KR20050114165A - Method for transmitting for controlling information in a broadband wireless access system - Google Patents

Abstract

The present invention relates to a method for transmitting control information in a wireless communication system, and more particularly to a method for transmitting control information in a broadband wireless communication system. The present invention discloses a method for more efficiently transmitting and receiving MIMO control information when it is transmitted.

A method according to the first aspect of the present invention is a multiple input multiple output in a broadband wireless access system comprising a wireless terminal and a base station capable of transmitting a burst message using the multiple input multiple output (MIMO) scheme with the wireless terminal. A method for transmitting control information of a terminal, comprising: scheduling burst messages when a burst message to be transmitted to the terminals is generated, determining a burst message to be included in a map message according to a scheduling result, and Constructing and transmitting a map information element for transmitting the control information of the multi-input multiple-output scheme when the burst message of the multi-input multiple output scheme exists in the burst message to be included.

Description

TECHNICAL FOR TRANSMITTING FOR CONTROLLING INFORMATION IN A BROADBAND WIRELESS ACCESS SYSTEM}

The present invention relates to a method for transmitting control information in a wireless communication system, and more particularly to a method for transmitting control information in a broadband wireless communication system.

In general, a wireless communication system is a typical mobile communication system based on a voice service. In the wireless communication system, due to the development of the communication industry and the increasing demand of users for Internet services, a system capable of delivering data at high speed has been introduced one after another to accelerate commercialization. However, a wireless communication system mainly developed for the voice service has a relatively narrow data transmission bandwidth, so that a large amount of resources must be allocated to transmit high speed data. Therefore, there is a problem that the fee for using the data service is expensive. Therefore, the IEEE 802.16 standardization group of the Institute of Electrical and Electronics Engineers (IEEE), one of the international standardization organizations, is a standard for providing wireless broadband Internet services to fixed terminals. The enactment is in progress.

According to the IEEE 802.16d standard, the bandwidth of the data is wider than that of the wireless communication technology for voice service, so that a large amount of data can be transmitted in a short time. In addition, the IEEE 802.16d standard allows all users to share a channel so that the channel can be used more efficiently than a wireless communication technology for voice service. That is, in the system conforming to the IEEE 802.16d standard, all users connected to the base station share and use a common channel. In the system, a period in which each user uses a channel may be divided into an uplink frame and a downlink frame, and the use of every uplink frame and the downlink frame is allocated by the base station. Therefore, the base station of the system should inform the uplink and downlink access information so that each user can divide the channel for each frame. In IEEE 802.16d, access information is divided into uplink access information and downlink access information, and a map (MAP) message, which is uplink access information and downlink access information, is transmitted to every user at the beginning of each frame. The MAP message is composed of a number of various types of MAP information elements.

Meanwhile, in the IEEE 802.16d standardization group, an attempt has been made to obtain high frequency efficiency by applying transmit diversity or spatial multiplexing. The methods used to apply these methods are the transmit diversity and the spatial multiplexing method for transmitting multiple data using multiple antennas. That is, the MIMO method is applied. As described above, when the MIMO scheme is applied in the IEEE 802.16d system, the base station needs to inform each terminal of the MIMO transmission scheme. As described above, in order to transmit a transmission method of MIMO, the base station must transmit a MIMO control signal to each terminal through a MAP message.

However, providing transmission diversity and spatial multiplexing using MIMO is not supported by the previous standard IEEE P802.16-REVd / D2-2003. Therefore, to increase transmission efficiency, a method for delivering MIMO information for applying transmission diversity and spatial multiplexing is needed. Accordingly, MIMO support has been added to IEEE P802.16-REVd / D5-2004 to support the transmit diversity and spatial multiplexing scheme. This MIMO support scheme can achieve high frequency efficiency when applied to the physical layer.

However, the MIMO support function is a function of installing a plurality of antennas in a transmitter and a receiver and obtaining transmit diversity and spatial multiplexing effects from the plurality of antennas. In order to use this function, the base station must efficiently transmit the MIMO control signal to the terminal. However, the proposed MIMO control signal transmission method together with the MIMO supporting function is transmitted to both the MIMO supporting terminal and the terminal which does not support the MIMO, and is mixed with other control signals other than the MIMO control signal. Therefore, there is a problem in that overhead increases when the MIMO control signal is transmitted. This acts as a factor to lower the band efficiency.

Accordingly, an object of the present invention is to provide a method for transmitting control information for transmitting applied control information when applying transmission diversity and spatial multiplexing.

Another object of the present invention is to provide a method for transmitting MIMO control information when the MIMO scheme is applied in a broadband wireless access communication system.

Another object of the present invention is to provide a method for transmitting control information that can increase bandwidth use efficiency when delivering MIMO control information.

A method according to the first aspect of the present invention for achieving the above object, a broadband wireless connection comprising a wireless terminal and a base station capable of transmitting a burst message with the wireless terminal using a multiple input multiple output (MIMO) scheme. A method for transmitting control information of the multi-input multi-output in a system, the method comprising: scheduling burst messages when a burst message to be transmitted to the terminals is generated and determining a burst message to be included in a MAP message according to a scheduling result. And constructing and transmitting a map information element for transmitting the control information of the multi-input multiple-output scheme when the burst message of the multi-input multiple output scheme exists in the burst message to be included in the map message.

The present invention according to the second aspect for achieving the above object in the broadband wireless access system comprising a wireless terminal and a base station capable of transmitting a burst message using the multiple terminal multiple output (MIMO) scheme with the wireless terminal; A method for receiving when control information of a multiple input multiple output is transmitted, when receiving a MAP message from the base station, inspects burst messages included in the map message, and inputs the multiple input multiplex to the burst message. Checking whether an output control information map information element exists; and when the terminal can perform a multiple input multiple output function when the multiple input multiple output control information map information element exists, the multiple input multiple output control. Information and the order in which burst messages are received by the multiple input multiple output function And a process of receiving a burst message according to the checked result, and decoding the same according to the multiple input multiple output control information.

DETAILED DESCRIPTION A detailed description of preferred embodiments of the present invention will now be described with reference to the accompanying drawings. In addition, it should be noted that the same components are denoted by the same reference numerals and symbols as much as possible even though they are shown in different drawings. In addition, in the following description of the present invention, if 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.

The present invention described below relates to access information elements and related processing procedures that can efficiently deliver MIMO control signals using downlink access information and uplink access information of a medium (Medium Access Control: MAC) layer. Will be described. In describing the procedure, the present invention newly defines the format of an efficient MAP information element having a low overhead, and defines a series of operations in which a MAP message of this format is generated and interpreted at the base station and the user terminal, respectively.

First, the configuration of the MAP information element for newly defining MIMO control information transmission according to the present invention will be described with reference to Table 1 below.

MAP information elements for transmitting MIMO control information shown in Table 1 will be described. First, the first 8 bits of the MAP information element for using MIMO indicates 3 bits of a type field and 5 bits of a sub-type field of the MAP information element. The value of the MAP information element format field has a value of 7 when the method proposed by the present invention is applied, and the subform value has a value of 3 when the method proposed by the present invention is applied. Such a value may be set differently according to the definition, but the present invention will be described by way of example.

In addition, the length field located after the type field and the sub-type field of the information element includes 4 bits. The length field indicates the total length of the MIMO control information data located after the length field in bytes. Also, the MIMO control information element following the length field is a bitmap length field. The bitmap length field is composed of 4 bits and indicates the length of a bitmap located after the bitmap length field in nibble units. Accordingly, the length of the bitmap field located after the bitmap length field is determined by the length indicated by the bitmap length field. After that, each bitmap is included as necessary, and each bitmap determines a space time coding (hereinafter referred to as "STC") method.

Then, the power control method is selected as an open-loop method or a closed-loop method, and a 2-bit matrix indicator for determining how to transmit is determined during transmission. . In addition, if only a few parts of the other parts shown in Table 1 are further examined, the encoding and modulation scheme of each transmitted data is determined by a downlink information usage code (DICU). That is, it is a field that can apply AMC. The padding field is a field for configuring the size of the entire field to be in bytes. That is, it is configured to further include a dummy bit in order to match when it is not a byte unit.

As described above, the message included in the message according to the present invention is divided into three parts. The first part is a bitmap length field indicating the length of the bitmap. The second part is a bitmap that represents the selected burst that is assigned MIMO data. And the last part is the part that delivers the MIMO information list delivered to the burst selected by the bitmap.

In more detail, the length of the bitmap varies according to the value of the bitmap length field, and each bit of the bitmap represents a sequential order in which a burst message is transmitted. That is, each bit corresponds to the order of the burst, and when a value is "1" in the corresponding order, a burst message indicating control information is transmitted. When the value is "0" in the corresponding order, a burst message indicating control information is transmitted. This will be described in more detail with reference to FIG. 3 to be described later.

Then, the following describes the control process for the transmission / reception of the message of the above <Table 1>.

1 is a control flowchart when transmitting a MAP information element for transmitting MIMO control information in a base station according to a preferred embodiment of the present invention. Hereinafter, a control process of transmitting a MAP information element for transmitting MIMO control information according to the present invention will be described in detail with reference to FIG. 1.

In step 100, the base station performs scheduling to select terminals to which the burst message is to be delivered. Such scheduling includes scheduling of forward transmission and reverse transmission. However, in FIG. 1, only scheduling of forward transmission will be described as an example. That is, step 100 is a process in which the base station performs scheduling on all burst messages in which data to be transmitted to the terminal exists. Therefore, when there is a message to be transmitted to the terminal, the priority is determined according to the scheduling result. When the priority of the burst messages to be transmitted to the terminal is determined as described above, the base station determines the burst to be included in the MAP message in step 102. That is, to determine the burst messages to be transmitted at the present time.

The MAP message informs a certain terminal at which point a burst message is delivered in some way. After determining the burst to be included in the MAP message as described above, the base station proceeds to step 104 and checks whether a MIMO burst exists. If the MIMO burst exists in step 104, the procedure proceeds to step 106; otherwise, the routine ends. In FIG. 1 according to the present invention, the routine is described as being terminated. In reality, the process of generating and transmitting a MAP message when the present invention is not applied is performed. However, these processes are not related to the present invention, and since they are general processes for generating a MAP message, the description is omitted here and will not be described.

On the other hand, when the process proceeds from step 104 to step 106, that is, when there is a MIMO burst, the base station corresponds to the corresponding burst for transmitting the MIMO control information as shown in Table 1, respectively. Create them. These MAP control information elements are shown in FIG. 3 to be described later and will be described with reference to FIG. 3. In this process, when a message for transmitting MIMO control information and a general MAP message are generated, the base station broadcasts it to all terminals.

2 is a control flowchart when receiving a MAP information element for transmitting MIMO control information in a base station according to a preferred embodiment of the present invention. Hereinafter, referring to FIG. 2, a control process when receiving a MAP information element for transmitting MIMO control information according to the present invention will be described in detail.

In step 200, the terminal receives a MAP message broadcast by the base station. Thereafter, the terminal determines the burst included in the MAP message in step 202. This will be described in more detail with reference to FIG. 3.

3 is a conceptual diagram illustrating an internal configuration of a MAP message and a burst message transmission according to an exemplary embodiment of the present invention. Referring to FIG. 3, burst messages 312, 313, 314, 315, and 316 are transmitted in a forward transmission interval after the MAP message 311. The MAP message 311 includes information for indicating a terminal to receive such burst messages 312, 313, 314, 315, and 316. That is, the MAP_IEs 322, 323, 324, 325, and 326 located after the MIMO control information MAP_IE 321 are information indicating to which UE and in what manner. That is, the Compact_MAP_IEs described above with reference to FIG. In addition, a bitmap length 331 field is included in the MIMO control information MAP_IE 321 and transmitted. The bitmap length field 331 indicates the length of the bitmap 332 field as described above. In the case where the bitmap length field 332 has a length of 2 nibbles as illustrated in FIG. Bit. As illustrated in FIG. 3, the bitmap is transmitted as "01001000". In the upper part of FIG. 3, a MIMO burst is transmitted to a second part and a fifth part of burst messages 312, 313, 314, 315, and 316 located after the MAP message 311. As such, when two MIMO control information are transmitted, each of the MIMO control information 333 and 334 corresponds to the MAP_IE 323 and 326, respectively. In addition, the BITMAP length field 331 related to MIMO in the bitmap only needs to represent an area to which a burst related to MIMO is transmitted. For example, if 20 bursts are transmitted, and up to 5th MAP_IE is a bus related to MIMO, MIMO can be represented up to 8th position using only 8 bits of 2 nibbles. It is only necessary to express up to an area capable of transmitting bursts related to MIMO, and there is no need to express information thereafter. That is, five nibbles are required to actually express all 20 bursts, but according to the present invention, two nibbles can be represented. That is, the amount of information transmitted can be reduced.

Next, a process of transmitting a MAP information element for transmitting MIMO control information according to the present invention transmitted by such a transmission method will be described again with reference to FIG. 2. As described above, when the terminal receives the MAP message in step 200, the terminal examines the MAP message in step 202 to determine which bursts are indicated by the MAP message. This determination will be described with an example of checking whether the MIMO control information is transmitted in the embodiment of FIG. 2 illustrating the present invention. Other cases are not illustrated in FIG. 2, and other cases will not be described.

After determining the burst in step 202, the terminal proceeds to step 204 to check whether the terminal is a terminal capable of MIMO function. If it is determined that the MIMO function is available to the UE, the process proceeds to step 206. Otherwise, the routine is terminated. In reality, however, if it is not the MIMO terminal, it checks whether a burst is transmitted to itself, and further performs the operation accordingly. This section is not described here.

In step 204, if the terminal is a terminal capable of MIMO function, the terminal proceeds to step 206 to examine the bitmap length field and the bitmap field as shown in FIG. Determine the order of bursts assigned to In step 208, the terminal receives MIMO control information in burst order, and receives burst data according to the order. Then, decoding of the received data is performed. This process enables processing of burst messages.

As described above, in the present invention, the base station can efficiently transmit MIMO control information to the terminal to support the MIMO function in the broadband wireless access system, and the MAP information element and its generation and processing can be made smoothly. Therefore, by using the MAP information element of the present invention, there is an advantage in that an efficient MAP message for allocating frequency bands, coding and modulation schemes, etc. for each terminal can be constructed.

1 is a control flowchart of transmission of a MAP information element for transmission of MIMO control information in a base station according to an embodiment of the present invention;

2 is a control flowchart when receiving a MAP information element for transmitting MIMO control information in a base station according to an embodiment of the present invention;

3 is a conceptual diagram illustrating an internal configuration of a MAP message and a burst message transmission according to an exemplary embodiment of the present invention.

Claims (2)

A method for transmitting control information of a multiple input multiple output in a broadband wireless access system comprising a base station capable of transmitting a burst message using a multiple input multiple output (MIMO) scheme with a wireless terminal, When a burst message to be transmitted to the terminals is generated, scheduling the burst messages and determining a burst message to be included in a MAP message according to a scheduling result; And constructing and transmitting a map information element for transmitting the control information of the multi-input multi-output method when the burst message of the multi-input multi-output method exists in the burst message to be included in the map message. Way. In a broadband wireless access system including a wireless terminal and a base station capable of transmitting a burst message by using a multiple input multiple output (MIMO) scheme with a wireless terminal for receiving the control information of the multiple input multiple output when transmitted. In the method, Receiving a MAP message from the base station, examining burst messages included in the map message, and checking whether the multi-input multiple-output control information map information element is present in the burst message; When the multi-input multi-output control information map information element exists, a burst message is received by the multi-input multi-output control information and the multi-input multi-output function when the terminal can perform a multi-input multi-output function. To examine the process, And receiving a burst message according to the checked result and decoding the burst message according to the multi-input multi-output control information.