JP3961391B2 - Wireless communication system - Google Patents

Description

（Ｓ７６）過去の割当てたフレーム長とＲＥＱメッセージキュー１１２０に蓄積された要求フレーム長を合計した時の帯域を計算する。
【０１７６】
Total_BW＝(Tpast_len＋Que_len)／(Tpast＋Tfuture)
（Ｓ７７）ＭＡＰメッセージ生成部１１２２は、上記計算結果に基づき、以下の帯域割当（新しい帯域の割当）指示内容に対応するＭＡＰメッセージを生成する。
【０１７７】
（Ｓ７７−▲１▼）Total_BW＞UBR帯域の場合（輻輳している場合）、各加入者無線局２０に割当てられている最小帯域（MIN帯域）の比で帯域を割り当てる。
【０１７８】
MIN帯域＝ΣMINspeed(SID)
割当帯域(SID)＝UBRの割当帯域×MINspeed(SID)/MIN帯域
ここで、MINspeed(SID)は、ＲＥＱメッセージキュー１１２０に蓄積されているＳＩＤの最小帯域である。また、MIN帯域とは、ＲＥＱメッセージキュー１１２０に接続されているＳＩＤの最小帯域の合計値である。
【０１７９】
また、この時の割当フレーム長Lは、
L＝割当帯域(SID)×T−Σframe_leng(SID,t)
となる。
【０１８０】
（Ｓ７７−▲２▼）Total_BW＜UBR帯域の場合、上述した第１の帯域割当方法のステップＳ５６−▲２▼，Ｓ５６−▲３▼に示した方法で各加入者無線局２０に帯域を割り当てる。
【０１８１】
なお、上述した第１〜第３の帯域割当方法において、帯域割当のパラメータとして、上述したフレーム長の変わりにタイムスロット長として割当てることも可能である。
【０１８２】
タイムスロット長で割当てる時は、以下の計算式により求める。
【０１８３】
割当タイムスロット数＝割当フレーム長／１タイムスロットのデータ長
なお、タイムスロットとは、上りチャネルまたは下りチャネルを固定時間毎に区切ったものである。
【０１８４】
このように、本発明に係わるシステムの基地局１０では、各加入者無線局２０からのデータ転送要求の合計帯域が回線帯域を超えた時、各加入者無線局２０に割り当てられた最大レート以下になるように帯域の割り当てを行なう他、各加入者無線局２０からのデータ転送要求の合計帯域が回線帯域を超えた時、各加入者無線局２０に割り当てられた最大レートの比あるいは最小レートの比に応じて帯域の割り当てを行なうようにしている。
【０１８５】
これらの帯域割当方法によれば、各加入者無線局２０からのデータ転送要求の合計帯域が回線帯域を超えた時にも、各加入者無線局２０の各フローに割り当てられた最大レートや最小レート等に応じて帯域が割り当てられることにより、各加入者無線局２０のサービス利用の公平性を保つことができる
この他、本発明は、上記し、且つ図面に示す実施例に限定することなく、その要旨を変更しない範囲内で適宜変形して実施できるものである。
【０１８６】
【発明の効果】
以上説明したように、本発明によれば、基地局に対向配置された加入者無線局において、同一優先度のデータを蓄積するバッファ領域が、コネクション種別に対応する複数のバッファ領域に分割されて成るバッファ手段を設け、同一優先度の入力データを、該入力データのコネクション種別に対応するバッファ領域に振り分けて蓄積せしめると共に、バッファ領域に蓄積されたデータを、コネクション毎に設定された出力レートの割合で出力するようにしたため、音声や画像等の複数の種類の情報通信をサービスするシステムにおいて、網が輻輳した時、遅延及び揺らぎの制約の厳しい情報通信サービスに対しても、各コネクション毎の遅延、帯域の公平性を維持することができる。
【０１８７】
また、本発明によれば、転送要求蓄積手段にキューとして蓄積されたデータ転送要求に含まれる割当要求帯域の合計値が回線帯域を超えた時、転送要求元の各加入者無線局に割り当てる帯域を、該各加入者無線局に割り当てられた最大レートの比、または、最小レートの比に応じて決定し、該当する各加入者無線局に割り当て指示する構成としたため、各加入者無線局からのデータ転送要求の合計帯域が回線帯域を超えた時にも、各加入者無線局の各フローに割り当てられた最大レートの比、または、最小レートの比に応じて帯域が割り当てられることにより、各加入者無線局のサービス利用の公平性を保つことができる。
【図面の簡単な説明】
【図１】本発明に係わる無線通信システムの全体構成を示す図。
【図２】加入者無線局の機能構成を示すブロック図。
【図３】図２における加入者無線局のバッファ２０４の構成を示す図。
【図４】基地局の無線アクセス処理部の機能構成を示すブロック図。
【図５】第１の帯域割当方法に基づく帯域割当計算アルゴリズムの流れを示すフローチャート。
【図６】第２の帯域割当方法に基づく帯域割当計算アルゴリズムの流れを示すフローチャート。
【図７】第３の帯域割当方法に基づく帯域割当計算アルゴリズムの流れを示すフローチャート。
【図８】従来システムの加入者無線局の機能構成を示すブロック図。
【符号の説明】
１０ 基地局
１１ 基地局の屋内装置（ＩＤＵ）
１１１ 無線アクセス処理部
１１１１，１１１８ バッファ
１１１２ ＭＡＣフレーム生成部
１１１３ 誤り訂正符号付加部
１１１４ 変調部
１１１５ 復調部
１１１６ 誤り検出／訂正部
１１１７ ＭＡＣフレーム組立部
１１１９ ＲＥＱメッセージ抽出部
１１２０ ＲＥＱメッセージキュー
１１２１ 帯域割当計算部
１１２２ ＭＡＰメッセージ生成部
１１３ スイッチ部
１１５ 制御部
１２ 基地局の屋外装置（ＯＤＵ）
２０，２０−１，２０−２，２０−３ 加入者無線局
２００ 入力端子
２０１ 入力バッファ
２０２ フィルタリング部
２０３ 振分書込み部
２０４ バッファ
２０４１−１，２０４１−２，…，２０４１−ｎ 種別毎バッファ
２０４２ 出力制御部
２０５ バッファサイズ設定部
２０６ 読出し制御部
２０７ ＭＡＣフレーム生成部
２０８ 誤り訂正符号付加部
２０９ 変調部
２１０ 周波数変換部
２１１ アンテナ
２１２ 復調部
２１３ 誤り検出／訂正部
２１４ ＭＡＣフレーム組立部
２１５ ＭＡＰメッセージ抽出部
２１６ 送出タイミング制御部
２１７ 出力バッファ
２１８ 出力端子
２１ 加入者無線局のＯＤＵ
２２ 加入者無線局のＩＤＵ
３０，３０−１，３０−２，３０−３ 加入者端末[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a radio communication system comprising a base station and a plurality of subscriber radio stations that perform one-to-many radio communication with the base station, and more specifically, transmission / reception between the base station in the subscriber radio station. The present invention relates to priority control of data and band allocation control for each subscriber radio station in a base station.
[0002]
[Prior art]
For example, as a system configuration for accessing a communication carrier's communication network from a subscriber terminal and using a communication service, a plurality of subscriber wireless devices are connected to a base station connected to a communication carrier's exchange or the like. Stations are arranged opposite to each other and a wireless section for performing point-to-multipoint (PTMP) communication between the base station and each subscriber radio station is provided, and a subscriber terminal connected to the subscriber radio station is provided. There is known a wireless communication system that enables wireless access to a communication network of a communication carrier.
[0003]
FIG. 8 is a diagram showing a configuration of a subscriber radio station 50 of this type of conventional system.
[0004]
In this subscriber radio station 50, processing when transmitting data from the subscriber terminal to the base station is performed as follows.
[0005]
Data transmitted from the subscriber terminal is input via the input terminal 500, temporarily stored in the input buffer 501, and then transmitted to the filtering unit 502.
[0006]
The filtering unit 502 looks at the destination address or source address of the data input from the subscriber terminal, compares it with the registered frame header, and determines whether the data can be transferred to the network. Only frames that are permitted to pass are passed.
[0007]
The buffer 503 is a buffer for speed control for accumulating the frames filtered by the filtering unit 502 and for reading from the read control unit 504.
[0008]
The read control unit 504 reads data from the buffer 503 and sends it to the MAC frame generation unit 505 at a timing permitted by the base station according to an instruction from the transmission timing control unit 514.
[0009]
The MAC frame generation unit 505 generates a MAC frame based on the cable modem standard, and the error correction code adding unit 506 adds an error correction code to the frame.
[0010]
The frame to which the error correction code is added is modulated by the modulation unit 507, frequency-converted by the frequency conversion unit 508, and then transmitted from the antenna 509 to the base station as a radio signal.
[0011]
In addition, processing when transmitting data from the base station to the subscriber terminal is performed as follows.
A radio signal transmitted from the base station is received by the antenna 509, converted from a radio frequency to a baseband frequency by the frequency converter 508, and then input to the demodulator 510.
[0012]
The demodulator 510 demodulates the signal (modulated signal) input from the frequency converter 508, converts it to a digital signal, and sends it to the error detector / corrector 511.
[0013]
The error detection / correction unit 511 detects the presence / absence of an error in an error correction code (provided by the transmission side) in the signal input from the demodulation unit 510, performs error correction when there is an error, and performs a frame assembly unit 512. Send to.
[0014]
The frame assembling unit 512 deletes the overhead of the data (MAC frame) input from the error detection / correction unit 511, assembles it into the original user data, and sends it to the buffer 503 and the MAP message extraction unit 513.
[0015]
The MAP message extraction unit 513 extracts a MAP message indicating transmission permission and transmission timing to each subscriber terminal sent from the base station from the data input from the frame assembly unit 512, and sends it to the transmission timing control unit 514. .
[0016]
The transmission timing control unit 514 analyzes the content of the message addressed to itself based on the extracted MAP message, and issues a frame transmission instruction to the reading-side read control unit 504.
[0017]
The read control unit 504 reads data from the buffer 503 based on the frame transmission instruction and sends it to the output buffer 515.
[0018]
The output buffer 515 converts the data read from the read control unit 504 into the line speed of the subscriber terminal for each priority and sends it to the corresponding subscriber terminal via the output terminal 515.
[0019]
As described above, in the subscriber radio station 50 of the conventional system, the data transmitted from the subscriber terminal is transmitted to the base station (transmitting side), and the data transmitted from the base station is transmitted to the subscriber terminal (receiving side). In both cases, the buffer 503 for storing the transfer data is provided, but the function for performing the individual priority control for those having a severe delay priority in the buffer 503 is not provided.
[0020]
For this reason, for example, when communication is performed by mixing data with different delays or discard priorities, such as voice and images, when the network becomes congested and discards occur, the data is severely limited in delay and fluctuation. However, the delay and bandwidth fairness for each user could not be maintained.
[0021]
On the other hand, in the base station that performs PTMP communication with the subscriber radio station 50, when allocating a band to each subscriber radio station 50, the message is stored in the order of messages stored in the data transfer request message queue through the FIFO memory.
[0022]
For this reason, data transfer of the subscriber radio station 50 having a large use band (many band use requests) is preferentially handled. As a result, fairness of service use of each subscriber radio station 50 can be maintained. It became no.
[0023]
[Problems to be solved by the invention]
As described above, in the conventional system, since the subscriber radio station does not perform individual priority control for those with severe delay priority in the buffer for storing transfer data on both the transmission side and the reception side, When communicating with mixed data with different delays or discard priorities such as images, when the network becomes congested and discards occur, it is not possible to maintain delay and bandwidth fairness for each user. was there.
[0024]
In addition, according to the conventional system, when a band is allocated to each subscriber radio station in the base station, the band is allocated to the corresponding subscriber radio station in the order in which the data transfer request is made, and thus a large band is used. As a result of preferential treatment of data transfer of subscriber radio stations, there is a problem that fairness of service use of each subscriber radio station cannot be maintained.
[0025]
The present invention eliminates the above problems and, when a plurality of types of information communication with different delay and fluctuation constraints coexist, the subscriber radio station applies priority control that matches each of the above information, thereby providing a network. It is an object of the present invention to provide a wireless communication system capable of maintaining delay and bandwidth fairness even for information communication services with severe restrictions on delay and fluctuation when congestion occurs.
[0026]
Further, the present invention prevents a bandwidth from being preferentially allocated to a subscriber radio station having a large use band when allocating a bandwidth from a base station to each subscriber radio station. An object of the present invention is to provide a wireless communication system capable of maintaining fairness of service use.
[0027]
[Means for Solving the Problems]
In order to achieve the above object, the invention according to claim 1 is a wireless communication system comprising a base station and a plurality of subscriber wireless stations that perform one-to-many wireless communication with the base station. Is a buffer means in which a buffer area for storing data of the same priority is divided into a plurality of buffer areas corresponding to the connection type, and a buffer corresponding to the connection type of the input data for the input data of the same priority. It is characterized by comprising: an allocation writing means for distributing and storing in an area; and a read control means for outputting the data stored in the buffer area at a rate of an output rate set for each connection.
[0028]
The invention according to claim 2 is a radio communication system comprising a base station and a plurality of subscriber radio stations that perform one-to-many radio communication with the base station, wherein the base station receives signals from the subscriber radio stations. From the data Includes allocation request bandwidth A transfer request extracting means for extracting a data transfer request; and a data transfer request from each of the subscriber radio stations extracted by the transfer request extracting means. As a queue Transfer request storage means for storing, and data transfer requests stored in the transfer request storage means Including the total value of the allocation request bandwidth included, Bandwidth allocation calculation means for calculating a parameter value for determining a bandwidth to be allocated to each subscriber radio station as a transfer request source, and the bandwidth allocation calculation means When the total value of the allocation request bandwidths calculated by (1) exceeds the line bandwidth, the bandwidth allocated to each subscriber radio station of the transfer request source is determined according to the ratio of the maximum rate allocated to each subscriber radio station. A bandwidth allocation message generating means for determining and generating a bandwidth allocation message for instructing the allocation of the bandwidth; and a transmitting means for transmitting the bandwidth allocation message to a corresponding subscriber radio station, wherein the subscriber radio station comprises: And a transmission timing control means for receiving the bandwidth allocation message from the base station and controlling the timing of data transmission according to the allocated bandwidth indicated by the message.
[0029]
The invention described in claim 3 In a radio communication system comprising a base station and a plurality of subscriber radio stations that perform one-to-many radio communication with the base station, the base station determines an allocation request bandwidth from the received data from the subscriber radio station. A transfer request extracting means for extracting a data transfer request, a transfer request storing means for storing a data transfer request from each subscriber radio station extracted by the transfer request extracting means as a queue, and a transfer request storing means. A bandwidth allocation calculation means for calculating a parameter value for determining a bandwidth to be allocated to each subscriber radio station of the transfer request source, including a total value of allocation request bandwidths included in the accumulated data transfer request; and When the total value of the calculated allocation request bandwidth exceeds the line bandwidth, the bandwidth allocated to each subscriber radio station of the transfer request source is allocated to each subscriber radio station Band allocation message generation means for generating a band allocation message that is determined according to the ratio of the small rate and instructing the allocation of the band, and transmission means for transmitting the band allocation message to the corresponding subscriber radio station. The subscriber radio station includes transmission timing control means for receiving the band allocation message from the base station and controlling the timing of data transmission according to the allocated band indicated by the message. It is characterized by that.
[0032]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
[0033]
FIG. 1 is a diagram showing an overall configuration of a radio communication system according to the present invention.
[0034]
This system includes a base station 10, a plurality of subscriber radio stations 20 (20-1, 20-2, 20-3) arranged opposite to the base station 10 across a radio section, and each subscriber radio station. 20 and a subscriber terminal 30 (30-1, 30-2, 30-3) connected to 20.
[0035]
Here, the base station 10 accommodates a plurality of users (user terminals 30) by communicating with a subscriber radio station 20 in a radio service area (cell) in a range of several kilometers by multi-channel access control, for example. Here, more users can be accommodated depending on the capability of the base station 10.
[0036]
Although not shown in FIG. 1, in the present system, cells other than the cells managed by the base station 10 can exist. In this case, each cell also has one base station 10. A plurality of subscriber radio stations 20 are arranged.
[0037]
In FIG. 1, between the base station 10 and each of the subscriber radio stations 20-1, 20-2 and 20-3, an uplink (from the subscriber radio station 20 to the base station 10) and a downlink (base station) are respectively shown. 10 to the subscriber radio station 20 direction), and PTMP communication between the base station 10 and each of the subscriber radio stations 20-1, 20-2, and 20-3 is performed using both of these lines. Similar PTMP communication is performed in other cells.
[0038]
In the present system, the base station 10 is connected to a public network (not shown) via the communication line 40. Furthermore, the public network is connected to a communication network such as an ATM network, an I-private network, a communication network such as the Internet or an intranet, a frame relay network, or an N-ISDN.
[0039]
At least one of these networks is provided with a switching center (not shown) of a telecommunications carrier, and the switching center manages data corresponding to various services provided by the telecommunications carrier. (Hereinafter referred to as a service system).
[0040]
A subscriber to a communication service operated by a telecommunications carrier accesses the service system of the telecommunications carrier from the subscriber terminal 30 via PTMP communication between the subscriber radio station 20 and the base station 10. Communication service is available.
[0041]
In this system, the base station 10 includes an indoor unit (IDU: INDOOR UNIT) 11 and an outdoor unit (ODU: OUTDOOR UNIT) 12.
[0042]
The IDU 11 includes a radio access processing unit 111 having a function of modulating / demodulating data transmitted / received to / from the ODU 12, a band allocation function for each subscriber radio station, etc., and a public network via the radio access processing unit 111 and the communication line 40. Are provided with a switch unit 113 for exchanging data transmitted / received between them and a control unit 115 for controlling the operation of the entire IDU 11.
[0043]
On the other hand, the subscriber radio station 20 has an interface function between an outdoor unit (ODU) 21 that performs radio communication opposite to the ODU 12 of the base station 10 and the subscriber terminal 30 installed in the subscriber premises. And an indoor unit (IDU) 22.
[0044]
Note that the subscriber radio station 20 is not necessarily configured to be separated into the ODU 21 and the IDU 22, and may be configured as a radio apparatus in which the ODU 21 and the IDU 22 are integrated.
[0045]
As the subscriber terminal 30, various communication terminals such as a 10Base-T terminal (a terminal such as a personal computer realized by a 10Base-T connection method) and an ISDN terminal are used.
[0046]
A radio section between the ODU 12 of the base station 10 and the ODU 21 of the subscriber radio station 20 is operated by a multi-channel access method.
[0047]
As a multi-channel access method, the uplink signal output from the subscriber radio station 20 toward the base station 10 uses the same frequency in the plurality of subscriber radio stations 20, and the base station 10 sends to each subscriber radio station 20. Then, a transmission permission timing signal is transmitted, and only the subscriber radio station having the permission is output to the base station 100 at the permitted timing.
[0048]
As for the downlink signal from the base station 10 to the subscriber radio station 20, the base station 10 transmits the data to each subscriber radio station 20 in a broadcast format, and each subscriber radio station 20 receives only the signal addressed to itself. To do.
[0049]
The upstream and downstream frequencies may be different or the same. However, in the case of being the same, it is necessary to carry out uplink and downlink transfer timing in a time division manner.
[0050]
In the system of the present invention shown in FIG. 1, an operation when a certain subscriber terminal 30 accesses a service system of a communication carrier will be described.
[0051]
In this case, when a predetermined access operation is performed at the subscriber terminal 30, an access request signal corresponding to the operation is generated and input to the corresponding subscriber radio station 20.
[0052]
The subscriber radio station 20 transmits an access request signal input from the subscriber terminal 30 connected to the own station to the radio section via the IDU 22 and the ODU 21.
[0053]
In the base station 10 facing the subscriber radio station 20 across this radio section, the access request signal transmitted from the subscriber radio station 20 is received by the ODU 12 and controlled via the radio access processing unit 111 in the IDU 11. Forward to the unit 115.
[0054]
The control unit 115 performs control for connecting the subscriber terminal 30 to the service system of the communication carrier via the switch unit 113 based on the access request signal from the subscriber terminal 30.
[0055]
After the subscriber terminal 30 is connected to the service system of the telecommunications carrier by this control, data from the service system is transmitted to the radio section via the switch unit 113, the radio access processing unit 111, and the ODU 12 of the base station 10. After being received by the ODU 21 at the opposing subscriber radio station 20, it is transmitted to the subscriber terminal 30 via the IDU 22.
[0056]
In contrast to the above, the data sent from the subscriber terminal 30 is sent to the radio section via the IDU 22 and ODU 21 of the corresponding subscriber radio station 20 and received by the ODU 12 at the opposite base station 10. Thereafter, the data is transmitted to the service system via the wireless access processing unit 111 and the switch unit 113.
[0057]
At the time of communication between the subscriber terminal 30 and the service system of the carrier, the subscriber radio station 20 to which the subscriber terminal 30 is connected has one base station 10 shared with each other subscriber radio station 20. To perform PTMP communication.
[0058]
In the communication between the base station 10 and the subscriber radio station 20 when accessing the service system of the communication carrier from the subscriber terminal 30 described above, the subscriber radio station 20 uses the subscriber terminal for the data received from the base station 10. A buffer area in which data having the same priority is accumulated into a plurality of buffer areas corresponding to connection types when sending data to 30 and sending data inputted from the subscriber terminal 30 to the base station 10 Means for distributing the input data of the same priority to the buffer area corresponding to the connection type of the input data and storing the data stored in the buffer area at the rate of the output rate set for each connection. Perform priority control to output.
[0059]
At this time, the base station 10 determines a band to be allocated to each subscriber radio station 20 as a transfer request source based on a data transfer request from each of the opposing subscriber radio stations 20, and a band for instructing the allocation of the band Bandwidth allocation control for generating an allocation message and transmitting it to the subscriber radio station 20 is performed.
[0060]
In this bandwidth allocation control, for example, when the total bandwidth of data transfer requests from each subscriber radio station 20 exceeds the line bandwidth, each subscription is based on the maximum rate or the minimum rate allocated to each subscriber radio station 20. A band is allocated to the person radio station 20.
[0061]
Hereinafter, the configuration of the subscriber radio station 20 and the base station 10, the priority control in the subscriber radio station 20, and the bandwidth allocation control in the base station 10 will be described in detail.
[0062]
FIG. 2 is a block diagram showing a functional configuration of the subscriber radio station 20 in the system according to the present invention. In FIG. 2, the ODU 21 and the IDU 22 of the subscriber radio station 20 are not particularly divided, and the overall configuration is shown.
[0063]
As shown in FIG. 2, the subscriber radio station 20 includes an input terminal 200, an input buffer 201, a filtering unit 202, an allocation writing unit 203, a buffer 204, a buffer size setting unit 205, a read control unit 206, and a MAC frame generation unit. 207, error correction code addition unit 208, modulation unit 209, frequency conversion unit 210, antenna 211, demodulation unit 212, error detection / correction unit 213, MAC frame assembly unit 214, MAP message extraction unit 215, transmission timing control unit 216, An output buffer 217 and an output terminal 218 are provided.
[0064]
In FIG. 2, the subscriber terminal 30 is connected to the input terminal 200 and the output terminal 218 of the subscriber radio station 20, and the base station 10 is disposed opposite to the antenna 211 side across the radio section. That is, the subscriber radio station 20 has a terminal interface function with the subscriber terminal 30 and a radio interface function with the base station 10.
[0065]
Regarding the operation of the subscriber radio station 20, first, the data transmission operation from the terminal interface side to the radio interface side, that is, the transmission side until receiving data from the subscriber terminal 30 and sending the data to the base station 10 Will be described.
[0066]
Data sent from the subscriber terminal 30 is input to the subscriber radio station 20 via the input terminal 200 and temporarily stored in the input buffer 201.
[0067]
The data stored in the input buffer 201 is then sent to the filtering unit 202.
[0068]
The filtering unit 202 looks at the destination address or source address of the data input from the subscriber terminal 30 and compares it with the registered frame header to determine whether the data can be transferred to the network. Then, only the frame for which transfer is permitted is passed and sent to the distribution writing unit 203.
[0069]
The distribution write 203 is provided for each priority of the buffer 204 in the subsequent stage according to the destination address and the source address by monitoring any one of the layer 2 to layer 4 headers of the frame input from the filtering unit 202. It is determined which of the buffer areas to transfer to.
[0070]
The buffer 204 includes buffers 1, 2,..., Buffer n for storing data having different priorities, and the buffers 1, 2,..., Buffer n are connected for each QOS or service flow. It is divided into buffer areas corresponding to types (buffer areas for each type), and the frame length that can be stored in each type of buffer area can be variably set.
[0071]
The buffer size setting unit 205 performs processing for determining the buffer size of the type-specific buffer area divided for each connection type (QOS or service flow) of the buffer 204.
[0072]
For example, in a buffer area for each type in which QOS data with severe delay restrictions is accumulated, such as a voice / image communication service, the buffer capacity is reduced in order to reduce the frame residence time and the difference in frame residence time (jitter). To do.
[0073]
In this type buffer area, QOS is assigned for each SID (service ID), but for each type buffer with severe delay restrictions, a buffer frame is divided for each destination address or source address, and a bandwidth is assigned for each address. For example, as shown in the following equation, frames are output at the ratio of each band.
[0074]
Output ratio of address I = band of address I / band of Σ address k (1)
FIG. 3 is a diagram illustrating the configuration of the buffer 204.
[0075]
In FIG. 3, each type buffer 2041-1, 2041-2,..., 2041-n is obtained by further dividing the buffer 1, buffer 2,..., Buffer n of the buffer 204 shown in FIG.
[0076]
The buffer 2041-1, 2041-2,..., 2041-n for each type in the buffer 204 is, for example, a destination MAC address, a source MAC address, a destination IP address, a source IP address, (destination IP address + port number). , (Source IP address + port number) and the like.
[0077]
At the time of data transfer to the buffer 204 having such a structure, the distribution writing unit 203 looks at the contents of data (packets) input from the filtering unit 202, and determines the buffers 2041-1, 2041-2,. , 2041-n, which buffer is to store the data is selected.
[0078]
When the read permission signal is output from the read control unit 206, the output control unit 2042 of the buffer 204 is provided with buffers 2041-1 and 2041 for each type in proportion to the speed of USG (fixed rate) multiplexed in the SID. The stored data is read from −2,..., 2041-n and sent to the MAC frame generation unit 207.
[0079]
The reading control at that time is performed in accordance with the above equation (1).
[0080]
As described above, in the subscriber radio station 20 according to the present invention, the buffer areas (buffer 1, buffer 2,..., Buffer n) that store data of the same priority are a plurality of buffer areas (types) corresponding to the connection type. , 2041-n) is provided, and the input data having the same priority is distributed to the type-specific buffer area corresponding to the connection type of the input data. In addition to accumulating, the data accumulated in the buffer area for each type is output at the rate of the output rate set for each connection.
[0081]
By such priority control processing, the read control in the read control unit 206 is assigned according to the ratio of each connection, so that when a large amount of data flows due to a failure of some USGs, it affects other USG connections. (A large amount of data does not impose data transmission on other USG connections).
[0082]
In addition, delay and fluctuation time can be guaranteed regardless of the input state from each connection. That is, in a flow in which a plurality of fixed rate services such as USG are joined, the delay and bandwidth fairness of each connection can be maintained.
[0083]
The read control unit 206 uses a method according to the above equation (1) at a timing permitted from the base station 10 according to an instruction (read permission signal) from a transmission timing control unit 216 described later, and a buffer 2041 for each QOS. 1, 2041-2,..., 2041-n are read out and sent to the frame generation unit 207.
[0084]
The frame generation unit 207 generates a MAC frame based on a DOCSIS (Data Over Cable Service Interface Specification) standard, which is a standard for a cable modem communication method.
[0085]
Next, the error correction code adding unit 208 adds an error correction code of a Reed-Solomon convolutional code standardized by BWIF (Broadband Wireless Internet Forum) to the MAC frame generated by the frame generation unit 207.
[0086]
The modulation unit 209 modulates the MAC frame using the OFDM modulation method standardized by BWIF, and sends the modulated MAC frame to the frequency setting unit 210.
[0087]
The frequency setting unit 210 converts the modulated signal into a frequency to be radiated wirelessly, and radiates a transmission radio wave toward the base station 10 by the antenna 211.
[0088]
Next, a data transmission operation from the radio interface side to the terminal interface side, that is, an operation on the reception side until data is received from the base station 10 and the data is output to the subscriber terminal 30 will be described.
[0089]
The subscriber radio station 20 receives the radio signal radiated from the base station 10 by the antenna 211, converts the radio frequency into a baseband signal by the frequency conversion unit 210, and outputs it to the demodulation unit 212.
[0090]
The demodulator 212 demodulates the OFDM signal modulated signal determined by the BWIF, converts it to a digital signal, and outputs it to the error detector / corrector 213.
[0091]
The error detection / correction unit 213 detects the presence or absence of an error in the error correction code given from the transmission side from the demodulated data, performs error correction when there is an error, and then sends the data to the frame assembly unit 214. Output.
[0092]
The frame assembling unit 214 deletes the MAC frame overhead given by the DOCSIS standard from the input data from the error detection / correction unit 213, assembles it into the original user data, extracts the distribution writing unit 203 and the MAP message on the receiving side To the unit 215.
[0093]
The MAP message extraction unit 215 extracts, from the input data from the frame assembly unit 214, a MAP message indicating transmission permission and transmission timing to each subscriber terminal 30 transmitted from the base station 10, and a transmission timing control unit 216. Output to.
[0094]
The transmission timing control unit 216 analyzes the content of the message addressed to itself based on the extracted MAP message, and issues a frame transmission instruction to the reading-side read control unit 206.
[0095]
On the other hand, the distribution write unit 203 on the reception side performs the same operation as the distribution write unit 203 on the transmission side, and the destination address of the headers of layers 2 to 4 of the data (user frame) input from the frame assembly unit 214 is transmitted. From the original address, it is determined to which buffer of the buffers 2041-1, 2041-2,..., 2041-n for each QOS in the buffer 204, and based on this determination, it is distributed to the corresponding buffer and stored.
[0096]
Similarly to the transmission side, the buffer size setting unit 205 on the reception side determines the size of the buffers 2041-1, 2041-2,..., 2041-n for each type divided for each QOS or each service flow in the buffer 204. Perform processing.
[0097]
The read control unit 206 reads data from the buffers 2041-1, 2041-2,..., 2041-n allocated for each QOS in the buffer 204, and converts the data to the line speed to the subscriber terminal 30 for each priority. To the output buffer 217.
[0098]
As an example of the data read algorithm of the read control unit 206 at this time, there is an algorithm corresponding to the following priority control.
[0099]
Fixed priority method:
A delay priority is assigned to each type of buffer 2041-1, 2041-2,..., 2041-n, and when a frame is stored in a higher delay priority, it is read from the higher priority type buffer. When no frame is stored in the high-priority type buffer, the next priority type buffer is read.
[0100]
Bandwidth securing method:
An output bandwidth is assigned to each type of buffer 2041-1, 2041-2,..., 2041-n, and frames stored in each type of buffer are read in proportion to the assigned bandwidth.
[0101]
Frames read from the various buffers 2041-1, 2041-2,..., 2041-n to the output buffer 217 in accordance with the algorithm of the fixed priority method or the bandwidth securing method are output from the output buffer 217 via the output terminal 218. It is sent to the subscriber terminal 30.
[0102]
With the above priority control, the subscriber radio station 20 separates the buffer 204 for storing the transfer data on both the transmission side and the reception side for each QOS, and for QOS with severe delay priority, a buffer corresponding to the delay constraint time. The delay constraint can be observed by setting the amount and preferentially transferring.
[0103]
Next, band allocation control in the base station 10 will be described.
[0104]
In the base station 10, when there is a data transfer request from each subscriber radio station 20 in the cell that the own station has jurisdiction over, the radio access processing unit 111 controls the bandwidth allocation to the request source.
[0105]
FIG. 4 is a diagram illustrating a configuration of the radio access processing unit 111 of the base station 10.
[0106]
As shown in FIG. 4, the wireless access processing unit 111 includes a buffer 1111, a MAC frame generation unit 1112, an error correction code addition unit 1113, a modulation unit 1114, a demodulation unit 1115, an error detection / correction unit 1116, a frame assembly unit 1117, A buffer 1118, a REQ message extraction unit 1119, a REQ message queue 1120, a bandwidth allocation calculation unit 1121, and a MAP message generation unit 1122 are configured.
[0107]
In the radio access processing unit 111, processing at the time of data transmission from the switch unit 112 to the subscriber radio station 20 is performed as follows.
[0108]
In this process, the buffer 1111 temporarily accumulates the frames input from the switch unit 112, and outputs the frames to the MAC frame generation unit 1112 according to the timing of the MAC frame generation unit 1112.
[0109]
Here, the buffer 1111 may be configured to have a priority control function for each QOS or each service flow.
[0110]
In this case, as the buffer 1111, a buffer having a buffer area for storing data for each delay priority is used, and when data having a high delay priority is stored in the corresponding buffer area, Control may be performed to output data stored in another buffer area having a lower priority than this.
[0111]
The MAC frame generation unit 1112 decomposes the frame input from the buffer 1111 into MAC frames based on the DOCSIS standard.
[0112]
The error correction code addition unit 1113 adds an error correction code to the MAC frame from the MAC frame generation unit 1112 based on the BWIF standard, and inputs the error correction code to the modulation unit 1114.
[0113]
The modulation unit 1114 modulates the MAC frame to which the error correction code is added based on the BWIF specification. The signal modulated by the modulation unit 1114 is then transmitted to the ODU 12 and transmitted to the subscriber radio station 20 as a radio signal.
[0114]
Next, processing at the time of data transmission from the subscriber radio station 20 toward the switch unit 112 in the radio access processing unit 111 will be described.
[0115]
In this process, the radio signal transmitted from the subscriber radio station 20 is received by the ODU 12 and input to the demodulator 1115 of the radio access processor 111 as a digital modulation signal.
[0116]
The demodulator 1115 demodulates the digital modulation signal input from the ODU 12 into a digital signal and inputs the digital signal to the error detection / correction unit 1116.
[0117]
The error detection / correction unit 1116 extracts an error correction signal given on the subscriber radio station 20 side from the input signal from the demodulation unit 1115 to detect the presence or absence of an error, and an error can be detected and corrected. If there is, correct this and send it to the frame assembly unit 1117. In this error correction process, for example, a Reed-Solomon code or a convolutional code is used.
[0118]
The frame assembling unit 1117 receives the input signal from the error detection / correction unit 1116, assembles the data decomposed into MAC frames on the subscriber radio station 20 side into the original frame, and sends the original frame to the buffer 1118.
[0119]
The buffer 1118 temporarily stores the MAC frame assembled by the frame assembly unit 1117 until it is output to the switch unit 112.
[0120]
The frames stored in the buffer 1118 are then output to the communication network via the switch unit 113.
[0121]
Prior to the above-described data transmission / reception, the radio access processing unit 111 receives a data transfer request from each subscriber radio station 20, and thereby assigns a band used for the data transfer to the requesting subscriber radio station 20. To do.
[0122]
Hereinafter, the bandwidth allocation control operation in the radio access processing unit 111 will be described.
[0123]
First, when data to be transmitted is generated in each subscriber radio station 20, the subscriber radio station 20 sends a data transfer request message (hereinafter referred to as a REQ message) to the base station 10.
[0124]
The REQ message is transmitted from the subscriber radio station 20 to the base station 10 when data to be transmitted from the subscriber terminal 30 is input to the subscriber radio station 20.
[0125]
This REQ message is inserted into the header part of the MAC frame generated by the same method as the data transmission described above and transmitted to the base station 10.
[0126]
On the other hand, as described above, the base station 10 receives the radio signal (MAC frame) transmitted from the subscriber radio station 20 by the ODU 12, and then, in the radio access processing unit 111 of the IDU 11, the demodulator 1115, the error detection / Processing is performed through the correction unit 1116, and the frame assembly unit 1117 restores the original frame.
[0127]
During this reception process, the REQ message extraction unit 1119 extracts the REQ message from the contents of the header portion of the restored received frame, and temporarily stores the extracted REQ message in the REQ message queue 1120.
[0128]
The bandwidth allocation calculation unit 1121 sequentially reads out the REQ messages stored in the REQ message queue 1120 and performs a calculation for obtaining a bandwidth to be allocated according to the REQ message.
[0129]
The bandwidth allocation calculation algorithm in the bandwidth allocation calculation unit 1121 will be described in detail later.
[0130]
The calculation result in the bandwidth allocation calculation unit 1121 is notified to the MAP message generation unit 1122.
[0131]
The MAP message generation unit 1122 determines a band to be allocated to the corresponding subscriber radio station 20 (transfer request source) based on the calculation result of the band allocation calculation unit 1121, and performs a message for instructing allocation to the band, that is, data transfer. A message to be permitted (bandwidth allocation message: MAP message) is generated.
[0132]
The MAP message generated by the MAP message generation unit 1122 is assembled into a MAC frame by the MAC frame generation unit 1112 and sent to the subscriber radio station 20 that is the transfer request source, as in the data transmission described above.
[0133]
When the transfer request source subscriber radio station 20 receives the MAC frame transmitted from the base station 10, the MAP message extraction unit 215 extracts the MAP message from the header portion of the MAC frame.
[0134]
This MAP message is sent to the transmission timing control unit 216. The transmission timing control unit 216 controls the transmission timing of data from the subscriber terminal 30 that is the target of the transfer request according to the bandwidth indicated by the MAP message received from the MAP message extraction unit 215.
[0135]
Specifically, the transmission timing control unit 216 instructs the base station 10 to allocate the data using the MAP message in a situation where the data transmitted from the subscriber terminal 30 (data to be transmitted) is already stored in the buffer 204. A read permission signal is sent to the read control unit 206 at a timing commensurate with the designated band.
[0136]
The read control unit 206 reads the data from the buffer 204 based on the read permission signal. The read data is transmitted to the base station 10 via the MAC frame generation unit 207, the error correction code addition unit 208, the modulation unit 209, the frequency conversion unit 210, and the antenna 211.
[0137]
Next, a bandwidth allocation calculation algorithm in the bandwidth allocation calculation unit 1121 of the base station 10 will be described.
[0138]
As a method of allocating a band from the base station 10 side to the subscriber wireless station 20 that is a data transfer request source, for example, there are the following three methods.
[0139]
First bandwidth allocation method:
When the data transfer request bandwidth from each subscriber radio station 20 exceeds the line bandwidth, the bandwidth to each corresponding subscriber radio station 20 is set so as to be equal to or less than the maximum rate assigned to each subscriber radio station 20. assign.
[0140]
The bandwidth allocation calculation algorithm based on this method is performed according to the flowchart shown in FIG.
[0141]
(S51) The REQ message extraction unit 1119 extracts the REQ message from the data transmitted from each subscriber radio station 20.
[0142]
(S52) The extracted REQ message is stored in the REQ message queue 1120.
[0143]
(S53) The bandwidth allocation calculation unit 1121 extracts the first REQ message from the REQ message queue 1120.
[0144]
(S54) Based on the extracted REQ message, the bandwidth allocation calculation unit 1121 calculates the total value [FL_total (SID)] and the speed [Speed (SID)] of the frame length for each SID permitted in the past T time as Calculate with
[0145]
Total frame length allocated for each SID in the past T time [FL_total (SID)]
FL_total (SID) = Σframe-Length (SID, t)
Here, frame-Length (SID, t) represents the frame length assigned to each REQ message within the past T time for each SID.
[0146]
Note that the currently extracted SID is calculated by adding the extracted requested frame length.
[0147]
Speed of each SID in the past T time [Speed (SID)]
Speed (SID) = FL_total (SID) / T
(S55) The bandwidth allocation calculation unit 1121 obtains a total value (Speed_total) of speeds for each SID in the past T time.
[0148]
Speed_total = ΣSpeed (SID)
(S56) The MAP message generator 1122 generates a MAP message corresponding to the following band allocation (new band allocation) instruction content based on the calculation result.
[0149]
(S56- <1>) When Speed_total <UBR band and Speed (SID) <MAXspeed (SID), the requested frame length is permitted for the extracted SID.
[0150]
Here, MAXspeed (SID) is the maximum rate assigned to the SID.
(S56- <2>) When Speed_total <UBR band and Speed (SID)> MAXspeed (SID), a band is allocated so that the extracted SID has MAX_speed.
[0151]
Here, the allocation frame length L is
L = MAX_speed (SID) × T−FL_total (SID) −REQ_NOW_LG
Here, REQ_NOW_LG represents the request frame length of the currently read REQ message.
[0152]
(S56- [3]) When Speed_total> UBR band, the excess is deleted and the band is allocated. The deleted bandwidth allocation calculation is based on the following formula.
[0153]
L = UBR band × T−ΣFL_total (SID) −REQ_NOW_LG
Second bandwidth allocation method:
When the total bandwidth of the transfer requests from each subscriber radio station 20 exceeds the line bandwidth, the bandwidth to each corresponding subscriber radio station 20 according to the ratio of the maximum rates assigned to each subscriber radio station 20 Assign.
[0154]
The bandwidth allocation calculation algorithm based on this method is performed according to the flowchart shown in FIG.
[0155]
(S61) The REQ message extraction unit 1119 extracts the REQ message from the data transmitted from each subscriber radio station 20.
[0156]
(S62) The extracted REQ message is stored in the REQ message queue 1120.
[0157]
(S63) The bandwidth allocation calculation unit 1121 calculates the frame length (Que_len) accumulated in the REQ message queue 1120 by the following equation.
[0158]
Que_len = ΣREQ (SID, i)
Here, REQ (SID, i) represents the request frame length of the REQ message stored in the REQ message queue 1120.
[0159]
(S64) The bandwidth when the total request frame length T accumulated in the REQ message queue 1120 is allocated is calculated.
[0160]
T = Que_Len / (UBR bandwidth = total bandwidth-USG bandwidth)
(S65) The total value of the frame length up to the past Tpast and the frame length up to T time later is calculated.
[0161]
Tpast_Len = ΣΣFrame_leng (SID, t)
(S66) The bandwidth when the previously allocated frame length and the requested frame length accumulated in the REQ message queue 1120 are summed is calculated.
[0162]
Total_BW = (Tpast_len + Que_len) / (Tpast + Tfuture)
(S67) Based on the calculation result, the MAP message generation unit 1122 generates a MAP message corresponding to the following band allocation (new band allocation) instruction content.
[0163]
(S67- (1)) When Total_BW> UBR band (when congested), the band is allocated by the ratio of the maximum band (MAX band) allocated to each subscriber radio station 20.
[0164]
MAX bandwidth = ΣMAXspeed (SID)
Allocated bandwidth (SID) = UBR allocated bandwidth x MAXspeed (SID) / MAX bandwidth
Here, MAXspeed (SID) is the maximum bandwidth of the SID accumulated in the REQ message queue 1120. The MAX band is the total value of the maximum bands of SIDs connected to the REQ message queue 1120.
[0165]
Also, the allocation frame length L at this time is
L = allocated bandwidth (SID) x T-Σframe_leng (SID, t)
It becomes.
[0166]
(S67- (2)) If Total_BW <UBR band, the band is allocated to each subscriber radio station 20 by the method shown in steps S56- (2) and S56- (3) of the first band allocation method described above. .
[0167]
Third bandwidth allocation method:
When the total bandwidth of the transfer request from each subscriber radio station 20 exceeds the line bandwidth, the bandwidth to each corresponding subscriber radio station 20 according to the ratio of the minimum rates assigned to each subscriber radio station 20 Assign.
[0168]
The bandwidth allocation calculation algorithm based on this method is performed according to the flowchart shown in FIG.
[0169]
(S71) The REQ message extraction unit 1119 extracts the REQ message from the data transmitted from each subscriber radio station 20.
[0170]
(S72) The extracted REQ message is stored in the REQ message queue 1120.
[0171]
(S73) The bandwidth allocation calculation unit 1121 calculates the frame length (Que_len) accumulated in the REQ message queue 1120 by the following equation.
[0172]
Que_len = ΣREQ (SID, i)
Here, REQ (SID, i) represents the request frame length of the REQ message stored in the REQ message queue 1120.
[0173]
(S74) The bandwidth when the total requested frame length T accumulated in the REQ message queue 1120 is allocated is calculated.
[0174]
T = Que_Len / (UBR band = total band-USG band)
(S75) The sum of the frame length up to the past Tpast and the frame length up to T time is calculated.
[0175]

(S76) The bandwidth when the previously allocated frame length and the requested frame length accumulated in the REQ message queue 1120 are summed is calculated.
[0176]
Total_BW = (Tpast_len + Que_len) / (Tpast + Tfuture)
(S77) The MAP message generation unit 1122 generates a MAP message corresponding to the following band allocation (new band allocation) instruction content based on the calculation result.
[0177]
(S77- [1]) When Total_BW> UBR band (when congested), the band is allocated by the ratio of the minimum band (MIN band) allocated to each subscriber radio station 20.
[0178]
MIN band = ΣMINspeed (SID)
Allocated bandwidth (SID) = UBR allocated bandwidth x MINspeed (SID) / MIN bandwidth
Here, MINspeed (SID) is the minimum bandwidth of the SID accumulated in the REQ message queue 1120. The MIN band is the total value of the minimum bands of SIDs connected to the REQ message queue 1120.
[0179]
Also, the allocation frame length L at this time is
L = allocated bandwidth (SID) x T-Σframe_leng (SID, t)
It becomes.
[0180]
(S77- (2)) If Total_BW <UBR band, the band is allocated to each subscriber radio station 20 by the method shown in steps S56- (2) and S56- (3) of the first band allocation method described above. .
[0181]
In the first to third band allocation methods described above, it is also possible to allocate as a time slot length instead of the frame length as a band allocation parameter.
[0182]
When allocating with the time slot length, the following formula is used.
[0183]
Number of assigned time slots = assigned frame length / data length of one time slot
The time slot is obtained by dividing the uplink channel or the downlink channel at fixed time intervals.
[0184]
Thus, in the base station 10 of the system according to the present invention, when the total bandwidth of the data transfer request from each subscriber radio station 20 exceeds the line bandwidth, the maximum rate assigned to each subscriber radio station 20 is less than the maximum rate. In addition to the bandwidth allocation, when the total bandwidth of data transfer requests from each subscriber radio station 20 exceeds the line bandwidth, the ratio of the maximum rate assigned to each subscriber radio station 20 or the minimum rate Bandwidth allocation is performed according to the ratio.
[0185]
According to these bandwidth allocation methods, even when the total bandwidth of the data transfer request from each subscriber radio station 20 exceeds the line bandwidth, the maximum rate or the minimum rate assigned to each flow of each subscriber radio station 20 The bandwidth is allocated according to the service, etc., so that the fairness of service usage of each subscriber radio station 20 can be maintained.
In addition, the present invention is not limited to the embodiment described above and shown in the drawings, and can be implemented by being appropriately modified within a range not changing the gist thereof.
[0186]
【The invention's effect】
As described above, according to the present invention, in the subscriber radio station arranged opposite to the base station, the buffer area for storing data of the same priority is divided into a plurality of buffer areas corresponding to connection types. The buffer means is provided, and the input data having the same priority is distributed and stored in the buffer area corresponding to the connection type of the input data, and the data stored in the buffer area is set to the output rate set for each connection. Since it is output at a rate, in systems that service multiple types of information communication such as voice and images, when the network is congested, even for information communication services with severe delay and fluctuation restrictions, Delay and bandwidth fairness can be maintained.
[0187]
Moreover, according to the present invention, When the total value of the allocation request bands included in the data transfer request stored as a queue in the transfer request storage means exceeds the line band, the band allocated to each subscriber radio station of the transfer request source is assigned to each subscriber radio station. The configuration is determined according to the ratio of the maximum rate or the minimum rate allocated to the mobile station, and is assigned to each applicable subscriber radio station. Therefore, even when the total bandwidth of data transfer requests from each subscriber radio station exceeds the line bandwidth, the maximum rate assigned to each flow of each subscriber radio station Ratio or minimum rate ratio By assigning the band accordingly, it is possible to maintain the fairness of service use of each subscriber radio station.
[Brief description of the drawings]
FIG. 1 is a diagram showing an overall configuration of a wireless communication system according to the present invention.
FIG. 2 is a block diagram showing a functional configuration of a subscriber radio station.
3 is a diagram showing a configuration of a buffer 204 of a subscriber radio station in FIG.
FIG. 4 is a block diagram showing a functional configuration of a radio access processing unit of the base station.
FIG. 5 is a flowchart showing a flow of a bandwidth allocation calculation algorithm based on a first bandwidth allocation method.
FIG. 6 is a flowchart showing a flow of a bandwidth allocation calculation algorithm based on a second bandwidth allocation method.
FIG. 7 is a flowchart showing a flow of a bandwidth allocation calculation algorithm based on a third bandwidth allocation method.
FIG. 8 is a block diagram showing a functional configuration of a subscriber radio station in a conventional system.
[Explanation of symbols]
10 base stations
11 Base station indoor unit (IDU)
111 Wireless access processor
1111 and 1118 buffers
1112 MAC frame generator
1113 Error correction code addition unit
1114 Modulator
1115 Demodulator
1116 Error detection / correction section
1117 MAC frame assembly department
1119 REQ message extractor
1120 REQ message queue
1121 Bandwidth allocation calculation unit
1122 MAP message generator
113 Switch part
115 Control unit
12 Base station outdoor unit (ODU)
20, 20-1, 20-2, 20-3 subscriber radio station
200 input terminals
201 Input buffer
202 Filtering unit
203 Distribution writing part
204 buffers
2041-1, 2041-2,..., 2041-n Buffer for each type
2042 Output control unit
205 Buffer size setting section
206 Read controller
207 MAC frame generator
208 Error correction code adding unit
209 Modulator
210 Frequency converter
211 Antenna
212 Demodulator
213 Error detection / correction unit
214 MAC Frame Assembly Department
215 MAP message extractor
216 Sending timing controller
217 Output buffer
218 Output terminal
21 ODU of subscriber radio station
22 IDU of subscriber radio station
30, 30-1, 30-2, 30-3 subscriber terminal

Claims (3)

In a radio communication system comprising a base station and a plurality of subscriber radio stations that perform one-to-many radio communication with the base station,
The subscriber radio station is
A buffer means for storing data of the same priority divided into a plurality of buffer areas corresponding to connection types;
Distribution write means for distributing and storing input data of the same priority in a buffer area corresponding to the connection type of the input data;
A wireless communication system, comprising: a read control unit that outputs data stored in the buffer area at a rate of an output rate set for each connection. In a radio communication system comprising a base station and a plurality of subscriber radio stations that perform one-to-many radio communication with the base station,
The base station
Transfer request extracting means for extracting a data transfer request including an allocation request band from the received data from the subscriber radio station;
Transfer request storage means for storing a data transfer request from each subscriber radio station extracted by the transfer request extraction means as a queue ;
Bandwidth allocation calculation means for calculating a parameter value for determining a bandwidth to be allocated to each subscriber radio station of the transfer request source, including a total value of allocation request bandwidths included in the data transfer request stored in the transfer request storage means;
When the total value of the allocation request bandwidths calculated by the bandwidth allocation calculation means exceeds the line bandwidth, the bandwidth allocated to each subscriber radio station of the transfer request source is the maximum rate allocated to each subscriber radio station. Band allocation message generating means for generating a band allocation message that is determined according to the ratio of
Transmitting means for transmitting the band allocation message to a corresponding subscriber radio station, and
The subscriber radio station is
A wireless communication system comprising: a transmission timing control means for receiving the bandwidth allocation message from the base station and controlling the timing of data transmission according to the allocated bandwidth indicated by the message. In a radio communication system comprising a base station and a plurality of subscriber radio stations that perform one-to-many radio communication with the base station,
The base station
Transfer request extracting means for extracting a data transfer request including an allocation request band from the received data from the subscriber radio station;
Transfer request storage means for storing a data transfer request from each subscriber radio station extracted by the transfer request extraction means as a queue;
Bandwidth allocation calculation means for calculating a parameter value for determining a bandwidth to be allocated to each subscriber radio station of the transfer request source, including a total value of allocation request bandwidths included in the data transfer request stored in the transfer request storage means;
When the total value of the allocation request bandwidths calculated by the bandwidth allocation calculation means exceeds the line bandwidth, the bandwidth allocated to each subscriber radio station of the transfer request source is set to the minimum rate assigned to each subscriber radio station. Band allocation message generating means for generating a band allocation message that is determined according to the ratio of
Transmitting means for transmitting the band allocation message to a corresponding subscriber radio station;
Comprising
The subscriber radio station is
Transmission timing control means for receiving the bandwidth allocation message from the base station and controlling the timing of data transmission according to the allocated bandwidth indicated by the message
A wireless communication system comprising:

Images