terminal MS that is a radio resource allocation target at the radio resource allocation timing based on the scheduler (steps S1 and Y). At this time, for example, the radio terminal MS having high priority traffic is preferentially selected based on the registration information of the radio terminal.

  For example, when the wireless terminal MS is connected to the wireless base station BS, the wireless terminal registration information is notified from the wireless terminal to the wireless base station BS and registered.

  Then, the required byte amount for the wireless terminal MS selected based on the requested traffic amount is determined (step S2).

  Next, the selected wireless terminal MS is classified into a conventional standard group (referred to as a first wireless terminal group for convenience) and a new standard group (referred to as a second wireless terminal group for convenience) (step S3).

  The conventional standard group, that is, the first wireless terminal group refers to a group of wireless terminals that can receive allocation control information with only one type of burst profile. That is, the wireless terminal MS of the conventional standard group is a wireless terminal that cannot receive the allocation information of the common information and the individual allocation information with different burst profiles.

  On the other hand, the new standard group, that is, the second wireless terminal group means a wireless terminal MS that can receive common information allocation information and individual allocation information in different burst profiles.

  After classifying the wireless terminal MS into a conventional standard group and a new standard group, the wireless terminal MS is further subdivided for each burst profile used for communication (step S4).

  At this time, the burst profile to be used depends on the radio channel state between the radio base station BS and the radio terminal MS. For example, radio channel state information (for example, carrier to interference and noise ratio (CINR)) measured by the radio terminal MS and fed back to the radio base station BS, or a radio channel measured by the radio base station BS itself Based on the state information, the radio base station BS determines the burst profile of each radio terminal MS.

FIG. 12 shows an example of a correspondence table of burst profiles that support the inter-carrier interference noise ratio CINR, which is radio channel state information. For example, when the inter-carrier interference / noise ratio CINR is in the range of X3 to X4, 16QAM
Communication is possible at 1/2.

  Returning to FIG. 11, the required byte amount required for each subgroup represented by the combination of the terminal type and the burst profile is obtained as the sum of the required byte amounts of the radio terminals MS included in the subgroup, and the allocation information MAP-IE message is obtained. Is generated (step S5).

The allocation information includes radio resource information (symbol used: Symbol,
Subchannel) and the identifier of the radio terminal MS are included.

  The radio resource allocation amount is determined by the required byte amount and the burst profile to be used. For example, when 100 bytes of data are considered to be transmitted with QPSK 1/2 and 16QAM 1/2, 16QAM 1/2 is twice as efficient as QPSK 1/2. Half is enough.

  Next, according to the allocation message generation table, an allocation message including allocation information of the radio terminal MS to which radio resources are allocated, that is, a DL-MAP message 102 is generated (step S6).

  FIG. 13 shows an example of the allocation message generation table. In the table of FIG. 6, a DL-MAP message 102 (FIG. 13, A) is a message that can be received by the conventional standard radio terminal MS and the new standard radio terminal MS.

  The DL-MAP message 102 includes a. Common information, b. Allocation information of radio resources used for communication with the radio terminal MS of the conventional standard, c. It includes allocation information of radio resources used for communication with a new standard radio terminal MS communicating with the same burst profile as this message. In addition, among allocation information messages (DL-MAPv2 messages) for new standard radio terminals MS, which will be described later, allocation information on radio resources used for transmission of some allocation information messages (DL-MAPv2 messages) can be included. .

D. The allocation information message (DL-MAPv2 message) for the new standard radio terminal MS is also used to transmit another DL-MAPv2 message that is transmitted with a burst profile more efficient than the burst profile used for its own transmission. Allocation information of the radio resources to be used can be included. That is, in the example of the table of FIG.
DL-MAP message (A) transmitted in 1/2 includes the radio resource information of DL-MAPv2 message # 1 (B) transmitted in 16QAM 1/2, and DL-MAPv2 message # 1 (B) 64QAM
The example includes the radio resource information of DL-MAPv2 message # 2 (C) transmitted at 1/2.

  In this way, by transmitting the transmission radio resource information of the allocation information message with a more efficient burst profile, it is possible to further promote the effective use of radio resources (step S7: FIG. 11).

  Further, in FIG. 13, DL-MAPv2 message # 1 (B) and DL-MAPv2 message # 2 (C) are messages each including allocation information of radio resources addressed to a new standard radio terminal.

  For example, the DL-MAPv2 message # 1 (B) is a message including radio resource allocation information of the radio terminal MS that uses 16QAM (including combinations of various encoding schemes and encoding rates) for communication. Similarly, DL-MAPv2 message # 2 (C) is a message including radio resource allocation information of a radio terminal that uses 64QAM (including combinations of various encoding schemes and encoding rates) for communication.

  In the example of the table of FIG. 13, the allocation information using the same modulation method is stored and transmitted in one message for the allocation information of the radio resource for the new standard radio terminal MS. However, assignment information using different modulation schemes can also be included.

  Further, the burst profile used for message transmission may be a robust burst profile than the burst profile of the allocation information included in the message, and the probability that the message is normally received may be improved.

For example, a message containing allocation information specified as 16QAM
It may be transmitted with a 3/4 burst profile.

    FIG. 14 shows an example of transmission of an allocation message in the downlink subframe. In the figure, a frame control header (FCH) is positioned at the head of the frame with a fixed size, and the modulation method and encoding method are also fixed.

  Therefore, the radio terminal MS can acquire information by detecting the beginning of the frame by demodulating the preamble, demodulating and decoding the frame control header (FCH). The frame control header (FCH) includes radio resource information (radio resource and burst profile) for transmitting the DL-MAP message 102.

  Next, a block configuration example of the radio base station BS that executes the processing according to the present invention will be described with reference to FIG.

  In FIG. 15, the radio base station BS has an antenna 200 for transmitting and receiving radio signals to and from the radio terminal MS. The duplexer 201 is for sharing the antenna 200 in the transmission / reception system.

  As a receiving system, a receiving unit 210 to which the reception output of the duplexer 201 is input, a demodulating unit 211 that demodulates the received signal, a decoding unit 212 that decodes the demodulated received signal, extracts control data from the decoded data, and determines a burst profile A packet that is supplied to the unit 203 and packetized from the control data extracting unit 213 that transfers other data such as user data to the packet reproducing unit 214 and transferred to the network (NW) interface unit 204 A playback unit 214 is included.

  The NW interface unit 204 is an interface with a routing device (not shown) (device connected to a plurality of radio base stations and controlling the route of data such as packet data) (here, packet communication is performed). It is an interface part which forms.

  On the other hand, as a transmission system, packet data received from the NW interface unit 204 is guided to the packet identification unit 220.

  The packet identification unit 220 stores the packet data received from the NW interface unit 204 in the packet buffer unit 221. At the same time, the IP address included in the packet data is identified, and the destination wireless terminal MS is identified based on the IP address data (for example, the correspondence between the IP address data and the ID of the wireless terminal MS is stored, and the corresponding wireless terminal MS ID).

Next, QoS (Quality) corresponding to the ID of the wireless terminal MS
of Service: Similarly, information is stored corresponding to the ID), and a bandwidth allocation request is made by giving the MAP information generating unit 222 the ID, QoS information, and data size.

  Upon receiving the bandwidth allocation request from the packet identification unit 220, the MAP information generation unit 222 selects the wireless terminal MS to which the bandwidth is allocated according to the QOS, and determines the number of data bytes that can be transmitted (step S2: FIG. 11). .

  Then, the selected wireless terminals MS are grouped according to a conventional standard or a new standard (step S3: FIG. 11). Further, the new standard wireless terminal MS is subgrouped by the burst profile used for communication based on the information of the wireless terminal management table held in the MAP information generation unit 222 (step S4: FIG. 11).

  FIG. 16 is an example of a wireless terminal management table. A burst profile is stored in association with the new standard wireless terminal MS.

  Next, for each terminal type and burst profile, necessary radio resources are calculated from the total number of data bytes, and allocation information (MAP-IE) for designating a transmission area and a burst profile is generated (step S5: FIG. 11). .

  Then, as shown in FIG. 14, MAP data including allocation information is generated according to the allocation message generation table, and the PDU generation unit 223 is instructed to form a radio frame according to the MAP data (step S6: FIG. 11).

  The PDU generation unit 223 generates PDU data so that MAP data and transmission data are stored in each region of the radio frame formed with reference to the synchronization signal (preamble), and sends the PDU data to the encoding unit 224.

  The encoding unit 224, the modulation unit 225, and the transmission unit 226 sequentially modulate PDU data after performing encoding processing such as error correction encoding, and transmit the PDU data as a radio signal from the transmission unit 226 via the antenna 200.

  The radio base station BS further includes a control unit 203, and the control unit 203 includes a burst profile determination unit 203A. The control unit 203 is connected to the storage unit 203.

  The storage unit 202 stores various data to be stored by the radio base station BS. For example, the capability information determined for each wireless terminal is stored. The storage unit 202 is used to manage and store the resource usage status of the radio base station BS.

  The control unit 203 determines a burst profile used for communication with the radio terminal MS from the carrier-to-interference noise ratio (CINR) measurement value fed back from the radio terminal MS with reference to the burst profile table (FIG. 12), Manage with MS management table.

  An example of the MS management table according to FIG. 16 is shown. A burst profile is set for the wireless terminal MS.

  FIG. 17 is a diagram showing a MAP message reception process flow in the conventional standard radio terminal MS and the new standard radio terminal MS according to the present invention.

  17A shows a MAP message reception processing flow in a conventional standard wireless terminal MS, for example, as the first group of wireless terminals MS. When the conventional radio terminal MS receives the DL-MAP message 102 (step S10, Y), it analyzes the message (step S11).

  By analyzing the DL-MAP message 102, common information is received (step S12). Further, if the first wireless terminal group includes individual allocation information addressed to itself (step S13, Y), the allocation information is Demodulate and decode the radio signal of the instructed burst profile and radio resource, and acquire user data addressed to itself (step S14).

  On the other hand, FIG. 17B shows a MAP message reception process flow in a new standard radio terminal MS, for example, as the second group of radio terminals MS.

  When receiving the DL-MAP message 102 (step S10, Y), the wireless terminal MS of the second wireless terminal group analyzes the message (step S11), as in the process of FIG. 17A. By analyzing the DL-MAP message 102, common information is received (step S12). Further, if the second wireless terminal group includes individual allocation information addressed to itself (step S13, Y), the allocation information is Demodulate and decode the radio signal of the instructed burst profile and radio resource, and acquire user data addressed to itself (step S14).

  On the other hand, if the individual allocation information addressed to itself is not included in step S13 (step S13, N), the allocation of radio resources including the DL-MAPv2 message corresponding to the new standard radio terminal in the DL-MAP message 102 The presence or absence of information is confirmed (step S15).

  When the allocation information of the radio resource including the DL-MAPv2 message is included, the DL-MAPv2 message is acquired by demodulating and decoding the radio signal of the burst profile and the radio resource indicated by the allocation information.

  Then, the DL-MAPv2 message is analyzed (step S16), and when the individual allocation information addressed to itself is included, the burst profile indicated by the allocation information and the radio signal of the radio resource are demodulated and decoded, and the user addressed to itself Get the data.

  If the DL-MAP message 102 does not include the individual allocation information addressed to itself, whether to acquire the allocation information addressed to itself to confirm the presence / absence of radio resource allocation information including the DL-MAPv2 message in the message Repeat until there are no unparsed DL-MAPv2 messages.

  FIG. 18 is a block diagram illustrating a configuration example of the wireless terminal MS that performs the reception process.

  The radio terminal MS has an antenna 300 for transmitting / receiving radio signals to / from the radio base station BS, and a duplexer 301 for sharing the antenna 300 in the transmission / reception system.

  Further, the receiving system includes a receiving unit 310, a demodulating unit 311 for demodulating the received signal, a decoding unit 312 for decoding the demodulated received signal, and a control message extracting unit 313 for extracting control data from the decoded data.

  The control message extraction unit 313 provides the extracted MAP data to the MAP information analysis unit 304, and other control data is transferred to the control unit 303, and other data such as user data is transferred to the data processing unit 302 (step). S10, FIG. 17).

  The MAP information analysis unit 304 analyzes the MAP data received from the radio base station BS, and gives the analysis result to the control unit 303 (step S11, FIG. 17).

  That is, the control unit 303 is notified of various data transmission / reception timings, subchannels, and burst profiles. At this time, the radio terminal MS of the new standard finds different radio burst profiles until it finds radio resource allocation information addressed to itself (steps S13, Y, step S14, FIG. 17) or completes the analysis of all MAP data. The demodulation, decoding and analysis of the MAP data received at step S15 are repeated (step S15, FIG. 17).

  The data processing unit 302 performs display processing of various data included in received data, audio output processing, and the like. Further, the data processing unit 302 provides user data desired to be transmitted to the communication destination device to the packet buffer unit 320.

  The packet buffer unit 320 outputs the stored data to the encoding unit 321 so that the transmission data from the data processing unit 302 can be transmitted with the transmission timing, subchannel, and burst profile specified by the MAP data.

The encoding unit 321 and the modulation unit 322 code the transmission data under the control of the control unit 303 so as to transmit the transmission data from the packet buffer unit 320 with the transmission timing, subchannel, and burst profile specified by the MAP information. The radio signal is transmitted via the antenna 300.
[Second Embodiment] Considering the number of slots:
In OFDMA of IEEE 802.16, radio resources are allocated in units called slots.

  FIG. 19 shows an example of a slot. In the example shown in the figure, a slot is defined by 24 data subcarriers (further 4 pilot subcarriers) and two OFDMA symbols in the frequency direction f.

  Therefore, the data transfer amount per slot is as shown in FIG.

As described above, radio resources are allocated in units of slots. For example, QPSK
When the DL-MAP message 102 transmitted by 1/2 is 31 bytes (Bytes), the data amount per slot of PSK 1/2 is 6 bytes as shown in FIG. It will consume 6 slots.

  However, in the sixth slot, only 1 byte is used, and 5 bytes are not used.

  In view of this, the second embodiment further comprises a step of determining in which allocation message the radio resource allocation information for individual radio terminals is stored and transferred according to the number of slots actually used. , Can increase efficiency.

  FIG. 21 is an example of creating an allocation message showing an example of improving efficiency. As shown in the table in the figure, when an allocation message is generated for each wireless terminal type and burst profile of a new standard wireless terminal MS (FIG. 21, A), a total of 9 slots of wireless resources are consumed.

However, here the new standard burst profile = 16QAM
By including 1/2 allocation information in the allocation information transmitted by QPSK 1/2 and including allocation information of BP = 64QAM 1/2 and 3/4 in the allocation message of burst profile = 16QAM 1/2, a total of 8 It becomes possible to reduce the radio resource consumption of the slot (see FIG. 21, B: optimization column).

In the figure, the second allocation message is supposed to be transmitted using burst profile BP = 16QAM 1/2, but since the target wireless terminal of the included allocation information is 16QAM 3/4, burst profile = 16QAM
You can also send a message using 3/4.

  FIG. 22 shows an allocation message generation / transmission flowchart in the radio base station BS according to the second embodiment.

  The radio base station BS selects a radio terminal MS that is a radio resource allocation target at the radio resource allocation timing according to the scheduler (steps S1 and Y). At this time, for example, a wireless terminal having high priority traffic is preferentially selected. Then, the required byte amount for the selected wireless terminal is determined based on the requested traffic amount (step S2).

  Next, the selected wireless terminal is classified into a conventional standard group and a new standard group (step S3). As described above, the conventional standard group indicates a wireless terminal that can receive allocation control information only with one type of burst profile. That is, the wireless terminal cannot receive the allocation information of the common information and the individual allocation information with different burst profiles. On the other hand, a new standard group represents a wireless terminal capable of receiving common information allocation information and individual allocation information in different burst profiles.

  After classifying the radio terminals MS into the conventional / new standard groups, they are further subdivided for each burst profile used for communication (step S4). At this time, the burst profile to be used depends on the radio channel state between the radio base station BS and the radio terminal MS.

  For example, radio channel state information (for example, Carrier to Interference and Noise Ratio (CINR)) measured by the radio terminal MS and fed back to the radio base station BS, or a radio channel measured by the radio base station BS itself Based on the status information, the radio base station BS determines the burst profile of each radio terminal MS.

  The required byte size of each subgroup represented by the combination of terminal type and burst profile is obtained, and the sum of the required byte sizes of the radio terminals MS included in the subgroup is obtained to generate allocation information (MAP-IE) ( Step S5).

  The allocation information includes radio resource information (symbol used: Symbol, subchannel: Subchannel) and an identifier of the radio terminal MS.

  The radio resource allocation amount is determined by the required byte amount and the burst profile to be used. For example, if 100 bytes of data are transmitted using QPSK 1/2 and 16QAM 1/2, 16QAM 1/2 is twice as efficient as QPSK 1/2, so the radio resource used is half. That's it.

 Next, the allocation information is stored in an allocation message (DL-MAP message). At this time, messages are allocated from the allocation information with low efficiency of the burst profile used when transmitting the allocation information.

  That is, if there is allocation information (step S60, N), allocation information to be transmitted with QPSK 1/2 having low transmission efficiency is first stored in the allocation message. Then, the number of slots required for transmitting the allocation message size (number of bytes) by QPSK 1/2 is calculated (step S61).

  If there is free capacity in the last slot (step S62, Y), it is determined whether the allocation information with the lowest efficiency of the highest efficiency burst profile at the time of transmission can be stored in the free area among the allocation information that has not been messaged (Step S63).

  If it can be stored (step S63, Y), it is inserted into the message (step S64), and the same processing is repeated until there is no more free space (step S62, N).

  FIG. 23 shows the highest efficiency burst profile that can be used when transmitting the allocation information. Allocation information addressed to wireless terminals of the existing standard of the first wireless terminal group must be transmitted using QPSK 1/2.

  On the other hand, burst profile (= 16QAM 3/4) allocation information must be transmitted by QPSK 1/2, 16QAM 1/2, or 16QAM 3/4 at the new wireless terminal of the second wireless terminal group. Is possible. Of course, the lower the efficiency of transmission using a burst profile, the stronger the probability that a message will be received normally, and it is more resistant to degradation of the radio channel state.

  Returning to FIG. 22, when all the allocation information is stored in the allocation message, each allocation message is transmitted in a predetermined burst profile (step S7).

  Radio resources for transmitting individual allocation information for new standard radio terminals have slots different from the slot definitions (data, number of pilot subcarriers, number of symbols) shown in FIG. It may be an allocation unit.

 As described above, according to the present invention, radio resources can be allocated by mixing the first group of radio terminals corresponding to the conventional standard and the second group of radio terminals which are new standards, and the radio resources are allocated. Enables effective use of. Therefore, the present invention greatly contributes to the industry.

Claims (11)

In a radio communication system including a radio base station and a plurality of radio terminals, control information including a radio resource used when the radio base station communicates with the radio terminal, a combination of a modulation scheme and a coding scheme, and the radio A method of transmitting from a base station to the wireless terminal,
Based on registration information of the plurality of wireless terminals, a first wireless terminal group capable of receiving the control information only by a combination of a single modulation scheme and encoding scheme, and the control information for a plurality of modulation schemes and encoding Classifying the plurality of wireless terminals into a second wireless terminal group capable of receiving a combination of methods ;
Generating first control information common to the plurality of wireless terminals and second control information specific to each wireless terminal;
Transmitting the first control information and the second control information addressed to wireless terminals belonging to the first wireless terminal group using a combination of the same modulation scheme and encoding scheme;
Transmitting the second control information addressed to the radio terminals belonging to the second radio terminal group in a combination of a modulation scheme and a coding scheme according to a radio channel state between the radio base station and the radio terminal; A control information transmission method characterized by comprising: In claim 1,
The wireless terminal registration information is notified from the corresponding wireless terminal when the wireless terminal connects to the wireless base station. In claim 1,
The first control information and the second control information addressed to the wireless terminals belonging to the first wireless terminal group use a combination of the most inefficient modulation method and encoding method that can be transmitted by the wireless base station. And transmitting the control information. In claim 1,
The first control information and the second control information addressed to the wireless terminals belonging to the first wireless terminal group can be received by all wireless terminals that should receive the second control information specific to the wireless terminal. A method for transmitting control information, wherein transmission is performed using a combination of a modulation scheme and a coding scheme. In claim 1,
Determining in accordance with the prior SL required radio resource amount, a combination of a modulation scheme and coding scheme used when transmitting the second control information,
Transmitting the first control information and the second control information using a determined combination of modulation scheme and encoding scheme;
A method for transmitting control information, comprising: In claim 1,
A step of pre-Symbol first control information and the second wireless terminal to receive the control information to determine a combination of a receivable modulation schemes and coding schemes,
Transmitting the first control information and the second control information using a determined combination of modulation scheme and encoding scheme;
A modulation scheme and a coding scheme that are less efficient than a combination of a modulation scheme and a coding scheme included in the designation information for specifying information on a combination of a radio resource or a modulation scheme and a coding scheme to which the second control information is transmitted Transmitting in a combination of a modulation method and a coding method other than the combination of the most inefficient modulation method and the coding method among the other second control information transmitted in a combination of
A method for transmitting control information, comprising: In radio communications system comprising a plurality of radio terminals end radio base station, a radio resource used when the said radio base station radio terminal communicates, the control information including a combination of a modulation scheme and coding scheme A method in which the wireless terminal receives from the wireless base station,
Based on the registration information of the plurality of wireless terminals , the plurality of wireless terminals can receive the control information from a first wireless terminal group that can receive the control information only by a combination of a single modulation scheme and a coding scheme. It is classified into a second wireless terminal group that can be received by a combination of a plurality of modulation schemes and encoding schemes,
In the wireless terminals of the second wireless terminal group,
Receiving first control information common to the plurality of wireless terminals or second control information specific to each wireless terminal;
Modulation scheme and coding that are less efficient than the combination of the modulation scheme and the coding scheme included in the designation information for the designation information of the combination of the radio resource or the modulation scheme and the coding scheme in which the second control information is transmitted Receiving in a combination of a modulation scheme and a coding scheme other than the combination of the modulation scheme and the coding scheme having the lowest efficiency among the other second control information transmitted in a combination of schemes;
A method of receiving control information, comprising: E Bei a radio base station and a plurality of radio terminals, the radio and the radio resources used when the before and Symbol radio base station radio terminal communicates, the control information including a combination of a modulation scheme and a coding scheme from the radio base station A wireless base station in a wireless system that transmits to a terminal,
Based on registration information of the plurality of wireless terminals, the wireless terminal can receive the control information only by a combination of a single modulation scheme and a coding scheme and a plurality of modulations of the control information. A classification unit that classifies the plurality of wireless terminals into a second wireless terminal group that can be received by a combination of a scheme and a coding scheme ;
A control information generator for generating first control information common to the plurality of wireless terminals and second control information specific to each wireless terminal;
Transmitting the first control information and the second control information addressed to the wireless terminals belonging to the first wireless terminal group using a combination of the same modulation scheme and encoding scheme, and the second wireless terminal group A transmitter that transmits the second control information addressed to the wireless terminal belonging to the wireless terminal in a combination of a modulation scheme and a coding scheme according to a wireless channel state between the wireless base station and the wireless terminal. Radio base station. In claim 8,
A resource amount calculation unit that calculates a required radio resource amount when the previous SL first control information and the second wireless terminal to receive the control information is transmitted with a combination of receivable modulation schemes and coding schemes,
A determining unit that determines a combination of a modulation scheme and a coding scheme to be used when transmitting the second control information according to the required radio resource amount;
A transmission unit for transmitting the first control information and the second control information using a determined combination of a modulation scheme and a coding scheme;
A radio base station characterized by comprising: In claim 8,
A determination unit for pre Symbol first control information and the second wireless terminal to receive the control information to determine a combination of a receivable modulation schemes and coding schemes,
Transmitting the first control information and the second control information using a combination of the determined modulation scheme and encoding scheme;
The radio resource to which the second control information is transmitted or the designation information of the combination of the modulation scheme and the coding scheme is changed to a modulation scheme and a coding scheme that are less efficient than the combination of the modulation scheme and the coding scheme included in the designation information. A transmission unit that transmits in a combination of a modulation method and a coding method other than the combination of the modulation method and the coding method with the lowest efficiency among the other second control information transmitted in combination;
A radio base station characterized by comprising: E Bei a radio base station and a plurality of radio terminals, the radio and the radio resources used when the before and Symbol radio base station radio terminal communicates, the control information including a combination of a modulation scheme and a coding scheme from the radio base station A wireless terminal in a wireless system that transmits to a terminal,
Based on the registration information of the plurality of wireless terminals, the plurality of wireless terminals can receive the control information from a first wireless terminal group that can receive the control information only by a combination of a single modulation scheme and a coding scheme. It is classified into a second wireless terminal group that can be received by a combination of a plurality of modulation schemes and encoding schemes,
In the wireless terminals of the second wireless terminal group,
Receiving first control information common to the plurality of wireless terminals or second control information specific to each wireless terminal;
Modulation scheme and coding scheme that is less efficient than the combination of the modulation scheme and the coding scheme included in the designation information with respect to the designation information of the combination of the radio resource or the modulation scheme and the coding scheme in which the second control information is transmitted A receiving unit that receives a combination of a modulation scheme and a coding scheme other than the combination of the modulation scheme and the coding scheme that are the least efficient among the other second control information transmitted in a combination of
A wireless terminal characterized by comprising:

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