JP4945381B2

JP4945381B2 - Base station and radio communication system

Info

Publication number: JP4945381B2
Application number: JP2007231360A
Authority: JP
Inventors: 丞小笠原; 祐輔竹道
Original assignee: Hitachi Ltd
Current assignee: Hitachi Ltd
Priority date: 2007-09-06
Filing date: 2007-09-06
Publication date: 2012-06-06
Anticipated expiration: 2027-09-06
Also published as: JP2009065435A

Description

本発明は、基地局及び無線通信システムに係り、特に、移動体通信において、基地局と移動局間で行われる通信の帯域と遅延を保証するための基地局及び無線通信システムに関する。 The present invention relates to a base station and a radio communication system, and more particularly to a base station and a radio communication system for guaranteeing a bandwidth and delay of communication performed between a base station and a mobile station in mobile communication.

従来の技術として、例えば、特開２０００−３４１３５８号公報には、基地局と移動局との間の通信品質の劣化の監視を行い、通信品質が通信良状態であるか又は劣化状態であるかを検出し、劣化状態であることを検出した場合、以降のセルにおける新たな通信を許可しないよう制御するＣＤＭＡ基地局及びその通信制御方法が記載されている。
特開２０００−３４１３５８号公報 As a conventional technique, for example, Japanese Patent Laid-Open No. 2000-341358 monitors deterioration of communication quality between a base station and a mobile station, and whether the communication quality is in a good communication state or in a deteriorated state. A CDMA base station that controls not to allow new communication in subsequent cells when it is detected that it is in a degraded state and its communication control method are described.
JP 2000-341358 A

従来では、特開２０００−３４１３５８号公報に記載されたように、基地局は、品質保証通信確認周期である移動局について、品質保証通信を行えていないことを検出した場合、品質保証を行えなくなった移動局の通信の品質保証をやめている。
本発明は、以上の点に鑑み、品質保証通信が行えなくなった場合でも、品質保証通信を継続できるようにすることを目的とする。 Conventionally, as described in Japanese Patent Application Laid-Open No. 2000-341358, when a base station detects that quality assurance communication is not being performed for a mobile station having a quality assurance communication confirmation cycle, it cannot perform quality assurance. The quality assurance of the communication of the mobile station has been stopped.
In view of the above, an object of the present invention is to allow quality assurance communication to continue even when quality assurance communication cannot be performed.

本発明の第１の解決手段によると、
複数周波数を運用している移動体通信網における基地局であって、
移動局識別子に対応して、基地局が移動局に適用している品質保証セットの識別子である適用品質保証セット識別子、移動局が通信している周波数である通信先周波数、基地局が移動局へ送信したパケットの破棄の有無を記録する呼情報管理テーブルを記憶する呼情報管理記憶部と、
品質保証セット識別子に対応して、保証帯域、許容遅延時間、優先度を含む品質保証セットを記憶する品質保証セット記憶部と、
移動局とパケットデータを送受信するために移動局とメッセージを送受信して、移動局との無線通信を制御し、基地局と接続している移動局１つにつき前記呼情報管理テーブルを１つ割り当てて、移動局の無線接続を管理する呼処理部と、
を備え、
前記呼処理部は、品質保証通信を達成しているかを一定周期で確認し、
前記呼処理部は、品質保証通信を行えていない移動局である第１の移動局を検出したら、全移動局の呼情報管理テーブルの通信先周波数を参照して、品質保証通信を行えなくなった前記第１の移動局が通信している周波数と同じ周波数で通信している移動局を通信先周波数変更候補の移動局であるひとつ又は複数の第２の移動局としてリストアップし、
前記呼処理部は、前記ひとつ又は複数の第２の移動局の前記呼情報管理テーブルの適用品質保証セット識別子に従い前記品質保証セットを参照し、遅延要因割り当て優先度については、前記品質保証セットの許容遅延時間に基づき、品質保証通信を行うために遅延に厳しい品質保証通信を行っている前記第２の移動局を優先すること、及び／又は、帯域要因割り当ての優先度については、品質保証セットの保証帯域が大きい品質保証通信を行っている前記第２の移動局を優先すること、という基準に従い、各前記第２の移動局の送信割り当て優先度を算出するものであって、前記呼処理部は、品質保証通信を行えなくなった前記第１の移動局の品質保証セットと、通信先周波数変更候補の前記第２の移動局の品質保証セットの保証帯域、許容遅延時間を参照して、品質保証を行えなくなった前記第１の移動局に対する通信先周波数変更候補の前記第２の移動局の前記送信割り当て優先度を次式に従い算出し、
送信割り当て優先度＝遅延要因割り当て優先度 × 帯域要因割り当て優先度
遅延要因割り当て優先度＝品質保証通信を出来なかった移動局の品質保証セットの許容遅延時間／リストアップした移動局の品質保証セットの許容遅延時間
帯域要因割り当て優先度＝リストアップした移動局の品質保証セットの保証帯域／品質保証通信を出来なかった移動局の品質保証セットの保証帯域

前記呼処理部は、送信割り当て優先度が最も大きい前記第２の移動局を通信先周波数変更の移動局である第３の移動局とし、
前記呼処理部は、前記第３の移動局に、前記第３の移動局が現在利用可能な周波数とその受信強度を問い合わせる周波数情報報告要求メッセージを送信し、
前記呼処理部は、移動局から受信した周波数情報報告メッセージに含まれている周波数とその受信強度を参照して、最も受信強度が大きい周波数を移動局の変更先の通信先周波数とし、
前記呼処理部は、変更先の通信先周波数を含む通信先周波数変更指示メッセージを移動局に送信する
前記基地局が提供される。 According to the first solution of the present invention,
A base station in a mobile communication network operating multiple frequencies,
Corresponding to the mobile station identifier, an applied quality assurance set identifier that is an identifier of a quality assurance set applied to the mobile station by the base station, a communication destination frequency that is a frequency with which the mobile station is communicating, and the base station is the mobile station A call information management storage unit for storing a call information management table for recording whether or not a packet transmitted to the device is discarded;
Corresponding to the quality assurance set identifier, a quality assurance set storage unit that stores a quality assurance set including a guaranteed bandwidth, an allowable delay time, and a priority;
In order to transmit / receive packet data to / from the mobile station, it transmits / receives a message to / from the mobile station, controls radio communication with the mobile station, and assigns one call information management table to each mobile station connected to the base station. A call processing unit for managing the wireless connection of the mobile station;
With
The call processing unit confirms at a certain period whether the quality assurance communication is achieved,
When the call processing unit detects the first mobile station which is a mobile station that is not performing quality assurance communication, the call processing unit cannot perform quality assurance communication with reference to the communication destination frequency in the call information management table of all mobile stations. Listing mobile stations communicating at the same frequency as the first mobile station is communicating as one or more second mobile stations that are candidate mobile station frequency change candidates,
The call processing unit refers to the quality assurance set according to an applied quality assurance set identifier of the call information management table of the one or more second mobile stations, and for delay factor allocation priority, Prioritizing the second mobile station performing quality assurance communication that is severe in delay in order to perform quality assurance communication based on the allowable delay time, and / or the priority of bandwidth factor allocation, quality assurance set Calculating the transmission allocation priority of each of the second mobile stations according to a criterion of giving priority to the second mobile station performing quality assurance communication with a large guaranteed bandwidth of the call processing, A quality assurance set of the first mobile station that is no longer able to perform quality assurance communication, and a guaranteed bandwidth of the quality assurance set of the second mobile station that is a communication destination frequency change candidate, Referring to extended time, the transmission allocation priority level of the second mobile station of the communication destination frequency change candidate for the first mobile station that no longer perform quality assurance calculated according to the following equation,
Transmission allocation priority = Delay factor allocation priority × Band factor allocation priority
Delay factor allocation priority = Allowable delay time of quality assurance set of mobile station that could not perform quality assurance communication / Allowable delay time of quality assurance set of listed mobile station
Bandwidth factor allocation priority = guaranteed bandwidth of the quality assurance set of the listed mobile station / guaranteed bandwidth of the quality assurance set of the mobile station that could not perform quality assurance communication

The call processing unit sets the second mobile station having the highest transmission allocation priority as a third mobile station that is a mobile station whose communication destination frequency is changed,
The call processing unit transmits to the third mobile station a frequency information report request message for inquiring about a frequency currently available to the third mobile station and its reception strength,
The call processing unit refers to the frequency included in the frequency information report message received from the mobile station and its reception strength, and sets the frequency with the highest reception strength as the communication destination frequency of the change destination of the mobile station,
The call processing unit is provided with the base station that transmits a communication destination frequency change instruction message including a communication destination frequency to be changed to a mobile station.

本発明の第２の解決手段によると、
複数周波数を運用している移動体通信網における基地局と、基地局との無線通信の制御と無線データ通信を行う移動局とを備えた無線通信システムであって、
前記基地局は、
移動局識別子に対応して、基地局が移動局に適用している品質保証セットの識別子である適用品質保証セット識別子、移動局が通信している周波数である通信先周波数、基地局が移動局へ送信したパケットの破棄の有無を記録する呼情報管理テーブルを記憶する呼情報管理記憶部と、
品質保証セット識別子に対応して、保証帯域、許容遅延時間、優先度を含む品質保証セットを記憶する品質保証セット記憶部と、
移動局とパケットデータを送受信するために移動局とメッセージを送受信して、移動局との無線通信を制御し、基地局と接続している移動局１つにつき前記呼情報管理テーブルを１つ割り当てて、移動局の無線接続を管理する呼処理部と、
を備え、
前記呼処理部は、品質保証通信を達成しているかを一定周期で確認し、
前記呼処理部は、品質保証通信を行えていない移動局である第１の移動局を検出したら、全移動局の呼情報管理テーブルの通信先周波数を参照して、品質保証通信を行えなくなった前記第１の移動局が通信している周波数と同じ周波数で通信している移動局を通信先周波数変更候補の移動局であるひとつ又は複数の第２の移動局としてリストアップし、
前記呼処理部は、前記ひとつ又は複数の第２の移動局の前記呼情報管理テーブルの適用品質保証セット識別子に従い前記品質保証セットを参照し、遅延要因割り当て優先度については、前記品質保証セットの許容遅延時間に基づき、品質保証通信を行うために遅延に厳しい品質保証通信を行っている前記第２の移動局を優先すること、及び／又は、帯域要因割り当ての優先度については、品質保証セットの保証帯域が大きい品質保証通信を行っている前記第２の移動局を優先すること、という基準に従い、各前記第２の移動局の送信割り当て優先度を算出するものであって、前記呼処理部は、品質保証通信を行えなくなった前記第１の移動局の品質保証セットと、通信先周波数変更候補の前記第２の移動局の品質保証セットの保証帯域、許容遅延時間を参照して、品質保証を行えなくなった前記第１の移動局に対する通信先周波数変更候補の前記第２の移動局の前記送信割り当て優先度を次式に従い算出し、
送信割り当て優先度＝遅延要因割り当て優先度 × 帯域要因割り当て優先度
遅延要因割り当て優先度＝品質保証通信を出来なかった移動局の品質保証セットの許容遅延時間／リストアップした移動局の品質保証セットの許容遅延時間
帯域要因割り当て優先度＝リストアップした移動局の品質保証セットの保証帯域／品質保証通信を出来なかった移動局の品質保証セットの保証帯域

前記呼処理部は、送信割り当て優先度が最も大きい前記第２の移動局を通信先周波数変更の移動局である第３の移動局とし、
前記呼処理部は、前記第３の移動局に、前記第３の移動局が現在利用可能な周波数とその受信強度を問い合わせる周波数情報報告要求メッセージを送信し、
前記呼処理部は、移動局から受信した周波数情報報告メッセージに含まれている周波数とその受信強度を参照して、最も受信強度が大きい周波数を移動局の変更先の通信先周波数とし、
前記呼処理部は、変更先の通信先周波数を含む通信先周波数変更指示メッセージを移動局に送信する
前記無線通信システムが提供される。 According to the second solution of the present invention,
A wireless communication system comprising a base station in a mobile communication network that operates multiple frequencies, and a mobile station that performs wireless data control and wireless communication control with the base station,
The base station
Corresponding to the mobile station identifier, an applied quality assurance set identifier that is an identifier of a quality assurance set applied to the mobile station by the base station, a communication destination frequency that is a frequency with which the mobile station is communicating, and the base station is the mobile station A call information management storage unit for storing a call information management table for recording whether or not a packet transmitted to the device is discarded;
Corresponding to the quality assurance set identifier, a quality assurance set storage unit that stores a quality assurance set including a guaranteed bandwidth, an allowable delay time, and a priority;
In order to transmit / receive packet data to / from the mobile station, it transmits / receives a message to / from the mobile station, controls radio communication with the mobile station, and assigns one call information management table to each mobile station connected to the base station. A call processing unit for managing the wireless connection of the mobile station;
With
The call processing unit confirms at a certain period whether the quality assurance communication is achieved,
When the call processing unit detects the first mobile station which is a mobile station that is not performing quality assurance communication, the call processing unit cannot perform quality assurance communication with reference to the communication destination frequency in the call information management table of all mobile stations. Listing mobile stations communicating at the same frequency as the first mobile station is communicating as one or more second mobile stations that are candidate mobile station frequency change candidates,
The call processing unit refers to the quality assurance set according to an applied quality assurance set identifier of the call information management table of the one or more second mobile stations, and for delay factor allocation priority, Prioritizing the second mobile station performing quality assurance communication that is severe in delay in order to perform quality assurance communication based on the allowable delay time, and / or the priority of bandwidth factor allocation, quality assurance set Calculating the transmission allocation priority of each of the second mobile stations according to a criterion of giving priority to the second mobile station performing quality assurance communication with a large guaranteed bandwidth of the call processing, A quality assurance set of the first mobile station that is no longer able to perform quality assurance communication, and a guaranteed bandwidth of the quality assurance set of the second mobile station that is a communication destination frequency change candidate, Referring to extended time, the transmission allocation priority level of the second mobile station of the communication destination frequency change candidate for the first mobile station that no longer perform quality assurance calculated according to the following equation,
Transmission allocation priority = Delay factor allocation priority × Band factor allocation priority
Delay factor allocation priority = Allowable delay time of quality assurance set of mobile station that could not perform quality assurance communication / Allowable delay time of quality assurance set of listed mobile station
Bandwidth factor allocation priority = guaranteed bandwidth of the quality assurance set of the listed mobile station / guaranteed bandwidth of the quality assurance set of the mobile station that could not perform quality assurance communication

The call processing unit sets the second mobile station having the highest transmission allocation priority as a third mobile station that is a mobile station whose communication destination frequency is changed,
The call processing unit transmits to the third mobile station a frequency information report request message for inquiring about a frequency currently available to the third mobile station and its reception strength,
The call processing unit refers to the frequency included in the frequency information report message received from the mobile station and its reception strength, and sets the frequency with the highest reception strength as the communication destination frequency of the change destination of the mobile station,
The wireless communication system is provided in which the call processing unit transmits a communication destination frequency change instruction message including a communication destination frequency to be changed to a mobile station.

本発明によると、品質保証通信が行えなかった移動局と同じ周波数で通信している移動局が他の周波数に移動することで、品質保証通信をおこなえなかった移動局にスロットが割り当たる機会が多くなり、品質保証通信を再び行えるようになる。また、本発明によると、通信先周波数が変わった移動局は、通信先周波数が変わる前よりも電波の受信環境が良くなり、通信先周波数を変更する前の周波数よりも１スロットで受信できるデータレートがあがるので、通信先周波数を変更する前と同等の通信が行える。 According to the present invention, a mobile station that is communicating at the same frequency as a mobile station that has not been able to perform quality assurance communication moves to another frequency, so that there is an opportunity for a slot to be allocated to a mobile station that has not been able to perform quality assurance communication. As the number increases, quality assurance communication can be performed again. In addition, according to the present invention, a mobile station whose communication destination frequency has changed has a better radio wave reception environment than before the communication destination frequency has changed, and data that can be received in one slot than the frequency before the communication destination frequency has been changed. Since the rate is increased, the same communication as before changing the communication destination frequency can be performed.

１．実施の形態１
１．１システム構成
図１に、システム構成図を示す。
一般に、移動体データ通信のひとつである１ｘＥＶＤＯでは、無線アクセス網（ＲＡＮ）は、基地局とＰＣＦ−ＳＣという装置で構成されており、図のような装置構成となっている。ＲＡＮはＰＤＳＮ（ＰａｃｋｅｔＤａｔａＳｅｒｖｉｎｇＮｏｄｅ）１１０を介して一般公衆網１１１に接続している。基地局１０４は１つ以上の周波数を運用しており、移動局１０１、１０２、１０３から上りパケットを受信したり、ＰＣＦ−ＳＣ（ＰａｃｋｅｔＣｏｎｔｒｏｌＦｕｎｃｔｉｏｎ／ＳｅｓｓｉｏｎＣｏｎｔｒｏｌ）１０９から受信した下りパケットを各移動局１０１、１０２、１０３に時分割多重で送信したりする。また基地局１０４は移動局１０１、１０２、１０３と品質保証通信を行っている場合は、保守者が基地局１０４に設定した周期で品質保証通信を行えているかを、品質保証通信を適用している移動局毎に確認している。 1. Embodiment 1
1.1 System Configuration FIG. 1 shows a system configuration diagram.
In general, in 1xEVDO, which is one of mobile data communications, a radio access network (RAN) is composed of a base station and PCF-SC devices, and has a device configuration as shown in the figure. The RAN is connected to the general public network 111 via a PDSN (Packet Data Serving Node) 110. The base station 104 operates one or more frequencies, and receives uplink packets from the mobile stations 101, 102, and 103, and each downlink packet received from a PCF-SC (Packet Control Function / Session Control) 109. It transmits to the stations 101, 102, 103 by time division multiplexing. In addition, when the base station 104 is performing quality assurance communication with the mobile stations 101, 102, 103, the quality assurance communication is applied to determine whether the quality assurance communication can be performed in the cycle set by the maintenance person in the base station 104. Check for each mobile station.

移動局１０１、１０２、１０３は基地局１０４が自移動局宛てパケットをどのくらいの送信レートで送信してほしいかを要求送信レートとして基地局１０４に通知している。基地局１０４は移動局１０１、１０２、１０３に下りパケットを送信するとき、各移動局１０１、１０２、１０３から受信した要求送信レートでパケットを送信する。ＩＰ−Ｓｗｉｔｃｈ１０８は基地局１０４、１０７やＰＣＦ−ＳＣ１０９をつなぐハブである。ＰＣＦ−ＳＣ１０９は基地局１０４、１０７の上位装置で、複数の基地局がＩＰＳｗｉｔｃｈ１０８を介してＰＣＦ−ＳＣ１０９に接続している。ＰＣＦ−ＳＣ１０９は基地局１０４、１０７から受信した移動局１０１、１０２、１０３の上りパケットをＰＤＳＮ１１０に転送したり、ＰＤＳＮ１１０から受信した移動局１０１、１０２、１０３の下りパケットを移動局１０１、１０２、１０３と無線接続している基地局１０４に転送したりする。ＰＤＳＮ１１０はＲＡＮのＧａｔｅｗａｙになっているノードで、移動局１０１、１０２、１０３のＰＰＰ接続先になっている。ＰＤＳＮ１１０はＰＣＦ−ＳＣ１０９から受信した移動局１０１、１０２、１０３の上りパケットを一般公衆網１１１を介して通信先端末１１２に転送したり、一般公衆網１１１を介して通信先端末１１２から受信した下りパケットをＰＣＦ−ＳＣ１０９に転送したりする。 The mobile stations 101, 102, and 103 notify the base station 104 as a request transmission rate of what transmission rate the base station 104 wants to transmit packets addressed to itself. When the base station 104 transmits a downlink packet to the mobile stations 101, 102, and 103, the base station 104 transmits the packet at the requested transmission rate received from each of the mobile stations 101, 102, and 103. The IP-Switch 108 is a hub that connects the base stations 104 and 107 and the PCF-SC 109. The PCF-SC 109 is a host device of the base stations 104 and 107, and a plurality of base stations are connected to the PCF-SC 109 via the IPSswitch 108. The PCF-SC 109 transfers the uplink packets of the mobile stations 101, 102, and 103 received from the base stations 104 and 107 to the PDSN 110, and the downlink packets of the mobile stations 101, 102, and 103 received from the PDSN 110 to the mobile stations 101, 102, Or to the base station 104 wirelessly connected to the mobile phone 103. The PDSN 110 is a node that is a gateway of the RAN and is a PPP connection destination of the mobile stations 101, 102, and 103. The PDSN 110 forwards the uplink packets of the mobile stations 101, 102, and 103 received from the PCF-SC 109 to the communication destination terminal 112 via the general public network 111 or the downlink received from the communication destination terminal 112 via the general public network 111. The packet is transferred to the PCF-SC 109.

図２に、移動局のソフトウェアの構成図を示す。
移動局のソフトウェア部２０１は図のような構成になっており、アプリケーションソフトウェア部２０２と基地局との無線通信の制御と無線データ通信を行う呼処理ソフトウェア部２０３を備える。アプリケーションソフトウェア部２０２は、ユーザが操作するソフトウェアで電子メールやＩＰテレビ電話などユーザアプリケーションソフトウェアを担当するブロックである。呼処理ソフトウェア２０３は、移動局と基地局の無線接続の制御とユーザアプリケーションのパケットの送受信を行うブロックである。 FIG. 2 shows a configuration diagram of software of the mobile station.
The mobile station software unit 201 is configured as shown in the figure, and includes a call processing software unit 203 that controls radio communication and radio data communication between the application software unit 202 and the base station. An application software unit 202 is software that is operated by a user, and is a block in charge of user application software such as e-mail and IP videophone. The call processing software 203 is a block that controls wireless connection between the mobile station and the base station and transmits and receives user application packets.

図３に、移動局のハードウェアの構成図を示す。
移動局のハードウェア部３０１は図のように汎用プロセッサ部３０３と共有メモリ部３０４、無線通信を行う無線通信部３０２を備える。汎用プロセッサ部３０３ではアプリケーションソフトウェア部２０２や呼処理ソフトウェア部２０３が動いている。共有メモリ部３０４には移動局のソフトウェアが稼動するための情報が格納してあり、必要に応じてアプリケーションソフトウェア部２０２や呼処理ソフトウェア部２０３が情報を引き出したり、情報を保存したりする。無線通信部３０２は移動局が利用できる周波数を探して呼処理ソフトウェア部２０３に報告したり、無線を飛ばして物理的に基地局と通信を行ったりする。 FIG. 3 shows a hardware configuration diagram of the mobile station.
As shown in the figure, the mobile station hardware unit 301 includes a general-purpose processor unit 303, a shared memory unit 304, and a wireless communication unit 302 that performs wireless communication. In the general-purpose processor unit 303, an application software unit 202 and a call processing software unit 203 are running. Information for operating the mobile station software is stored in the shared memory unit 304, and the application software unit 202 and the call processing software unit 203 extract information or save information as necessary. The radio communication unit 302 searches for a frequency that can be used by the mobile station and reports it to the call processing software unit 203, or physically communicates with the base station by skipping the radio.

図４に、基地局のソフトウェアの構成図を示す。
基地局のソフトウェア部４０１は図のように呼処理ソフトウェア部４０２を備える。呼処理ソフトウェア部４０２は、移動局とパケットデータを送受信するために、移動局と制御メッセージを送受信して、移動局との無線通信を制御する。また呼処理部ソフトェア部４０２は、他基地局や自基地局の上位装置であるＰＣＦ−ＳＣとパケットを送受信して、他ノードと通信を行う。 FIG. 4 shows a block diagram of the base station software.
The base station software section 401 includes a call processing software section 402 as shown in the figure. In order to transmit / receive packet data to / from the mobile station, the call processing software unit 402 transmits / receives control messages to / from the mobile station and controls wireless communication with the mobile station. The call processing unit software unit 402 transmits / receives a packet to / from another base station or a PCF-SC that is a host device of the own base station, and communicates with another node.

図５に、基地局のハードウェアの構成図を示す。
基地局のハードウェア部５０１は、図のように汎用プロセッサ部５０３と共有メモリ部５０４、無線通信部５０２と他ノード通信部５０５を備える。他ノード通信部５０５は基地局が他の基地局や上位ノードのＰＣＦ−ＳＣとパケットの送受信を行う。汎用プロセッサ部５０３では呼処理ソフトウェア部４０２が動いており、共有メモリ部５０４は呼処理ソフトウェア部４０２が稼動するための情報が格納してあり、必要に応じて情報を引き出したり、保存したりする。共有メモリ部５０４は、呼処理ソフトウェア部４０２で用いられる、移動局毎に呼情報管理テーブルを記憶する呼情報管理記憶部４０２１と、移動局に適用する品質保証通信を定義する品質保証セットを記憶する品質保証セット記憶部４０２２を含む。 FIG. 5 shows a hardware configuration diagram of the base station.
The hardware unit 501 of the base station includes a general-purpose processor unit 503, a shared memory unit 504, a wireless communication unit 502, and another node communication unit 505 as shown in the figure. In the other node communication unit 505, the base station transmits / receives a packet to / from another base station or a PCF-SC of an upper node. The general-purpose processor unit 503 operates the call processing software unit 402, and the shared memory unit 504 stores information for operating the call processing software unit 402, and extracts and saves information as necessary. . The shared memory unit 504 stores a call information management storage unit 4021 that stores a call information management table for each mobile station and a quality assurance set that defines quality assurance communication to be applied to the mobile station, which is used in the call processing software unit 402. A quality assurance set storage unit 4022 is included.

図６に、呼情報管理テーブルの説明図を示す。
呼情報管理記憶部４０２１に記憶される呼情報管理テーブル６０１、６０２、６０３は図のようになっており、移動局識別子、適用品質保証セット識別子、通信先周波数、要求送信レート、送信キュー管理情報が記録されている。基地局の呼処理ソフトウェア部４０２は、基地局と接続している移動局１つにつき、呼情報管理テーブルを１つ割り当てて、移動局の無線接続に関する情報を記録して、移動局の無線接続を管理している。 FIG. 6 is an explanatory diagram of the call information management table.
The call information management tables 601, 602, and 603 stored in the call information management storage unit 4021 are as shown in the figure, and are mobile station identifiers, applicable quality assurance set identifiers, communication destination frequencies, requested transmission rates, transmission queue management information. Is recorded. The call processing software unit 402 of the base station allocates one call information management table for each mobile station connected to the base station, records information about the wireless connection of the mobile station, and wirelessly connects the mobile station. Is managing.

移動局識別子は基地局が移動局を区別するための識別子である。適用品質保証セット識別子は、基地局が移動局に適用している品質保証セットの識別子である。接続先周波数は、移動局が通信している周波数である。要求送信レートは、基地局が移動局から受信した要求送信レートである。送信キュー管理情報は送信パケットに関する情報がまとめてあり、移動局へ送信したパケットの送信バイト数、送信パケット破棄の有無、送信待ちパケットの送信待ち開始時間が記録されている。送信バイト数は、基地局が品質保証確認周期の間に移動局あてに送信したパケットのバイト数である。パケットの破棄の有無は基地局が品質保証確認周期の間に、基地局が移動局に適用している品質保証セットの許容遅延時間を守れなかったためにパケットを破棄したかどうかを記録している。送信待ち開始時間は、送信待ちパケットが送信キューにつまれた時間を記録している。 The mobile station identifier is an identifier for the base station to distinguish mobile stations. The applied quality assurance set identifier is an identifier of a quality assurance set applied by the base station to the mobile station. The connection destination frequency is a frequency with which the mobile station is communicating. The request transmission rate is a request transmission rate received by the base station from the mobile station. In the transmission queue management information, information on transmission packets is collected, and the number of transmission bytes of packets transmitted to the mobile station, the presence / absence of transmission packet discard, and the transmission waiting start time of transmission waiting packets are recorded. The number of transmitted bytes is the number of bytes of a packet transmitted from the base station to the mobile station during the quality assurance check period. Whether or not the packet is discarded records whether or not the packet was discarded during the quality assurance check cycle because the base station failed to comply with the allowable delay time of the quality assurance set applied to the mobile station. . The transmission waiting start time records the time when the transmission waiting packet is stuck in the transmission queue.

図では、例えば、移動局識別子が「２」の移動局に呼情報管理テーブル６０２を割り当てており、適用している品質保証セット識別子は７０２、通信先周波数は８００ＭＨｚ、要求送信レートは３８．４ｋｂｐｓ、送信バイト数は６４ｂｙｔｅ、パケットの破棄はないこと、送信キューの１番目のパケットは、２００７／０３／１６の１２：００：００：０２０に発生していることが記録されている。 In the figure, for example, a call information management table 602 is assigned to a mobile station with a mobile station identifier “2”, the applied quality assurance set identifier is 702, the communication destination frequency is 800 MHz, and the required transmission rate is 38.4 kbps. The number of transmitted bytes is 64 bytes, the packet is not discarded, and the first packet in the transmission queue is recorded to occur at 12: 00: 00: 00 on 2007/03/16.

図７に、品質保証セットの説明図を示す。
品質保証セット記憶部４０２２に記憶された品質保証セットは、図のようになっており、品質保証セット識別子、保証帯域、許容遅延時間、優先度を含む。品質保証セット７０１０の場合、品質保証セット識別子が７０１で、品質保証セット７０１０に定義されている通信を行う場合は、移動局は品質保証セット識別子を「７０１」で指定して、品質保証設定要求を行う。品質保証セット７０１０の保証帯域は、２５６ｋｂｐｓで、基地局が移動局に品質保証セット７０１０の品質保証通信を行う場合、２５６ｋｂｐｓのトラフィックを送信することを定義している。品質保証セット７０１０の許容遅延帯域は、１５０ｍｓｅｃで、基地局が移動局に品質保証セット７０１０の品質保証通信を行う場合、１５０ｍｓｅｃ以上の遅延を発生させないでパケットを送信することを定義している。品質保証セット７０１０の優先度は１で、基地局が移動局に品質保証セット７０１０の品質保証通信を行う場合、優先度が２である品質保証セット７０２０を適用している移動局よりも、優先して品質保証通信を行うことを定義している。 FIG. 7 is an explanatory diagram of the quality assurance set.
The quality assurance set stored in the quality assurance set storage unit 4022 is as shown in the figure, and includes a quality assurance set identifier, a guaranteed bandwidth, an allowable delay time, and a priority. In the case of the quality assurance set 7010, when the quality assurance set identifier is 701 and communication defined in the quality assurance set 7010 is performed, the mobile station designates the quality assurance set identifier as “701” and requests quality assurance setting. I do. The guaranteed bandwidth of the quality assurance set 7010 is 256 kbps, and it is defined that when the base station performs quality assurance communication of the quality assurance set 7010 to the mobile station, traffic of 256 kbps is transmitted. The allowable delay band of the quality assurance set 7010 is 150 msec. When the base station performs quality assurance communication of the quality assurance set 7010 to the mobile station, it is defined that the packet is transmitted without causing a delay of 150 msec or more. The priority of the quality assurance set 7010 is 1, and when the base station performs quality assurance communication of the quality assurance set 7010 to the mobile station, the priority is higher than the mobile station to which the quality assurance set 7020 having the priority 2 is applied. To perform quality assurance communication.

１．２品質保証通信
以下に、基地局の呼処理ソフトウェア部４０２による品質保証通信の処理について説明する。
基地局がパケットを送信する時間の区切りをスロット（ｓｌｏｔ）とよび、スロット毎に送信するパケットを切り替える。基地局の呼処理ソフトウェア部４０２はある移動局あての送信パケット送信する場合、送信パケットを先入先出で共有メモリ部５０４にある移動局の送信キューに積む。基地局の呼処理ソフトウェア部４０２はパケットを送信キューにつむとき、パケットを送信キューにつんだ時間を送信待ち開始時間として、送信パケットが発生した移動局の呼情報管理テーブル４０２１の送信キュー管理情報にある送信待ち開始時間に記録する。 1.2 Quality Assurance Communication The following describes quality assurance communication processing by the call processing software unit 402 of the base station.
The time interval at which the base station transmits a packet is called a slot, and the packet to be transmitted is switched for each slot. When transmitting a transmission packet addressed to a certain mobile station, the call processing software unit 402 of the base station loads the transmission packet in the transmission queue of the mobile station in the shared memory unit 504 in a first-in first-out manner. When the call processing software unit 402 of the base station picks up the packet in the transmission queue, the transmission queue management information in the call information management table 4021 of the mobile station in which the transmission packet is generated is defined as the transmission waiting start time. Record at the transmission start time at

基地局の呼処理ソフトウェア部４０２は、スロットが切り替わるときに各移動局の送信キューにつまれているパケットの送信優先度を算出して、移動局毎に最も送信優先度が高いパケットを探し、スロット割り当て候補パケットとする。基地局の呼処理ソフトウェア部４０２は各移動局のスロット割り当て候補パケットの中で、最も送信優先度が高いスロット割り当て候補パケットにスロットを割り当てて、パケットを送信する。 The call processing software unit 402 of the base station calculates the transmission priority of the packet held in the transmission queue of each mobile station when the slot is switched, and searches for the packet having the highest transmission priority for each mobile station, Let it be a slot allocation candidate packet. The call processing software unit 402 of the base station allocates a slot to the slot allocation candidate packet having the highest transmission priority among the slot allocation candidate packets of each mobile station, and transmits the packet.

基地局の呼処理ソフトウェア部４０２は、移動局に適用している品質保証セットに定義されている許容遅延時間内にあるパケットであるかを送信キューの先頭パケットから順番に確認し、許容遅延時間内のパケットであれば、そのパケットを移動局のスロット割り当て候補パケットとし、そのパケットの送信優先度を算出する。 The call processing software unit 402 of the base station checks in order from the first packet in the transmission queue whether the packet is within the allowable delay time defined in the quality assurance set applied to the mobile station. If the packet is within the range, the packet is used as a slot allocation candidate packet of the mobile station, and the transmission priority of the packet is calculated.

基地局の呼処理ソフトウェア部４０２は、送信キューにあるパケットについて、そのパケットが許容遅延時間内のパケットであるかどうかを判断する。例えば、呼処理ソフトウェア部４０２は、現在時刻から送信キュー管理情報にある送信待ち開始時間を引いてパケットの送信遅延時間を算出し、送信遅延時間が移動局に適用されている適用品質保証セット識別子に対応して品質保証セットに定義されている許容遅延時間を求め、送信遅延時間が許容遅延時間より小さい値になっているか大きい値になっているかで、許容遅延時間内か否かを判断する。呼処理ソフトウェア部４０２は、もし送信遅延時間が許容遅延時間より大きいパケットであれば、基地局の呼処理ソフトウェア部４０２はそのパケットを送信キューから破棄し、送信キュー管理情報の該当するパケットに関する情報の初期化と、該当する呼情報管理テーブルにパケット破棄の有無に「有」の記録を行い、次に送信予定のパケットについて許容遅延時間内にあるかを確認する。もし送信遅延時間が許容遅延時間より小さなパケットであれば、スロット割り当て候補パケットとする。 The call processing software unit 402 of the base station determines whether or not the packet in the transmission queue is within the allowable delay time. For example, the call processing software unit 402 calculates the packet transmission delay time by subtracting the transmission wait start time in the transmission queue management information from the current time, and applies the quality assurance set identifier applied to the mobile station. The allowable delay time defined in the quality assurance set is obtained in response to, and whether the transmission delay time is smaller or larger than the allowable delay time is determined. . If the transmission delay time is larger than the allowable delay time, the call processing software unit 402 discards the packet from the transmission queue, and information on the corresponding packet in the transmission queue management information. And “Yes” is recorded in the corresponding call information management table as to whether or not the packet is discarded, and it is confirmed whether the packet scheduled to be transmitted is within the allowable delay time. If the transmission delay time is smaller than the allowable delay time, it is determined as a slot allocation candidate packet.

基地局呼処理ソフトウェア部４０２は、呼情報管理テーブル４０２１と共有メモリ部５０４上にある保守者が設定した品質保証通信確認周期を使って、各移動局のスロット割り当て候補パケットの送信優先度を遅延度と帯域保証度、適用品質保証セットの優先度を以下の式から算出する。

送信優先度＝遅延度×帯域保証度／品質保証セットの優先度

遅延度＝（現在時刻−送信待ち開始時間）／品質保証セットの許容遅延時間
帯域保証度＝（品質保証セットの保証帯域−現在の送信帯域）／品質保証セットの保証帯域
現在の送信帯域＝８×送信バイト数／品質保証通信確認周期
The base station call processing software unit 402 delays the transmission priority of the slot allocation candidate packet of each mobile station using the call information management table 4021 and the quality assurance communication confirmation period set by the maintainer on the shared memory unit 504. The degree of bandwidth, the degree of bandwidth guarantee, and the priority of the applied quality guarantee set are calculated from the following equations.

Transmission priority = Delay degree x Bandwidth guarantee / Quality guarantee set priority

Degree of delay = (current time−transmission waiting start time) / allowable delay time bandwidth guarantee level of quality assurance set = (guaranteed bandwidth of quality assurance set−current transmission bandwidth) / guaranteed bandwidth of quality assurance set current transmission bandwidth = 8 × Number of bytes sent / Quality assurance communication check cycle

基地局の呼処理ソフトウェア部４０２は、各移動局のスロット割り当て候補パケットの中で、送信優先度が一番大きいスロット割り当て候補パケットにスロットを割り当てて、パケットを送信する。もし一番高い送信優先度のスロット割り当て候補パケットをもつ移動局が複数存在した場合は、基地局の呼処理ソフトウェア部４０２は移動局から受信している移動局の要求送信レートが一番高い移動局のスロット割り当て候補パケットにスロットを割り当てて送信する。 The call processing software unit 402 of the base station allocates a slot to the slot allocation candidate packet having the highest transmission priority among the slot allocation candidate packets of each mobile station, and transmits the packet. If there are a plurality of mobile stations having slot allocation candidate packets with the highest transmission priority, the call processing software unit 402 of the base station moves with the highest requested transmission rate of the mobile station received from the mobile station. A slot is allocated to a station slot allocation candidate packet and transmitted.

基地局の呼処理ソフトウェア部４０２は、品質保証通信確認周期に定められている周期で、現在の送信帯域と品質保証セットの保証帯域の大小比較することで品質保証セットの保証帯域が守られているかを各移動局について確認する。基地局の呼処理ソフトウェア部４０２は、もし現在の送信帯域が品質保証セットの保証帯域より小さければ、基地局の呼処理ソフトウェア部４０２は、品質保証通信が行えていないことを検出する。 The call processing software unit 402 of the base station compares the current transmission band and the guaranteed band of the quality assurance set with the size of the guaranteed band of the quality assurance set at a period determined by the quality assurance communication confirmation period. Check for each mobile station. If the current transmission bandwidth is smaller than the guaranteed bandwidth of the quality assurance set, the call processing software portion 402 of the base station detects that the quality assurance communication is not being performed.

基地局の呼処理ソフトウェア部４０２は、送信キュー管理情報のパケット破棄の有無を参照することで、品質保証セットの許容遅延時間が守られているかを確認する。もしパケット破棄の有無が有となっていれば、基地局の呼処理ソフトウェア部４０２は、品質保証通信が行えていないことを検出する。 The call processing software unit 402 of the base station confirms whether the allowable delay time of the quality assurance set is observed by referring to the presence or absence of packet discard in the transmission queue management information. If the presence or absence of packet discard is present, the call processing software unit 402 of the base station detects that quality assurance communication is not being performed.

基地局の呼処理ソフトウェア部４０２は品質保証通信を行えていないことの検出をすべての移動局について行った後、すべての移動局の送信キュー管理テーブルについて、送信バイト数をゼロ、パケット破棄の有無を無にする。 After the call processing software unit 402 of the base station detects that the quality assurance communication cannot be performed for all mobile stations, the number of transmission bytes is zero for the transmission queue management table of all mobile stations, and whether or not the packet is discarded. Make no.

図８に、品質保証通信についてのシーケンス図を示す。
移動局が品質保証通信を行うとき、図のようにして品質保証通信を始める。
移動局識別子が１の移動局のアプリケーションソフトウェア部２０２が品質保証通信を必要とするアプリケーションを立ち上げたとき（図８の８０７）、アプリケーションソフトウェア部２０２が立ち上げたアプリケーションが必要としている通信品質が定められた品質保証セット識別子７０１を移動局の呼処理ソフトウェア部２０３に通知する（図８の８０８）。 FIG. 8 shows a sequence diagram for quality assurance communication.
When the mobile station performs quality assurance communication, it starts quality assurance communication as shown in the figure.
When the application software unit 202 of the mobile station whose mobile station identifier is 1 launches an application that requires quality assurance communication (807 in FIG. 8), the communication quality required by the application launched by the application software unit 202 is The determined quality assurance set identifier 701 is notified to the call processing software unit 203 of the mobile station (808 in FIG. 8).

移動局の呼処理ソフトウェア部２０３は移動局のアプリケーションソフトウェア部２０２から通知された品質保証セット識別子７０１が入った、品質保証通信設定要求メッセージを作成する（図８の８０９）。移動局の呼処理ソフトウェア部２０３は、移動局の無線通信部３０２を介して品質保証通信設定要求メッセージを基地局に送り（図８の８１０、８１１）、品質保証通信の設定要求を基地局に行う。 The call processing software unit 203 of the mobile station creates a quality assurance communication setting request message containing the quality assurance set identifier 701 notified from the application software unit 202 of the mobile station (809 in FIG. 8). The call processing software unit 203 of the mobile station sends a quality assurance communication setting request message to the base station via the wireless communication unit 302 of the mobile station (810 and 811 in FIG. 8), and sends a quality assurance communication setting request to the base station. Do.

基地局の無線通信部５０２は、移動局から受信した品質保証通信設定要求メッセージを受信したら、基地局の呼処理ソフトウェア部４０２に品質保証通信設定要求メッセージを転送する（図８の８１２）。基地局の呼処理ソフトウェア部４０２は、移動局から受信した品質保証通信設定要求メッセージを解析して、移動局から要求されている品質保証セット識別子が７０１であることを知り、共有メモリ部５０４の品質保証セット記憶部４０２２から移動局が指定した品質保証セット識別子７０１をもつ品質保証セット７０１０を読み込む（図８の８１３）。さらに、呼処理ソフトウェア部４０２は、移動局の移動局識別子を受信メッセージから抽出し（あるいは適宜割当て）、移動局に対して呼情報管理テーブルを割り当てる。この例では、移動局識別子が「１」の移動局に、呼情報管理テーブル６０１を割り当てている。 When receiving the quality assurance communication setting request message received from the mobile station, the wireless communication unit 502 of the base station transfers the quality assurance communication setting request message to the call processing software unit 402 of the base station (812 in FIG. 8). The call processing software unit 402 of the base station analyzes the quality assurance communication setting request message received from the mobile station, knows that the quality assurance set identifier requested from the mobile station is 701, and the shared memory unit 504 The quality assurance set 7010 having the quality assurance set identifier 701 designated by the mobile station is read from the quality assurance set storage unit 4022 (813 in FIG. 8). Furthermore, the call processing software unit 402 extracts (or assigns as appropriate) the mobile station identifier of the mobile station from the received message, and assigns a call information management table to the mobile station. In this example, the call information management table 601 is assigned to the mobile station with the mobile station identifier “1”.

基地局の呼処理ソフトウェア部４０２は、品質保証セット識別子７０１の品質保証セット７０１０を共有メモリ部５０４の品質保証セット記憶部４０２２から読み込めたら、移動局から受信した品質保証セット７０１を受理、適用したとして、移動局の呼情報管理テーブル（この例では移動局識別子が「１」の呼情報管理テーブル６０１）の適用品質保証セット識別子に、移動局から要求された品質保証セット識別子７０１を記録する。 When the call processing software unit 402 of the base station reads the quality assurance set 7010 of the quality assurance set identifier 701 from the quality assurance set storage unit 4022 of the shared memory unit 504, it accepts and applies the quality assurance set 701 received from the mobile station. The quality assurance set identifier 701 requested from the mobile station is recorded in the applicable quality assurance set identifier of the mobile station call information management table (call information management table 601 with the mobile station identifier “1” in this example).

基地局の呼処理ソフトウェア部４０２は、移動局に適用した品質保証セット識別子７０１が入っている品質保証通信設定結果メッセージを生成して、基地局の無線通信部５０２を介して移動局に品質保証通信設定結果メッセージを返却する（図８の８１４、８１５）。 The call processing software unit 402 of the base station generates a quality assurance communication setting result message including the quality assurance set identifier 701 applied to the mobile station, and performs quality assurance to the mobile station via the radio communication unit 502 of the base station. The communication setting result message is returned (814 and 815 in FIG. 8).

基地局から品質保証通信設定結果メッセージを受信した移動局の無線通信部３０２は、品質保証通信設定結果メッセージを移動局の呼処理ソフトウェア部２０３に転送する（図８の８１６）。
移動局の呼処理ソフトウェア部２０３は基地局から受信した品質保証通信設定結果メッセージを解析し、品質保証通信設定結果メッセージに含まれている品質保証セット識別子７０１が、品質保証通信設定要求メッセージに含まれている品質保証セット識別子であるかを確認し、両識別子が同じであればアプリケーションソフトウェア部２０２に品質保証通信適用を通知する（図８の８１７、７１８）。 The wireless communication unit 302 of the mobile station that has received the quality assurance communication setting result message from the base station transfers the quality assurance communication setting result message to the call processing software unit 203 of the mobile station (816 in FIG. 8).
The call processing software unit 203 of the mobile station analyzes the quality assurance communication setting result message received from the base station, and the quality assurance set identifier 701 included in the quality assurance communication setting result message is included in the quality assurance communication setting request message. If the identifiers are the same, the application software unit 202 is notified of the application of quality assurance communication (817 and 718 in FIG. 8).

１．３帯域・遅延保証
本実施の形態では、品質保証を行えなかった移動局の存在を基地局の呼処理ソフトウェア部４０２が検出したら、品質保証通信を行えなくなった移動局と同じ周波数で通信している移動局から、最もスロット割り当て優先度が高い移動局を選び、その移動局が基地局からの電波を最もよく受信できる周波数に通信先周波数を変更させる。 1.3 Bandwidth / Delay Guarantee In this embodiment, when the call processing software unit 402 of the base station detects the presence of a mobile station that cannot perform quality assurance, communication is performed at the same frequency as the mobile station that cannot perform quality assurance communication. The mobile station having the highest slot allocation priority is selected from the mobile stations being operated, and the communication destination frequency is changed to a frequency at which the mobile station can best receive radio waves from the base station.

以下に、基地局の呼処理ソフトウェア部による処理を説明する。
図９は、基地局が行う通信先周波数変更移動局を選別する処理のフローチャートである。また、図１０は、移動局の通信先周波数変更についてのシーケンス図である。 Hereinafter, processing by the call processing software unit of the base station will be described.
FIG. 9 is a flowchart of processing for selecting a communication destination frequency change mobile station performed by the base station. FIG. 10 is a sequence diagram for changing the communication destination frequency of the mobile station.

品質保証通信を達成しているかを確認するために、基地局の呼処理ソフトウェア部１００１は各移動局の呼情報管理テーブルの適用品質保証セット識別子を参照して、移動局に適用している品質保証セットの優先度が高い品質保証通信を行っている移動局から、適用品質保証セットに定義されている保証帯域と許容遅延時間が守られているかを一定周期で確認する（図９の９０２、図１０の１００９）。 In order to confirm whether or not the quality assurance communication is achieved, the call processing software unit 1001 of the base station refers to the applied quality assurance set identifier in the call information management table of each mobile station, and the quality applied to the mobile station Whether or not the guaranteed bandwidth and the allowable delay time defined in the applicable quality assurance set are being observed from a mobile station performing quality assurance communication with a high priority of the assurance set is confirmed (902 in FIG. 9). 1009 in FIG.

具体的には、例えば、基地局の呼処理ソフトウェア部１００１は、移動局識別子に従い各移動局の呼情報管理テーブルを参照し、品質保証セットに定義されている遅延が守られているかを、移動局の送信キュー管理情報のパケット破棄の有無から確認し、パケット破棄が有であれば、品質保証通信ができていなかったと判断する。あるいは、呼処理ソフトウェア部１００１は、移動局識別子に従い各移動局の呼情報管理テーブルを参照し、適用品質保証セット識別子に従い、品質保証セット識別子に従い品質保証セット記憶部を参照し、移動局の品質保証セットに定義されている保証帯域が守られているかを現在の送信帯域と保証帯域の大小比較を行い、保証帯域が送信帯域よりも大きい場合、品質保証通信ができなかったと判断する。これら両者の判断のいずれか一方、または、両方により判断してもよい。図１０の例では、基地局の呼処理ソフトウェア１００１が、移動局識別子１の移動局の品質保証通信を行えなくなったと判断している。 Specifically, for example, the call processing software unit 1001 of the base station refers to the call information management table of each mobile station according to the mobile station identifier, and determines whether the delay defined in the quality assurance set is observed. It is confirmed from the presence or absence of packet discard in the transmission queue management information of the station, and if packet discard is present, it is determined that quality assurance communication has not been performed. Alternatively, the call processing software unit 1001 refers to the call information management table of each mobile station according to the mobile station identifier, refers to the quality assurance set storage unit according to the applicable quality assurance set identifier, and refers to the quality assurance set storage unit according to the quality assurance set identifier. Whether the guaranteed bandwidth defined in the guaranteed set is protected is compared between the current transmission bandwidth and the guaranteed bandwidth. If the guaranteed bandwidth is larger than the transmission bandwidth, it is determined that the quality assurance communication could not be performed. You may judge by either one of these both judgments, or both. In the example of FIG. 10, the call processing software 1001 of the base station determines that the quality assurance communication of the mobile station with the mobile station identifier 1 can no longer be performed.

基地局の呼処理ソフトウェア部１００１が品質保証通信を行えなかった移動局の存在を検出したら（図９の９０３、図１０の１０１０）、全移動局の呼情報管理テーブルの通信先周波数を参照して、品質保証通信を行えなくなった移動局が通信している周波数と同じ周波数で通信している移動局を通信先周波数変更候補移動局としてリストアップし（図９の９０４、図１０の１０１１）、各通信先周波数変更候補移動局のスロット割り当て優先度を算出して（図９の９０５、図１０の１０１２）、通信先周波数変更移動局を選択する（図９の９０６、図１０の１０１２）。 When the call processing software unit 1001 of the base station detects the presence of a mobile station that has not been able to perform quality assurance communication (903 in FIG. 9 and 1010 in FIG. 10), it refers to the communication destination frequency in the call information management table of all mobile stations. Thus, the mobile stations that are communicating at the same frequency as the frequency at which the mobile station that cannot perform the quality assurance communication is listed as the communication destination frequency change candidate mobile stations (904 in FIG. 9, 1011 in FIG. 10). Then, the slot allocation priority of each communication destination frequency change candidate mobile station is calculated (905 in FIG. 9, 1012 in FIG. 10), and the communication destination frequency change mobile station is selected (906 in FIG. 9, 1012 in FIG. 10). .

具体的には、例えば、基地局の呼処理ソフトウェア部１００１は、品質保証通信を行えなくなった移動局の品質保証セットと、通信先周波数変更候補移動局の品質保証セットの保証帯域、許容遅延時間を参照して、品質保証を行えなくなった移動局に対する各通信先周波数変更候補移動局のスロット割り当て優先度を以下のようにして算出する。

スロット割り当て優先度＝遅延要因割り当て優先度 × 帯域要因割り当て優先度

遅延要因割り当て優先度＝品質保証通信を出来なかった移動局の品質保証セットの許容遅延時間／リストアップした移動局の品質保証セットの許容遅延時間

帯域要因割り当て優先度＝リストアップした移動局の品質保証セットの保証帯域／品質保証通信を出来なかった移動局の品質保証セットの保証帯域
Specifically, for example, the call processing software unit 1001 of the base station, the quality assurance set of the mobile station that can no longer perform quality assurance communication, the guaranteed bandwidth and the allowable delay time of the quality assurance set of the communication destination frequency change candidate mobile station Referring to, the slot allocation priority of each communication destination frequency change candidate mobile station for the mobile station that cannot perform quality assurance is calculated as follows.

Slot allocation priority = Delay factor allocation priority × Band factor allocation priority

Delay factor allocation priority = Allowable delay time of quality assurance set of mobile station that could not perform quality assurance communication / Allowable delay time of quality assurance set of listed mobile station

Bandwidth factor allocation priority = guaranteed bandwidth of the quality assurance set of the listed mobile station / guaranteed bandwidth of the quality assurance set of the mobile station that could not perform quality assurance communication

基地局の呼処理ソフトウェア部１００１は、品質保証通信を行うために、遅延に厳しい品質保証通信を行っている移動局に優先してスロットを割り当てる。遅延要因割り当て優先度は、品質保証通信を出来なかった移動局の品質保証セットの許容遅延時間を、通信先周波数変更候補移動局の品質保証セットの許容遅延時間で割ることで計算する。遅延要因割り当て優先度は、通信先周波数変更候補移動局の品質保証セットの許容遅延時間が、品質保証できなかった移動局の品質保証セットの許容遅延時間に対して、どのくらいの割合だけ遅延に厳しいかを算出することで、遅延に関して通信先周波数変更候補移動局は、品質保証できなかった移動局に対してどのぐらいの割合で優先的にスロットを割り当てられるかを算出する。 In order to perform quality assurance communication, the call processing software unit 1001 of the base station assigns a slot preferentially to a mobile station performing quality assurance communication that is severe in delay. The delay factor allocation priority is calculated by dividing the allowable delay time of the quality assurance set of the mobile station that could not perform quality assurance communication by the allowable delay time of the quality assurance set of the communication destination frequency change candidate mobile station. The delay factor allocation priority is limited to how much the allowable delay time of the quality assurance set of the mobile station frequency change candidate mobile station can be delayed relative to the allowable delay time of the quality assurance set of the mobile station whose quality could not be guaranteed. By calculating the above, regarding the delay, the communication destination frequency change candidate mobile station calculates how much the slot can be preferentially assigned to the mobile station whose quality could not be guaranteed.

基地局の呼処理ソフトウェア部１００１は、品質保証セットの保証帯域が大きい品質保証通信をおこなっている移動局にスロットを割り当てる。帯域要因割り当て優先度は、通信先周波数変更候補移動局の品質保証セットの保証帯域を、品質保証通信できなかった移動局の品質保証セットの保証帯域で割ることで計算する。帯域要因割り当て優先度は、通信先周波数変更候補移動局の品質保証セットの保証帯域が、品質保証できなかった移動局の品質保証セットの保証帯域に対して、どのくらいの割合でたくさんスロットを割り当てなければならないかを算出することで、保証帯域に関して通信先周波数変更候補移動局は、品質保証できなかった移動局に関して、どのくらいの割合で優先的にスロットを割り当てられるかを算出する。 The call processing software unit 1001 of the base station allocates slots to mobile stations performing quality assurance communication with a large guaranteed bandwidth of the quality assurance set. The bandwidth factor allocation priority is calculated by dividing the guaranteed bandwidth of the quality assurance set of the mobile frequency change candidate mobile station by the guaranteed bandwidth of the quality assurance set of the mobile station that could not perform quality assurance communication. The bandwidth factor allocation priority must be set so that the guaranteed bandwidth of the quality assurance set of the target frequency change candidate mobile station must be allocated as many slots as the percentage of the guaranteed bandwidth of the quality assurance set of the mobile station whose quality could not be guaranteed. By calculating whether or not it is necessary, the communication destination frequency change candidate mobile station with respect to the guaranteed bandwidth calculates the percentage of slots that can be preferentially allocated with respect to the mobile station that could not guarantee the quality.

そして、基地局は各通信先周波数変更候補移動局のスロット割り当て優先度を算出したら、スロット割り当て優先度が最も大きい移動局を通信先周波数変更移動局とする（図９の９０６、図１０の１０１２）。図１０の１０１２の例では基地局の呼処理ソフトウェア部１００１は、移動局識別子２の移動局を通信先周波数変更移動局としている。 When the base station calculates the slot allocation priority of each communication destination frequency change candidate mobile station, the mobile station with the highest slot allocation priority is set as the communication destination frequency change mobile station (906 in FIG. 9, 1012 in FIG. 10). ). In the example of 1012 in FIG. 10, the call processing software unit 1001 of the base station uses the mobile station with the mobile station identifier 2 as the communication destination frequency change mobile station.

次に、基地局の呼処理ソフトウェア部１００１は、通信先周波数変更移動局の呼処理ソフトウェア部１００６に、通信先周波数変更移動局が現在利用できる周波数とその受信強度を問い合わせる、周波数情報報告要求メッセージを送信する（図９の９０７、図１０の１０１３）。 Next, the call processing software unit 1001 of the base station inquires of the call processing software unit 1006 of the communication destination frequency change mobile station about the frequency currently available to the communication destination frequency change mobile station and its reception strength, and a frequency information report request message. Is transmitted (907 in FIG. 9 and 1013 in FIG. 10).

基地局の呼処理ソフトウェア部１００１から、周波数情報報告要求メッセージを受信した移動局の呼処理ソフトウェア部１００６は、移動局が利用できる周波数とその受信強度を調べるために、移動局の無線通信部１００５に移動局が受信できる周波数の探索とその受信強度の測定を依頼する（図１０の１０１４）。移動局の無線通信部１００５は、自移動局が受信できる周波数をチューニングして、移動局が利用できる周波数の探索を行い、それぞれの周波数の受信強度を測定する（図１０の１０１５）。移動局の無線通信部１００５は、移動局の呼処理ソフトウェア部１００６に、移動局が受信できた周波数とその受信強度を報告する（図１０の１０１６）。移動局の呼処理ソフトウェア部１００６は、移動局の無線通信部から報告を受けた移動局の無線通信部１００５が受信できた周波数とその受信強度を移動局が現在利用できる周波数情報とし、この情報を周波数情報報告メッセージにのせて、基地局の呼処理ソフトウェア部１００６に周波数情報報告メッセージを送信する（図１０の１０１７）。 Upon receiving the frequency information report request message from the call processing software unit 1001 of the base station, the call processing software unit 1006 of the mobile station checks the frequency that can be used by the mobile station and its reception strength, and the radio communication unit 1005 of the mobile station Is requested to search for a frequency that can be received by the mobile station and to measure the received intensity (1014 in FIG. 10). The radio communication unit 1005 of the mobile station tunes frequencies that can be received by the mobile station, searches for frequencies that can be used by the mobile station, and measures the reception intensity of each frequency (1015 in FIG. 10). The radio communication unit 1005 of the mobile station reports to the call processing software unit 1006 of the mobile station the frequency that the mobile station has received and its reception strength (1016 in FIG. 10). The mobile station call processing software unit 1006 uses the frequency received by the radio communication unit 1005 of the mobile station and the reception intensity received from the radio communication unit of the mobile station as frequency information that can be used by the mobile station. Is put on the frequency information report message, and the frequency information report message is transmitted to the call processing software unit 1006 of the base station (1017 in FIG. 10).

基地局の呼処理ソフトウェア部１００１は、移動局の呼処理ソフトウェア部１００６から受信した周波数情報報告メッセージに含まれている周波数とその受信強度を参照して、最も受信強度が大きい周波数を移動局の通信先周波数変更先とする（図９の９０８、図１０の１０１７、１０１８）。図１０の例では、周波数２を通信先周波数変更先としている。 The call processing software unit 1001 of the base station refers to the frequency included in the frequency information report message received from the call processing software unit 1006 of the mobile station and its reception strength, and determines the frequency with the highest reception strength of the mobile station. The communication destination frequency is changed (908 in FIG. 9 and 1017 and 1018 in FIG. 10). In the example of FIG. 10, the frequency 2 is the communication destination frequency change destination.

基地局の呼処理ソフトウェア部１００１は、移動先周波数を通信先周波数変更指示メッセージに含めて、通信先周波数変更指示メッセージを移動局の呼処理ソフトウェア部１００６に送信する（図９の９０８、図１０の１０１９）。 The call processing software unit 1001 of the base station includes the destination frequency in the communication destination frequency change instruction message and transmits the communication destination frequency change instruction message to the call processing software unit 1006 of the mobile station (908 in FIG. 9, FIG. 10). 1019).

基地局から通信先周波数変更指示メッセージを受信した移動局の呼処理ソフトウェア部１００６は、通信先周波数変更指示メッセージに含まれている周波数に通信先周波数を変更するように移動局の無線通信部１００５に依頼する（図１０の１０２０）。移動局の無線通信部１００５は、通信先周波数を、移動局の呼処理ソフトウェア部１００６から通知された移動先周波数に変更して、通信先周波数の変更完了通知を移動局の呼処理ソフトウェア部１００６に通知する（図１０の１０２２）。 Upon receiving the communication destination frequency change instruction message from the base station, the call processing software unit 1006 of the mobile station changes the communication destination frequency to the frequency included in the communication destination frequency change instruction message. (1020 in FIG. 10). The radio communication unit 1005 of the mobile station changes the communication destination frequency to the movement destination frequency notified from the call processing software unit 1006 of the mobile station, and notifies the mobile station call processing software unit 1006 of the completion of change of the communication destination frequency. (1022 in FIG. 10).

移動局の呼処理ソフトウェア部１００６は、移動局の無線通信部１００５から通信先周波数の変更完了通知を受信したら、移動局の呼処理ソフトウェア部１００６は、基地局の呼処理ソフトウェア部１００１に通信先周波数変更完了通知メッセージを送信し、基地局の呼処理ソフトウェア部１００１は移動局から受信した通信先周波数変更完了通知メッセージを受理する（図１０の１０２３）。 When the call processing software unit 1006 of the mobile station receives the change completion notification of the communication destination frequency from the radio communication unit 1005 of the mobile station, the call processing software unit 1006 of the mobile station communicates with the call processing software unit 1001 of the base station. The frequency change completion notification message is transmitted, and the call processing software unit 1001 of the base station receives the communication destination frequency change completion notification message received from the mobile station (1023 in FIG. 10).

２．他の実施の形態
以下の各実施の形態２、３、４は、実施の形態１の図９のステップ９０４の変形例であり、通信先周波数変更候補移動局をリストアップする手法がそれぞれ異なる。その他の処理は、「１．２品質保証通信」、特に、図９のフローチャート、図１０のシーケンス図及びそれらの説明箇所で示したものと同様である。また、実施の形態２、３、４の「システム構成」及び「帯域・遅延保証」に関しても、実施の形態１の「１．１システム構成」及び「１．３帯域・遅延保証」と同様である。 2. Other Embodiments Each of the following second, third, and fourth embodiments is a modification of step 904 in FIG. 9 of the first embodiment, and the method for listing communication destination frequency change candidate mobile stations is different. Other processes are the same as those described in “1.2 Quality Assurance Communication”, in particular, the flowchart in FIG. 9, the sequence diagram in FIG. 10, and the description thereof. The “system configuration” and “bandwidth / delay guarantee” in the second, third, and fourth embodiments are the same as the “1.1 system configuration” and “1.3 band / delay guarantee” in the first embodiment. is there.

（１）実施の形態２
上述の実施の形態では、図９のフローチャートのように基地局の呼処理ソフトウェア部が、品質保証通信確認周期にて、各移動局に適用している品質保証通信の達成を、移動局に適用している品質保証セットの優先度が高い移動局から、移動局の呼情報管理テーブル、送信キュー管理情報、適用品質保証セットから確認する（図９の９０２）。基地局の呼処理ソフトウェア部が品質保証通信を行えていない移動局を検出したら（図９の９０３）、呼処理ソフトウェア部は、通信先周波数変更候補移動局として、品質保証通信が行えなくなった移動局の品質保証セットに定義されている優先度より低い優先度の品質保証セットが適用されている移動局を通信先周波数変更候補移動局としてリストアップする（図９の９０４に相当する変形例）。以後の処理は図９のフローチャートのステップ９０５以降と同様になる。 (1) Embodiment 2
In the above-described embodiment, the call processing software unit of the base station applies the achievement of quality assurance communication applied to each mobile station in the quality assurance communication confirmation cycle to the mobile station as shown in the flowchart of FIG. The mobile station having the highest quality assurance set priority is confirmed from the call information management table, transmission queue management information, and applied quality assurance set of the mobile station (902 in FIG. 9). When the call processing software unit of the base station detects a mobile station that is not performing quality assurance communication (903 in FIG. 9), the call processing software unit moves as a communication destination frequency change candidate mobile station and cannot perform quality assurance communication. A mobile station to which a quality assurance set having a priority lower than the priority defined in the quality assurance set of the station is applied is listed as a communication destination frequency change candidate mobile station (variation corresponding to 904 in FIG. 9). . The subsequent processing is the same as that after step 905 in the flowchart of FIG.

（２）実施の形態３
実施の形態１では、図９のフローチャートのように基地局の呼処理ソフトウェア部が、品質保証通信確認周期にて、各移動局に適用している品質保証通信の達成を、移動局に適用している品質保証セットの優先度が高い移動局から、移動局の呼情報管理テーブル、送信キュー管理情報、適用品質保証セットから確認する（図９の９０２）。基地局の呼処理ソフトウェア部が品質保証通信を行えていない移動局を検出したら（図９の９０３）、呼処理ソフトウェア部は、通信先周波数変更候補移動局として、品質保証通信が行えなくなった移動局の品質保証セットに定義されている優先度と同じ優先度の品質保証セットが適用されている移動局を通信先周波数変更候補移動局としてリストアップする（図９の９０４に相当する変形例）。以後の処理は図９のフローチャートのステップ９０５以降と同様になる。 (2) Embodiment 3
In the first embodiment, as shown in the flowchart of FIG. 9, the call processing software unit of the base station applies the achievement of the quality assurance communication applied to each mobile station to the mobile station in the quality assurance communication confirmation cycle. The mobile station with the highest priority of the quality assurance set is confirmed from the call information management table, transmission queue management information, and applied quality assurance set of the mobile station (902 in FIG. 9). When the call processing software unit of the base station detects a mobile station that is not performing quality assurance communication (903 in FIG. 9), the call processing software unit moves as a communication destination frequency change candidate mobile station and cannot perform quality assurance communication. A mobile station to which a quality assurance set having the same priority as that defined in the station quality assurance set is applied is listed as a communication destination frequency change candidate mobile station (variation corresponding to 904 in FIG. 9). . The subsequent processing is the same as that after step 905 in the flowchart of FIG.

（３）実施の形態４
実施の形態１では、図９のフローチャートのように基地局の呼処理ソフトウェア部が、品質保証通信確認周期にて、各移動局に適用している品質保証通信の達成を、移動局に適用している品質保証セットの優先度が高い移動局から、移動局の呼情報管理テーブル、送信キュー管理情報、適用品質保証セットから確認する（図９の９０２）。基地局の呼処理ソフトウェア部が品質保証通信を行えていない移動局を検出したら（図９の９０３）、呼処理ソフトウェア部は、通信先周波数変更候補移動局として、品質保証通信が行えなくなった移動局の品質保証セットに定義されている優先度よりも高い優先度の品質保証セットが適用されている移動局を通信先周波数変更候補移動局としてリストアップする（図９の９０４に相当する変形例）。以後の処理は図９のフローチャートのステップ９０５以降と同様になる。 (3) Embodiment 4
In the first embodiment, as shown in the flowchart of FIG. 9, the call processing software unit of the base station applies the achievement of the quality assurance communication applied to each mobile station to the mobile station in the quality assurance communication confirmation cycle. The mobile station with the highest priority of the quality assurance set is confirmed from the call information management table, transmission queue management information, and applied quality assurance set of the mobile station (902 in FIG. 9). When the call processing software unit of the base station detects a mobile station that is not performing quality assurance communication (903 in FIG. 9), the call processing software unit moves as a communication destination frequency change candidate mobile station and cannot perform quality assurance communication. A mobile station to which a quality assurance set having a priority higher than the priority defined in the station quality assurance set is applied is listed as a communication destination frequency change candidate mobile station (a modification corresponding to 904 in FIG. 9). ). The subsequent processing is the same as that after step 905 in the flowchart of FIG.

本発明は、１ｘＥＶＤＯに限らず、各種の方式を採用する基地局及び無線通信システムに適用することができる。 The present invention is not limited to 1xEVDO, but can be applied to base stations and wireless communication systems that employ various methods.

システム構成図。System Configuration. 移動局のソフトウェアの構成図。The block diagram of the software of a mobile station. 移動局のハードウェアの構成図。The block diagram of the hardware of a mobile station. 基地局のソフトウェアの構成図。The block diagram of the base station software. 基地局のハードウェアの構成図。The block diagram of the hardware of a base station. 呼情報管理テーブルの説明図。Explanatory drawing of a call information management table. 品質保証セットの説明図。Explanatory drawing of a quality assurance set. 品質保証通信についてのシーケンス図。The sequence diagram about quality assurance communication. 基地局が行う通信先周波数変更移動局を選別する処理のフローチャート。The flowchart of the process which selects the communication destination frequency change mobile station which a base station performs. 移動局の通信先周波数変更についてのシーケンス図。The sequence diagram about the communication destination frequency change of a mobile station.

Explanation of symbols

１０１、１０２、１０３移動局
１０４基地局
１０５、１０６周波数
１０７基地局
１０８ＩＰ−Ｓｗｉｔｃｈ
１０９ＰＣＦ−ＳＣ
１１０ＰＤＳＮ
１１１一般公衆網
１１２通信先端末
101, 102, 103 Mobile station 104 Base station 105, 106 Frequency 107 Base station 108 IP-Switch
109 PCF-SC
110 PDSN
111 General public network 112 Destination terminal

Claims

A base station in a mobile communication network operating multiple frequencies,
Corresponding to the mobile station identifier, an applied quality assurance set identifier that is an identifier of a quality assurance set applied to the mobile station by the base station, a communication destination frequency that is a frequency with which the mobile station is communicating, and the base station is the mobile station A call information management storage unit for storing a call information management table for recording whether or not a packet transmitted to the device is discarded;
Corresponding to the quality assurance set identifier, a quality assurance set storage unit that stores a quality assurance set including a guaranteed bandwidth, an allowable delay time, and a priority;
In order to transmit / receive packet data to / from the mobile station, it transmits / receives a message to / from the mobile station, controls radio communication with the mobile station, and assigns one call information management table to each mobile station connected to the base station. A call processing unit for managing the wireless connection of the mobile station;
With
The call processing unit confirms at a certain period whether the quality assurance communication is achieved,
When the call processing unit detects the first mobile station which is a mobile station that is not performing quality assurance communication, the call processing unit cannot perform quality assurance communication with reference to the communication destination frequency in the call information management table of all mobile stations. Listing mobile stations communicating at the same frequency as the first mobile station is communicating as one or more second mobile stations that are candidate mobile station frequency change candidates,
The call processing unit refers to the quality assurance set according to an applied quality assurance set identifier of the call information management table of the one or more second mobile stations, and for delay factor allocation priority, Prioritizing the second mobile station performing quality assurance communication that is severe in delay in order to perform quality assurance communication based on the allowable delay time, and / or the priority of bandwidth factor allocation, quality assurance set Calculating the transmission allocation priority of each of the second mobile stations according to a criterion of giving priority to the second mobile station performing quality assurance communication with a large guaranteed bandwidth of the call processing, A quality assurance set of the first mobile station that is no longer able to perform quality assurance communication, and a guaranteed bandwidth of the quality assurance set of the second mobile station that is a communication destination frequency change candidate, Referring to extended time, the transmission allocation priority level of the second mobile station of the communication destination frequency change candidate for the first mobile station that no longer perform quality assurance calculated according to the following equation,
Transmission allocation priority = Delay factor allocation priority × Band factor allocation priority
Delay factor allocation priority = Allowable delay time of quality assurance set of mobile station that could not perform quality assurance communication / Allowable delay time of quality assurance set of listed mobile station
Bandwidth factor allocation priority = guaranteed bandwidth of the quality assurance set of the listed mobile station / guaranteed bandwidth of the quality assurance set of the mobile station that could not perform quality assurance communication

The call processing unit sets the second mobile station having the highest transmission allocation priority as a third mobile station that is a mobile station whose communication destination frequency is changed,
The call processing unit transmits to the third mobile station a frequency information report request message for inquiring about a frequency currently available to the third mobile station and its reception strength,
The call processing unit refers to the frequency included in the frequency information report message received from the mobile station and its reception strength, and sets the frequency with the highest reception strength as the communication destination frequency of the change destination of the mobile station,
The call processing unit transmits the communication destination frequency change instruction message including the change destination communication destination frequency to the mobile station.

A wireless communication system comprising a base station in a mobile communication network that operates multiple frequencies, and a mobile station that performs wireless data control and wireless communication control with the base station,
The base station
Corresponding to the mobile station identifier, an applied quality assurance set identifier that is an identifier of a quality assurance set applied to the mobile station by the base station, a communication destination frequency that is a frequency with which the mobile station is communicating, and the base station is the mobile station A call information management storage unit for storing a call information management table for recording whether or not a packet transmitted to the device is discarded;
Corresponding to the quality assurance set identifier, a quality assurance set storage unit that stores a quality assurance set including a guaranteed bandwidth, an allowable delay time, and a priority;
In order to transmit / receive packet data to / from the mobile station, it transmits / receives a message to / from the mobile station, controls radio communication with the mobile station, and assigns one call information management table to each mobile station connected to the base station. A call processing unit for managing the wireless connection of the mobile station;
With
The call processing unit confirms at a certain period whether the quality assurance communication is achieved,
When the call processing unit detects the first mobile station which is a mobile station that is not performing quality assurance communication, the call processing unit cannot perform quality assurance communication with reference to the communication destination frequency in the call information management table of all mobile stations. Listing mobile stations communicating at the same frequency as the first mobile station is communicating as one or more second mobile stations that are candidate mobile station frequency change candidates,
The call processing unit refers to the quality assurance set according to an applied quality assurance set identifier of the call information management table of the one or more second mobile stations, and for delay factor allocation priority, Prioritizing the second mobile station performing quality assurance communication that is severe in delay in order to perform quality assurance communication based on the allowable delay time, and / or the priority of bandwidth factor allocation, quality assurance set Calculating the transmission allocation priority of each of the second mobile stations according to a criterion of giving priority to the second mobile station performing quality assurance communication with a large guaranteed bandwidth of the call processing, A quality assurance set of the first mobile station that is no longer able to perform quality assurance communication, and a guaranteed bandwidth of the quality assurance set of the second mobile station that is a communication destination frequency change candidate, Referring to extended time, the transmission allocation priority level of the second mobile station of the communication destination frequency change candidate for the first mobile station that no longer perform quality assurance calculated according to the following equation,
Transmission allocation priority = Delay factor allocation priority × Band factor allocation priority
Delay factor allocation priority = Allowable delay time of quality assurance set of mobile station that could not perform quality assurance communication / Allowable delay time of quality assurance set of listed mobile station
Bandwidth factor allocation priority = guaranteed bandwidth of the quality assurance set of the listed mobile station / guaranteed bandwidth of the quality assurance set of the mobile station that could not perform quality assurance communication

The call processing unit sets the second mobile station having the highest transmission allocation priority as a third mobile station that is a mobile station whose communication destination frequency is changed,
The call processing unit transmits to the third mobile station a frequency information report request message for inquiring about a frequency currently available to the third mobile station and its reception strength,
The call processing unit refers to the frequency included in the frequency information report message received from the mobile station and its reception strength, and sets the frequency with the highest reception strength as the communication destination frequency of the change destination of the mobile station,
The wireless communication system, wherein the call processing unit transmits a communication destination frequency change instruction message including a communication destination frequency of a change destination to a mobile station.

The call processing unit is a mobile station that communicates at the same frequency as the frequency that the first mobile station that is unable to perform quality assurance communication when performing the listing, and the first The quality assurance set is referenced according to the applied quality assurance set identifier of the call information management table of the mobile station, and a quality assurance set having a priority lower than the priority defined in the quality assurance set of the first mobile station is applied. The base station according to claim 1 or the wireless communication system according to claim 2, wherein the mobile station is listed as one or a plurality of second mobile stations as communication destination frequency change candidates.

The call processing unit is a mobile station that communicates at the same frequency as the frequency that the first mobile station that is unable to perform quality assurance communication when performing the listing, and the first The quality assurance set is referenced according to the applied quality assurance set identifier of the call information management table of the mobile station, and the quality assurance set having the same priority as the priority defined in the quality assurance set of the first mobile station is applied. The base station according to claim 1 or the wireless communication system according to claim 2, wherein the mobile station is listed as one or a plurality of second mobile stations as communication destination frequency change candidates.

The call processing unit is a mobile station that communicates at the same frequency as the frequency that the first mobile station that is unable to perform quality assurance communication when performing the listing, and the first The quality assurance set is referred to according to the applied quality assurance set identifier of the call information management table of the mobile station, and a quality assurance set having a priority higher than the priority defined in the quality assurance set of the first mobile station is applied. The base station according to claim 1 or the wireless communication system according to claim 2, wherein the mobile station is listed as one or a plurality of second mobile stations as communication destination frequency change candidates.

2. The call processing unit according to claim 1, wherein if the packet is discarded, the call processing unit determines from the packet discard data in the call information management table of the mobile station that the quality assurance communication has not been performed. A base station or a wireless communication system according to claim 2.

The call processing unit compares the current transmission band with the guaranteed band defined in the quality assurance set of the mobile station, and determines that quality assurance communication could not be performed when the guaranteed band is larger than the transmission band. The base station according to claim 1 or the wireless communication system according to claim 2.

The delay factor allocation priority is calculated by dividing the allowable delay time of the quality assurance set of the mobile station that could not perform quality assurance communication by the allowable delay time of the quality assurance set of the communication destination frequency change candidate mobile station. The base station according to claim 1, or the wireless communication system according to claim 2.

The bandwidth factor allocation priority is calculated by dividing a guaranteed bandwidth of a quality assurance set of a mobile station to which a frequency change can be made by a communication destination by a guaranteed bandwidth of a quality assurance set of a mobile station that could not perform quality assurance communication. The base station according to claim 1 or the wireless communication system according to claim 2.

The mobile station that has received the frequency information report request message from the base station checks the frequency that can be used by the mobile station and its reception strength,
The radio communication system according to claim 2, wherein the mobile station transmits a frequency information report message including the received frequency and the received intensity to the base station.

The mobile station that has received the communication destination frequency change instruction message from the base station changes the communication destination frequency to the frequency included in the communication destination frequency change instruction message, and the mobile station notifies the base station of the communication destination frequency change completion notification message. The wireless communication system according to claim 2, which transmits