WO2011106927A1

WO2011106927A1 - Base station in wireless communication system based on ofdma and resource allocation method for use thereof

Info

Publication number: WO2011106927A1
Application number: PCT/CN2010/070821
Authority: WO
Inventors: 薛金银; 张�杰; 田军; 周华; 梁生宝
Original assignee: 富士通株式会社
Priority date: 2010-03-02
Filing date: 2010-03-02
Publication date: 2011-09-09
Also published as: CN102742344B; CN102742344A

Abstract

A base station in a wireless communication system based on OFDMA and resource allocation method for use thereof are provided in the present invention. The base station in the wireless communication system based on the OFDMA includes: a resource allocation unit, for allocating allocable resources to data packets to be transmitted in unit of an OFDMA symbol; a control information generating unit, for generating control information indicating the resources allocated to the data packets by the resource allocation unit. With the present invention, the fragmentations of the resource region generated in the resource allocation process of the base station side in the wireless communication system based on the OFDMA can be decreased.

Description

- -

Base station in OFDMA-based wireless communication system and resource allocation method used therein

Technical field

The present invention relates to wireless communication technologies, and more particularly to a base station in an OFDMA-based wireless communication system and a resource allocation method used in a base station in an OFDMA-based wireless communication system.

Background technique

[02] Mobile communication networks are transforming into all-IP networks. Among them, VoIP (voice over IP) services have seen great growth in the past few years. Mobile packet switched networks such as HSPA (High Speed Packet Access) and CDMA2000 lxEV-DO can support voice services more efficiently than circuit switched networks. With the development of mobile networks, new mobile communication standards (for example, WiMAX's IEEE 802.16e/m, 3rd Generation Partnership Project Organization Long Term Evolution Communication Standard (3GPP / LTE), etc.) will use more technologies. To increase the capacity of VoIP. In 3GPP's High Speed Packet Access (HSPA) technical specification (R4/5/6〃), control signaling overhead is reduced and transmission efficiency of VoIP packets is improved by compression and packet bundling techniques for IP headers. The 802.16 standard improves VoIP capacity by reducing signaling overhead.

[03] The next generation mobile communication system is based on Orthogonal Frequency Division Multiple Access (OFDMA) technology. Taking the IEEE 802.16 standard as an example, a typical data format of an air interface between a base station and a mobile terminal is shown in FIG. The data transmitted at one time consists of several data frames (n+1 in FIG. 1, n is a positive integer), each data frame is divided into 8 subframes (SF0 to SF7), and each subframe is composed of 6 OFDM symbols. (For example, SF1 in Fig. 1 is composed of 6 OFDM symbols), and each symbol includes several frequency domain subcarriers (e.g., la to lx in Fig. 1).

[04] As can be seen from Figure 1, the assignable data resource area is a time-frequency two-dimensional interval, and the time domain is composed of OFDMA symbols (or data frames), and the frequency domain is OFDMA subcarriers. The data frame length supported by the 802.16 protocol is 1.25/2.5/5/10/20 milliseconds, and the OFDMA subcarriers are 256/512/1024/2048.

[05] In a wireless communication system, resource allocation of the downlink is performed at the base station side.

[06] The data transmission and reception of the base station is in units of data frames. First, the base station determines the VoIP data packet to be sent in the current frame and the available resource size, and then selects one data packet according to a certain scheduling algorithm. - - Coded modulation according to its corresponding user channel quality and placed in the data area, corresponding to generating a control message such as MAP (Mobile Application Part) message. The MAP message contains the packet size and encoding format message as well as the destination terminal message. When the resource area of the assignable downlink frame data has no space, the resource allocation of the current frame ends.

[07] In the 802.16 standard, the VoIP capacity of the system is inversely related to the associated overhead. Mobile communication is important for VoIP applications due to frequent transmissions and small VoIP packets. Typical VoIP packets are divided into Active Packet and Silence Packet, which are 44 bytes (Bytes) and 18 bytes respectively. Since 802.16e systems use dynamic scheduling to support VoIP, most of the overhead associated with VoIP traffic occurs in MAP messages. If each packet carries a control message such as a DL-MAP allocation message (approximately 60 bits), the overhead of the control information occupies a large amount of downstream frame resources, limiting the capacity of the VoIP.

[08] Table 1 shows the composition of a typical control information (i.e., downlink MAP-IE message) and the corresponding number of bits.

Table 1 Contents of DL-MAP-IE

[09] To reduce these overheads, 802.16 Rev. 2 introduced the concept of Persistent Allocation. At this time, periodically occurring resources will be sent to the user once or infrequently. Figure 4 shows a schematic diagram of the principle of persistent resource allocation, which is a 5 ms frame structure based on 802.16. In FIG. 4, for each data frame, the position of the data area addressed to a certain terminal in the downlink subframe is always unchanged, as shown by the shaded portion 401 in FIG. - - You can reduce the position information in the control information such as DL-MAP. For example, the time/frequency domain symbol number and start position information are omitted in the control information. For VoIP traffic, this continuous resource allocation can reduce control information overhead by 40-50%, which can increase the capacity of two-way VoIP by 15-20%. The concept of continuous resource allocation has been adopted in the 3G LTE (Long Term Evolution) standard. If the modulation and coding methods are also unchanged, the length of the control information can be further reduced.

[10] A typical set of system parameters for the 802.16 protocol for VoIP services is as follows: The time domain data frame is 5 milliseconds, the length of each subframe is 0.67 milliseconds, and one frame of data includes 48 OFDMA symbols, and each OFDMA symbol is at The frequency domain contains 1024 subcarriers. In the eight subframes of one frame of data, the uplink and downlink subframes are allocated as 5/3 or 4/4 (ie, 5 uplink subframes, 3 downlink subframes, or 4 uplink subframes, and 4 downlink subframes). . Each subframe includes 6 OFDMA symbols. The frequency domain parameters are: 1024 subcarriers, except the pilot and protection subcarriers. The number of subcarriers that can be used to allocate data is 768, and each 18 subcarriers form one subchannel, for a total of 48 frequency domain subchannels. The downlink assignable minimum data unit (RB) is 108 OFDMA symbols, including 6 symbols in the time domain and 18 subcarriers in the frequency domain.

[11] Further, 802.16m introduces a method of group resource allocation (Group Resource Allocation), that is, a group (or group) of VoIP packets having the same data resource block to reduce the overhead of control information.

[12] At this time, the same modulation coding format or the same size data block occupies a time-frequency continuous data area, as shown in Fig. 5. The assignable resource area 501 is divided into a number of different shaded areas (groups) representing data of different modulation and coding formats (MCS), respectively. 502 denotes a second MCS group, and a square in the group represents a data packet corresponding to a control information. Since the MCS information in the group can be shared, the overhead of the control information can be reduced by the packet resource allocation method.

[13] However, the above methods all have the problem of fragmentation of resource areas.

[14] Specifically, in the 802.16 d/e standard, data provided by a base station to a terminal is allocated in units of a minimum data unit (ie, a resource block, RB for short). Even if there is less than one RB, the terminal is assigned an RB and corresponding control information. On the other hand, since the size of the resource block is related to the modulation and coding mode, there may be a case where the data length is less than an integral multiple of the minimum resource unit in the data area, thereby causing fragmentation of the resource area.

[15] For example, as shown in FIG. 5, resource blocks RB1 to RB4 are assigned to the first number in group 1. - - According to the packet, resource blocks RB5 to RB8 are assigned to the second packet in group 1, resource blocks RB9 to RB12 are assigned to the third packet in group 1, and so on. Since the size of the data packet is not an integer multiple of the resource block size, as shown in FIG. 5, some resource regions in the resource blocks RB4, RB8, and RB12 are wasted, which is referred to herein as a fragmentation phenomenon of the resource region.

[16] For another example, for QPSK (Quadrature Phase Shift Keying) -1/2 coding, the active packet length is 352 OFDMA symbols, and the quiet state packet length is 144 OFDMA symbols. For 16QAM (Quadrature Amplitude Modulation) - 1/2 encoding, the number of data symbols is 176 and 72, respectively. A typical minimum data unit (i.e., resource block RB) is 6 time domain symbols X 18 frequency domain subcarriers = 108 modulation symbols. At this time, an active state data packet of QPSK-1/2 occupies 4 resource blocks (432 modulation symbols), and has a fragmentation interval of 80 modulation symbols, as shown by hatched portion 506 in FIG. A QPSK-1/2 silent state packet occupies 2 resource blocks, and the fragment size is 72 symbols. The 64QAM-l/2 active state packet and the silent state packet occupy 2/1 resource blocks, respectively, and the fragment size is 40/36 symbols. For other coded modulation methods, fragmentation may exist as long as the packet size is not an integer multiple of RB.

[17] Table 2 shows the fragment size (RB number and number of fragment bits) corresponding to the MCS set of IEEE80.16e.

Fragment area size corresponding to the MCS set of 802.16e

MCS (RB number) fragment bit number (RB number) fragment bit number

(active state) (silent state)

BPSK-1/6 (4) 80 (2) 72

BPSK-1/4 (2) 40 (1) 36

BPSK-1/2 (2) 40 (1) 36

QPSK-1/2 (4) 80 (2) 72

QPSK-3/4 (2) 40 (1) 36

16QAM-1/2 (2) 40 (1) 36

16QAM-3/4 (2) 40 (1) 36

64QAM-1/2 (4) 80 (2) 72

64QAM-2/3 (2) 40 (1) 36

64QAM-3/4 (4) 80 (2) 72

64QAM-5/6 (2) 40 (1) 36 - -

[18] For multi-antenna systems, the calculation of the fragmentation area varies depending on how the multi-antenna is transmitted. For example, for a space frequency code (SFBC), the fragment area is the same as the single antenna system, and for space division multiple access (SM) and precoded transmission modes, the fragmentation is calculated corresponding to the actual antenna data block. For example, in the spatial division multiple access mode of two transmit antennas, in the QPSK-1/2 coding mode, the number of active data packets and silent data packets per antenna is 176/72, and the corresponding number of fragment symbols is 40/36. .

[19] In summary, the resource allocation scheme currently used in a base station of an OFDM-based wireless communication system focuses only on saving overhead by reducing the length of control information such as DL-MAP information, without considering The impact of unused fragmentation in the resource area on resource occupancy.

[20] Therefore, there is still a need for a base station capable of reducing resource area fragmentation generated in a resource allocation process of a base station side in an OFDMA-based wireless communication system and/or a resource allocation method used in the base station.

[21] The following is a list of references to the present invention, the disclosure of which is hereby incorporated by reference in its entirety in its entirety in its entirety.

[22] Patent Document 1: "Signaling Support for Grouping Data and Voice Users to Share the Radio Resources in Wireless Systems" by Wu Tao et al. (US Patent Application US 20080228878 Al);

[23] Patent Document 2: "Resource Allocation and Signaling for Group Scheduling in Wireless Communications" by Wang Jin et al. (US Patent Application US 20080225783 Al);

[24] Patent Document 3: "VoIP Group Resource Management" by Khandekar Aamod et al. (US Patent Application US 20080062178 Al);

[25] Patent Document 4: "Method and system for sharing resources in a wireless communication network" by Lu Jianmin et al. (U.S. Patent Application US 20080095071 Al);

[26] Patent Document 5: "Method and system for allocating resources in a communication system" by KANG Hee-Won et al. (U.S. Patent Application US 20090122754 Al);

[27] Patent Document 6: "Method and system for processing for Group Resource Allocation" by He Xiao Md et al. (US Patent Application US 20080062936 Al);

[28] Patent Document 7: Novak Robert et al. "Multiplexing schemes for - -

OFDMA" (US Patent Application US 20090022098 Al);

[29] Non-Patent Document 1: IEEE Std. 802.16-2004: IEEE Standard for Local and metropolitan area networks - Part 16: Air Interface for Fixed Broadband Wireless Access Systems, June 2004;

[30] Non-Patent Document 2: IEEE Std. 802.16e-2005, IEEE Standard for Local and metropolitan area networks - Part 16: Air Interface for Fixed and Mobile Broadband Wireless Access Systems - Amendment 2: Physical and Medium Access Control Layers for Combined Fixed and Mobile Operation in Licensed Bands, and IEEE Std. 802.16-2004/Corl-2005, Corrigendum 1, December 2005;

[31] Non-Patent Document 3: "VoIP support using group resource allocation based on the UMB system" by McBeath, S et al., Communications Magazine, IEEE, Vol. 46, pp. 114-120, January 2008;

[32] Non-Patent Document 4: "Principle and Performance of Semi-Persistent Scheduling for VoIP in LTE System" by Dajie Jiang et al., WiCom 2007, pp. 2861-2864.

Summary of the invention

A brief summary of the invention is set forth below to provide a basic understanding of certain aspects of the invention. It should be understood that this summary is not an exhaustive overview of the invention. It is not intended to identify key or critical aspects of the invention, and is not intended to limit the scope of the invention. Its purpose is to present some concepts in a simplified form as a pre-

At least one object of the present invention is to provide a base station in an OFDMA-based wireless communication system, and a resource allocation method used in a base station in an OFDMA-based wireless communication system, which is capable of overcoming at least some of the disadvantages of the prior art described above. And insufficient to reduce the resource region fragmentation generated in the resource allocation process on the base station side in the OFDMA-based wireless communication system.

[35] In order to achieve the above object, according to an embodiment of the present invention, a base station in an OFDMA-based wireless communication system is provided, including: a resource allocation unit, configured to allocate an allocatable resource to an OFDMA symbol. a data packet to be transmitted; and a control information generating unit for generating a control letter indicating a resource allocated to the data packet by the resource allocation unit [36] The base station may further include: a grouping unit, configured to group the data packets to be transmitted.

[37] In the base station, the grouping unit may be configured to: divide, in the data packet to be transmitted, a data packet to be modulated using the same modulation manner into the same group; or in the data packet to be transmitted, The modulation mode to be used is modulated and the packets of the same size are divided into the same group.

[38] In the base station, the resource allocation unit may be configured to: continuously allocate the allocatable resources in units of OFDMA symbols to each data packet in each group divided by the grouping unit; or The resources are continuously allocated to each group divided by the grouping unit in units of resource block sizes specified in the wireless communication system, and resources to be allocated to each group are continuously allocated in units of OFDMA symbols to The packets in this group.

[39] in the base station, the grouping unit may be configured to divide, in the data packet to be transmitted, packets that are the same size after being modulated according to a modulation mode to be used into the same group; and modulation of the resource The modulation scheme with the lowest code rate in the mode is determined as a modulation scheme to be used for each data packet in the group, and the assignable resources are continuously allocated to the packet by the resource block size specified in the wireless communication system. Each group of cells is divided, and resources allocated to each group are continuously allocated to data packets in the group in units of OFDMA symbols.

[40] In the base station, the control information may include information indicating that the resource allocation unit is a start position of a resource allocated by each group divided by the grouping unit, and indicating a packet included in each group Number of information, and modulation method information.

[41] In the base station, the data packet to be transmitted may include a data packet to be retransmitted.

[42] In the base station, the wireless communication system can be based on the IEEE 802.16 protocol and the time division duplex communication mode, and the control information can be included in the downlink frame channel assignment message in the downlink frame. Alternatively, in the base station, the wireless communication system may be based on an IEEE 802.16 protocol and a frequency division duplex communication mode, and the control information may be included in a signaling message transmitted using a dedicated frequency band. Alternatively, in the base station, the wireless communication system may organize long term evolution communication standards based on the 3rd Generation Partnership Project.

[43] In order to achieve the above object, according to another embodiment of the present invention, a resource allocation method used in a base station in an OFDMA-based wireless communication system is provided, including: allocable resources in units of OFDMA symbols Assigned to the data packet to be transmitted; and generates control information indicating the resource assigned to the data packet. - -

[44] The resource allocation method may further include: grouping the data packets to be transmitted.

[45] In the resource allocation method, ^ grouping the data packets to be transmitted may include: 1

The same packets are divided into the same group. , ^P w port,

[46] In the resource allocation method, allocating the allocatable resources in units of OFDMA symbols to the data packet to be transmitted may include: continuously assigning the assignable resources to the divided each in units of OFDMA symbols Each data packet in the group; or continuously allocates the assignable resources to each of the divided groups in units of resource block sizes specified in the wireless communication system, and the resources to be allocated to each group The OFDMA symbols are continuously allocated to the packets in the group in units.

[47] In the resource allocation method, grouping the data packets to be transmitted may include dividing, in the data packets to be transmitted, packets having the same size after being modulated according to a modulation mode to be used to be the same And assigning the allocatable resources to the data packet to be transmitted in units of OFDMA symbols may include: a modulation scheme having the lowest code rate among the modulation modes to be used for the data packets in each group to be divided Determining, as a modulation scheme to be used for each data packet in the group, continuously assigning the assignable resources to each of the divided groups in units of resource block sizes specified in the wireless communication system, and will be allocated The resources for each group are continuously allocated to the packets in the group in units of OFDMA symbols.

[48] In the resource allocation method, the control information may include information indicating a start position of a resource allocated for each of the divided groups, information indicating a number of data packets included in each group, and Modulation method information.

[49] In the resource allocation method, the data packet to be transmitted may include a data packet to be retransmitted.

[50] In the resource allocation method, the wireless communication system can be based on an IEEE 802.16 protocol and a time division duplex communication method, and the control information can be included in a downlink frame channel allocation message in a downlink frame. Alternatively, in the resource allocation method, the wireless communication system may be based on an IEEE 802.16 protocol and a frequency division duplex communication method, and the control information may be included in a signaling message transmitted using a dedicated frequency band. Alternatively, in the resource allocation method, the wireless communication system may organize a long term evolution communication standard based on a third generation partnership plan.

According to an embodiment of the present invention, resources that are to be allocated are allocated in units of OFDMA symbols in units of OFDMA symbols, instead of resource allocation in units of resource blocks (RBs) in the prior art, Preventing the length of the data packet from being a resource block during the resource allocation process - An integer multiple of the length causes the resource region fragmentation to occur, thereby being able to reduce the resource region fragmentation generated in the resource allocation process on the base station side in the OFDMA-based wireless communication system.

These and other advantages of the present invention will be more apparent from the following detailed description of the preferred embodiments of the invention.

DRAWINGS

The invention may be better understood by referring to the following description in conjunction with the drawings, wherein the same or similar reference numerals are used throughout the drawings. The drawings, which are included in the specification, and in the claims In the drawing:

[54] FIG. 1 shows a typical data format of an air interface between a base station and a mobile terminal;

[55] Figure 2 shows a schematic diagram of an 802.16 frame structure in TDD (Time Division Duplex) mode;

[56] FIG. 3 shows a schematic diagram of a resource mapping manner;

[57] FIG. 4 is a schematic diagram showing the principle of persistent resource allocation in the prior art;

[58] FIG. 5 is a schematic diagram showing the principle of packet resource allocation in the prior art;

6 is a schematic diagram of a base station in an OFDMA-based wireless communication system according to Embodiment 1 of the present invention;

7 is a schematic diagram showing a base station in an OFDMA-based wireless communication system according to Embodiment 2 of the present invention;

[61] FIG. 8 is a schematic diagram showing a resource allocation manner of a resource allocation unit according to an example of Embodiment 2 of the present invention;

[62] FIG. 9 is a schematic diagram showing a resource allocation manner of a resource allocation unit according to another example of Embodiment 2 of the present invention;

FIG. 10 is a schematic diagram showing a resource allocation manner of a resource allocation unit according to still another example of Embodiment 2 of the present invention; FIG.

FIG. 11 is a schematic diagram showing grouping of retransmitted data packets according to Embodiment 2 of the present invention; FIG.

12 is a schematic diagram showing a resource allocation area according to an embodiment of the present invention;

FIG. 13 is a schematic diagram showing a continuous distribution manner of data packets according to Embodiment 2 of the present invention. - - Figure;

[67] FIG. 14 is a diagram showing an example of content of control information according to an embodiment of the present invention;

15 is a flowchart showing a resource allocation method used in a base station in an OFDMA-based wireless communication system according to Embodiment 3 of the present invention;

16 shows a flowchart of a resource allocation method used in a base station in an OFDMA-based wireless communication system according to Embodiment 4 of the present invention.

The elements in the figures are illustrated for simplicity and clarity and are not necessarily to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements in order to facilitate an understanding of the embodiments of the invention.

detailed description

Exemplary embodiments of the present invention will be described in detail below with reference to the accompanying drawings. For the sake of clarity and conciseness, not all features of an actual implementation are described in the specification. However, it should be understood that many implementation-specific decisions must be made in the development of any such practical embodiment in order to achieve the developer's specific objectives, for example, compliance with system and business related constraints, and these Restrictions may vary from implementation to implementation. In addition, it should also be understood that while development work can be very complex and time consuming, such development work is only a routine task for those skilled in the art having the benefit of the disclosure.

[72] It is also to be noted that in order to avoid obscuring the invention by unnecessary detail, only the device structure and/or processing closely related to the solution according to the invention is described in the drawings and the description. The steps and the representations and descriptions of the components and processes known to those of ordinary skill in the art that are not relevant to the present invention are omitted.

For example, the present invention mainly relates to a base station in an OFDMA-based wireless communication system and a resource allocation method used in the base station. Therefore, the selection of the modulation and coding scheme of the base station side as described above, the modulation and coding process, the scheduling algorithm, and the wireless data transceiving process as known to those skilled in the art having little relationship with the present invention are omitted herein. A description of the process of ranging, synchronization, and decoding, but only a description of the resource allocation process.

6 shows a schematic diagram of a base station 600 in an OFDMA-based wireless communication system according to an embodiment of the present invention.

[75] As shown in FIG. 6, the base station 600 in the OFDMA-based wireless communication system includes resources. - a source allocation unit 601 and a control information generating unit 602.

[76] The resource allocation unit 601 is configured to allocate an allocatable resource in units of OFDMA symbols to a packet to be transmitted.

[77] As described above, the resource allocation method of the prior art allocates resources in units of resource blocks (RBs), and the resource allocation unit 601 of the present embodiment allocates resources in units of OFDMA symbols. Since the packet length is an integer multiple of the OFDMA symbol, allocating resources in units of OFDMA symbols can prevent fragmentation of resource regions due to the packet length being not an integer multiple of the resource block length.

[78] For example, when the present embodiment is applied to a VoIP service, the capacity of the VoIP service can be improved because the resource area fragmentation generated in the resource allocation process is reduced.

It should be understood by those skilled in the art that the present embodiment is not limited to the VoIP service, and the base station provided by the embodiment may be used for resource allocation as long as the service has a fixed data packet length.

The control information generating unit 602 is configured to generate control information indicating the resource allocated to the data packet by the resource allocating unit 601.

It should be understood by those skilled in the art that the known control information format and the like used by the control information generating unit 602 when generating the control information can be flexibly selected according to the requirements of the actual application, which should be claimed in the present invention. Within the spirit and scope. For example, the control information may include a start address of a resource allocated to the data packet by the resource allocation unit 601, a modulation scheme corresponding to the data packet, and the like.

Therefore, for the sake of brevity of the description, the specific control information format used by the control information generating unit 602 in generating the control information will not be described in detail herein.

As can be seen from the above, the base station 600 in the OFDMA-based wireless communication system according to the first embodiment of the present invention allocates the resources that can be allocated to the transmission to be transmitted in units of OFDMA symbols.

The resource region fragmentation is caused by the multiple, so that the resource region fragmentation generated in the resource allocation process on the base station 600 side in the OFDMA-based wireless communication system can be reduced.

[84] Optionally, in this embodiment, the data packet to be transmitted may include a data packet to be retransmitted. That is to say, for retransmitting a data packet, resources can be allocated in units of OFDMA symbols as described above. - -

[85] Optionally, in this embodiment, the wireless communication system may be based on an IEEE 802.16 protocol and a time division duplex communication mode, and the control information may be included in a downlink frame channel assignment message in a downlink frame.

[86] Alternatively, in the embodiment, the wireless communication system may be based on the IEEE 802.16 protocol and the frequency division duplex communication mode, and the control information may be included in a signaling message transmitted using a dedicated frequency band.

[87] Alternatively, in the present embodiment, the wireless communication system may organize a Long Term Evolution Communication (3GPP LTE) standard based on a third generation partnership plan.

[88] The following briefly describes and describes the duplex communication method and frame structure when the wireless communication system is based on the IEEE 802.16 protocol.

[89] The 802.16 protocol supports two types of duplex communication: TDD (Time Division Duplex) and FDD (Frequency Division Duplex). In TDD mode, a data frame is divided into an uplink frame and a downlink frame in the time domain. In the FDD mode, different center frequencies are used for uplink and downlink, and data frames have no uplink and downlink distinctions in the time domain.

[90] FIG. 2 shows a schematic diagram of an 802.16 frame structure in the TDD mode. As shown in Figure 2, a TDD 802.16 data frame consists of a downlink subframe (DL-SubFrame), a TTG (Transmit/Receive Transition Gap), an uplink subframe (UL-SubFrame), and an RTG ( Receive/transmit Transition Gap, Receive/Transmit Conversion Interval). The TTG is used by the transceiver of the base station to switch from the transmit mode to the receive mode, and the RTG is used by the transceiver of the base station to switch from the receive mode to the transmit mode. In the example of FIG. 2, the uplink subframe and the downlink subframe occupy 4 subframes (24 OFDMA symbols), respectively, and the following describes the components of the downlink subframe and the uplink subframe, respectively.

[91] As shown in FIG. 2, the downlink subframe is composed of a preamble (Preamble), a frame control header (FCH, a Frame Control Header), a downlink subframe channel allocation message (DL-MAP), and multiple downlink burst data (Data). Burst) composition. The Preamble is used for the terminal to synchronize with the base station. The FCH is mainly used to describe the coding mode of the downlink subframe channel allocation message (DL-MAP). The DL-MAP is used to describe the composition of the downlink subframe. The modulation coding method of DL-MAP is specified by FCH.

The DL-MAP is composed of a plurality of information elements (DL-MAP-IEs), each of which corresponds to a downlink data block for describing the location of the data block in the current frame and the modulation and coding method used. Index DIUC (Downlink Interval Usage Code).

[92] The first downlink data block includes an uplink subframe channel allocation message (UL-MAP), and may also include a downlink channel description message (DCD, Downlink Channel Descriptor) and an uplink signal. - - Channel Description Message (UCD, Uplink Channel Descriptor) ₀ Each of the remaining downlink data blocks is data that is sent to different terminals, and generally one downlink data block corresponds to one receiving terminal.

The UL-MAP is composed of a plurality of information units and is used to describe the configuration of the uplink subframe. Each uplink information unit corresponds to a random access area (Region) or an uplink data block, and is used to describe the location of the area or data block in the next frame and the modulation and coding mode index UIUC (Uplink Interval Usage Code) used. . Downlink Subframe Channel Assignment Message DL-MAP, Uplink Subframe Channel Assignment Messages UL-MAP, DCD, and UCD are transmitted on the broadcast control channel, and each terminal can receive it.

[93] The DL-MAP-IE and the corresponding data area are indicated by the dashed arrows in Figure 2. For example, the data format of the first data area DL-Burst-1 of the downlink subframe is specified by DL-MAP-IE 1, and the data format of the first data area Burst-1 of the uplink subframe is UL-MAP- Specified by IE 1.

As shown in FIG. 2, the uplink subframe includes a Ranging subchannel region, a control signaling feedback portion, and an uplink data region for the bearer terminal to transmit to the base station. The uplink ranging channel is mainly used by the mobile station to perform closed-loop time, frequency and power adjustment, and bandwidth application. The control signaling feedback part includes a response channel (ACKCH) and a fast feedback channel (CQICH), and the response channel (ACKCH) is mainly used for information that the mobile station responds to the HARQ of the downlink channel correctly received, and the fast feedback channel (CQICH) includes mobile terminal feedback. Channel status information. The data area places the uplink data in accordance with the indication of the UL-MAP and UCD information in the downlink subframe.

Further, it should be noted that the present embodiment can be applied to a single antenna communication system, and can also be applied to a MIMO-OFDM system or a multi-antenna CDMA system. In addition, the present embodiment has been described above by taking a data frame of TDD as an example, but those skilled in the art should understand that this embodiment can also be applied to an FDD system. In FDD systems, signaling is sent out simultaneously with data through dedicated frequency bands.

Further, it should be noted that although the base station 600 in the OFDMA-based wireless communication system according to the present embodiment has been described above with reference to the schematic diagram shown in FIG. 6, those skilled in the art will understand that FIG. 6 The schematic diagrams shown are merely exemplary and are not intended to limit the scope of the invention, and those skilled in the art can modify or modify the schematic diagram shown in FIG. 6 according to actual needs.

[97] In addition, it should be noted that the resource allocation indicated in the control information such as MAP-IE is implemented in the medium access control (MAC) layer, and the corresponding data area is a logical data area, and the data Resource allocation at the physical layer requires a mapping from logical areas to data areas. There are two ways to do this mapping. One is continuous resource mapping, where symbols belonging to the same packet are allocated in an adjacent area. As shown in Figure 3-A, the data packet 301 is in an allocatable resource. - - The area occupies a contiguous block of data. If two data symbols are logically adjacent, their mapping is also adjacent in the physical resource area. The other is a decentralized resource mapping. The symbols that logically belong to the same data packet are distributed and mapped to the physical resource area, and the logical adjacent and physical neighboring of the data symbols are inconsistent. For example, as shown in Figure 3-B, the data packet is allocated to three non-contiguous resource regions. Those skilled in the art will appreciate that the present invention is primarily directed to the allocation of MAC layer logical resources, and does not involve mapping of logical resources and physical resources, as such mapping does not alter the results of data distribution and the capacity of the system.

[98] In addition, it should be noted that, in this embodiment, the resource area is given. However, those skilled in the art will appreciate that the invention is not limited thereto. In an actual system, the resource area to be allocated by the base station according to the present invention may be an available data area of the entire OFDMA downlink subframe or a part of the entire data area. Those skilled in the art can flexibly select these various embodiments in accordance with the needs of the actual application, which are all within the spirit and scope of the claimed invention.

[99] For example, as shown in Fig. 12, in Fig. 12 (A), all available data areas (packet resource allocation areas) 1201 are used for packet resource allocation. In Fig. 12(B), a portion 1202 of the available data area is used for packet resource allocation, and another part of the available data area (dynamic allocation resource area) 1203 uses a general dynamic resource allocation method.

[100] It should be understood by those skilled in the art that the service to which the embodiment is applied, the communication system used, the communication protocol, and the duplex communication mode can be flexibly selected and set according to the requirements of the specific application. All of the available resource areas or a portion of the available resource areas, etc., are all within the spirit and scope of the claims as claimed.

7 is a diagram showing a base station 700 in an OFDMA-based wireless communication system according to a second embodiment of the present invention.

As shown in FIG. 2, the base station 700 in the OFDMA-based wireless communication system according to the second embodiment of the present invention includes a packet unit 701, a resource allocation unit 702, and a control information generating unit 703.

[103] The grouping unit 701 is for grouping packets to be transmitted.

[104] As described above, the length of the control information can be reduced by the packet resource allocation method. Therefore, in the present embodiment, the packet to be transmitted is grouped by the grouping unit 701 and then resource allocation is performed, so that the length of the control information can be further reduced.

[105] In one example, the grouping unit 701 is configured to divide packets in a data packet to be transmitted that are to be modulated using the same modulation scheme into the same group. - -

[106] Since the data packets modulated by the same modulation scheme are divided into the same group, it is only necessary to include information indicating the modulation scheme shared by the intra-group data packets in the control information for the group. The length of the control information can be reduced.

In another example, the grouping unit 701 is configured to divide the packets of the data packets to be transmitted that are the same size after being modulated according to the modulation mode to be used into the same group.

[108] Since the data packets whose sizes will be the same after being modulated are divided into the same group, it is only necessary to include information indicating the packet size shared by the intra-group packet in the control information for the group. Thus, the length of the control information can be reduced.

It should be understood by those skilled in the art that the implementation manner of the grouping unit 701 of the present embodiment is not limited to the above example, but a specific grouping manner may be flexibly selected according to the requirements of the actual application, which should all be in the present invention. Within the spirit and scope of the protection requested.

[110] The resource allocation unit 702 is configured to allocate the allocatable resources in units of OFDMA symbols to the data packets to be transmitted.

As described above, the resource allocation method of the prior art allocates resources in units of resource blocks (RBs), and the resource allocation unit 601 of the present embodiment allocates resources in units of OFDMA symbols. Since the packet length is an integer multiple of the OFDMA symbol, allocating resources in units of OFDMA symbols can prevent fragmentation of resource regions due to the packet length being not an integer multiple of the resource block length.

For example, when the present embodiment is applied to a VoIP service, the capacity of the VoIP service can be improved by reducing the fragmentation of the resource area generated in the resource allocation process.

Further, in the present embodiment, the resource allocation unit 702 can perform resource allocation in units of OFDMA symbols only in each group, and resource allocation in units of resource blocks (RBs) between groups. When the base station of the present embodiment is applied to a communication system that specifies resource allocation in units of resource blocks, such a resource allocation manner can be used to prevent fragmentation of resource regions in the group. Of course, resources may still exist between groups. Area fragmentation.

[115] When the base station of the present embodiment is applied to a communication system that does not specify resource allocation in units of resource blocks, the resource allocation unit 702 can perform the intra-group and inter-group in units of OFDMA symbols. Resource allocation, so that the generation of resource regions within and between groups can be sufficiently prevented. - -

The above-described resource allocation manner of the resource allocation unit 702 will be specifically described below by two examples.

[117] In one example, the resource allocation unit 702 is configured to continuously allocate the allocatable resources to each group divided by the grouping unit 701 in units of resource block sizes specified in the wireless communication system, and The resources allocated to each group are continuously allocated to the packets in the group in units of OFDMA symbols. That is to say, in this example, resource allocation is performed only in units of OFDMA symbols within a group, and resource allocation is still performed in units of resource blocks between groups.

[118] For example, as shown in FIG. 8, the available resource area 801 in FIG. 8 is allocated to four groups, which are divided according to a modulation method, and the data packet in the group 1 uses a modulation mode MCS1, a group. The data packet in 2 uses modulation mode MCS2, the data packet in group 3 uses modulation mode MCS3, and the data packet in group 4 uses modulation mode MCS4. The first set of 802 packets are allocated three consecutive areas of 803, 804, and 805, occupying a total of 10 resource blocks (RBs). Compared with the allocation method of FIG. 5, it can be seen that since resource allocation is performed in units of OFDMA symbols, there is no resource region fragment between resource regions of different data packets allocated to the first group 802, and thus FIG. 5 A total of 2 RB resources are saved compared to the resource areas allocated to the first group 802.

In addition, as shown in FIG. 8, the last RB to which the last packet of the first group 802 is allocated is RB10, and the second group of allocated RBs starts from RB 11, and still exists between RB10 and RB11. Resource area fragmentation. This is because in this example, resource allocation is performed only in units of OFDMA symbols within a group, and resource allocation is still performed in units of RBs between groups, so there may still be resource area fragments between groups.

[120] In another example, the resource allocation unit 702 is configured to continuously allocate the allocatable resources in units of OFDMA symbols to each of the packets in each group divided by the grouping unit. That is to say, in this example, resource allocation is performed in units of OFDMA symbols, whether between groups or within groups.

[121] For example, as shown in FIG. 9, the available resource area 901 in FIG. 9 is allocated to four groups, which are divided according to a modulation method, and the data packet in the group 1 uses a modulation method MCS1, a group. The data packet in 2 uses modulation mode MCS2, the data packet in group 3 uses modulation mode MCS3, and the data packet in group 4 uses modulation mode MCS4. The data packets of the first group 902 are allocated three consecutive areas 903, 904 and 905, occupying a part of RB1 to RB10. Compared with the allocation method of FIG. 5, it can be seen that since resource allocation is performed in units of OFDMA symbols, there is no resource region fragment between resource regions of different data packets allocated to the first group 902, and thus FIG. 5 A total of 2 RB resources are saved compared to the resource areas allocated to the first group 902. - -

Furthermore, as shown in FIG. 9, the last RB to which the last packet of the first group 902 is allocated is part of RB10, and the second group of assigned RBs is then assigned to the last one of the first group. The data is allocated at the end of the resource area of the data packet (i.e., the second half of RB10 in Fig. 9), and therefore, the resource area fragment is no longer present between the resource areas of the data packets allocated to the first group and the second group. . This is because in this example, resource allocation is also performed in units of OFDMA symbols between groups, so there is no resource area fragment between groups.

The control information generating unit 703 is configured to generate control information indicating the resource allocated to the data packet by the resource allocating unit 702.

It should be understood by those skilled in the art that the known control information format and the like used by the control information generating unit 703 when generating the control information can be flexibly selected according to the requirements of the actual application, which should be claimed in the present invention. Within the spirit and scope. For example, the control information may include a start address of a resource allocated to the data packet by the resource allocation unit 702, a modulation scheme corresponding to the data packet, and the like.

[125] Optionally, in this embodiment, the control information may include information indicating a starting location of the resource allocated by the resource allocating unit 702 for each group divided by the grouping unit 701, indicating each group Information on the number of packets included in the packet, and modulation method information.

[126] For example, in the second example described above, the control information generating unit may generate a corresponding DL-MAP-IE message as control information, the format of which is, for example, as shown in Table 3:

[127] Table 3 Contents of DL-MAP-IE Representation Size (number of bits) Meaning

MAP- IE type 4 type: open/closed, single/multi-antenna, continuous/non-continuous allocation

Resource Offset 8 start position

CID 16 data type broadcast

Number of 8 Number of packets in the group

Al locat ions

User Bi tmap 5 terminal specified format

The size of the terminal packet in the Resource 4 group

Al locat ion

Bi tmap - -

[128] The format of Table 3 is in units of groups, so that there is no need to allocate a MAP-IE control header for each data packet, thereby reducing the length of the control information and saving the resources of the downlink subframe. The difference between the MAP-IE corresponding to the resource allocation mode of FIG. 8 and FIG. 9 is that the number of bytes required for the starting position of the resource area is different, because the manner of FIG. 9 is more precise, so more bytes are needed to represent .

[129] It should also be noted that the number of bytes in Table 3 can be changed according to different protocols and system parameters. For example, if there are 16 MCS types, the MCS index occupies 4 bytes; if there are 31 MCS , the MCS index occupies 5 bytes.

Furthermore, if the resource allocation method used by the resource allocation unit 702 is more complicated or contains more options, the corresponding fields in the control information generated by the control information generating unit 703 are also more complicated. It should be understood by those skilled in the art that the format of the control information generated by the control information generating unit can be flexibly adjusted according to the needs of the actual application, and all of them should be within the spirit and scope of the claimed invention.

For example, FIG. 14 shows a schematic diagram of an example of content of control information according to an embodiment of the present invention. Packets are categorized by the number of RBs occupied by the data packet. Packets occupying the same or a similar number of RBs and similar modulation and coding schemes (MCS) are allocated to the same group. As shown in Figure 14, the control information (i.e., the user bitmap information in Figure 14) includes:

[132] (1) User information, indicating which users the data packet is assigned to. In FIGS. 14(a) to 14(c), a bit of 1 in the first row indicates that the user corresponding to the bit is assigned data, and a value of 0 indicates that the user corresponding to the bit is not allocated data this time;

[133] (2) Resource allocation information, indicating the number of packets and modulation and coding information corresponding to each user. 14(a) shows the number of packets and modulation and coding information of different users in a unified format, and FIG. 14(b) and FIG. 14(c) respectively show the number of packets and modulation and coding modes of the user. The advantages of the representations of Figures 14(b) and 14(c) are that it is convenient to indicate that a user is assigned multiple packets, and the representation of Figure 14(a) applies to users within the same group. A case where only one modulation coding method is used. - -

Further, another embodiment of the resource allocation unit 702 will be specifically described below in conjunction with yet another example of the resource allocation unit 702.

[135] In the present example, in the case where the packet to be transmitted by the packet unit 701 is to be divided into the same group after the packets which are modulated in the same manner according to the modulation scheme to be used, the modulation used The modulation scheme with the lowest code rate in the mode is determined as a modulation scheme to be used for each data packet in the group, and the assignable resources are continuously allocated to the packet unit in units of resource block sizes specified in the wireless communication system. Each group divided by 701, and resources allocated to each group are continuously allocated to the packets in the group in units of OFDMA symbols.

That is to say, in the present example, the resource allocation unit 702 performs resource allocation only in units of OFDMA symbols within the group, and resource allocation is still performed in units of resource blocks between groups. However, unlike the above example, in this example, the packet unit divides the packets whose size will be the same after the modulation into the same group, and the resource allocation unit 702 will request the packets in each group. The modulation scheme with the lowest code rate among the modulation schemes used is determined as the modulation scheme used for each packet in the group. In this way, the resource segment allocated by the modulation scheme with the highest code rate has the most redundant fragments, and the modulation scheme with low code rate has higher reliability. Therefore, this example uses the lowest code rate by uniformly using the data packets in the group. The modulation method further reduces the fragmentation of the resource area on the one hand, and improves the reliability of the data on the other hand.

[137] The following example is given by two practical examples.

[138] For example, the VoIP service has a packet size of 44 bytes and 18 bytes (352/144 bits), and one RB includes 96 modulation symbols. The modulation code set (MCS) in Table 4 uses 802.16m-09/868r2 and AWD documents, a total of 16 kinds, which are represented by 0-15 respectively, which are occupied by VoIP silent data packets and activation data packets of different MCSs. The number of RBs is shown in the fifth column of Table 4.

[139] Table 4 VoIP data resource allocation example table corresponding to 802.16m modulation and coding format

MCS index modulation mode rate RB number grouping

(44 bytes / 18 bytes)

0 0000 QPSK 31/256 16/7 1

1 0001 QPSK 48/256 10/4 1

2 0010 QPSK 71/256 7/3 2

3 0011 QPSK 101/256 5/2 2 - -

[140] As can be seen from Table 4, the grouping results are shown in the sixth column of Table 4 and are divided into four groups. Up to 4 modulation and coding schemes (MCS) per group, as shown in column 2 of Table 4. The four MCSs of the first group are represented by {00, 01, 10, 11}, and the corresponding number of RBs is {16, 10, 7, 4}, and the number of RBs corresponding to the four MCSs of the second group is { 7, 5, 3, 2}. The third group uses only three types of MCS. Since QPSK-135/256 and 171/256 occupy the same number of resource blocks, the former coding method is uniformly used. Similarly, the fourth group of silent data packets are also uniformly used in the 16QAM-102/256 mode, and the active data packets are used in three modulation and coding modes: 16QAM-102/256, 16QAM-128/256, and 64QAM-157/256.

[141] The above packet saves the signaling overhead of the MCS (i.e., reduces the length of the control information) because only two bits in the group are required to represent the MCS, and a total of four groups can be represented by only two bits. If the MCS and resource allocation indications are respectively performed, each packet requires 5 bits to represent MCS (32 packet lengths). At the same time, the above example uses the same MCS with the lowest code rate in the group to further reduce the resource region fragmentation and improve the reliability of the data.

[142] For another example, as shown in Table 5, the modulation and coding set (MCS) uses the 802.16e standard, and a total of 11 modulation and coding modes, and the number of resource blocks occupied by the corresponding VoIP activation data packet/silent data packet is shown in Table 5. The fourth column is shown. - -

[143] Table 5 802.16e modulation coding method and corresponding packet resource allocation example table

[144] The comparison between the above example and the complexity of the control information for not using the packet resource allocation is as follows: the data packet alone indicating the packet does not require 5 bits of control information (4-bit MCS indication and 1-bit activation/ Silent packet indication). The use of packet resource allocation requires only 4 bits of control information (2-bit MCS indication and 2-bit packet indication).

Another embodiment of the resource allocation unit 702 is described in detail below in conjunction with yet another example of the resource allocation unit 702.

[146] This example can further reduce the overhead of control information. As shown in FIG. 10, the base station sorts the data packets scheduled in the current frame according to their modulation and coding modes (packet size), and then performs resource allocation according to a certain order, for example, according to the code rate.

[147] A specific example of using the IEEE802.16e modulation code set is: BPSK-1/6 BPSK-1/4 BPSK-1/2 QPSK-1/2 QPSK-3/4 16QAM-1/2 ^ 16QAM- 3/4 ^ 64QAM-1/2 ^ 64QAM-2/3 ^ 64QAM-3/4 ^ 64QAM-5/6 ₀ Packets are placed in the resource area in this order. - -

[148] Since the source data of a VoIP packet has only two length formats (44 bytes and 18 bytes), there are two packet lengths corresponding to each modulation and encoding format. Packets of the same size are allocated in a continuous interval. If the order of the MCS is determined in advance, the control information only needs to indicate the number of packets modulated by using different MCSs. The starting position of each packet in the group is in advance. The determined rules can be calculated.

[149] For example, if the first group is a QPSK-1/2 encoded active state packet (352 symbols) and there are 3 packets, the starting position of the second group is 352*3=1056.

[150] Further, for a given resource area, data can be allocated from the middle to the middle, so that at least two sets of data (the first group and the last group) do not need to be specified. At this time, two pointers are needed to represent the spare resource intervals, which are respectively represented by index 1 and index 2 in Fig. 10, and when the index 1>=index 2, the resource allocation ends. At this time, the order of each group needs to be determined in advance as in Fig. 8.

[151] The corresponding packet control information (MAP) can be used in the same format as the group resource allocation, except that the starting position of each group will be different. This is equivalent to changing the value of the MAP-IE Type in Table 3. At this time, the number of bits occupied by the group's starting position (Resource Offset) is much reduced, because the starting position of each group can be calculated by a predetermined format calculation.

[152] Another advantage of the embodiment of FIG. 10 is: when there is a data reception error that needs to be retransmitted, since the user channel quality of the high-order modulation coding mode (MCS) is good, the retransmission probability is small, and the lowest order The MCS has a large probability of data retransmission, so this is advantageous for operations such as successfully receiving data packets and retransmitting erroneous data packets. At this time, the data packets of the highest-order MCS and the lowest-order MCS will get the same processing result due to the similar signal-to-noise ratio, which is beneficial to the batch processing of the data in the group.

As can be seen from the above, the base station 700 in the OFDMA-based wireless communication system according to the second embodiment of the present invention allocates the allocatable resources in units of OFDMA symbols to each other by grouping the data packets to be transmitted. The data packets to be transmitted in each group are allocated resources in units of resource blocks (RBs) in the prior art, and thus it is possible to prevent the length of the data packet from being an integer multiple of the resource block length in the resource allocation process. The resource region fragmentation is caused, so that the resource region fragmentation generated in the resource allocation process on the base station 700 side in the OFDMA-based wireless communication system can be reduced, and the control information can be further reduced due to resource allocation based on the packet grouping manner. The length, saving signaling overhead.

[154] In addition, it should be noted that although the above diagram is combined with the schematic diagram shown in FIG. The base station 700 in the OFDMA-based wireless communication system of the example is described, but those skilled in the art should understand that the schematic diagram shown in FIG. 7 is merely exemplary, and is not intended to limit the scope of the present invention. The personnel can completely modify or modify the schematic diagram shown in FIG. 7 according to actual needs.

[155] In addition, it should be noted that the continuous allocation of data packets in the embodiment may refer to continuous in the time domain, or may refer to continuous in the frequency domain, or may also refer to time-frequency. For the continuation, for example, see Figure 13 (a), Figure 13 (b), and Figure 13 (c), respectively, where the different labels of the shaded packets represent different placement orders. All of the embodiments of the present invention are applicable to the above three consecutive allocation scenarios. It will be understood by those skilled in the art that the continuation of the continuation of the continuation of the singularity of the singularity of the present invention is within the spirit and scope of the invention as claimed.

[156] Furthermore, it should be noted that the present embodiment is mainly directed to the allocation of logical resources of the MAC layer, and does not involve the mapping problem of logical resources and physical resources, because the mapping does not change the result of the data distribution and the system. capacity.

In addition, it should also be noted that in the present embodiment, the resource area is given. However, those skilled in the art will appreciate that the invention is not limited thereto. In an actual system, the resource area to be allocated by the base station according to the present invention may be an available data area of the entire OFDMA downlink subframe or a part of the entire data area. Those skilled in the art can flexibly select these various embodiments in accordance with the needs of the actual application, which are all within the spirit and scope of the claimed invention.

[158] For example, as shown in Fig. 12, in Fig. 12 (A), all of the available data areas (packet resource allocation areas) 1201 are used for packet resource allocation. In Fig. 12(B), a portion 1202 of the available data area is used for packet resource allocation, and another part of the available data area (dynamic allocation resource area) 1203 uses a general dynamic resource allocation method.

[159] Optionally, in this embodiment, the data packet to be transmitted includes a data packet to be retransmitted. For example, for the processing of HARQ packets that need to be retransmitted, the retransmission indicator variable HARQ ReTx in Table 3 may indicate whether the current group is a new packet or a retransmission packet and the number of retransmissions of the retransmission packet.

[160] Since, in general, each frame of data resource allocation, the HARQ data that needs to be retransmitted has the highest priority, and will be scheduled in preference to other data packets, so another implementation manner of this embodiment is to retransmit. Packets and new packets are grouped together in different groups, not just MCS.

[161] A typical data distribution example using the above embodiment is shown in FIG. In Figure 11 - - In, 1101 and 1102 are both HARQ packets, and different packets contain different MCS format packets. The next step is the new packet. It is also possible to group according to the number of HARQ retransmissions, but this has little effect on reducing the length of the control information.

[162] Alternatively, in the embodiment, the wireless communication system may be based on the IEEE 802.16 protocol and the time division duplex communication mode, and the control information may be included in a downlink frame channel assignment message in the downlink frame.

[163] Alternatively, optionally, in the embodiment, the wireless communication system may be based on an IEEE 802.16 protocol and a frequency division duplex communication mode, and the control information may be included in a signaling message transmitted using a dedicated frequency band.

[164] Alternatively, in the present embodiment, the wireless communication system may organize a Long Term Evolution Communication (3GPP LTE) standard based on a third generation partnership plan.

[165] It should be understood by those skilled in the art that the service to which the present embodiment is applied, the communication system used, the communication protocol, and the duplex communication mode can be flexibly selected and set according to the requirements of the specific application. Is the total available resource area or a part of the available resource area, the above-described grouping method used by the grouping unit 701, the resource allocation method used by the resource allocating unit 702, and the control information format used by the control information generating unit 703 And so on, it should be within the spirit and scope of the claims as claimed.

According to an embodiment of the present invention, a resource allocation method used in a base station in an OFDMA-based wireless communication system is also provided.

15 shows a flow chart of a resource allocation method used in a base station in an OFDMA-based wireless communication system according to Embodiment 3 of the present invention.

As shown in FIG. 15, a resource allocation method used in a base station in an OFDMA-based wireless communication system according to Embodiment 3 of the present invention starts from step S1501.

[169] In step S1501, the allocatable resources are allocated in units of OFDMA symbols to the data packets to be transmitted. In step S1502, control information indicating a resource assigned to the packet is generated.

As described above, the resource allocation method of the prior art allocates resources in units of resource blocks (RBs), and in this embodiment, resources are allocated in units of OFDMA symbols. Since the packet length is an integer multiple of the OFDMA symbol, allocating resources in units of resource blocks (RBs) can prevent resource region fragmentation due to the packet length being not an integer multiple of the resource block length. - -

[171] For example, when the present embodiment is applied to a VoIP service, the capacity of the VoIP service can be improved because the resource area fragmentation generated in the resource allocation process is reduced.

It should be understood by those skilled in the art that the present embodiment is not limited to the VoIP service. As long as the service has a fixed data packet length, the resource allocation method provided by this embodiment can be used for resource allocation.

Then, in step S1502, a control station indicating the resource assigned to the data packet is generated.

[174] It should be understood by those skilled in the art that the known control information format and the like used in generating the control information in this embodiment can be flexibly selected according to the requirements of the actual application, and all of them should be claimed in the present invention. Within the spirit and scope. Therefore, for the sake of brevity of the description, the specific control information format used in generating the control information in the present embodiment will not be described in detail herein.

As apparent from the above, the resource allocation method used in the base station in the OFDMA-based wireless communication system according to the third embodiment of the present invention allocates the assignable resources to the data packets to be transmitted in units of OFDMA symbols, It is not in the prior art that resources are allocated in units of resource blocks (RBs), so that it is possible to prevent resource region fragmentation due to the length of the data packet not being an integer multiple of the resource block length in the resource allocation process, thereby being able to reduce the OFDMA-based A resource region fragment generated in a resource allocation process on the base station side in a wireless communication system.

[176] Optionally, in this embodiment, the data packet to be transmitted may include a data packet to be retransmitted.

[177] Optionally, in this embodiment, the wireless communication system may be based on an IEEE 802.16 protocol and a time division duplex communication mode, and the control information may be included in a downlink frame channel assignment message in a downlink frame.

[178] Alternatively, optionally, in the embodiment, the wireless communication system may be based on an IEEE 802.16 protocol and a frequency division duplex communication mode, and the control information may be included in a signaling message transmitted using a dedicated frequency band.

[179] Alternatively, in the present embodiment, the wireless communication system may organize a long term evolution communication standard based on a third generation partnership plan.

In addition, it should be noted that although the resource allocation method used in the base station in the OFDMA-based wireless communication system according to the present embodiment has been described above with reference to the flowchart shown in FIG. 15, the technology in the art It should be understood that the flowchart shown in FIG. 15 is merely exemplary, and is not intended to limit the scope of the present invention, and those skilled in the art can modify or modify the flowchart shown in FIG. 15 according to actual needs. - -

[181] Furthermore, it should be noted that the present embodiment is mainly directed to the allocation of logical resources of the MAC layer, and does not involve the mapping problem of logical resources and physical resources, because the mapping does not change the result of the data distribution and the system. capacity.

[183] It should be understood by those skilled in the art that the service to which the present embodiment is applied, the communication system used, the communication protocol, and the duplex communication mode can be flexibly selected and set according to the requirements of the specific application. All of the available resource areas or a portion of the available resource areas, etc., are all within the spirit and scope of the claims as claimed.

As shown in FIG. 16, a resource allocation method used in a base station in an OFDMA-based wireless communication system according to Embodiment 4 of the present invention starts from step S1601.

[186] In step S1601, packets to be transmitted are grouped. The length of the control information can be further reduced by grouping the data packets to be transmitted and then performing resource allocation.

In one example, step S1601 includes dividing packets of the data packets to be transmitted that are to be modulated using the same modulation scheme into the same group.

[188] Since the data packets modulated by using the same modulation scheme are divided into the same group, it is only necessary to include information indicating the modulation scheme shared by the intra-group packet in the control information for the group. The length of the control information can be reduced.

In another example, step S1601 includes dividing, among the data packets to be transmitted, packets of the same size after being modulated according to the modulation scheme to be used into the same group.

[190] Since the data packets whose sizes will be the same after being modulated are divided into the same group, it is only necessary to include information indicating the packet size shared by the intra-group packet in the control information for the group. Thus, the length of the control information can be reduced.

It should be understood by those skilled in the art that the grouping manner used in step S1601 in this embodiment is not limited to the above example, but the specific points can be flexibly selected according to the requirements of the actual application. - The group embodiments are all within the spirit and scope of the claimed invention.

[192] Then, in step S1602, the allocatable resources are allocated in units of OFDMA symbols to the data packets to be transmitted.

As described above, the resource allocation method of the prior art allocates resources in units of resource blocks (RBs), and the present embodiment allocates resources in units of OFDMA symbols. Since the packet length is an integer multiple of the OFDMA symbol, it is possible to prevent the occurrence of resource region fragmentation because the packet length is not an integer multiple of the resource block length.

[194] For example, when the present embodiment is applied to a VoIP service, the capacity of the VoIP service can be improved because the resource area fragmentation generated in the resource allocation process is reduced.

In an example, step S1602 includes: continuously assigning the allocatable resources to each of the divided groups in units of OFDMA symbols. That is to say, resource allocation is performed in units of OFDMA symbols within and between groups, so that generation of resource region fragments within and between groups can be sufficiently prevented.

[197] In another example, step S1602 includes: continuously assigning the assignable resources to each of the divided groups in units of resource block sizes specified in the wireless communication system, and is to be allocated to each The resources of the group are continuously allocated to the data packets in the group in units of OFDMA symbols. That is to say, resource allocation is performed in units of OFDMA symbols only in each group, and resource allocation is still performed in units of resource blocks (RBs) between groups. When the resource allocation method of the present embodiment is applied to a communication system that specifies resource allocation in units of resource blocks, the resource allocation method can be used to prevent fragmentation of resource regions within the group, although it is still possible between groups. There is a fragment of the resource area.

[198] In still another example, in step S1601, in a case where the data packets to be transmitted are divided into the same group in the data packets to be the same after being modulated according to the modulation mode to be used, step S1602 includes : determining the modulation scheme with the lowest code rate in the modulation mode to be used in each group of the divided packets as the modulation mode to be used for each data packet in the group, and assigning the assignable resources to the The resource block size specified in the wireless communication system is continuously allocated to each of the divided groups in units, and the resources allocated to each group are continuously allocated to the data packets in the group in units of OFDMA symbols.

[199] That is to say, in this example, in step S1602, only the OFDMA character is used within the group. - - The number is allocated for the unit, and the resource allocation is still performed in units of resource blocks between the groups. However, unlike the above example, in the present example, the data packets whose sizes will be the same after being modulated are divided into the same group in step S1601, and the data in each group is set in step S1602. The modulation scheme with the lowest code rate in the modulation scheme to be used by the packet is determined as the modulation scheme used for each packet in the group. In this way, the resource segment allocated by the modulation scheme with the highest code rate has the most redundant fragments, and the modulation scheme with low code rate has higher reliability. Therefore, this example uses the lowest code rate by uniformly using the data packets in the group. The modulation method further reduces the fragmentation of the resource area on the one hand, and improves the reliability of the data on the other hand.

[200] Then, in step S1603, a control station indicating the resource assigned to the data packet is generated.

[201] Optionally, in this embodiment, the control information may include information indicating a starting location of resources allocated for each group divided, indicating the number of data packets included in each group. Information, and modulation method information.

It should be understood by those skilled in the art that the known control information format and the like used by the control information generating unit 703 when generating the control information can be flexibly selected according to the requirements of the actual application, which should be claimed in the present invention. Within the spirit and scope.

[203] Optionally, in this embodiment, the data packet to be transmitted may include a data packet to be retransmitted.

Optionally, in this embodiment, the wireless communication system may be based on an IEEE 802.16 protocol and a time division duplex communication mode, and the control information may be included in a downlink frame channel assignment message in a downlink frame.

Alternatively, in the present embodiment, the wireless communication system may be based on an IEEE 802.16 protocol and a frequency division duplex communication mode, and the control information may be included in a signaling message transmitted using a dedicated frequency band.

[206] Alternatively, optionally, in the present embodiment, the wireless communication system may organize a long term evolution communication standard based on a third generation partnership plan.

[207] From the foregoing, it is known that the basis of the OFDMA-based wireless communication system according to Embodiment 4 of the present invention allocates the assignable units of the OFDMA symbols to the packets to be transmitted in each group instead of the existing ones. In the technology, resources are allocated in units of resource blocks (RBs), and resource region fragments are caused by multiple times, so that resource region fragments generated in the resource allocation process on the base station side in the OFDMA-based wireless communication system can be reduced, and at the same time Due to packet based - - Packet allocation for resource allocation can further reduce the length of control information and save signaling overhead.

Further, it should be noted that although the resource allocation method used in the base station in the OFDMA-based wireless communication system according to the present embodiment has been described above with reference to the flowchart shown in FIG. 16, the technology in the art It should be understood that the flowchart shown in FIG. 16 is merely exemplary, and is not intended to limit the scope of the present invention. Those skilled in the art can modify or modify the flowchart shown in FIG. 16 according to actual needs.

[209] In addition, it should be noted that the continuous allocation of data packets in the embodiment may refer to continuous time domain, continuous frequency domain, or time frequency. For the continuation, for example, see Figure 13 (a), Figure 13 (b), and Figure 13 (c), respectively, where the different labels of the shaded packets represent different placement orders. All of the embodiments of the present invention are applicable to the above three consecutive allocation scenarios. It will be understood by those skilled in the art that the continuation of the continuation of the continuation of the singularity of the singularity of the present invention is within the spirit and scope of the invention as claimed.

[210] Furthermore, it should be noted that the present embodiment is mainly directed to the allocation of logical resources of the MAC layer, and does not involve the mapping problem of logical resources and physical resources, because the mapping does not change the result of the data distribution and the system. capacity.

[212] It should be understood by those skilled in the art that the service to which the present embodiment is applied, the communication system used, the communication protocol, and the duplex communication mode can be flexibly selected and set according to the requirements of the specific application. Is the total available resource area or a part of the available resource area, the above-described grouping method used in step S1601, the above-mentioned resource allocation method used in step S1602, and the control information format used in step S1603. And so on, it should be within the spirit and scope of the claims as claimed.

The specific implementation of the steps in the third embodiment to the fourth embodiment of the present invention may refer to the configuration of the base station in the OFDMA-based wireless communication system according to the first embodiment to the second embodiment of the present invention described above. And the function of each component. For the simplicity of the instructions - - See, the specific implementation of each of the above steps is not described in detail here.

Further, it should be noted that although the resource allocation method used in the base station in the OFDMA-based wireless communication system according to the present embodiment has been described above with reference to the flowcharts shown in FIGS. 15-16, It should be understood by those skilled in the art that the flowcharts shown in FIGS. 15-16 are merely exemplary, and are not intended to limit the scope of the present invention. Those skilled in the art can fully perform the flowcharts shown in FIG. 15-16 according to actual needs. Variant or modified.

It is also noted that the steps of performing the series of processing in the flowcharts shown in the above-mentioned Figs. 15-16 can be naturally performed in chronological order in the order illustrated, but need not necessarily be performed in chronological order. Certain steps may be performed in parallel or independently of one another.

While the invention and its advantages have been described in detail, it is understood that various modifications, alternatives and variations may be made without departing from the spirit and scope of the invention as defined by the appended claims.

[217] Finally, it should also be noted that, in this context, relational terms such as first and second are used merely to distinguish one entity or operation from another entity or operation, without necessarily requiring or Imply that there is any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "comprising," or "includes" are intended to include a non-exclusive inclusion, such that a process, method, article, or device that includes a plurality of elements includes not only those elements but also Other elements, or elements that are inherent to such a process, method, item, or device. Without further restrictions, the statement "includes a ..." defined element, and It is not excluded that there are additional identical elements in the process, method, article or device that comprises the described elements.

The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. Various modifications and changes may be made to the above-described embodiments without departing from the spirit and scope of the invention. Therefore, the scope of the invention is to be limited only by the appended claims and their equivalents.

Claims

Claim

1. A base station in an OFDMA-based wireless communication system, comprising:

a resource allocation unit, configured to allocate an allocatable resource to the data packet to be transmitted in units of OFDMA symbols;

And a control information generating unit configured to generate control information indicating a resource allocated to the data packet by the resource allocation unit.

2. The base station according to claim 1, further comprising:

a grouping unit, configured to group the data packets to be transmitted.

3. The base station according to claim 2, wherein the grouping unit is configured to:

The packet to be transmitted

Packages are grouped into the same group; or

The packet to be transmitted

The same packets are divided into the same group.

4. The base station according to claim 2, wherein the resource allocation unit is configured to: continuously allocate an allocatable resource in units of OFDMA symbols to each of each group divided by the grouping unit Data packet; or

The allocateable resources are continuously allocated to each group divided by the grouping unit in units of resource block sizes specified in the wireless communication system, and resources to be allocated to each group are represented by OFDMA symbols Units are continuously assigned to packets in the group.

5. The base station according to claim 2, wherein: the data packets of the same size after modulation are divided into the same group; and the modulation mode of the lowest code rate in the modulation mode of the packet is determined. For the modulation scheme to be used for each data packet in the group, the assignable resources are continuously allocated to each group divided by the grouping unit in units of resource block sizes specified in the wireless communication system And the resources allocated to each group are continuously allocated to the packets in the group in units of OFDMA symbols.

6. The base station according to claim 2, wherein the control information comprises indicating the resource Information of the position, information indicating the number of packets included in each group, and modulation mode information.

7. The base station of claim 1, wherein the data packet to be transmitted comprises a data packet to be retransmitted.

8. The base station according to claim 1, wherein:

The wireless communication system is based on an IEEE 802.16 protocol and a time division duplex communication mode, and the control information is included in a downlink frame channel allocation message in a downlink frame; or

The wireless communication system is based on an IEEE 802.16 protocol and a frequency division duplex communication method, and the control information is included in a signaling message transmitted using a dedicated frequency band; or

The wireless communication system organizes long term evolution communication standards based on the 3rd Generation Partnership Project.

9. A resource allocation method for use in a base station in an OFDMA-based wireless communication system, comprising:

Allocable resources are allocated to the data packet to be transmitted in units of OFDMA symbols; and

Control information is generated indicating resources allocated to the data packet.

10. The resource allocation method according to claim 9, further comprising: grouping the data packets to be transmitted.

11. The resource allocation method according to claim 10, wherein the grouping the data packets to be transmitted comprises:

The transmission to be transmitted

Packets are grouped into the same group; or the same packets are grouped into the same group.

12. The resource allocation method according to claim 10, wherein the allocating the allocatable resources in units of OFDMA symbols to the data packets to be transmitted comprises:

Allocable resources are continuously allocated in units of OFDMA symbols to each packet in each of the divided groups; or

The assignable resources are continuously allocated to each of the divided groups in units of resource block sizes specified in the wireless communication system, and resources to be allocated to each group are continuously allocated to the OFDMA symbols in units of OFDMA symbols The packets in this group.

13. The resource allocation method according to claim 10, wherein: the packets of the same size are modulated into the same group after being modulated according to the modulation mode to be used;

The modulation mode of allocating the allocatable resources to the data packets to be transmitted in units of OFDMA symbols is determined as a method to be used for each data packet in the group, and the available resources are used in the wireless communication The resource block size specified in the system is continuously allocated to each of the divided groups in units, and the resources allocated to each group are continuously allocated to the packets in the group in units of OFDMA symbols.

The resource allocation method according to claim 10, wherein the control information includes information indicating a start position of a resource allocated for each of the divided groups, indicating a data packet included in each of the groups Number of information, and modulation method information.

The resource allocation method according to claim 9, wherein the data packet to be transmitted includes a data packet to be retransmitted.

16. The resource allocation method according to claim 9, wherein: