KR20060017091A - Method and system for fragmenting uplink/downlink channel message in broadband wireless access system - Google Patents

Abstract

The present invention provides a wireless broadband Internet service to a terminal, and in a broadband wireless access system that shares a common channel, the base station is transmitted to the terminal so that each user uses a separate channel for each user every frame. A method of dividing a downlink channel information message, the method comprising: searching whether there is characteristic information on the uplink / downlink channel to be transmitted to the terminal; and the amount of information on the found uplink / downlink channel exceeds a preset frame size If the amount of information on the found uplink / downlink channel exceeds the frame size, dividing the uplink / downlink channel information message including information of the neighbor base stations; By setting a field related to an uplink / downlink channel information message, And transmitting a downlink / downlink channel information message at a predetermined period.

Broadband wireless access system, uplink / downlink channel information (UCD. DCD) message segmentation, fragmentation, TLV.

Description

Method and system for segmenting uplink / downlink channel information message in broadband wireless access system             

1 is a diagram illustrating a set of adjacent base stations divided by a current divided message number and a total number of divided messages according to a preferred embodiment of the present invention;

2 is a diagram illustrating uplink / downlink channel information message division in a broadband wireless access system according to an embodiment of the present invention;

3 is a flowchart illustrating a split operation of an uplink / downlink channel information message according to a preferred embodiment of the present invention.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a broadband wireless access system, and more particularly, to a broadcast message segmentation method and system for informing neighboring base station information to a mobile station in a mobile broadband wireless access system.                         

In general, communication systems have been developed mainly for voice services, and are gradually developing as communication systems capable of not only voice but also data services and various multimedia services. However, since the voice-oriented communication system has a relatively small data transmission bandwidth and a high usage fee, the voice-oriented communication system cannot meet the rapidly increasing demand for users. In addition, due to the development of the communication industry and increasing user demand for Internet services, there is an increasing need for a communication system that can efficiently provide Internet services. As a result, broadband wireless access systems have been introduced to efficiently provide Internet services with broadband enough to meet the increasing demands of users.

The broadband wireless access system is a system for integrating and supporting not only voice but also various low speed and high speed data services and multimedia application services such as high definition video. The broadband wireless access system can access PSTN and PSDN networks, Internet networks, IMT-2000 networks, ATM networks, etc. in a mobile or fixed environment based on wireless media using broadband such as 2 GHz, 5 GHz, 26 GHz and 60 GHz. It is a wireless communication system that can support more than a channel rate. The broadband wireless access system may be classified into a broadband wireless subscriber network, a broadband mobile access network, and a high-speed wireless LAN according to the mobility (fixed or mobile) and communication environment (indoor or outdoor) of a terminal, and a channel rate.

The wireless access method of the broadband wireless access system is being standardized by the IEEE 802.16 standardization group of the Institute of Electrical and Electronics Engineers, one of the international standardization organizations, and currently provides wireless broadband Internet service to fixed terminals. The IEEE 802.16d standard is being promoted as a standard for this purpose.

The IEEE 802.16d standard has a wider bandwidth of data than a conventional wireless technology for voice service, so that a large amount of data can be transmitted in a short time, and all user channels can be shared to efficiently use the channel. Do. In addition, quality of service (QoS) is guaranteed so that users can receive different quality of services according to the characteristics of the service. In the IEEE 802.16d system, all users connected to a base station share a common channel, and each user uses a channel, and an interval for each user is allocated by the base station every uplink and downlink frame. Uplink and downlink access information should be informed so that it can be used separately.

In the IEEE 802.16d system, channel information is divided into an uplink channel and a downlink channel, and information about each channel is defined as a TLV (Type, Length, Value) and included in a downlink channel descriptor (DCD) and an uplink channel descriptor (UCD) message. By transmitting the information to all the users to inform the terminal of the characteristic information on the channel.

However, in IEEE 802.16d / D5, there is a problem in that the MAC management message cannot be transmitted by being fragmented. In addition, when the channel information to be broadcast is increased, the size of the channel information message is increased so that not all the information is contained in one frame, so there is a problem in that the channel information cannot be broadcast to the terminal.

 Accordingly, an object of the present invention is to provide a method and system for dividing an uplink / downlink channel information message to be transmitted to a terminal in a broadband wireless access system.

Another object of the present invention is to provide a method and system for dividing by adding a specific value to an uplink / downlink channel information (UCD / DCD) message to be transmitted to a user equipment in a broadband wireless access system.

The method for achieving the object of the present invention, in the broadband wireless access system to provide a wireless broadband Internet service to the terminal, and share a common channel, the base station is used by each user each channel divided by each user A method of dividing an uplink / downlink channel information message transmitted to the terminal, the method comprising: searching for whether there is characteristic information about the uplink / downlink channel to be transmitted to the terminal; and amount of information about the found uplink / downlink channel. Checking whether the frame size exceeds the preset frame size, and when the amount of information on the found uplink / downlink channel exceeds the frame size, dividing the uplink / downlink channel information message including information of the neighbor base stations; And fields related to the split uplink / downlink channel information message. And transmitting the set up / down channel information message to the terminal at predetermined intervals.

The system for achieving the objects of the present invention is to provide a wireless broadband Internet service to a terminal, and in a broadband wireless access system sharing a common channel, the base station is divided by each user channel every user A system for dividing an uplink / downlink channel information message transmitted to the terminal for use, wherein the amount of information about the uplink / downlink channel to be transmitted to the terminal exceeds the frame size, and includes information of the neighbor base stations. The base station for dividing the uplink / downlink channel information message and setting a related field, and then transmitting the set uplink / downlink channel information message to the terminal at a predetermined period; and the uplink / downlink channel information at a predetermined period from the base station. Receive a message, the received broadcast message Check the fields associated with the information of the neighbor base stations included in characterized in that it comprises the user terminal to determine whether or not the divided message.

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, 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 is applied to an IEEE 802.16d system to which mobility is added, and according to an embodiment of the present invention, an uplink / downlink channel information message including channel information having a large size is informed by the IEEE 802.16d. The transmission method and system will be described.

In general, a broadband wireless access system includes a terminal 10 and a plurality of base stations 20a, 20b, ..., 20g. The terminal 10 transmits / receives a downlink / uplink channel information message with the base station 20a currently receiving a service.                     

In a broadband wireless access system having such a structure, an uplink / downlink channel information message will be described with reference to Tables 1 and 2 below.

First, referring to the uplink channel information message, 1 byte of TLV information is additionally allocated to an uplink channel information (UCD) message for splitting and transmitting uplink channel information. Channel encoding of the downlink channel information is shown in Table 1 below.

The uplink channel information (DCD) message generally adds a "Fragmentation" field as shown in Table 1 for segmented transmission of known channel information. Here, the 6-bit "Fragmentation" field includes Type and Length of 1 bit.

The lower 4 bits of the 8-bit value of "Fragmentation" means the total number of divided messages, and the upper 4 bits mean the number of currently divided messages. That is, if the UCD message is divided into two, the "Fragmentation" of the first message has a binary value 00010010, and the "Fragmentation" of the second message has a binary value 00100010.

Next, referring to the downlink channel information message, the channel encoding scheme of the DCD message for splitting downlink channel information is shown in Table 2 below. The DCD channel encoding scheme is the same as the UCD channel encoding scheme.                     

 The uplink channel information (DCD) message generally adds a "Fragmentation" field as shown in Table 1 for the divided transmission of known channel information. Here, the 18-bit "Fragmentation" field includes type and length information of 1 bit.

It is the same as the UCD channel encoding scheme. That is, the lower 4 bits of the 8-bit value of "Fragmentation" means the total number of divided messages, and the upper 4 bits mean the number of currently divided messages. If the UCD message is divided into two, "Fragmentation" of the first message has a binary value 00010010, and "Fragmentation" of the second message has a binary value 00100010.

As described above, the UCD / DCD message is divided into 4 bits of current fragment index information (Current Fragmentation Index) information and 4 bits of total fragment information (Total Fragmentation) information. This newly added information is as shown in FIG. 2.

A method of dividing the newly defined UCD / DCD message will be described with reference to the accompanying drawings.

3 is a diagram illustrating UCD / DCD message partitioning in a broadband wireless access system according to a preferred embodiment of the present invention.                     

Referring to FIG. 3, if the amount of uplink / downlink channel information UCD / DCD increases, the block 310 exceeds one frame of a predetermined size. Due to the difficulty in transmitting such a message, the message is divided according to the frame size by adding a TLV called "Fragmentation" to each of the UCD / DCD messages. That is, the block 320 is divided into a block 330. The UCD / DCD message is formed of a message type (Type), message identifier (ID), message count information (Count), TLV, and burst profile (Burst_Profile) 1-20.

Block 320 includes a message identification number (ID) and message count information identical to the message type included in block 310, wherein the " Fragmentation " TLV is included in one area. Some of the burst profile information of the block 320 includes burst profile information 1 to 12.

 Block 330 includes the same message identification number (ID) and message count information as the message type (block 320), the current partition index and the total number of partitions and the remaining burst profile information (13 to 20) ).

The base station includes the total number of messages to be split according to the frame size to be transmitted in "Total Fragmentation", includes the current fragment index in the "Current Fragmentation Index", and then adds uplink / downlink channel information (UCD / DCD). Split and send Accordingly, the uplink / downlink channel information message can be divided into several frames and transmitted several times.

A splitting operation of a broadcast message including such neighbor base station information will be described with reference to the accompanying drawings.

4 is a flowchart illustrating a partitioning operation of an uplink / downlink channel information message according to a preferred embodiment of the present invention.

Referring to FIG. 4, in step 401, the base station determines whether there is channel information indicating characteristics of an uplink / downlink channel to be transmitted to the terminal. In this case, if there is uplink / downlink channel information, in step 403, the base station determines whether the amount of the channel information is larger than a preset frame size. In this case, when the amount of the channel information is not greater than the frame size, in step 409, the base station includes the channel information in the uplink / downlink channel information message and transmits the same to the terminal.

Otherwise, in step 405, the base station divides the uplink / downlink channel information message including the channel information into a size within a frame size.

Then, in step 407, the base station sets the newly added "Fragmentation" field to the corresponding value. That is, if a message including neighboring base station information is split into two, for example, if the UCD message is split into two as described above, the "Fragmentation" of the first message has a binary value 00010010, and the " Fragmentation "has a binary value 00100010. Then, in step 409, the base station transmits the set up / down channel information message to the terminal at a predetermined cycle.

The UE receiving the UCD / DCD message checks the “Fragmentation” field to determine whether the message is split. That is, if there is no field defined in "Fragmentation", it means that the received message is not split. If the field value exists, the total number of split messages is checked to wait for the next split message to be received.

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 defined not only by the scope of the following claims, but also by the equivalents of the claims.

As described above, the present invention divides the message according to the frame size by adding a TLV called fragmentation to the uplink / downlink channel information message in the wideband wireless access system so that even channel information of a large size is divided into several frames and transmitted. There is an effect that can inform the terminal of the characteristic information on the channel without loss.

Claims (4)

In a broadband wireless access system that provides a wireless broadband Internet service to a terminal and shares a common channel, the base station transmits an uplink / downlink channel information message to the terminal for each user to use a separate channel for each user. In the method for dividing, Searching whether there is characteristic information on the uplink / downlink channel to be transmitted to the terminal; Checking whether an amount of information on the found uplink / downlink channel exceeds a preset frame size; Dividing the uplink / downlink channel information message including information of the neighbor base stations when the amount of information on the found uplink / downlink channel exceeds the frame size; And setting a field related to the divided uplink / downlink channel information message and transmitting the set uplink / downlink channel information message to the terminal at a predetermined period. The method of claim 1, The uplink / downlink channel information further includes a partition information field, wherein the partition information field is divided into index information of a currently partitioned message and information on the total number of partitioned messages. In a broadband wireless access system that provides a wireless broadband Internet service to a terminal and shares a common channel, the base station transmits an uplink / downlink channel information message to the terminal for each user to use a separate channel for each user. In the system for dividing When the amount of information about the uplink / downlink channel to be transmitted to the terminal exceeds the frame size, the uplink / downlink channel information message including the information of the neighbor base stations is divided and the related field is set to the terminal. The base station for transmitting the set up / down channel information message at a predetermined period; And receiving the uplink / downlink channel information message from the base station at a predetermined period, and confirming whether a message is divided by checking a field related to information of the neighboring base stations included in the received broadcast message. The system described above. The method of claim 1, The uplink / downlink channel information further includes a partition information field, wherein the partition information field is divided into index information of a currently partitioned message and information on the number of total partitioned messages.

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