KR100816441B1 - Method and System for Allocating Adaptive Modulation and Coding Subchannel for Use in Portable Internet Network - Google Patents

Abstract

The present invention relates to a method and a system for distributing radio resources between selected bands of an AMC subchannel when a mobile communication terminal requires the use of an AMC subchannel interval in a portable Internet network.

In a system for allocating an AMC subchannel in a portable Internet network using a personal subscriber station that transmits an SINR value, the portable Internet service is used by accessing the portable Internet network using an orthogonal frequency division multiple access (OFDMA) method. Personal subscriber station; A radio access station that is an access point (AP) of a portable Internet system; An access control router controlling a plurality of radio access stations; A home agent for routing packets from an external packet data service server including the Internet; A data service server for transmitting data of various contents in the form of a packet; A network management system (NMS) server for establishing a central monitoring system of devices on a network to monitor, plan and analyze, and to store related data and make it available on demand; An authentication server for authenticating a connection from a personal subscriber station; And an IP network connecting an access control router, a home agent, an authentication server, and an NMS server, to provide an AMC subchannel allocation system in a portable Internet network using a personal subscriber station transmitting SINR values.

According to the present invention, in the case of a portable Internet system using AMC, the fairness between users cannot be guaranteed because the data rate varies depending on the channel state according to the location of the user, but the number of OFDM symbols for the AMC subchannel interval is determined through resource redistribution. By reducing the number of users of the diversity subchannels, the occupied data volume for each band is similarly distributed, thus enabling efficient resource use, thereby increasing the overall yield of the system.

AMC Subchannel, Mobile Internet

Description

Method and System for Allocating Adaptive Modulation and Coding Subchannel for Use in Portable Internet Network

1 is a block diagram showing an OFDMA frame structure of a portable Internet system according to an embodiment of the present invention;

 2 is a schematic view showing a portable internet system according to a preferred embodiment of the present invention;

3 is a diagram schematically showing a configuration of a radio access station according to a preferred embodiment of the present invention;

4 is a flowchart illustrating an AMC subchannel allocation method in a portable Internet network according to a preferred embodiment of the present invention.

<Description of Symbols for Main Parts of Drawings>

100: assignable band 110: downlink

112: preamble 120: uplink

130: PUSC subchannel 140: diversity subchannel

142: Tile 150: AMC Subchannel

152: empty 160: TTG

170: RTG 200: personal subscriber station

210: radio access station 220: access control router

230: home agent 240: authentication server

250: IP network 260: Internet

270: Data Service Server 280: NMS Server

310: scheduler 320: resource allocation

330: OFDM transmission unit

The present invention relates to an adaptive modulation and coding (AMC) subchannel allocation method and system in a portable Internet network. More specifically, in a radio access station that allocates a channel for transmitting and receiving data to and from a personal subscriber station, an orthogonal frequency division multiplex (OFDM) symbol number required for each band is calculated, and the calculated OFDM symbol and the actual personal subscriber station are calculated. AMC subchannel allocation in a mobile Internet network using a personal subscriber station generating a list of target user sets to redistribute AMC subchannels compared to the number of symbols provided and transmitting SINR values for efficient AMC subchannel redistribution to the personal subscriber station The present invention relates to an AMC subchannel allocation system in a portable Internet network using a personal subscriber station transmitting a SINR value.

As computers, electronics, and communication technologies have advanced dramatically, various wireless communication services using wireless networks have been provided. The most basic wireless communication service is a wireless voice call service that provides a voice call to a mobile terminal user wirelessly, which can provide a service regardless of time and place. In addition, while providing a text message service to complement the voice call service, a wireless Internet service has recently emerged to provide an Internet communication service to a user of a mobile communication terminal through a wireless communication network.

As a result of the development of mobile communication technology, the services provided by the Code Division Multiple Access (CDMA) mobile communication system are not only voice services, but also developed into a multimedia communication service that transmits data such as circuit data and packet data. I'm going.

In addition, recently, with the development of information and communication, IMT-2000 (International Mobile Telecommunication 2000), a third generation mobile communication system that has been standardized by the International Telecommunication Union-Radio (ITU-R) (for example, CDMA2000 1X, 3X, EV) -DO, WCDMA (WideBand CDMA, etc.) are commercially available. IMT-2000 is CDMA 2000 1X, 3X, EV-DO, WCDMA (WideBand CDMA), etc .. It is a service that can provide wireless Internet at a transmission speed of up to 144 Kbps, much faster than the supportable data transfer rate of 14.4 Kbps or 56 Kbps. In particular, by using IMT-2000 service, it is possible to provide various multimedia services (AOD, VOD, etc.) at higher speed as well as improving existing voice and WAP service quality.

However, the existing mobile communication system has a limitation in providing high-speed wireless Internet due to high base station construction cost and high usage rate of the wireless Internet, and a limited screen size of the mobile communication terminal.

In addition, wireless local area network (WLAN) technology has limitations in providing public services due to problems such as radio wave interference and a narrow coverage area. Therefore, a high-speed portable Internet (HPi: High-Speed Portable internet or WiBro: Wireless Broadband) system has emerged, which guarantees portability and mobility and can use a high-speed wireless Internet service at a low price.

The mobile internet is located between the wireless LAN and the mobile communication-based wireless internet, and is a service that combines the advantages of both. Refers to a service that can obtain or utilize information and content. In other words, the portable Internet has a lower transmission speed than a wireless LAN having an advantage in terms of transmission speed, but it guarantees mobility of the terminal and does not support high-speed mobility of a mobile communication-based wireless Internet having advantages in terms of mobility. It is an IP (Internet Protocol) based wireless data system having up-down asymmetric transmission characteristics capable of providing Internet services.

The portable Internet requires a link adaptation technique in order to secure an appropriate signal-to-interference ratio (C / I) according to the position of the terminal, and a representative method is power control. However, due to the limitation of the maximum transmission power, the coverage is limited to a certain degree because all users in the cell want to secure the same data rate and quality through power control only. In the case of a terminal farther than a terminal close to the base station, higher power may be allocated to secure the same quality. In particular, in the case of uplink, increasing power at the cell boundary causes co-channel interference to adjacent cells using the same frequency. Therefore, power control should be performed to allocate the minimum power required for quality assurance.

The link adaptation technique, which is used instead of the power control in the portable Internet, is a method of adaptively controlling the transmission rate according to the channel state. In general, the correlation function value of the received signal size decreases as the speed of the terminal increases, whereas when the terminal speed is low, the value increases relatively. For example, if the Doppler frequency can be maintained within 0.8 over 20 ms when the Doppler frequency is 5 Hz, the channel state does not change over multiple frames. Therefore, an appropriate level of modulation and channel coding can be adaptively applied according to a given channel state, and this is called adaptive modulation and coding (AMC).

On the other hand, in a packet data system such as a mobile Internet, the throughput of the entire system can be maximized by scheduling the transmission so that a user having a good channel state can transmit first. In general, the method of allocating resources based on the channel state allocates resources sequentially according to the user priority determined by the scheduler. In other words, if the resources with the highest priority are allocated to the user most suitable for the user and resources to be allocated remain, the bands are allocated to the user having the next priority in order. Since the channel state of each user is theoretically independent of each other, the bands required by each user are distributed evenly among the 24 bands, but there are specific bands commonly required by multiple users. If the low-priority user's required band is such a specific band, the low-priority user can't be allocated an appropriate band because the band is preempted by the high-priority user. Could not.

Therefore, the AMC scheme generally operates in combination with such scheduling, but a scheduling technique for maximizing the yield of the system and fairness between users is required.

In order to solve this problem, the present invention calculates the number of OFDM symbols required for each band in a radio access station that allocates a channel for transmitting and receiving data to and from a personal subscriber station, and provides the calculated number of OFDM symbols and the actual personal subscriber station. AMC subchannel allocation method and SINR in a portable Internet network using a personal subscriber station generating a list of user sets for AMC subchannel redistribution by comparing the number of symbols and transmitting an SINR value for efficiently distributing an AMC subchannel to a personal subscriber station An object of the present invention is to provide an AMC subchannel allocation system in a portable Internet network using a personal subscriber station transmitting a value.

Accordingly, according to a first object of the present invention, in a system for allocating AMC subchannels in a portable Internet network using a personal subscriber station transmitting a SINR value, orthogonal frequency division multiple access (OFDMA) A personal subscriber station accessing the portable internet network to use the portable internet service; A radio access station that is an access point (AP) of a portable Internet system; An access control router controlling a plurality of radio access stations; A home agent for routing packets from an external packet data service server including the Internet; A data service server for transmitting data of various contents in the form of a packet; A network management system (NMS) server for establishing a central monitoring system of devices on a network to monitor, plan and analyze, and to store related data and make it available on demand; An authentication server for authenticating a connection from a personal subscriber station; And an IP network connecting an access control router, a home agent, an authentication server, and an NMS server, to provide an AMC subchannel allocation system in a portable Internet network using a personal subscriber station transmitting SINR values.

According to a second aspect of the present invention, there is provided a radio access station for allocating an AMC subchannel in a portable Internet network using a personal subscriber station transmitting a SINR value, the radio access station comprising: a scheduler for determining a resource allocation order of the personal subscriber station; A resource allocator configured to map the resource allocation order to the allocation band based on the resource allocation order determined by the scheduler; And an OFDM transmitter configured to generate an OFDM symbol signal and transmit the generated OFDM symbol signal to an access control router or a personal subscriber station, and to allocate an AMC subchannel in a portable Internet network using a personal subscriber station transmitting an SINR value. Provide a station.

를 계산하는 단계; (d) 라디오 액세스 스테이션이 계산된

을 이용하여 각 대역당 요구되는 총 OF DM 심벌 수인

을 계산하는 단계; (e) 라디오 액세스 스테이션에서

이 가장 큰 대역의 OFMD 심벌 수를

로 정의하는 단계; (f) 라디오 액세스 스테이션에서

가 실제 AMC 부채널로 사용할 수 있는 OFDM 심벌 수인

보다 큰 지 여부를 판단하는 단계; (g) 라디오 액세스 스테이션에서

가

보다 작은 경우, 모든 개인 가입자 단말기에 원하는 대역을 할당하는 단계; (h) 라디오 액세스 스테이션에서

가

보다 크다고 판단된 경우, 라디오 액세스 스테이션은 복수의 개인 가입자 단말기가 요청하는 대역이 겹치는 충돌 대역이 존재하는지 판단하는 단계; (i) 복수의 개인 가입자 단말기가 요청하는 대역이 겹치는 충돌 대역이 존재하지 않는 경우, AMC 부채널 사용을 해제하고 제공된 OFDM 심벌 내에서 모든 개인 가입자 단말기에 원하는 대역을 할당하는 단계; (j) 복수의 개인 가입자 단말기가 요청하는 대역이 겹치는 충돌 대역이 존재하는 경우, 라디오 액세스 스테이션은 충돌 대역 중

가 큰 순서대로 충돌 대역을 정렬하고, 이때

의 최대값인 대역을 k'로 정의하는 단계; (k) 라디오 액세스 스테이션은 개인 가입자 단말기 하나하나를 개인 가입자 단말기 h 라고 할 때, 개인 가입자 단말기 h가 k' 대역을 할당받을 경우 얻어지는 개인 가입자 단말기 h의 대역별 할당 심벌 수

와

을 이용한 각 대역당 요구되는 총 OFDM 심벌 수인

를 계산하여 개인 가입자 단말기 h의 집합 A를 설정하는 단계; (l) 집합 A가 설정되면, 라디오 액세스 스테이션에서 각각의 개인 가입자 단말기 h로 대역 k'의 자원을 재분배하고 개인 가입자 단말기 h 각각의

,

및

를 계산하는 단계; (m) 라디오 액세스 스테이션에서

,

및

의 계산이 종료되면

를 최소로 하는 개인 가입자 단말기 h를 선택하여 AMC 부채널을 분배하는 단계; (n) 라디오 액세스 스테이션에서 개인 가입자 단말기 h로 AMC 부채널 분배가 종료되면 충돌 대역 목록을 업데이트하는 단계; 및 (o) 라디오 액세스 스테이션에서 충돌 대역 목록의 업데이트가 종료된 후, 라디오 액세스 스테이션에서는

가 실제 AMC 부채널로 사용할 수 있는 OFDM 심벌 수인

보다 큰 지 여부를 판단하는 단계를 포함하는 것을 특징으로 하는 SINR 값을 전송하는 개인 가입자 단말기를 이용한 휴대 인터넷망에서 AMC 부채널 할당 방법을 제공한다.According to a third object of the present invention, there is provided a method for allocating an AMC subchannel in a portable Internet network using a personal subscriber station transmitting a SINR value, the method comprising: (a) a radio access station for providing data communication to a personal subscriber station; Assigning a band, and the personal subscriber station calculating a SINR value of the allocated band; (b) if the SINR value of the band selected by the personal subscriber station is calculated, transmitting the SINR value to the radio access station; (c) based on the SINR value transmitted by the personal subscriber station,

Calculating; (d) the radio access station is

Is the total number of OF DM symbols required for each band

Calculating; (e) at a radio access station

The number of OFMD symbols in this largest band

Defining as; (f) at the radio access station

Is the number of OFDM symbols available for the actual AMC subchannel

Determining whether greater than; (g) at the radio access station

end

If smaller, allocating a desired band to all personal subscriber stations; (h) at the radio access station

end

If determined to be greater, the radio access station determining whether there is a collision band in which bands requested by the plurality of personal subscriber stations overlap; (i) if there is no collision band overlapping bands requested by a plurality of personal subscriber stations, canceling use of the AMC subchannel and allocating a desired band to all personal subscriber stations within the provided OFDM symbol; (j) If there is a collision band in which bands requested by a plurality of personal subscriber stations overlap, the radio access station is in the collision band.

Sorts the collision bands in ascending order, where

Defining a band that is the maximum value of k '; (k) When the radio access station refers to each individual subscriber station h as a personal subscriber station h, the number of allocation symbols per band of the personal subscriber station h obtained when the personal subscriber station h is allocated the k 'band.

Wow

Is the total number of OFDM symbols required for each band

Calculating a and setting a set A of individual subscriber stations h; (l) Once set A is established, the radio access station redistributes the resources of band k 'to each individual subscriber station h and

,

And

Calculating; (m) at the radio access station

,

And

When the calculation of ends

Distributing the AMC subchannels by selecting the personal subscriber station h with the minimum number; (n) updating the collision band list when the AMC subchannel distribution is terminated from the radio access station to the personal subscriber station h; And (o) after updating of the collision band list at the radio access station is finished,

Is the number of OFDM symbols available for the actual AMC subchannel

The present invention provides an AMC subchannel allocation method in a portable Internet network using a personal subscriber station transmitting a SINR value.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First of all, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are used as much as possible even if displayed on different drawings. In addition, in describing the present invention, when it is determined that the detailed description of the related well-known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

1 is a block diagram showing an OFDMA frame structure of a portable Internet system according to a preferred embodiment of the present invention.

Slots in the portable Internet standard are designated in two-dimensional space according to the number of symbols and the number of subcarriers in the time and frequency domain, respectively, and the symbols become the minimum unit of allocation.

Slots depend on how subchannels are actually configured on the uplink 120 and downlink 110. In the mobile Internet, subcarrier allocation is a diversity subchannel by grouping subcarriers scattered by permutation. And a method of configuring 140 and a method of configuring AMC (Adaptive Modulation and Coding) subchannel 150 by tying physically contiguous subcarriers for each band.

The first symbol of the downlink 110 is assigned a preamble 112, and the preamble is used for frame synchronization and cell division.

A TTG (Transmit / recieve Transition Gap) 160 is inserted between the downlink 110 and the uplink 120, and a Receive / transmit Transition Gap (RTG) 170 is inserted between the end of the frame and the start of the frame, thereby providing a maximum coverage of 1 km. To accept.

The 5 ms long frame consists of 42 OFDM symbols, TTG 160 and RTG 170.

Downlink 110 transmission begins with one preamble symbol, a frame control header (FCH), a DL-MAP, and a data symbol.

The two symbols immediately following the preamble 112 are always used as the Partial Usage SubChannel (PUSC) subchannel 130 and include a 24-bit FCH for transmitting frame configuration information.

PUSC is a concept of allocating different subchannels by sector by dividing the subchannels without using all the subchannels in one sector. This is contrary to the Full Usage SubChannel (FUSC), which uses all subchannels in a sector. .

In the case of the uplink 120, the first three symbols are used to transmit control information such as ranging and channel quality indicators.

There are three types of subchannels in the downlink frame: PUSC subchannel 130, diversity subchannel 140, and AMC subchannel 150.

There are two types of subchannels in the uplink frame: diversity subchannel 140 and AMC subchannel 150.

The diversity subchannel 140 scatters the entire band to form a subcarrier and changes its permutation in symbol units, thereby obtaining a diversity effect in the frequency domain.

For diversity subchannel 140, one slot in downlink 110 consists of one subchannel and one OFDMA symbol and one slot in uplink 120 includes one subchannel and three OFDMA It consists of a symbol.

Since the AMC subchannel 150 is configured by concatenating consecutive subcarriers for each band, it is possible to maximize bandwidth efficiency by selecting and allocating a band having a good channel state.

In the case of the AMC subchannel 150, one slot in the downlink 110 and the uplink 120 are configured with one subchannel and one OFDMA symbol.

The subchannels of the downlink 110 and the uplink 120 have separate transmission intervals consisting of consecutive symbols, and the PUSC subchannel 130 of the downlink 110 is defined over two symbols, one The PUSC subchannel 130 is composed of four pilot subcarriers and 48 data subcarriers.

The diversity subchannel 140 of the downlink 110 is composed of 48 subcarriers selected from valid subcarriers available in one symbol.

The basic allocation unit constituting the diversity subchannel 140 of the uplink 120 is a tile 142 formed by collecting three adjacent subcarriers in three consecutive symbol intervals, or in three consecutive symbol intervals. A tile (including four pilot subcarriers) 142 formed by collecting four adjacent subcarriers may be used.

The diversity subchannel 140 of the uplink 120 consists of six tiles 142, each tile 142 being distributed over the entire frequency band.

The basic unit constituting the AMC subchannel 150 of the downlink 110 and the uplink 120 is a bin 152, and the bin 152 is composed of nine adjacent subcarriers in the same symbol. The AMC subchannel section of the link 110 and uplink 120 is composed of a plurality of bands and there are four bins 152 in one band.

The AMC subchannel 150 of the downlink 110 and uplink 120 is comprised of six adjacent bins 152 present in the same band. Here, the position of the pilot subcarrier is determined according to the position of the bin 152 and the position of the symbol.

After the RTG 170, the subchannel in the first symbol after the preamble 112 of each frame is allocated an FCH, and is a region for transmitting a downlink frame prefix (DL_Frame_Prefix), and the downlink frame prefix is a DL-MAP that follows later. Information related to the current frame is transmitted, including the length of the message, the repetitive coding and the channel coding scheme applied to the DL-MAP.

The downlink frame prefix consists of all 24 bits, which are repeated in a 48-bit FEC block, transmitted through QPSK modulation, R = 1/2 encoding, and sent four times.

2 is a schematic diagram of a portable Internet system according to a preferred embodiment of the present invention.

In the portable Internet network according to the present invention, the AMC subchannel allocation system includes a personal subscriber station (PSS) 200, a radio access station (RAS) 210, and an access control router (ACR). Router (220), Home Agent (HA) 230, Authentication Server (AAA: Authentication, Authorization And Accounting) 240, IP Network 250, Internet 260, Data Service Server 270 And NMS (Network Management System) servers.

The personal subscriber station 200 refers to a mobile communication terminal that uses a portable Internet service by accessing a portable Internet network using an Orthogonal Frequency Division Multiple Access (OFDMA), and uses a low power RF (IF) / IF (Intermediate). Equipped with Frequency (Module) module, it has MAC (Media Access Control) frame variable control function, handoff function, multicast service reception function, interworking with other network, user authentication and encryption function according to service characteristics and propagation environment. It is a device that selects a band to transmit and receive data through a portable Internet network, and measures the signal to interference and noise ratio (SINR) of the selected band and transmits it to a radio access station. .

The radio access station 210 wirelessly transmits or receives data received from the access control router 220 to or from the personal subscriber station 200 as an access point (AP) of a portable Internet system. It acts as a data repeater that transmits one data to the access control router 220, and manages and controls radio resources, handoff support function, downlink multicast function, billing, statistical information generation and notification function, authentication and security function. It has a device that receives the SINR value transmitted by the personal subscriber station 200.

The access control router 220 accommodates a plurality of radio access stations 210 to control handoffs between the radio access stations 210, IP routing and handoff management functions, provide billing services to billing servers, and IP multicast functions. It is a device that provides resource management and control functions, authentication and security functions.

The home agent 230 performs routing for transmitting a packet from an external packet data service server including the Internet 260, and the authentication server 240 works in conjunction with the radio access station 210 to provide a personal subscriber station ( Charge the packet data used in 200, and authenticates the connection from the personal subscriber station (200).

The IP network 250 connects the access control router 220, the home agent 230, the authentication server 240, the NMS server 270, the downlink / uplink ratio setting server 280, and the like. The packet data is received from an external packet data service server including the Internet 260 and a data service server providing various contents, and transmitted to the access control router 220.

The NMS server 280 establishes a central monitoring system of the devices on the network to perform monitoring, planning, and analysis, and stores related data so that they can be immediately used as needed.

3 is a diagram schematically illustrating a configuration of a radio access station for allocating an AMC subchannel in a portable Internet network using a personal subscriber station transmitting an SINR value according to a preferred embodiment of the present invention.

First, the scheduler 310 determines the resource allocation order of the personal subscriber station 200 using the SINR value and the coded packet size information transmitted from the personal subscriber station 200 and performs OFDM on the packet data transmitted from the personal subscriber station 200. It is a device for transmitting to the transmitter 330.

The resource allocator 320 receives the resource allocation order from the scheduler 310 and maps the resource allocation order transmitted from the scheduler 310 to a predetermined band so that each individual subscriber station 200 may be sequentially allocated resources. (Mapping) is a device for transmitting to the OFDM transmitter 330.

When the band information to which the resource allocation order is mapped is transmitted from the resource allocator 320, the OFDM transmitter 350 sorts the packet data transmitted through the scheduler 310 in the order of band mapping and generates an OFDM symbol signal. To the access control router 220 or the personal subscriber station 200.

4 is a flowchart illustrating a method for allocating an AMC subchannel in a portable Internet network using a personal subscriber station transmitting an SINR value according to an embodiment of the present invention.

First, when the radio access station 210 allocates a band to provide data communication to the personal subscriber station 200, the personal subscriber station 200 is suitable for the band environment among the bands allocated by each radio access station 210. 4 to 5 bands are selected and SINR values of the selected bands are calculated at step S400.

When the calculation of the SINR value is completed in the personal subscriber station 200 and the SINR value of the selected band is calculated, the calculated SINR value is transmitted to the radio access station 210 (S402).

와 제 i 개인 가입자 단말기(202)가 선택한 k 번째 대역의 SINR 값인

를 사용하여 제 i 개인 가입자 단말기(202)에 k 번째 대역을 사용할 때 필요한 OFDM 심벌 수인

를 계산한다(S404). Based on the SINR value transmitted from the personal subscriber station 200, the radio access station 210 is a code packet size of data to be transmitted to the i th personal subscriber station 202.

And the SINR value of the k th band selected by the i &lt; th &gt;

Is the number of OFDM symbols required when using the k th band for the i &lt; th &gt;

To calculate (S404).

을 이용하여 각 대역당 요구되는 총 OFDM 심벌 수인

를 수학식 1을 사용하여 계산한다(S406).Radio access station 210 is calculated

Is the total number of OFDM symbols required per band

Is calculated using Equation 1 (S406).

Here, M is the number of personal subscriber stations 200 using AMC subchannels.

가 가장 큰 대역의 OFMD 심벌 수를

로 정의한다(S408).Radio access station 210

Is the number of OFMD symbols in the largest band.

It is defined as (S408).

가 실제 AMC 부채널로 사용할 수 있는 OFDM 심벌 수인

보다 큰 지 여부를 판단한다(S410).On the radio access station 210

Is the number of OFDM symbols available for the actual AMC subchannel

It is determined whether or not it is larger (S410).

가

보다 작은 경우, 제공된 OFDM 심벌 내에서 모든 개인 가입자 단말기(200)에 원하는 대역을 할당한다(S412).On the radio access station 210

end

If smaller, the desired band is allocated to all personal subscriber station 200 within the provided OFDM symbol (S412).

가

보다 크다고 판단된 경우, 라디오 액세스 스테이션(210)은 복수의 개인 가입자 단말기(200)가 요청하는 대역이 겹치는 충돌 대역이 존재하는지 판단한다(S414).On the radio access station 210

end

If it is determined to be larger, the radio access station 210 determines whether there is a collision band in which the bands requested by the plurality of individual subscriber stations 200 overlap (S414).

가

보다 큰 대역을 사용하는 개인 가 입자 단말기의 AMC 부채널 사용을 해제하고 제공된 OFDM 심벌 내에서 모든 개인 가입자 단말기(200)에 원하는 대역을 할당한다(S416). If there is no collision band in which the bands requested by the plurality of personal subscriber stations 200 overlap,

end

The AMC subchannel of the individual subscriber station using the larger band is released and the desired band is allocated to all the personal subscriber station 200 within the provided OFDM symbol (S416).

가 큰 순서대로 충돌 대역을 정렬하고, 이때

의 최대값인 대역을 k'로 정의한다(S418).When there is a collision band in which the bands requested by the plurality of personal subscriber stations 200 overlap each other, the radio access station 210 performs a collision band.

Sorts the collision bands in ascending order, where

The band which is the maximum value of is defined as k '(S418).

및

을 이용하여 각 대역당 요구되는 총 OFDM 심벌 수인

를 계산하고, 수학식 2를 만족하는 개인 가입자 단말기 h의 집합 A를 설정한다(S420).When the radio access station 210 refers to each personal subscriber station 200 as a personal subscriber station h, the number of allocation symbols for each band of the personal subscriber station h obtained when the personal subscriber station h is allocated the k 'band.

And

Is the total number of OFDM symbols required per band

Next, a set A of individual subscriber stations h satisfying Equation 2 is set (S420).

here,

,

및

를 계산한다(S422).Once the aggregation is established, the radio access station 210 redistributes the resources of band k 'to each individual subscriber station h and

,

And

Calculate (S422).

,

및

의 계산이 종료되면

를 최소로 하는 개인 가입자 단말기 h를 선택하여 AMC 부채널을 재분배한다(S424).On the radio access station 210

,

And

When the calculation of ends

The AMC subchannel is redistributed by selecting the personal subscriber station h with the minimum value (S424).

When the AMC subchannel redistribution ends from the radio access station 210 to the personal subscriber station h, the collision band list is updated (S426).

가 실제 AMC 부채널로 사용할 수 있는 OFDM 심벌 수인

보다 큰 지 여부를 판단한다(S428).After the update of the collision band list at the radio access station 210 ends, the radio access station 210

Is the number of OFDM symbols available for the actual AMC subchannel

It is determined whether it is larger (S428).

The above description is merely illustrative of the technical idea of the present invention, and those skilled in the art to which the present invention pertains may make various modifications and changes without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

As described above, according to the present invention, in the case of a portable Internet system using AMC, since the transmission rate varies depending on the channel state according to the user's location, fairness between users cannot be guaranteed, but AMC subchannels are allocated through resource redistribution. By reducing the number of OFDM sub-channels for the interval, the number of diversity subchannel users is increased, so that the amount of occupied data for each band is similarly distributed, thereby enabling efficient resource use, thereby increasing the overall yield of the system.

Claims (16)

 In an adaptive modulation and coding (AMC) subchannel allocation system in a portable Internet network using a personal subscriber station transmitting a signal to interference and noise ratio (SINR) value, A personal subscriber station accessing the portable Internet network using an Orthogonal Frequency Division Multiple Access (OFDMA) and using a portable Internet service; A radio access station serving as an access point (AP) of the personal subscriber station in a portable Internet system; An access control router controlling a plurality of said radio access stations; A home agent for routing packets from the Internet and external packet data service servers; A data service server for transmitting various content data in the form of a packet; An authentication server for authenticating network access of the personal subscriber station; NMS (Network Management System) server that functions to establish a central monitoring system of the equipment on the network to monitor, plan and analyze, and to store the relevant data to be used immediately necessary; And IP network connecting the access control router, the home agent, the authentication server and the NMS server Including; The personal subscriber station, AMC in a portable Internet network using a personal subscriber station transmitting a SINR value, characterized in that the band is selected for transmitting and receiving data through the portable Internet network, the SINR value of the selected band is measured and transmitted to the radio access station. Subchannel Allocation System. delete The method of claim 1, wherein the radio access station, It serves as a data repeater for wirelessly transmitting data received from the access control router to the personal subscriber station or transmitting data received from the personal subscriber station to the access control router, and manages radio resource management and control functions and handoffs. Personal subscriber station having support function, downlink multicast function, billing, statistical information generation and notification function, authentication and security function, and receiving SINR value transmitted by the personal subscriber station AMC Subchannel Allocation System in Mobile Internet Networks The method of claim 1, wherein the access control router, SINR value characterized by providing the handoff control function, IP routing and handoff management function between the radio access stations, billing service provision function to the billing server, IP multicast function, resource management and control function, authentication and security function. AMC subchannel allocation system in a portable Internet network using a personal subscriber station for transmitting a message.  A radio access station for allocating an AMC subchannel in a portable Internet network using a personal subscriber station transmitting an SINR value, A scheduler for determining resource allocation order of the personal subscriber station; A resource allocator configured to map the resource allocation order to an allocation band based on the resource allocation order determined by the scheduler; And OFDM transmitter which generates OFDM (Othogonal Frequency Division Multiplex) symbol signal and transmits it to access control router or personal subscriber station Radio access station of a portable Internet network using a personal subscriber station for transmitting the SINR value comprising a. The method of claim 5, wherein the scheduler, And a resource allocation order of the personal subscriber station using the SINR value and code packet size information transmitted from the personal subscriber station. The method of claim 5, wherein the resource allocation unit, The scheduler receives the resource allocation order and transmits the SINR value by mapping the resource allocation order to a predetermined band so that each individual subscriber station can be sequentially allocated resources. A radio access station of a portable internet network using a personal subscriber station. The method of claim 5, wherein the OFDM transmitter, When the band allocation to which the resource allocation order is mapped is transmitted from the resource allocator, an SINR value is generated by aligning packet data transmitted through the scheduler in the order of band mapping. A radio access station of a portable internet network using a personal subscriber station. A method for allocating an AMC subchannel in a portable Internet network using a personal subscriber station transmitting a SINR value, (a) a radio access station assigning a band to provide data communication to the personal subscriber station, the personal subscriber station calculating a SINR value of the allocated band; (b) if the SINR value of the band selected by the personal subscriber station is calculated, transmitting the SINR value to the radio access station; (c) the radio access station based on the SINR value transmitted from the personal subscriber station;

Calculating; (d) the radio access station is calculated

Is the total number of OFDM symbols required per band

Calculating; (e) at the radio access station

The number of OFMD symbols in this largest band

Defining as; (f) at the radio access station

Is the number of OFDM symbols available for the actual AMC subchannel

Determining whether greater than; (g) at the radio access station

Remind

If smaller, allocating the desired band to all the personal subscriber stations; (h) at the radio access station

Remind

If determined to be greater, the radio access station determining whether there is a collision band overlapping the bands requested by a plurality of personal subscriber stations; (i) when the collision band overlapping the bands requested by the plurality of personal subscriber stations does not exist,

Remind

Releasing the AMC subchannel usage of the personal subscriber station using a larger band and allocating the desired band to all the personal subscriber stations within the provided OFDM symbol; (j) when the collision band overlapping the bands requested by the plurality of personal subscriber stations exists, the radio access station determines the one of the collision bands.

Align the collision bands in ascending order, where

Defining a band that is the maximum value of k '; (k) When the radio access station refers to each of the personal subscriber station h as a personal subscriber station h, the number of band-specific allocation symbols of the personal subscriber station h obtained when the personal subscriber station h is allocated the k 'band

Wow

Is the total number of OFDM symbols required for each band

Calculating a and setting the set A of the personal subscriber stations h; (l) if the set A is established, the radio access station redistributes the resources of the band k 'to each of the personal subscriber stations h and each of the personal subscriber stations h;

,

And

Calculating; (m) at the radio access station

, remind

And said

When the calculation of is finished

Selecting the personal subscriber station h to minimize the distribution of the AMC subchannel; (n) updating the collision band list when the AMC subchannel distribution is terminated from the radio access station to the personal subscriber station h; And (o) after updating of the collision band list at the radio access station ends,

Is actually the number of OFDM symbols available for the AMC subchannel,

Steps to determine if greater than AMC subchannel allocation method in a portable Internet network using a personal subscriber station transmitting a SINR value comprising a. The method of claim 9, The step (a) is characterized in that the personal subscriber station selects four to five bands suitable for the band environment among the bands allocated by the radio access station and calculates the SINR value of the selected band. An AMC subchannel allocation method in a portable Internet network using a personal subscriber station transmitting SINR. The method of claim 9, Step (c) is a code packet size of data to be transmitted from the radio access station to the i &lt; th &gt; personal subscriber station.

Is the number of OFDM symbols required when using the k th band for the i &lt; th &gt;

AMC sub-channel allocation method in a portable Internet network using a personal subscriber station for transmitting the SINR value, characterized in that for calculating. The method of claim 9, Step (d) is,

Using

AMC subchannel allocation method in a portable Internet network using a personal subscriber station transmitting a SINR value, characterized in that the value of. The method of claim 12, Equation

M is the AMC subchannel allocation method in a portable Internet network using a personal subscriber station transmitting an SINR value, characterized in that the number of the personal subscriber station using the AMC subchannel. The method of claim 9, The step (h) is performed at the radio access station;

Remind

The AMC subchannel allocation method in a portable Internet network using a personal subscriber station transmitting an SINR value, characterized in that the radio access station uses the AMC subchannel when determined to be larger. The method of claim 9, Step (k) is,

An AMC subchannel allocation method in a portable Internet network using a personal subscriber station transmitting a SINR value, characterized by setting a set A of individual subscriber stations h satisfying the above. The method of claim 15, Equation

K 'is

An AMC subchannel allocation method in a portable Internet network using a personal subscriber station transmitting a SINR value characterized in that it satisfies.

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