KR20100081758A - Apparatus and method for signaling for persistent allocation scheme in a broadband wireless communication system - Google Patents

Abstract

PURPOSE: A signaling apparatus for a persistent allocation scheme in a broadband wireless communication system, and a method thereof are provided to enable a terminal to identify an allocated fixing resource one by one without confusion by recognizing the fixing resource to the terminal when changing one fixing resource among plural fixing resources allocated to the same terminal. CONSTITUTION: At least one of an MCS(Modulation and Coding Scheme) level, position and size of a fixing resource allocated to a terminal is changed. An ACID(HARQ Channel ID) field map IE(Information Element) is set up as the same value as the ACID of the fixing resource. The map IE is transmitted to the terminal(321), and includes at least one filed which indicates the MCS level, position and size of the fixing resource.

Description

Signaling apparatus and method for fixed allocation in broadband wireless communication system {APPARATUS AND METHOD FOR SIGNALING FOR PERSISTENT ALLOCATION SCHEME IN A BROADBAND WIRELESS COMMUNICATION SYSTEM}

The present invention relates to a broadband wireless communication system, and more particularly, to a signaling apparatus and method for a fixed allocation scheme of radio resources in a broadband wireless communication system.

The 4th Generation (hereinafter referred to as '4G') communication system provides users with services of various quality of service (QoS) using a transmission rate of about 100 Mbps. There is active research going on. The representative communication system is the Institute of Electrical and Electronics Engineers (IEEE) 802.16 system. The IEEE 802.16 system orthogonal frequency division multiplexing (hereinafter referred to as 'OFDM') / Orthogonal Frequency Division Multiple Access (orthogonal frequency division multiplexing) to support a broadband transmission network on a physical channel (Physical Channel) Multiple Access, hereinafter referred to as " OFDMA "

In a broadband wireless communication system such as the IEEE 802.16 system, a base station allocates resources to respective terminals for transmitting and receiving a packet. The base station transmits a map (MAP) message indicating a resource allocation result such as the location and size of the allocated resource, a modulation scheme, a coding rate, and the like through the downlink channel. At this time, resource allocation is performed for resources within a predetermined section, and thus, a map Information Element (IE) is transmitted for each predetermined section. However, in the case of a service in which packets of the same size are transmitted periodically, such as a Voice over Internet Protocol (VoIP) service, transmitting map IEs having the same content every time a packet is transmitted increases the waste of resources. Therefore, in the case of a service having a certain transmission period, waste of resources due to map IEs can be reduced by applying a fixed allocation scheme of allocating resources in a fixed manner. According to the fixed allocation scheme, in case of downlink communication, the map IE and the packet are transmitted only at the first resource allocation, and after that, only the packet is transmitted without the map IE. Accordingly, the terminal using the fixed allocated resource continues to use the fixed allocated resource without the map IE until the allocation cancellation information or the allocation change information is received. Hereinafter, for convenience of description, the present invention refers to the fixed allocated resources as 'fixed resources'.

In the case of changing a fixed resource, a base station generally releases a fixed resource already allocated through signaling and allocates a new fixed resource. However, the change of fixed resources through release and reallocation requires two signaling. Therefore, if a fixed resource that is already allocated can be released through a single signaling to change a fixed resource and can support a method of allocating a new fixed resource, the system can reduce signaling overhead in operating the fixed allocation scheme. have. In this case, when a plurality of fixed resources are allocated to one terminal, the terminal should distinguish which of the plurality of fixed resources is already signaled for changing the fixed resources. However, in general, the map IE includes a MACID (Media Access Control IDentifier), which is an identifier of a terminal, but the MACID alone does not distinguish a plurality of fixed resources allocated to the same terminal. Therefore, when changing a fixed resource of a terminal assigned a plurality of fixed resources, there is a need for an alternative for recognizing a fixed resource of the plurality of fixed resources for the terminal to the terminal.

Accordingly, an object of the present invention is to provide an apparatus and method for changing a fixed resource allocated according to a fixed allocation scheme in a broadband wireless communication system.

Another object of the present invention is to provide an apparatus and method for recognizing one fixed resource to a terminal when one fixed resource of a plurality of fixed resources allocated to the same terminal is changed in a broadband wireless communication system.

According to an aspect of the present invention for achieving the above object, the operation method of a base station in a broadband wireless communication system, the process of changing at least one of the modulation and coding scheme (MCS) level, location and size of a fixed resource allocated to the terminal And setting the ACID field of the map IE to the same value as the ACID of the fixed resource, and the map IE including the ACID field and at least one field indicating the MCS level, location, and size of the fixed resource after the change. It characterized in that it comprises a process of transmitting.

In order to distinguish fixed resources of a terminal having a plurality of fixed resources in a broadband wireless communication system, the terminal is confused by using a HARQ Channel IDentifier (ACID) without including a separate fixed resource identifier field in a map Information Element (IE). You can identify one of the fixed resources that you have already allocated. In particular, when the fixed resource is to be changed, the base station and the terminal may change the MCS level, location, size, etc. of the fixed resource through one signaling without performing two signaling such as release signaling and allocation signaling.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, when it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

Hereinafter, a description will be given of a technique for changing a fixed resource allocated according to a fixed allocation scheme in a broadband wireless communication system. Hereinafter, the present invention will be described using an Orthogonal Frequency Division Multiplexing (OFDM) / Orthogonal Frequency Division Multiple Access (OFDMA) scheme as an example. The same applies to other wireless communication systems.

The frame structure of the broadband wireless communication system according to the present invention is shown in FIG.

As shown in FIG. 1, one superframe 110 is composed of a plurality of frames 120. Each frame 120 is composed of a plurality of subframes 130, and each subframe 130 is composed of a plurality of OFDMA symbols. Resource allocation is performed for resources in each subframe 130, and resources in each subframe 130 are allocated in units of a resource unit (RU) 140. That is, the terminal communicating with the base station is assigned an integer number of resource units.

Therefore, the map message is transmitted for each subframe 130. In this case, each of the map IEs indicating the resource allocation result included in the map message may include at least one of cyclic redundancy check (CRC) and scrambling using a unique sequence allocated to the terminal that should receive the map IE. Undergo treatment. For example, a media access control identifier (MACID) may be used as the unique sequence. In other words, a method of masking a CRC with the MACID or a method of adding a CRC to a map IE and then scrambling a map IE and a CRC with the MACID is used. Accordingly, each terminal identifies each map IE for its own by performing one of CRC checking and descrambling with a unique sequence assigned to each of the map IEs. This map IE encoding scheme is referred to as separate coding or MACID scrambling.

When both a hybrid automatic repeat reQuest (HARQ) technique and a fixed allocation technique are applied, the map IE includes fields as shown in Table 1 below.

Field name Bits Explanation Type MCS / Repetition Slot Offset Slot Duration ACID 3 '000'-'110': used as ACID.
'111': indicates deallocation. Other information
(Allocation Period, etc.)

In Table 1, the 'Type' field indicates the purpose of the map IE, and whether the map IE is a map IE for uplink resource allocation, a map IE for downlink resource allocation, and power control Indicates whether this is a map IE for. Therefore, the terminal determines the type and interpretation method of the fields included in the map IE according to the 'Type' field. The 'Modulation and Coding Scheme (MCS) / Repetition' field indicates the MCS level and the number of repetitions of the allocated resource. The 'Slot Offset' field indicates the start position of the allocated resource, and the 'Slot Duration' field indicates the length of the allocated resource. The 'Slot Offset' field and the 'slot Duration' field are examples of fields for indicating the location and size of a resource, and a field indicating the location and size of a resource of another type is in accordance with the intention of an embodiment of the present invention. The 'Slot Offset' field and the 'slot Duration' field may be replaced. For example, when the location and size of a resource are indicated by an index, an index field may replace the 'Slot Offset' field and the 'slot Duration' field.

The 'ACID (HARQ Channel IDentifier)' field is a field indicating an ACID for identifying HARQ processes performed through allocated resources. Here, the HARQ process means a progression process until one HARQ packet is successfully received, and the initial transmission, retransmission, combining, etc. of the one HARQ packet constitute a HARQ process. Therefore, HARQ packets belonging to the same HARQ process include the same ACID. Here, the ACID may be referred to as HARQ Process ID. That is, the ACID is an identifier for allowing the terminal to operate a plurality of HARQ processes in parallel, and a plurality of HARQ processes belonging to one terminal are given different ACIDs. Therefore, when trying to combine the initial transport packet and the retransmission packet, the receiving end combines HARQ packets having the same ACID.

In general, in order for the ACID to be used, 'start ACID' and 'number of ACID' are required. For example, when the starting ACID is 3 and the ACID number is 3, 3, 4, and 5 are cyclically used as the ACID of the fixed resource to be allocated. In other words, when the number of ACIDs is three, at most three HARQ processes are operated on one fixed resource, and the ACIDs of the three HARQ processes are set to 3, 4, and 5, respectively. Specifically, the ACID of the first HARQ process is set to 3, the ACID of the second HARQ process is set to 4, the ACID of the third HARQ process is set to 5, and when the fourth HARQ process occurs, the ACID of the fourth HARQ process is set to 3. . In the case of allocating fixed resources, the base station transmits the map IE only once, so that the terminal implicitly applies the ACIDs in the order of 3, 4, and 5. At this time, as described above, since the first HARQ process and the fourth HARQ process use the same ACID, the first HARQ process should be terminated before the fourth HARQ process starts. In other words, the HARQ packet of the first HARQ process is successfully received before the HARQ packet of the fourth HARQ process is received, and the HARQ channel corresponding to the ACID of the first HARQ process is flushed to store the HARQ packet of the fourth HARQ process. should be flushed

That is, the maximum number of HARQ retransmissions and the number of ACIDs have a function relationship. Therefore, in cyclically operating ACIDs, the number of ACIDs must be large enough so that ACIDs do not overlap. In Table 1, the 'ACID' field means a starting ACID, and a field indicating the number of ACIDs is omitted. That is, the present invention assumes that the ACID number is delivered to the terminal at the start of the fixed assignment. However, the ACID count may be represented as one field in the map IE. In addition, the number of HARQ processes and the number of ACIDs used simultaneously for the one fixed resource may be delivered in the process of the terminal and the base station opening a connection, or the broadcast channel periodically transmitted by the base station (BCH) It can be delivered via Broadcast CHannel.

In addition, in addition to the fields shown in Table 1, a 'Subpacket ID' field indicating a sequence of HARQ retransmission packets and fields for supporting a Multiple Input Multiple Output (MIMO) function may be additionally included.

The base station according to the present invention informs the terminal of a fixed resource that is changed among a plurality of fixed resources by using the 'ACID' field included in the map IE as shown in Table 1 above.

Referring to FIG. 2A, the base station 210 transmits two map IEs for fixed allocation to the terminal 220. The two map IEs indicate fixed resources of different positions and sizes, that is, fixed resource A 231 and fixed resource B 232. At this time, the ACID of the fixed resource A (231) is 1, the ACID of the fixed resource B (232) is 4. In FIG. 2A, since the number of cyclically used ACIDs is assumed to be 3, the difference between the ACID values between the two fixed resources 231 and 232 becomes 3. That is, ACIDs 1, 2 and 3 are cyclically used for the fixed resource A 231, and ACIDs 4, 5 and 6 are cyclically used for the fixed resource B 232. Accordingly, the terminal 220 continuously uses the fixed resource A 231 and the fixed resource B 232 without a separate map IE.

In the situation where the terminal 220 uses two fixed resources as shown in FIG. 2A, when the new fixed resource is additionally allocated, the base station 210 transmits a map IE including an ACID field set to a new value. . That is, as shown in FIG. 2B, the base station 210 includes an ACID set to 7 and transmits a map IE indicating the fixed resource C 233. The terminal 220 confirms that the ACID field of the received map IE is set to 7, and recognizes that it does not have a fixed resource with an ACID of 7. Accordingly, the terminal 220 determines that the map IE is a map IE for allocating a new fixed resource, and manages the fixed resource C 233 indicated by the map IE as its fixed resource. That is, the terminal 220 continuously uses the fixed resource A 231, the fixed resource B 232, and the fixed resource C 233 without a separate map IE.

In the situation where the terminal 220 uses two fixed resources as shown in FIG. 2A, when the fixed resource B 232 is changed, the base station 210 is set to the same value as the ACID of the changed fixed resource. Send a map IE that contains an ACID field.

In general, in order to change the allocated fixed resource, the base station 210 needs to release the allocated fixed resource and allocate the fixed resource again. In this case, two signaling, that is, signaling for release of fixed resources and signaling for allocation of fixed resources are required. Therefore, in order to reduce signaling overhead, one signaling must be configured such that the allocated fixed resource is implicitly released and a new fixed resource is allocated. In this case, when a plurality of fixed resources are allocated, signaling for changing the fixed resource needs to inform which one of the plurality of fixed resources is to be changed. To this end, as shown in FIG. 2C, the base station 210 transmits a map IE including an ACID field set to 4 to change the fixed resource B 232. The terminal 220 confirms that the ACID field of the received map IE is set to 4, and recognizes that the fixed resource B 232 having the ACID of 4 and the value of the ACID field of the map IE are the same. Accordingly, the terminal 220 determines that the map IE is a map IE for changing the fixed resource B 232, and the position and size of the fixed resource B 232 as indicated by the map IE. And at least one of the MCS levels. 2C illustrates an example in which the size of the fixed resource B 232 is changed. Thereafter, the terminal 220 continuously uses the fixed resource A 231 and the changed fixed resource B 232 without a separate map IE.

In the situation where the terminal 220 uses two fixed resources as shown in FIG. 2A, when the fixed resource B 232 is released, the base station 210 includes an ACID field set to 0b111 and is released. Send a map IE indicating a fixed resource. That is, as shown in FIG. 2D, the base station 210 includes an ACID field set to 0b111 to release the fixed resource B 232 and indicates the location and size of the fixed resource B 232. Send a map IE. The terminal 220 confirms that the ACID field of the received map IE is set to 0b111 and at the same time, the map IE indicates the fixed resource B 232. Accordingly, the terminal 220 determines that the map IE is a map IE for releasing the fixed resource B 232, and releases the fixed resource B 232. Thereafter, the terminal 220 continuously uses only the fixed resource A 231 without a separate map IE.

In FIG. 2D, the base station 210 uses a specific value of the ACID field to indicate release of a fixed resource. However, according to another embodiment of the present invention, a separate allocation flag field, which is not a specific value of the ACID field, may be used for releasing the fixed resource. That is, when the allocation flag field is set to 0, the map IE is for releasing the fixed resource, and accordingly, the terminal 220 releases the fixed resource indicated by the map IE. In addition, when a fixed resource is newly allocated, the base station 210 transmits a map IE including an allocation flag field set to one. That is, the map IE includes the fields shown in Table 1 and the allocation flag field, and the allocation flag field is set to 1 when allocating or changing a fixed resource and 0 when releasing the fixed resource. In addition, when the fixed resource is released, the base station 210 may set the allocation flag to 0 and set the ACID field to the ACID of the fixed resource. In this case, the problem that occurs when a fixed resource is changed among one of the plurality of fixed resources, that is, the ambiguity in which it is unknown which of the plurality of fixed resources should be released is solved.

In the embodiment described with reference to FIGS. 2A to 2D, the base station uses the ACID value set in the ACID field of the map IE as the value of the ACID field for indicating the change of the fixed resource. However, as the ACID for indicating the fixed resource change, the ACID values used in the initial fixed resource allocation as well as the circularly used ACID values may be used. That is, assuming that three ACIDs are cyclically used for one fixed resource, for example, 1 is assigned to the ACID of the fixed resource A, and in fact, 1, 2, and 3 are cyclically used as the ACID. When the ACID field of the map IE for changing the fixed resource A is set to any one of 1, 2, and 3, the terminal may determine that the fixed resource A is indicated. In other words, after assigning an ACID of 1 when allocating a fixed resource, the base station sets the ACID field of the map IE to one of 1, 2, and 3 when the fixed resource is changed. That is, assigning an ACID to 1 means that three ACIDs such as 1, 2, and 3 are allocated.

Hereinafter, the operation and configuration of a base station and a terminal that perform signaling for a fixed allocation scheme as described above will be described in detail with reference to the accompanying drawings.

3 is a flowchart illustrating an operation procedure of a base station in a broadband wireless communication system according to a first embodiment of the present invention. 3 illustrates an operation of a base station according to fixed resource allocation, change, and release considering only one terminal. In addition, in FIG. 3, it is assumed that the present invention uses a 3-bit ACID.

Referring to FIG. 3, the base station performs scheduling for fixed resources of the terminal in step 301. That is, the base station allocates fixed resources or changes or releases the allocated fixed resources according to the generation, modification and deletion of the service flow of the terminal. Here, changing the fixed resource means changing at least one of an MCS level, a position, and a size of the fixed resource. In particular, when allocating fixed resources, the base station allocates one of the ACIDs not assigned as the ACID of the fixed resources of the terminal to the newly allocated fixed resources. However, the base station excludes 0b111. That is, the base station allocates one of the values 0b000 to 0b110 except for the ACID values currently assigned to the terminal as the ACID. In this case, the allocated ACID values include not only the starting ACID value set in the ACID field of the map IE used in the initial allocation of the fixed resource, but also the starting ACID value and at least one ACID used together in a cyclic manner. Here, since the 0b111 is used to inform the release of the fixed resource, it is excluded from the value of the assignable ACID.

In step 303, the base station determines whether a new fixed resource exists. In other words, the base station determines whether a new fixed resource is allocated as a result of the scheduling.

If the new fixed resource exists, the base station proceeds to step 305 and sets one of the unassigned ACIDs to the ACID field of the map IE. That is, the base station sets the ACID allocated to the fixed resource to the ACID field of the map IE in step 301.

In step 307, the base station generates a map IE indicating a new fixed resource. Specifically, the base station sets the MCS / Repetition field of the map IE. The base station sets the slot offset field and the slot duration field to a value indicating the position and size of the new fixed resource. However, when the location of the fixed resource is indicated by the index, the base station sets the index field to a value indicating the location and size of the new fixed resource. In addition, the base station sets an Allocation Period field, a Subpacket ID field, and fields indicating MIMO related information.

In step 303, if the new fixed resource does not exist, the base station proceeds to step 309 and checks whether there is a changed fixed resource. In other words, the base station determines whether at least one of the MCS level, location, and size of the fixed resource allocated as a result of the scheduling is changed.

If the changed fixed resource exists, the base station proceeds to step 311 and sets the ACID field of the map IE to the ACID of the changed fixed resource. In other words, the base station sets the same value as the ACID of the changed fixed resource to the ACID field of the map IE so that the terminal can identify the changed fixed resource. Here, the ACID of the changed fixed resource is not only a starting ACID value that is set in the ACID field of the map IE used in the initial allocation of the changed fixed resource, but also the starting ACID value and at least one ACID used in a circular manner. Include all of them. That is, the base station sets the ACID field to the same value as one of at least one ACID used for the changed fixed resource.

In step 313, the base station generates a map IE indicating a fixed resource after the change. Specifically, the base station sets the Slot Offset field, Slot Duration field, and MCS / Repetation field to values indicating the location, size, and MCS level of the fixed resource after the change. However, when the location of the fixed resource is indicated by the index, the base station sets the index field to a value indicating the location and size of the fixed resource after the change.

In step 309, if the changed fixed resource does not exist, the base station proceeds to step 315 and checks whether there is a fixed resource released. In other words, the base station determines whether the allocated fixed resource is released as a result of the scheduling.

If there is the released fixed resource, the base station proceeds to step 317 and sets the ACID field of the map IE to 0b111. In other words, the base station sets the ACID field of the map IE to 0b111 so that the terminal can recognize that the map IE is for releasing fixed resources. Here, 0b111 is used as the value of the ACID field defined for the release of the fixed resource, and the value of the ACID field defined for the release of the fixed resource may vary depending on the intention of the practitioner of the present invention. Can be.

In step 319, the base station generates a map IE indicating the released fixed resource. Specifically, the base station sets the Slot Offset field and the Slot Duration field to a value indicating the position and size of the released fixed resource. However, when the location of the fixed resource is indicated by the index, the base station sets the index field to a value indicating the location and size of the released fixed resource.

As described above, the base station repeats steps 303 to 319 and generates at least one map IE for a fixed resource newly allocated, changed, or released as a result of the scheduling of step 301. In step 315, if there is no fixed resource to be released, that is, when all map IEs are generated, the base station proceeds to step 321 and transmits the at least one map IE. In this case, the base station scrambles the at least one map IE MACID using the MACID of the terminal. Subsequently, the base station proceeds to step 323 to communicate with the terminal through a fixed resource currently present. However, if there is no fixed resource allocated to the terminal, step 323 is omitted.

4 illustrates an operation procedure of a terminal in a broadband wireless communication system according to a first embodiment of the present invention. 4, it is assumed that the present invention uses a 3-bit ACID.

Referring to FIG. 4, the terminal determines whether a map IE for fixed allocation is received in step 401. In other words, the terminal checks whether a map IE including a Type field set to a value indicating fixed allocation is received.

When the map IE for the fixed allocation is received, the terminal proceeds to step 403 and determines whether the value of the ACID field of the map IE is 0b111. That is, the terminal determines whether the value of the ACID field is a value indicating release of the fixed resource. Here, 0b111 is used as the value of the ACID field defined for the release of the fixed resource, and the value of the ACID field defined for the release of the fixed resource may vary depending on the intention of the practitioner of the present invention. Can be.

If the value of the ACID field is 0b111, the terminal proceeds to step 405 to release the fixed resource indicated by the map IE. Specifically, the terminal checks the position and size of the fixed resource indicated by the Slot Offset field and the Slot Duration field of the map IE, and releases the fixed resource of the identified position and size. However, when the location of the fixed resource is indicated by the index, the terminal checks the location and size of the fixed resource indicated by the index field, and releases the fixed resource of the identified location and size.

In step 403, if the value of the ACID field is not 0b111, the terminal proceeds to step 407 and determines whether the value of the ACID field is a new ACID. That is, the terminal checks whether the value of the ACID field is a new ACID instead of the ACID of the fixed resource among the values of 0b000 to 0b110. At this time, if there is no fixed resource held by the terminal, the value of the ACID field is always a new ACID.

If the value of the ACID field is a new ACID, the terminal proceeds to step 409 and sets the resource indicated by the map IE as a new fixed resource. Specifically, the terminal checks the location and size of the resource indicated by the Slot Offset field and the Slot Duration field of the map IE, and sets the resource of the identified location and size as its fixed resource. However, if the location of the fixed resource is indicated by the index, the terminal checks the location and size of the resource indicated by the index field, and sets the resource of the identified location and size as its fixed resource. Accordingly, the terminal fixedly uses the resources of the identified location and size.

In step 407, if the value of the ACID field is not a new ACID, the terminal proceeds to step 411 and checks whether the value of the ACID field is the ACID of the fixed resource. That is, the terminal checks whether the value of the ACID field is the same as the ACID of the fixed resource. Here, the ACID of the retained fixed resource includes not only the start ACID value set in the ACID field of the map IE used when the reserved resource is initially allocated, but also the start ACID value and at least one ACID that is cyclically used together. Include.

If the value of the ACID field is the ACID of the fixed resource, the terminal proceeds to step 413 to change the fixed resource having the same ACID as the value of the ACID field. In other words, the terminal recognizes that the map IE is for changing the fixed resource, and changes at least one of the MCS level, location, and size of the fixed resource indicated by the map IE. Specifically, the terminal releases a fixed resource having the same ACID as the value of the ACID field, and sets the resource indicated by the map IE as a new fixed resource. At this time, the ACID of the new fixed resource is the ACID of the released fixed resource.

Thereafter, the terminal proceeds to step 415 to communicate with the base station through the fixed resources. However, if there is no fixed resource allocated to the terminal, step 415 is omitted.

5 is a flowchart illustrating an operation procedure of a base station in a broadband wireless communication system according to a second embodiment of the present invention. FIG. 5 illustrates an operation of a base station according to fixed resource allocation, modification, and release considering only one terminal. In addition, in FIG. 5, it is assumed that the present invention uses a 3-bit ACID.

Referring to FIG. 5, the base station performs scheduling of fixed resources in step 501. That is, the base station allocates a fixed resource according to the generation, modification and deletion of a service flow, or changes or releases the allocated fixed resource. Here, changing the fixed resource means changing at least one of an MCS level, a position, and a size of the fixed resource. In particular, when allocating fixed resources, the base station allocates one of the ACIDs not assigned as the ACID of the fixed resources of the terminal to the newly allocated fixed resources. That is, the base station allocates one of the remaining values other than the ACID values currently assigned to the terminal among the values of 0b000 to 0b111 as the ACID. In this case, the allocated ACID values include not only the starting ACID value set in the ACID field of the map IE used in the initial allocation of the fixed resource, but also the starting ACID value and at least one ACID used together in a cyclic manner.

In step 503, the base station determines whether a new fixed resource exists. In other words, the base station determines whether a new fixed resource is allocated as a result of the scheduling.

If the new fixed resource exists, the base station proceeds to step 505 and sets one of the unassigned ACIDs to the ACID field of the map IE. That is, the base station sets the ACID allocated to the fixed resource to the ACID field of the map IE in step 501.

In step 507, the base station sets the allocation flag field to one. That is, the base station sets the allocation flag field to 1 to inform the terminal that the map IE is for allocation or modification of fixed resources. Here, the allocation flag field set to 1 is used as a value indicating the allocation or change of the fixed resource, and according to the intention of the inventor of the present invention, the allocation flag field set to 0 indicates the allocation or change of the fixed resource. Can be used as a value.

After setting the allocation flag field, the base station proceeds to step 509 to generate a map IE indicating a new fixed resource. Specifically, the base station sets the MCS / Repetition field of the map IE. The base station sets the slot offset field and the slot duration field to a value indicating the position and size of the new fixed resource. However, when the location of the fixed resource is indicated by the index, the base station sets the index field to a value indicating the location and size of the new fixed resource. In addition, the base station sets an Allocation Period field, a Subpacket ID field, and fields indicating MIMO related information.

In step 503, if the new fixed resource does not exist, the base station proceeds to step 511 and determines whether there is a changed fixed resource. In other words, the base station determines whether at least one of the MCS level, location, and size of the fixed resource allocated as a result of the scheduling is changed.

If the changed fixed resource exists, the base station proceeds to step 513 and sets the ACID field of the map IE to the ACID of the changed fixed resource. In other words, the base station sets the same value as the ACID of the changed fixed resource to the ACID field of the map IE so that the terminal can identify the changed fixed resource. Here, the ACID of the changed fixed resource is not only a starting ACID value that is set in the ACID field of the map IE used in the initial allocation of the changed fixed resource, but also the starting ACID value and at least one ACID used in a circular manner. Include all of them. That is, the base station sets the ACID field to the same value as one of at least one ACID used for the changed fixed resource.

After setting the ACID field, the base station proceeds to step 515 to set the assignment flag field to 1. That is, the base station sets the allocation flag field to 1 to inform the terminal that the map IE is for allocation or modification of fixed resources. Here, the allocation flag field set to 1 is used as a value indicating the allocation or change of the fixed resource, and according to the intention of the inventor of the present invention, the allocation flag field set to 0 indicates the allocation or change of the fixed resource. Can be used as a value.

In step 517, the base station generates a map IE indicating a fixed resource after the change. Specifically, the base station sets the Slot Offset field, Slot Duration field, and MCS / Repetation field to values indicating the location, size, and MCS level of the fixed resource after the change. However, when the location of the fixed resource is indicated by the index, the base station sets the index field to a value indicating the location and size of the fixed resource after the change.

In step 511, if the changed fixed resource does not exist, the base station proceeds to step 519 and determines whether there is a fixed resource released. In other words, the base station determines whether the allocated fixed resource is released as a result of the scheduling.

If the released fixed resource exists, the base station proceeds to step 521 and sets the allocation flag field to zero. That is, the base station sets the allocation flag field to 0 to inform the terminal that the map IE is to release the fixed resource. Here, it is an example that the allocation flag field set to 0 is used as a value indicating release of the fixed resource, and according to an intention of an embodiment of the present invention, the allocation flag field set to 1 may be used as a value indicating release of the fixed resource. have. Additionally, in order to explicitly indicate the fixed resource to be released, the base station may set the ACID field of the map IE to the ACID of the fixed resource to be released.

In step 523, the base station generates a map IE indicating the released fixed resource. Specifically, the base station sets the Slot Offset field and the Slot Duration field to a value indicating the position and size of the released fixed resource. However, when the location of the fixed resource is indicated by the index, the base station sets the index field to a value indicating the location and size of the released fixed resource.

As described above, the base station repeats steps 503 to 523 and generates at least one map IE for a fixed resource newly allocated, changed, or released as a result of the scheduling of step 501. In step 523, if there is no fixed resource to be released, that is, when all map IEs have been generated, the base station proceeds to step 525 and transmits the at least one map IE. Subsequently, the base station proceeds to step 527 and performs communication with the terminal through a fixed resource that currently exists. However, if there is no fixed resource allocated to the terminal, step 527 is omitted.

6 illustrates an operation procedure of a terminal in a broadband wireless communication system according to a second embodiment of the present invention. In FIG. 6, the present invention assumes a case of using a 3-bit ACID.

Referring to FIG. 6, the terminal determines whether a map IE for fixed allocation is received in step 601. In other words, the terminal checks whether a map IE including a Type field set to a value indicating fixed allocation is received.

When the map IE for the fixed allocation is received, the terminal proceeds to step 603 to check the value of the allocation flag field of the map IE. That is, the terminal checks whether the map IE is for releasing a fixed resource or for allocating or changing a fixed resource. In other words, if the allocation flag field is 0, the terminal recognizes that the map IE is for releasing the fixed resource. If the allocation flag field is 1, the terminal IE assigns or changes the fixed resource. Be aware that Here, the allocation flag field set to 0 is used as a value indicating release of the fixed resource, and the allocation flag field set to 1 is used as a value indicating allocation or change of the fixed resource. Therefore, according to the intention of the practitioner of the present invention, an allocation flag field set to 0 may be used as a value indicating allocation or change of fixed resources, and an allocation flag field set to 1 may be used as a value indicating release of fixed resources.

If the value of the allocation flag field is 0, the terminal proceeds to step 605 to release the fixed resource indicated by the map IE. Specifically, the terminal checks the position and size of the fixed resource indicated by the Slot Offset field and the Slot Duration field of the map IE, and releases the fixed resource of the identified position and size. However, when the location of the fixed resource is indicated by the index, the terminal checks the location and size of the fixed resource indicated by the index field, and releases the fixed resource of the identified location and size.

In step 603, if the value of the allocation flag field is 1, the terminal proceeds to step 607 and determines whether the value of the ACID field of the map IE is a new ACID. That is, the terminal checks whether the value of the ACID field is a new ACID instead of the ACID of the fixed resource among the values of 0b000 to 0b111. At this time, if there is no fixed resource held by the terminal, the value of the ACID field is always a new ACID.

If the value of the ACID field is a new ACID, the terminal proceeds to step 609 and sets the resource indicated by the map IE as a new fixed resource. Specifically, the terminal checks the location and size of the resource indicated by the Slot Offset field and the Slot Duration field of the map IE, and sets the resource of the identified location and size as its fixed resource. However, if the location of the fixed resource is indicated by the index, the terminal checks the location and size of the resource indicated by the index field, and sets the resource of the identified location and size as its fixed resource. Accordingly, the terminal fixedly uses the resources of the identified location and size.

In step 607, if the value of the ACID field is not a new ACID, the terminal proceeds to step 611 to determine whether the ACID of the fixed resource held by the value of the ACID field. That is, the terminal checks whether the value of the ACID field is the same as the ACID of the fixed resource. Here, the ACID of the retained fixed resource includes not only the start ACID value set in the ACID field of the map IE used when the reserved resource is initially allocated, but also the start ACID value and at least one ACID that is cyclically used together. Include.

If the value of the ACID field is the ACID of the fixed resource, the terminal proceeds to step 613 to change the fixed resource having the same ACID as the value of the ACID field. In other words, the terminal recognizes that the map IE is for changing the fixed resource, and changes at least one of the MCS level, location, and size of the fixed resource indicated by the map IE. Specifically, the terminal releases a fixed resource having the same ACID as the value of the ACID field, and sets the resource indicated by the map IE as a new fixed resource. At this time, the ACID of the new fixed resource is the ACID of the released fixed resource.

Thereafter, the terminal proceeds to step 615 to communicate with the base station through the fixed resources. However, if there is no fixed resource allocated to the terminal, step 615 is omitted.

7 is a block diagram of a base station in a broadband wireless communication system according to an exemplary embodiment of the present invention.

7 is a block diagram of a base station in a broadband wireless communication system according to an exemplary embodiment of the present invention.

As shown in FIG. 7, the base station includes a subcarrier mapper 702, an OFDM modulator 704, a radio frequency (RF) transmitter 706, an RF receiver 708, an OFDM demodulator 710, and a subcarrier dimapping. Machine 712, a data processor 714, a message generator 716, a message interpreter 718, and a controller 720.

The subcarrier mapper 702 maps data signals provided from the data processor 714 and message signals provided from the message generator 718 to subcarriers. The OFDM modulator 704 converts the signals mapped to the subcarriers into a time domain signal through an inverse fast fourier transform (IFFT) operation, and configures OFDM symbols by inserting a cyclic prefix (CP). The RF transmitter 708 upconverts the OFDM symbols into an RF band signal and then transmits the RF band signal through an antenna. The RF receiver 710 converts an RF band signal received through an antenna into a baseband signal. The OFDM demodulator 712 divides the baseband signal into OFDM symbol units, removes a CP, and restores signals for each subcarrier through a fast fouriter transform (FFT) operation. The subcarrier demapper 712 divides the signals for each subcarrier into processing units. The subcarrier mapper 712 provides data signals to the data processor 714 and message signals to the message interpreter 716. The data processor 714 recovers the received data bit stream by demodulating and channel decoding the data signals, and generates transmit data signals by channel encoding and modulating the transmit data bit stream.

The message interpreter 716 restores a message bit string from the message signals received from the terminal. The message interpreter 716 checks the information included in the message by interpreting the message bit string, and provides the checked information to the controller 720. The message generator 718 configures a message bit string including information provided from the controller 720 and generates physical message signals from the message bit string.

In particular, the message generator 718 generates a map IE for allocating, changing or releasing the fixed resource according to the scheduling result of the fixed resource provided from the controller 720. In detail, the message generator 718 sets at least one of an ACID field, an MCS / Repetition field, a Slot Offset field, and a Slot Duration field of a map IE, and additionally includes an Allocation Period field, a Subpacket ID field, and MIMO related information. At least one of the notifying fields may be selectively set. Here, the Slot Offset field and the Slot Duration field are used to indicate the position and size of a fixed resource, and indicate the position and size of a newly allocated fixed resource when the fixed resource is allocated and the fixed after the change when the fixed resource is changed. Indicate the location and size of the resources, and the location and size of the fixed resources released upon release of the fixed resources. However, according to another embodiment of the present invention, when the location of the fixed resource is indicated by the index, the Slot Offset field and the Slot Duration field are replaced by the index field. Among the fields of the map IE listed above, the process of setting the ACID field depends on the allocation, modification or release of the fixed resource. The message generator 718 scrambles the map IE using the MACID of the receiving terminal.

The ACID field setting procedure in the case of the first embodiment of the present invention is as follows. In case of allocating a fixed resource, the message generator 718 sets one of the ACIDs not assigned as the ACID of the fixed resource of the terminal to the ACID field of the map IE. In this case, the message generator 718 excludes 0b111. That is, the message generator 718 sets one of the values 0b000 to 0b110, which are not currently allocated as the ACID of the fixed resource of the terminal, to the ACID field. When changing a fixed resource, the message generator 718 sets the ACID field to the ACID of the fixed resource to be changed. Here, the ACID of the changed fixed resource is not only a starting ACID value that is set in the ACID field of the map IE used in the initial allocation of the changed fixed resource, but also the starting ACID value and at least one ACID used in a circular manner. Include all of them. When releasing a fixed resource, the message generator 718 sets the ACID field to 0b111. Here, 0b111 is used as the value of the ACID field defined for the release of the fixed resource, and the value of the ACID field defined for the release of the fixed resource may vary depending on the intention of the practitioner of the present invention. Can be.

The procedure of setting an ACID field in the second embodiment of the present invention is as follows. According to the second embodiment of the present invention, the map IE further includes an assignment flag field. When allocating a fixed resource, the message generator 718 allocates an ACID of one of the ACIDs not allocated as the ACID of the fixed resource of the terminal to the newly allocated fixed resource, and sets the allocation flag field to one. When changing the fixed resource, the message generator 718 sets the ACID field to the ACID of the changed fixed resource and sets the allocation flag field to one. Here, the ACID of the changed fixed resource is not only a starting ACID value that is set in the ACID field of the map IE used in the initial allocation of the changed fixed resource, but also the starting ACID value and at least one ACID used in a circular manner. Include all of them. When releasing a fixed resource, the message generator 718 does not set an ACID field, but sets the allocation flag field to zero. Here, the allocation flag field set to 0 is used as a value indicating release of the fixed resource, and the allocation flag field set to 1 is used as a value indicating allocation or change of the fixed resource. Therefore, according to the intention of the practitioner of the present invention, an allocation flag field set to 0 may be used as a value indicating allocation or change of fixed resources, and an allocation flag field set to 1 may be used as a value indicating release of fixed resources.

The controller 720 controls the overall function of the base station. For example, the controller 720 controls the subcarrier demapping unit 712 to extract data signals for each terminal according to a resource allocation result, and the subcarrier mapping to map data signals for each terminal according to the resource allocation result. Control the machine 702. In addition, the controller 720 performs a process corresponding to the information identified by the message interpreter 718, and provides the message generator 716 with information included in the transmission message. In addition, the scheduler 722 in the controller 720 allocates resources to the terminals. In particular, the scheduler 722 allocates fixed resources to the terminals according to a fixed allocation scheme. That is, the scheduler 722 allocates a fixed resource according to the creation, modification and deletion of a service flow, or changes or releases the allocated fixed resource. In particular, when allocating a fixed resource, the scheduler 722 allocates one of the remaining ACID values to the newly allocated fixed resource except for the ACIDs allocated as the ACID of the fixed resource of the terminal. In this case, the allocated ACID values include not only the starting ACID value set in the ACID field of the map IE used in the initial allocation of the fixed resource, but also the starting ACID value and at least one ACID used together in a cyclic manner. In addition, the resource status manager 724 in the controller 720 manages the status of fixed resources allocated to the terminals.

8 is a block diagram of a terminal in a broadband wireless communication system according to an exemplary embodiment of the present invention.

As shown in FIG. 8, the terminal includes a radio frequency (RF) receiver 802, an OFDM demodulator 804, a subcarrier demapper 806, a data processor 808, a subcarrier mapper 810, and an OFDM. The modulator 812 includes an RF transmitter 814, a message generator 816, a message interpreter 818, and a controller 820.

The RF receiver 802 converts an RF band signal received through an antenna into a baseband signal. The OFDM demodulator 804 divides the baseband signal into OFDM symbol units, removes a CP, and restores signals for each subcarrier through an FFT operation. The subcarrier demapper 806 divides the signals for each subcarrier into processing units. The subcarrier mapper 806 provides data signals to the data processor 808 and message signals to the message interpreter 816. The data processor 808 recovers a data reception bit stream by demodulating and channel decoding the data signals, and generates transmission data signals by channel coding and modulating the transmission data bit stream. The subcarrier mapper 810 maps the data signals provided from the data processor 808 and the message signals provided from the message generator 818 to subcarriers. The OFDM modulator 812 configures OFDM symbols by converting signals mapped to the subcarriers into time-domain signals through an IFFT operation and inserting CPs. The RF transmitter 814 upconverts the OFDM symbols into an RF band signal and then transmits the RF band signal through an antenna.

The message generator 816 composes a message bit string including information provided from the controller 820 and generates physical message signals from the message bit string. The message interpreter 818 recovers the message bit string from the message signals received from the base station. In addition, the message interpreter 818 confirms the information included in the message by interpreting the message bit string, and provides the confirmed information to the controller 820.

In particular, the message interpreter 818 identifies fixed resources that are allocated, changed or released by interpreting a map IE for allocating, changing, or releasing fixed resources. In detail, the message interpreter 818 checks the map IE for the terminal by performing MACID descrambling using the MACID of the terminal, and then uses the at least one of an ACID field or an allocation flag field of the map IE. The purpose of the map IE is to be determined, that is, whether to allocate, change, or release fixed resources, and to identify the fixed resources indicated by the Slot Offset field and the Slot Duration field. Here, the Slot Offset field and the Slot Duration field are used to indicate the position and size of a fixed resource, and indicate the position and size of a newly allocated fixed resource when the fixed resource is allocated and the fixed after the change when the fixed resource is changed. Indicate the location and size of the resources, and the location and size of the fixed resources released upon release of the fixed resources. However, according to another embodiment of the present invention, when the location of the fixed resource is indicated by the index, the Slot Offset field and the Slot Duration field are replaced by the index field. In addition, the message interpreter 818 may identify at least one of an Allocation Period field, a Subpacket ID field, and a field indicating MIMO related information. The process of determining, by the map IE, the purpose of the fixed resource through at least one of the ACID field and the allocation flag field is as follows.

According to the first embodiment of the present invention, the purpose of the map IE is determined through the ACID field. If the value of the ACID field is 0b111, the message interpreter 818 determines that the map IE is for releasing a fixed resource. Accordingly, the message interpreter 818 checks the position and size of the fixed resource indicated by the map IE, and then informs the controller 820 that the fixed resource of the identified position and size has been released. Here, 0b111 is used as the value of the ACID field defined for the release of the fixed resource, and the value of the ACID field defined for the release of the fixed resource may vary depending on the intention of the practitioner of the present invention. Can be. If the value of the ACID field is a new ACID that is different from the ACID of the fixed resource, the message interpreter 818 determines that the map IE is for allocation of the fixed resource. Accordingly, the message parser 818 checks the location and size of the resource indicated by the map IE, and then determines that the resource of the identified location and size is allocated as a new fixed resource. 820). If the value of the ACID field is the same as the ACID of the fixed resource, the message interpreter 818 determines that the map IE is for changing the fixed resource. Accordingly, the position, size, and MCS of the fixed resource indicated by the map IE is checked, and the position, size, and MCS of the fixed resource having the same ACID as the value of the ACID field is identified. Informs that the level has been changed. Here, the ACID of the retained fixed resource includes not only the start ACID value set in the ACID field of the map IE used when the reserved resource is initially allocated, but also the start ACID value and at least one ACID that is cyclically used together. Include.

According to the second embodiment of the present invention, the purpose of the map IE is determined through the ACID field and the assignment flag field. If the value of the allocation flag field is 0, the message interpreter 818 determines that the map IE is for releasing a fixed resource. Accordingly, the message interpreter 818 checks the position and size of the fixed resource indicated by the map IE, and then informs the controller 820 that the fixed resource of the identified position and size has been released. If the value of the allocation flag field is 1, the message parser 818 determines that the map IE is for allocation or modification of a fixed resource. Accordingly, the message parser 818 checks the ACID field of the map IE. As a result of the check, if the value of the ACID field is a new ACID that is different from the ACID of the fixed resource, the message parser 818 determines that the map IE is for allocation of the fixed resource. Accordingly, the message parser 818 checks the location and size of the resource indicated by the map IE, and then determines that the resource of the identified location and size is allocated as a new fixed resource. 820). If the value of the ACID field is the same as the ACID of the fixed resource, the message interpreter 818 determines that the map IE is for changing the fixed resource. Accordingly, the position, size, and MCS of the fixed resource indicated by the map IE is checked, and the position, size, and MCS of the fixed resource having the same ACID as the value of the ACID field is identified. Informs that the level has been changed. Here, the ACID of the retained fixed resource includes not only the start ACID value set in the ACID field of the map IE used when the reserved resource is initially allocated, but also the start ACID value and at least one ACID that is cyclically used together. Include.

The controller 820 controls the overall function of the terminal. For example, the controller 820 controls the subcarrier mapper 806 to extract data signals from the allocated resources identified by the message parser 816 and transmits data signals to the allocated resources. The subcarrier mapper 810 is controlled to control the subcarrier mapper 810. In addition, the controller 820 performs a process corresponding to the information identified by the message interpreter 816, and provides the message generator 818 with information included in the transmission message. In addition, the resource status manager 822 in the controller 820 may determine the fixed resource status allocated to the terminal according to the contents of the map IE for allocating, changing, or releasing the fixed resource interpreted by the message interpreter 816. Manage.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined not only by the scope of the following claims, but also by the equivalents of the claims.

1 is a diagram illustrating a frame structure of a broadband wireless communication system according to the present invention;

2A to 2D are diagrams showing examples of signaling for allocating, changing and releasing fixed resources in a broadband wireless communication system according to the present invention;

3 is a diagram illustrating an operation procedure of a base station in a broadband wireless communication system according to a first embodiment of the present invention;

4 is a diagram illustrating an operation procedure of a terminal in a broadband wireless communication system according to a first embodiment of the present invention;

5 is a diagram illustrating an operation procedure of a base station in a broadband wireless communication system according to a second embodiment of the present invention;

6 is a diagram illustrating an operation procedure of a terminal in a broadband wireless communication system according to a second embodiment of the present invention;

7 is a block diagram of a base station in a broadband wireless communication system according to an embodiment of the present invention;

8 is a block diagram of a terminal in a broadband wireless communication system according to an exemplary embodiment of the present invention.

Claims (7)

A method of operating a base station in a broadband wireless communication system, Changing at least one of a Modulation and Coding Scheme (MCS) level, location, and size of a fixed resource allocated to the terminal; Setting the ACID field of the map IE to the same value as the HARQ Channel IDentifier (ACID) of the fixed resource; And transmitting the map IE including the ACID field and at least one field indicating the MCS level, location, and size of the fixed resource after the change. The method of claim 1, Releasing the fixed resource allocated to the terminal; Setting the ACID field of the Map IE to a value defined for the release instruction; And transmitting the map IE including the ACID field and at least one field indicating the location and size of the fixed resource. The method of claim 1, Allocating a fixed resource to the terminal; Allocating a value defined for the release instruction and a value different from an ACID of at least one fixed resource allocated to the terminal as the ACID of the fixed resource; Setting an ACID field of a map IE as an ACID of the fixed resource; And transmitting a map IE including the ACID field and at least one field indicating the MCS level, location, and size of the fixed resource. The method of claim 1, The map IE includes an allocation flag field for distinguishing allocation or change of fixed resources and release of fixed resources. And changing at least one of an MCS level, a location, and a size of the fixed resource allocated to the terminal, and then setting the allocation flag field to a value defined for allocation or change. The method of claim 1, The map IE includes an allocation flag field for distinguishing allocation or change of fixed resources and release of fixed resources. Releasing the fixed resource allocated to the terminal; Setting the ACID field of the Map IE to a value defined for the release instruction; Setting the allocation flag field to a value defined for release; Transmitting the map IE including the ACID field, the allocation flag field and at least one field indicating the location and size of the fixed resource. The method of claim 1, The map IE includes an allocation flag field for distinguishing allocation or change of fixed resources and release of fixed resources. Allocating a fixed resource to the terminal; Allocating a value defined for the release instruction and a value different from an ACID of at least one fixed resource allocated to the terminal as the ACID of the fixed resource; Setting an ACID field of a map IE as an ACID of the fixed resource; Setting the allocation flag field to a value defined for allocation or change; And transmitting a map IE including the ACID field, the allocation flag field, and at least one field indicating the MCS level, location, and size of the fixed resource. The method of claim 1, ACID of the fixed resource, And a starting ACID value set in the ACID field of the map IE used at the time of initial allocation of the fixed resource and at least one ACID used circularly.

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