JP4540880B2

JP4540880B2 - Mobile communication system, mobile communication terminal of mobile communication system, and base station

Info

Publication number: JP4540880B2
Application number: JP2001157138A
Authority: JP
Inventors: 克彦清水
Original assignee: Kyocera Corp
Current assignee: Kyocera Corp
Priority date: 2001-05-25
Filing date: 2001-05-25
Publication date: 2010-09-08
Anticipated expiration: 2021-05-25
Also published as: JP2002353876A

Abstract

PROBLEM TO BE SOLVED: To provide a mobile communication terminal and a base station in a mobile communication system where a user can make data communication in an excellent reception state. SOLUTION: The mobile communication transmission terminal 1 has its own position detection function, transmits position information of its own station to base stations (2-1, 2-2, 2-3, etc.), at a prescribed frequency of transmission and also a notice request of fluctuation prediction information of a downlink data communication speed, the base stations receive the notice request, calculate the fluctuation prediction information of the downlink data communication speed on the basis of the position information received from the mobile communication terminal 1 and mobile information calculated from the position information at a present point of time, inform the mobile communication terminal 1 about the fluctuation prediction information, and the mobile communication terminal 1 receives the fluctuation prediction information and displays the fluctuation prediction information on a display section.

Description

【０００１】
【発明の属する技術分野】
本発明は、Cdma2000 1x-EV DO方式（またはHDR方式）等の、基地局から移動端末への方向（下り方向）の通信速度（データレート）が移動端末における基地局信号（パイロットチャネル信号など）の受信状態（受信電界強度、搬送波対干渉比=ＣＩＲ）により大きく変化するよう制御される移動通信システムでの移動端末ユーザーヘの下り方向データレート変動予測情報の通知機能に関する。
【０００２】
【従来の技術】
近年、次世代の高速無線通信方式としてcdma2000 1x-EV DO方式が開発されている。
上記cdma2000 1x-EV DO方式は、Qualcomm社によるcdma2000 1xの拡張方式であるHDR（High Data Rate）方式を標準化した方式として、電波産業界ARIBにおいてStd.T-64 1S-2000 C.S.0024“cdma2000 High Rate Packet Data Air Interface Specification"で標準化されているもので、現在国内ではKDDI社によりサービスされているcdmaOne方式（国内ではARIB T-53、北米、韓国等ではEIA/TIA/IS-95等）を拡張し、第３世代方式（３Ｇ）に対応させたcdma2000 1x方式を更にデータ通信に特化して通信速度を改善することを目的とした方式である。
なお、cdma2000 lx-EV DOにおいて、EVはEvolution、DOはData onlyの意である。
【０００３】
cdma2000 1x-EV DO方式では、携帯通信端末から受信した受信状態を通知する情報に基づいて、基地局が当該端末へ送信するデータの変調方式を切り替えることにより、当該端末の受信状態が良好な時は誤り耐性が低いが高速な通信レート、受信状態が悪いときは低速だが誤り耐性の高い通信レートを使用することが可能となる。
【０００４】
また、cdma2000 1x-EV DO方式の下り方向（基地局から携帯通信端末への方向）では、時間を1/600秒単位で分割し、その時間内では一つの携帯通信端末だけとの通信を行い、通信相手の携帯通信端末を時間により切り替えることにより複数の携帯通信端末と通信を行う、時分割多重アクセス（TDMA；time division multiplex access）を採用している。これにより、常に、個々の携帯通信端末に対して最大の電力を持ってデータ送信を行うことが可能となり、携帯通信端末間で行うデータ通信を最速の通信速度で行うことができる。
【０００５】
【発明が解決しようとする課題】
一方、上述したcdma2000 1x-EV DO方式は、基地局から携帯通信端末への方向のデータ通信速度が携帯通信端末における受信状態（例えば受信電界強度、搬送波対干渉比=ＣＩＲ）によって、大きく変化するという特性を有している。
例えば、携帯通信端末において、その受信状態が最も良好なときであれば通信速度2.4Mbpsでのデータ通信が可能となるが、受信状態が悪いときでは数10kbps程度にまでデータ通信速度が低下してしまう。そして、携帯通信端末での受信状態が悪く、低い下りデータ通信速度しか得られないような状況で比較的大きな容量のデータのダウンロードを開始してしまうと、以下に示すような問題が生じる。
【０００６】
まず、第1に、データダウンロード終了までに長い時間要するため、利用者はその間、時間を束縛されることとなり、十分なサービスを行える環境を提供することができない。
第２に、通信時間が長くなるため通信費が高額になってしまう。
第３に、ダウンロードを行っている期間は、ＣＰＵ（中央処理装置）処理能力の一部がデータ通信の処理に割かれることになり、キー入力等の利用者操作に対する反応が遅くなる。
【０００７】
第４に、ＲＦ部を有する携帯通信端末の消費電流はＲＦ部での消費電流が支配的であり、ＲＦ部での消費電流はデータ通信速度よりもＲＦ部が起動している時間に大きく左右されるため、低いデータ通信速度で長時間データ通信を行うことは高いデータ通信速度で短時間に行う場合に比べ、電流の消費が大きくなってしまう。
第５に、通信網側から携帯通信端末へ動画データや音楽データをダウンロードしながら、端末での再生も並行して行う（動画や音楽のストリーミング再生）ようなサービスを受ける場合には、所定値以上の下りデータ通信速度が必要とされるが、この時、必要とされる下りデータ通信速度が得られない場合には、画質、音質の低下や動画停止、音の途切れ等の影響が考えられ、十分なサービス品質が得られない。
【０００８】
本発明は、このような事情に鑑みてなされたもので、場所に応じて顕著に変化する受信状態を即時的かつ正確に利用者に通知することにより、利用者が良好な受信状態でデータ通信を行うことができる、移動通信システムの携帯通信端末及び基地局を提供することを目的とする。
【０００９】
【課題を解決するための手段】
上記目的を達成するために、請求項１に記載の発明は、基地局から携帯通信端末への下り方向のデータ通信速度が、該携帯通信端末における基地局信号の受信状態により大きく変化するように制御される移動通信システムにおいて、前記携帯通信端末は、自局の位置検出機能を有し、自局の位置情報を所定の頻度で基地局に送出し、かつ下り方向データ通信速度の変動予測情報の通知要求を送出し、前記基地局は、前記通知要求を受信し、前記携帯通信端末から受信した位置情報、及び該位置情報から算出した移動情報に基づいて現時点から所定時間内の下り方向データ通信速度の変動予測情報を算出し、該変動予測情報を前記携帯通信端末に通知すると共に、前記携帯通信端末は、前記変動予測情報を受信し、該変動予測情報を表示手段に表示することを特徴とする。
【００１０】
また、請求項２に記載の発明は、基地局から携帯通信端末への下り方向のデータ通信速度が、該携帯通信端末における基地局信号の受信状態により大きく変化するように制御される移動通信システムの携帯通信端末において、前記携帯通信端末は、自局の位置検出機能を有し、自局の位置情報を所定の頻度で基地局に送出し、かつ下り方向データ通信速度の変動予測情報の通知要求を送出すると共に、前記基地局により算出された下り方向データ通信速度の変動予測情報を受信し、該変動予測情報を表示手段に表示することを特徴とする。
【００１１】
また、請求項３に記載の発明は、基地局から携帯通信端末への下り方向のデータ通信速度が、該携帯通信端末における基地局信号の受信状態により大きく変化するように制御される移動通信システムの基地局において、前記基地局は、前記携帯通信端末より下り方向データ通信速度の変動予測情報の通知要求を受信し、前記携帯通信端末から受信した位置情報、及び該位置情報から算出した移動情報に基づいて現時点から所定時間内の下り方向データ通信速度の変動予測情報を算出し、該変動予測情報を前記携帯通信端末に通知することを特徴とする。
【００１２】
また、請求項４に記載の発明は、基地局から携帯通信端末への下り方向のデータ通信速度が、該携帯通信端末における基地局信号の受信状態により大きく変化するように制御される移動通信システムの携帯通信端末において、前記携帯通信端末は、自局の位置検出機能を有し、自局の位置情報及び移動情報を所定の頻度で基地局に送出し、かつ下り方向データ通信速度の変動予測情報の通知要求を送出すると共に、前記基地局により算出された下り方向データ通信速度の変動予測情報を受信し、該変動予測情報を表示手段に表示することを特徴とする。
【００１３】
また、請求項５に記載の発明は、基地局から携帯通信端末への下り方向のデータ通信速度が、該携帯通信端末における基地局信号の受信状態により大きく変化するように制御される移動通信システムの基地局において、前記基地局は、前記携帯通信端末より下り方向データ通信速度の変動予測情報の通知要求を受信し、前記携帯通信端末から受信した位置情報及び移動情報に基づいて現時点から所定時間内の下り方向データ通信速度の変動予測情報を算出し、該変動予測情報を前記携帯通信端末に通知することを特徴とする。
【００１４】
また、請求項６に記載の発明は、基地局から携帯通信端末への下り方向のデータ通信速度が、該携帯通信端末における基地局信号の受信状態により大きく変化するように制御される移動通信システムの携帯通信端末において、各種設定、指示を行うための操作手段と、自局の位置を検出する位置検出手段と、各種データを表示する表示手段と、前記位置検出手段の検出出力を取り込み、自局の位置情報を所定の頻度で基地局に送出し、かつ前記操作手段の操作に基づいて下り方向データ通信速度の変動予測情報の通知要求を送出すると共に、前記基地局により算出された下り方向データ通信速度の変動予測情報を受信し、該変動予測情報を前記表示手段に表示する制御手段とを有することを特徴とする。
【００１５】
また、請求項７に記載の発明は、基地局から携帯通信端末への下り方向のデータ通信速度が、該携帯通信端末における基地局信号の受信状態により大きく変化するように制御される移動通信システムの基地局において、前記携帯通信端末より所定の頻度で受信した該携帯通信端末の位置情報を記憶する記憶手段と、前記記憶手段に記憶されている位置情報に基づいて前記携帯通信端末の移動情報を算出する移動情報検出手段と、前記携帯通信端末より下り方向データ通信速度の変動予測情報の通知要求を受信し、前記記憶手段に記憶されている位置情報、及び該位置情報から前記移動情報検出手段により算出した移動情報に基づいて現時点から所定時間内の下り方向データ通信速度の変動予測情報を算出し、該変動予測情報を前記携帯通信端末に通知する制御手段とを有することを特徴とする。
【００１６】
また、請求項８に記載の発明は、基地局から携帯通信端末への下り方向のデータ通信速度が、該携帯通信端末における基地局信号の受信状態により大きく変化するように制御される移動通信システムの携帯通信端末において、各種設定、指示を行うための操作手段と、自局の位置を検出する位置検出手段と、前記位置検出手段により検出された位置情報を記憶する記憶手段と、各種データを表示する表示手段と、前記記憶手段に記憶された位置情報に基づいて自局の移動情報を算出し、自局の位置情報及び移動情報を所定の頻度で基地局に送出し、前記操作手段の操作に基づいて下り方向データ通信速度の変動予測情報の通知要求を送出すると共に、前記基地局により算出された下り方向データ通信速度の変動予測情報を受信し、該変動予測情報を前記表示手段に表示する制御手段とを有することを特徴とする。
【００１７】
また、請求項９に記載の発明は、基地局から携帯通信端末への下り方向のデータ通信速度が、該携帯通信端末における基地局信号の受信状態により大きく変化するように制御される移動通信システムの基地局において、所定の頻度で携帯通信端末より受信した該携帯通信端末の位置情報及び移動情報を記憶する記憶手段と、前記携帯通信端末より下り方向データ通信速度の変動予測情報の通知要求を受信し、前記記憶手段に記憶されている位置情報及び移動情報に基づいて現時点から所定時間内の下り方向データ通信速度の変動予測情報を算出し、該変動予測情報を前記携帯通信端末に通知する制御手段とを有することを特徴とする。
【００１８】
本発明によれば、携帯通信端末のユーザは、データ通信を開始する前に、現時点からある時間内の下り方向データ通信速度の変動予測情報を確認することができる。この結果、携帯通信端末のユーザは、予想外の長時間ダウンロードを回避できる確率が高くなり、長い時間ダウンロードの終了を待つストレスから開放される可能性が高くなる。
また、高い下りデータレートが得られる受信状態を選択してデータ通信（データダウンロード）を行うことにより、基地局設備（能力）の効率的な利用が可能となる。
【００１９】
さらに、高い下りデータレートが得られる受信状態を選択してデータ通信（データダウンロード）を行うことにより、データダウンロード時間の短縮が可能となる。この結果、ユーザがキー入力等の操作を行ったときに、操作感が悪化する可能性（CPU処理能力の一部がデータ通信処理に割かれることに起因するもの）が低減される。
【００２０】
また、携帯電話などRF部分を有する携帯通信端末の消費電流はRF部分での消費電流が支配的であり、RF部分での消費電流はデータ通信速度よりもRF部が起動している時間に大きく左右されるが、データダウンロード時間の短縮により消費電流の削減が可能となる。
回線交換での時間課金を前提とした湯合には、データダウンロード時間の短縮により料金の低減が可能となる。
【００２１】
【発明の実施の形態】
以下、本発明の実施の形態を、図面を参照して詳細に説明する。本発明の実施の形態に係る移動通信システムの構成を図１に示す。同図において、本実施の形態に係る移動通信システムは、携帯通信端末１と、基地局２−１、２−２、２−３、…と、基地局２−１、２−２、２−３、…を統括的に制御する制御局３とを有している。制御局３は、ルータ４を介してインターネット等のネットワーク５に接続されている。この移動通信システムでは、基地局から携帯通信端末への下り方向のデータ通信速度が、該携帯通信端末における基地局信号の受信状態により大きく変化するように制御される。
【００２２】
上記構成において、携帯通信端末１は、自局の位置検出機能を有し、自局の位置情報を所定の頻度で自局が位置するサービスエリアを管轄する基地局、例えば、基地局２−１に送出し、かつ下り方向データ通信速度の変動予測情報の通知要求を送出する。（以下、基地局については基地局２−１を例にとり、説明するが、他の基地局の構成、動作は、基地局２−１と同様であることは勿論である。）
一方、基地局２−１は、前記通知要求を受信し、携帯通信端末１から受信した位置情報、及び該位置情報から算出した移動情報に基づいて現時点から所定時間内の下り方向データ通信速度の変動予測情報を算出し、該変動予測情報を携帯通信端末１に通知する。携帯通信端末１は、前記変動予測情報を受信し、該変動予測情報を表示手段に表示する。
【００２３】
次に、携帯通信端末１の構成を図２に示す。図２は、本発明の一実施形態に係るcdma2000 1x-EV DO方式を採用した携帯通信端末１の構成を示している。
図２に示すように、本実施形態に係る携帯通信端末１は、アンテナ１００、共用器１０１、復調器１０２、変調器１０８からなるＲＦ部と、復号器１０３、符号化器１０７からなるベースバンド処理部と、自局の位置検出を行う位置検出手段としてのＧＰＳ受信部１０５、ＣＰＵ１０４、メモリ１０９、液晶ディスプレイ等からなる表示部１１０、キーパッド、キーボード等の操作部１１１を備えている。
【００２４】
また、当該携帯通信端末１を無線モデムとして使用できるように、パーソナルコンピュータ（ＰＣ）１１３との外部インタフェース（例えばシリアルポート、パラレルポート、ＵＳＢ、blue-tooth、赤外線通信、１０base-T LAN等）１１２を備えている。
【００２５】
復調器１０２は、基地局、例えば、基地局２−１から受信した受信信号の変調方式に対応する復調方式によって、ベースバンド帯域の受信信号から多重化信号を復調する。なお、本実施形態においては、ＱＰＳＫ（quadriphase phase shift keying）、８ＰＳＫ（８ phase shift keying）、１６ＱＡＭ（１６quadrature amplitude modulation）の３種のいずれかの復調方式によって復調を行う。復調器１０２によって復調された受信データは、復号器１０３によって復号処理される。即ち、復号器１０３はスペクトル拡散されている受信多重化信号をスペクトル逆拡散する。
【００２６】
ここで、自局に割り当てられた受信データ（例えば、ダウンロードを希望したデータ等）があった場合には、受信データは復号器１０３からＣＰＵ１０４へ出力される。この受信データは、ＣＰＵ１０４内において処理されるか、又はＣＰＵ１０４及び外部インタフェース１１２を経由して外部のＰＣ等１１３へ送られるようになっている。
【００２７】
ＣＰＵ９は、当該携帯通信端末において生成された、又は、外部のＰＣ等２９から外部インタフェース２７を経由して入力された送信データがあるか否かを判断し、送信データがある場合には、この送信データを符号化器１７に出力する。この送信データは、符号化器１７によって更に符号化され、変調器１９によって特定の変調方式（例えば、ＱＰＳＫ）により変調され、共用器３及びアンテナ１を経由して基地局へ送信されるようになっている。
【００２８】
次に、基地局２−１は、アンテナ２００、受信部２０１、送信部２０２、制御部２０３、制御局とのインタフェースを行うネットワークインタフェース（Ｉ／Ｆ）部２０４、携帯通信端末での下り方向データ通信速度の変動予測情報を算出する変動予測演算部２０５とを有している。
受信部２０１は携帯通信端末からの送信データを受信し、送信部２０２は、携帯通信端末への送信データを送出する機能を有する。
【００２９】
また、変動予測演算部２０５は、位置情報記憶部２０５１、移動情報検出部２０５２、ＤＲＣマップ記憶部２０５３、ＤＲＣ変動予測部２０５４を有している。
位置情報記憶部２０５１は、携帯通信端末１から送信される位置情報（例えば、経度、緯度情報）を記憶する記憶装置である。また、移動情報検出部２０５２は、位置情報記憶部２０５１から読み出した携帯通信端末１の位置情報から携帯通信端末１の移動方向、移動速度を検出する機能を有する。
【００３０】
ＤＲＣマップ記憶部２０５３は、ＤＲＣ（Data Rate Control Bit）マップを有する記憶装置である。ＤＲＣとは、本来、移動端末から基地局へ通知される移動端末で測定された下り方向の受信状態から期待される「所定の誤り率以下で受信可能な最高伝送速度」を意味するものであるが、本実施の形態では自局サービスエリア内における場所毎の下り方向予測データ通信速度値として使用している。
【００３１】
ここで、ＤＲＣマップは、予め自局サービスエリア内における場所毎の受信電波状況（基地局から携帯通信端末１に出力される下りパイロット信号のＣＩＲ（搬送波対干渉比）を測定し求められた典型的なＣＩＲ値のマップを図４に示すＣＩＲ−ＤＲＣ変換テーブルを用いてＤＲＣ値のマップに変換したものである。因みにＣＩＲは、次式により算出される。
ＣＩＲ=(Ec/lo)/(１-Ec/lo)…（１）
なお、Ec/Ioはパイロット信号強度対全受信信号強度を示す。
【００３２】
ＤＲＣ変動予測部２０５４は、携帯通信端末１の下り方向データ通信速度の変動予測情報であるＤＲＣ変動予測情報を算出する。
制御部２０３は、スケジューラ２０３０を含んで構成され、各部を制御する。スケジューラ２０３０は、現在データ通信中の携帯通信端末に対して時分割単位ごとにどの携帯通信端末と通信を行うかのスケジューリングを行う。
【００３３】
上記構成からなる本実施の形態に係る移動通信システムの動作を図５乃至図８のフローチャートを参照して説明する。図５は携帯通信端末１及び基地局２−１の動作を、図６は携帯通信端末１の動作を、図７及び図８は基地局２−１の動作をそれぞれ、示している。これらの図において、携帯通信端末１は、自局の位置検出をＧＰＳ受信部１０５により行う（ステップ３００）。
【００３４】
ＧＰＳ受信部１０５は、複数のＧＰＳ衛星からアンテナ１００を介して受信した衛星の位置情報に基づいて自局の位置を算出する。なお、携帯通信端末１における位置検出は、本実施の形態のように携帯通信端末１が単独で行なってもよいし、基地局のサポートを得て移動端末が位置検出を行うような方法（例えばＧＰＳ衛星の位置情報を基地局２−１から携帯通信端末１に送り、携帯通信端末１ではその情報を基にＧＰＳ衛星からの電波を検出、受信して位置検出を行う等の方法）でもよい。
【００３５】
携帯通信端末１は検出した自局の位置を所定の頻度で基地局２−１へ報告し（ステップ３０１）、基地局２−１では携帯通信端末１の位置情報を受信し、基地局２−１内の位置情報記憶部２０５１に格納する（ステップ３０２、３０３）。（基地局２−１は、必要に応じて携帯通信端末１から位置情報の報告を受けた時間情報も格納する。）
携帯通信端末１は、ユーザによる操作部１１１における所定の操作により基地局２−１に対し、下り方向データ通信速度の変動予測情報の通知を要求する（ステップ４００）。
基地局２−１では、携帯通信端末１が要求した下り方向データ通信速度の変動予測情報の算出を行い、携帯通信端末１に通知する。この処理については基地局の動作として、後述する。
【００３６】
次いで、携帯通信端末１は、基地局２−１より下り方向データ通信速度の変動予測情報を受信すると（ステップ４０１）、表示部１１０に受信した下り方向データ通信速度の変動予測情報を数値、もしくはグラフ等の形式で表示する（ステップ４０２）。携帯通信端末１のユーザは、表示部１１０に表示された情報を確認し、この情報を基にデータ通信（下り方向のデータダウンロード）を行うか否かを判断する（ステップ４０３）。高い下り方向データ通信速度が得られる場合には、データ通信（例えば、データのダウンロード）を行い（ステップ４０４、４０５）、他方、高い下り方向データ通信速度が得られない場合には、データ通信を行なわず、携帯通信端末１の動作を終了する（ステップ４０３）。
【００３７】
また、基地局２−１では、携帯通信端末１より下り方向データ通信速度の変動予測情報の通知要求を受信すると（ステップ５００）、基地局２−１内の移動情報検出部２０５２において、位置情報記億部２０５１に格納した移動端末の位置情報の変化に基づいて携帯通信端末１の移動情報（移動方向、速度）を算出する（ステップ５０１）。
【００３８】
次に、基地局２−１内のＤＲＣ変動予測部２０５４において、携帯通信端末１の位置、移動方向及び速度とＤＲＣマップ記憶部２０５３に格納されたＤＲＣマップからＤＲＣの変動予測情報が算出される（ステップ５０２）。次いで、下り方向データ通信速度の変動予測情報の通知を要求した移動端末以外に、基地局と接続してデータ通信中の携帯通信端末が存在するか否かが判定される（ステップ５０３）。
【００３９】
データ通信中の携帯通信端末が存在する場合には、現在、データ通信中の携帯通信端末についても同様にＤＲＣの変動予測情報が算出される（ステップ５０４）。次いで、下り方向データ通信速度の変動予測情報の通知を要求した携帯通信端末１のＤＲＣ変動予測情報及び現在、基地局２−１と接続しデータ通信中の携帯通信端末のＤＲＣ変動予測情報が基地局２−１の制御部２０３内のスケジューラ２０３０に入力され、スケジューラ２０３０は入力された各携帯通信端末のＤＲＣ変動予測情報を基に時分割単位毎に、どの携帯通信端末と通信するかを判定する（ステップ５０５）。ここで、各時分割単位での通信で使用される下り方向の伝送速度（変調速度）の予測値は、基本的にその時分割単位におけるＤＲＣの値に基づいて可能な限り高い伝送速度（変調速度）が使用されるものとする。
【００４０】
携帯通信端末に通知される下り方向データ通信速度の変動予測情報の算出対象となる時間範囲は、下り方向のデータ通信の内容が携帯通信端末１によるデータダウンロードであることを考慮すると、現時点（基地局２−１へ下り方向データ通信速度の変動予測情報の通知を要求した時点、もしくは携帯通信端末１から最新の位置情報を基地局２−１ヘ通知した時点）から数分または十数分程度が妥当と考えられるが、この時間範囲は携帯通信端末でのユーザによる所定の操作により段階的に選択されるようにしてもよい。この時間範囲での携帯通信端末１の移動範囲が隣接基地局のサービスエリアまで跨るか（ハンドオフを含むか）否かが判定される（ステップ５０６）。
【００４１】
ステップ５０６の判定が否定された場合には、スケジューラ２０３０での判定の結果、各移動端末毎に下り方向データ通信速度の変動予測情報が求められ、基地局に対し下り方向データレート変動予測情報の通知を要求した移動端末へ該当する予測情報の通知が行われる（ステップ５１０）。ここで、ＤＲＣ変動予測部２０５４は下り方向データ通信速度の変動予測専用のスケジューラを備えるうように構成してもよい。制御部２０３のスケジューラ２０３０は既述したように、現在データ通信中の携帯通信端末に対して時分割単位毎にどの端末と通信を行うかのスケジューリングを行っており、ＤＲＣ変動予測部２０５４が専用のスケジューラを持てば制御部２０３のスケジューラ２０３０にかかる負担を軽減できると考えられる。
【００４２】
一方、ステップ５０６の判定が肯定された場合、すなわち、上記時間範囲での携帯通信端末の移動範囲が隣接基地局のサービスエリアまで跨る場合（ハンドオフが含まれる場合）には、現在、携帯通信端末１がそのサービスエリア内に位置する基地局２−１は移動情報検出部２０５２において算出した携帯通信端末１の移動情報と位置を制御局（もしくはそれに類する基地局制御装置）３を介して該当する隣接基地局（ハンドオフ先になると予想される基地局）へ通知するとともにそのサービスエリア内での対象移動端末の下り方向データレート変動予測情報算出を同様に制御局を介して要求する（ステップ５０７）。
【００４３】
要求を受けた隣接基地局は既述したのと同様の方法で自局サービスエリア内における対象となる携帯通信端末について下り方向データ通信速度の変動予測情報を算出し、要求元の基地局へ制御局３を介して通知する（ステップ５０８）。通知を受けた基地局（現在移動端末がそのサービスエリア内に位置する基地局）２−１では隣接基地局におけるサービスエリア内での下り方向データ通信速度の変動予測情報と自局サービスエリア内での前記情報を結合した複数の基地局サービスエリアに跨る下り方向データ通信速度の変動予測情報を作成し、情報要求元の携帯通信端末へ通知する（ステップ５０９）。
【００４４】
なお、上記説明において携帯通信端末１が検出した位置情報は携帯通信端末１内の記憶装置に格納し、基地局に下り方向データ通信速度の変動予測情報の通知を要求する際に、位置情報の変化から移動情報（移動方向、速度）を携帯通信端末１で算出し、位置情報及び移動情報を下り方向データ通信速度の変動予測情報通知要求と共に基地局へ送るようにしてもよい。
【００４５】
この場合、携帯通信端末１が基地局と接続しデータ通信を開始してからは所定の頻度で携帯通信端末から基地局へ位置情報、移動情報を通知するようにし、基地局では最新の情報のみを基地局内の記憶装置に格納しておき、基地局サービスエリア内の携帯通信端末から下り方向データレート変動予測情報の要求があった時には基地局エリア内におけるデータ通信中の携帯通信端末の状態も考慮に入れて、情報要求をした携帯通信端末の下り方向データ通信速度の変動予測情報を算出できるようにする。これは、移動端末から基地局へ位置情報、移動情報を通知するのが、基地局に下り方向データレート変動予測情報の通知を要求する時だけにすると、データ通信中の端末についてもＤＲＣ変動予測情報を求めた上でスケジューラにおいて予測情報通知要求を出した携帯通信端末の下り方向データ通信速度の変動予測情報を算出することができなくなるので、この事態を回避するためである。
【００４６】
また、上記説明中、基地局２−１内のＤＲＣ変動予測部２０５４とＤＲＣマップ記憶部２０５３は、制御局（もしくはそれに類する基地局制御装置）３内に設けるようにしてもよい。この場合、制御局３内のＤＲＣマップ記憶部はその制御局３が制御する基地局すべてのＤＲＣマップを格納するようにし、各基地局からは下り方向データ通信速度の変動予測情報の通知要求を行った携帯通信端末及びその基地局とデータ通信中の携帯通信端末の位置情報、移動情報が制御局３へ送られ、制御局３からは前記情報要求を行った移動端末についての下り方向データレート変動予測情報が該当基地局へ送られ、基地局は前記変動予測情報の通知要求を行った携帯通信端末へ下り方向データ通信速度の変動予測情報を通知するようにすればよい。
【００４７】
以上に説明したように、本実施の形態によれば、基地局から携帯通信端末への下り方向のデータ通信速度が、該携帯通信端末における基地局信号の受信状態により大きく変化するように制御される移動通信システムにおいて、前記携帯通信端末は、自局の位置検出機能を有し、自局の位置情報を所定の頻度で基地局に送出し、かつ下り方向データ通信速度の変動予測情報の通知要求を送出し、前記基地局は、前記通知要求を受信し、前記携帯通信端末から受信した位置情報、及び該位置情報から算出した移動情報に基づいて現時点から所定時間内の下り方向データ通信速度の変動予測情報を算出し、該変動予測情報を前記携帯通信端末に通知すると共に、前記携帯通信端末は、前記変動予測情報を受信し、該変動予測情報を表示手段に表示するようにしたので、下記に示すような効果が得られる。
【００４８】
すなわち、本実施の形態によれば、携帯通信端末のユーザは、データ通信を開始する前に、現時点からある時間内の下り方向データ通信速度の変動予測情報を確認することができる。この結果、携帯通信端末のユーザは、予想外の長時間ダウンロードを回避できる確率が高くなり、長い時間ダウンロードの終了を待つストレスから開放される可能性が高くなる。
また、高い下りデータレートが得られる受信状態を選択してデータ通信（データダウンロード）を行うことにより、基地局設備（能力）の効率的な利用が可能となる。
【００４９】
さらに、高い下りデータレートが得られる受信状態を選択してデータ通信（データダウンロード）を行うことにより、データダウンロード時間の短縮が可能となる。この結果、ユーザがキー入力等の操作を行ったときに、操作感が悪化する可能性（CPU処理能力の一部がデータ通信処理に割かれることに起因するもの）が低減される。
【００５０】
また、携帯電話などRF部分を有する携帯通信端末の消費電流はRF部分での消費電流が支配的であり、RF部分での消費電流はデータ通信速度よりもRF部が起動している時間に大きく左右されるが、データダウンロード時間の短縮により消費電流の削減が可能となる。
回線交換での時間課金を前提とした湯合には、データダウンロード時間の短縮により料金の低減が可能となる。
【００５１】
【発明の効果】
本発明によれば、基地局から携帯通信端末への下り方向のデータ通信速度が、該携帯通信端末における基地局信号の受信状態により大きく変化するように制御される移動通信システムにおいて、前記携帯通信端末は、自局の位置検出機能を有し、自局の位置情報を所定の頻度で基地局に送出し、かつ下り方向データ通信速度の変動予測情報の通知要求を送出し、前記基地局は、前記通知要求を受信し、前記携帯通信端末から受信した位置情報、及び該位置情報から算出した移動情報に基づいて現時点から所定時間内の下り方向データ通信速度の変動予測情報を算出し、該変動予測情報を前記携帯通信端末に通知すると共に、前記携帯通信端末は、前記変動予測情報を受信し、該変動予測情報を表示手段に表示するようにしたので、下記に示すような効果が得られる。
【００５２】
すなわち、本発明によれば、携帯通信端末のユーザは、データ通信を開始する前に、現時点からある時間内の下り方向データ通信速度の変動予測情報を確認することができる。この結果、携帯通信端末のユーザは、予想外の長時間ダウンロードを回避できる確率が高くなり、長い時間ダウンロードの終了を待つストレスから開放される可能性が高くなる。
また、高い下りデータレートが得られる受信状態を選択してデータ通信（データダウンロード）を行うことにより、基地局設備（能力）の効率的な利用が可能となる。
【００５３】
さらに、高い下りデータレートが得られる受信状態を選択してデータ通信（データダウンロード）を行うことにより、データダウンロード時間の短縮が可能となる。この結果、ユーザがキー入力等の操作を行ったときに、操作感が悪化する可能性（CPU処理能力の一部がデータ通信処理に割かれることに起因するもの）が低減される。
【００５４】
また、携帯電話などRF部分を有する携帯通信端末の消費電流はRF部分での消費電流が支配的であり、RF部分での消費電流はデータ通信速度よりもRF部が起動している時間に大きく左右されるが、データダウンロード時間の短縮により消費電流の削減が可能となる。
回線交換での時間課金を前提とした湯合には、データダウンロード時間の短縮により料金の低減が可能となる。
【図面の簡単な説明】
【図１】本発明の実施の形態に係る移動通信システムの構成を示すブロック図。
【図２】図１における携帯通信端末の具体的構成を示すブロック図。
【図３】図１における基地局の具体的構成を示すブロック図。
【図４】ＣＩＲ−ＤＲＣテーブルの内容を示す説明図。
【図５】図１における携帯通信端末及び基地局の動作の一例を示すフローチャート。
【図６】図１における携帯通信端末の動作の一例を示すフローチャート。
【図７】図１における基地局の動作の一例を示すフローチャート。
【図８】図１における基地局の動作の一例を示すフローチャート。
【符号の説明】
１携帯通信端末
２−１、２−２、２−３．… 基地局
３制御局
４ルータ
５ネットワーク
１００、２００アンテナ
１０１共用器
１０２復調器
１０３復号器
１０４ＣＰＵ
１０５ＧＰＳ受信部
１０７符号化器
１０８変調器
１０９メモリ
１１０表示部
１１１操作部
２０１受信部
２０２送信部
２０３制御部
２０４ネットワークインタフェース（Ｉ／Ｆ）部
２０５変動予測演算部
２０５１位置情報記憶部
２０５２移動情報検出部
２０５３ＤＲＣマップ記憶部
２０５４ＤＲＣ変動予測部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a Cdma2000 1x-EV DO system (or HDR system) or other base station signal (such as a pilot channel signal) in which the communication speed (data rate) in the direction from the base station to the mobile terminal (downlink direction) The present invention relates to a notification function of downlink data rate fluctuation prediction information to a mobile terminal user in a mobile communication system controlled so as to largely change depending on the reception state (received electric field strength, carrier-to-interference ratio = CIR).
[0002]
[Prior art]
In recent years, the cdma2000 1x-EV DO system has been developed as a next-generation high-speed wireless communication system.
The above cdma2000 1x-EV DO system is a standardized version of the HDR (High Data Rate) system, which is an extension of cdma2000 1x by Qualcomm. Std.T-64 1S-2000 CS0024 “cdma2000 High Rate Standardized by the “Packet Data Air Interface Specification”, cdmaOne method currently being serviced by KDDI in Japan (ARIB T-53 in Japan, EIA / TIA / IS-95 etc. in North America, Korea, etc.) However, the cdma2000 1x system corresponding to the third generation system (3G) is a system aimed at further improving the communication speed by specializing in data communication.
In cdma2000 lx-EV DO, EV means Evolution and DO means Data only.
[0003]
In the cdma2000 1x-EV DO method, when the reception state of the terminal is good by switching the modulation method of data transmitted from the base station to the terminal based on the information notified of the reception state received from the mobile communication terminal. Can use a high communication rate with low error tolerance but high speed, and a low speed but high error tolerance when reception is bad.
[0004]
Also, in the cdma2000 1x-EV DO downlink direction (from base station to mobile communication terminal), the time is divided in 1/600 second units, and only one mobile communication terminal communicates within that time. In addition, time division multiplex access (TDMA) is employed in which communication is performed with a plurality of portable communication terminals by switching the communication partner portable communication terminal according to time. As a result, it is always possible to transmit data with the maximum power to each mobile communication terminal, and data communication between mobile communication terminals can be performed at the fastest communication speed.
[0005]
[Problems to be solved by the invention]
On the other hand, in the cdma2000 1x-EV DO system described above, the data communication speed in the direction from the base station to the mobile communication terminal varies greatly depending on the reception state (for example, reception field strength, carrier-to-interference ratio = CIR) in the mobile communication terminal. It has the characteristic.
For example, in a mobile communication terminal, if the reception state is the best, data communication at a communication speed of 2.4 Mbps is possible, but if the reception state is bad, the data communication speed is reduced to about several tens of kbps. End up. Then, if downloading of a relatively large amount of data is started in a situation where the reception state at the mobile communication terminal is poor and only a low downlink data communication speed can be obtained, the following problems occur.
[0006]
First, since it takes a long time to complete the data download, the user is restricted in the time and cannot provide an environment where sufficient service can be performed.
Secondly, the communication time becomes long because the communication time becomes long.
Thirdly, during the download period, a part of CPU (central processing unit) processing capacity is devoted to data communication processing, and the response to user operations such as key input becomes slow.
[0007]
Fourth, the current consumption of the mobile communication terminal having the RF unit is dominated by the current consumption in the RF unit, and the current consumption in the RF unit greatly depends on the time when the RF unit is activated rather than the data communication speed. Therefore, performing data communication for a long time at a low data communication speed consumes more current than when performing data communication for a short time at a high data communication speed.
Fifth, when receiving a service that downloads video data or music data from the communication network side to the mobile communication terminal and also plays back on the terminal in parallel (video or music streaming playback), a predetermined value is used. The above downlink data communication speed is required. However, if the required downlink data communication speed cannot be obtained at this time, there may be effects such as image quality, sound quality degradation, video stoppage, and sound interruption. , Not enough service quality.
[0008]
The present invention has been made in view of such circumstances. By promptly and accurately notifying a user of a reception state that changes significantly depending on a location, the user can perform data communication in a good reception state. An object of the present invention is to provide a mobile communication terminal and a base station of a mobile communication system that can perform the above.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the invention according to claim 1 is such that the data communication speed in the downlink direction from the base station to the mobile communication terminal varies greatly depending on the reception state of the base station signal in the mobile communication terminal. In the mobile communication system to be controlled, the mobile communication terminal has a position detection function of the own station, sends the position information of the own station to the base station at a predetermined frequency, and information on fluctuation prediction of the downlink data communication speed The base station receives the notification request, and the downlink data within a predetermined time from the present time based on the position information received from the mobile communication terminal and the movement information calculated from the position information. The communication speed fluctuation prediction information is calculated, the fluctuation prediction information is notified to the mobile communication terminal, and the mobile communication terminal receives the fluctuation prediction information and displays the fluctuation prediction information on a display unit. And wherein the Shimesuru.
[0010]
In the mobile communication system according to the second aspect of the present invention, the data communication speed in the downlink direction from the base station to the mobile communication terminal is controlled so as to vary greatly depending on the reception state of the base station signal in the mobile communication terminal. In the portable communication terminal, the portable communication terminal has a position detecting function of the own station, sends the position information of the own station to the base station at a predetermined frequency, and notifies the fluctuation prediction information of the downlink data communication speed. It transmits the request, receives downlink data communication speed fluctuation prediction information calculated by the base station, and displays the fluctuation prediction information on a display means.
[0011]
According to a third aspect of the present invention, there is provided a mobile communication system in which a downlink data communication speed from a base station to a mobile communication terminal is controlled so as to vary greatly depending on a reception state of a base station signal in the mobile communication terminal. In the base station, the base station receives a notification request for downlink data communication speed fluctuation prediction information from the mobile communication terminal, and receives the position information received from the mobile communication terminal and the movement information calculated from the position information. Based on the above, the fluctuation prediction information of the downlink data communication speed within a predetermined time from the present time is calculated, and the fluctuation prediction information is notified to the mobile communication terminal.
[0012]
According to a fourth aspect of the present invention, there is provided a mobile communication system in which a downlink data communication speed from a base station to a mobile communication terminal is controlled so as to vary greatly depending on a reception state of a base station signal in the mobile communication terminal. In the portable communication terminal, the portable communication terminal has a position detection function of the own station, sends the position information and movement information of the own station to the base station at a predetermined frequency, and predicts fluctuations in the downlink data communication speed. An information notification request is transmitted, and fluctuation prediction information of the downlink data communication speed calculated by the base station is received, and the fluctuation prediction information is displayed on a display means.
[0013]
According to the fifth aspect of the present invention, there is provided a mobile communication system in which a downlink data communication speed from a base station to a mobile communication terminal is controlled so as to vary greatly depending on a reception state of a base station signal in the mobile communication terminal. In the base station, the base station receives a notification request for downlink data communication speed fluctuation prediction information from the mobile communication terminal, and based on the position information and the movement information received from the mobile communication terminal for a predetermined time from the present time. The fluctuation prediction information of the downlink data communication speed is calculated, and the fluctuation prediction information is notified to the mobile communication terminal.
[0014]
According to a sixth aspect of the present invention, there is provided a mobile communication system in which a downlink data communication speed from a base station to a mobile communication terminal is controlled so as to vary greatly depending on a reception state of a base station signal in the mobile communication terminal. In the portable communication terminal, an operation means for performing various settings and instructions, a position detection means for detecting the position of the own station, a display means for displaying various data, and a detection output of the position detection means Station position information is transmitted to the base station at a predetermined frequency, and a downlink data communication speed fluctuation prediction information notification request is transmitted based on the operation of the operation means, and the downlink direction calculated by the base station And control means for receiving fluctuation prediction information of data communication speed and displaying the fluctuation prediction information on the display means.
[0015]
According to the seventh aspect of the present invention, there is provided a mobile communication system in which a downlink data communication speed from a base station to a mobile communication terminal is controlled so as to vary greatly depending on a reception state of a base station signal in the mobile communication terminal. Storage means for storing position information of the mobile communication terminal received from the mobile communication terminal at a predetermined frequency, and movement information of the mobile communication terminal based on the position information stored in the storage means The mobile information detection means for calculating the mobile communication terminal and the mobile communication terminal receives a notification request for prediction of fluctuations in downlink data communication speed, and the position information stored in the storage means and the movement information detection from the position information Based on the movement information calculated by the means, the fluctuation prediction information of the downlink data communication speed within a predetermined time from the current time is calculated, and the fluctuation prediction information is And having a control means for notifying.
[0016]
In the mobile communication system according to the eighth aspect of the present invention, the data communication speed in the downlink direction from the base station to the mobile communication terminal is controlled so as to largely change depending on the reception state of the base station signal in the mobile communication terminal. Operating means for performing various settings and instructions, position detecting means for detecting the position of the own station, storage means for storing position information detected by the position detecting means, and various data Based on the display means for displaying and the position information stored in the storage means, the movement information of the own station is calculated, the position information and movement information of the own station are sent to the base station at a predetermined frequency, and the operation means A downlink data communication speed fluctuation prediction information notification request is transmitted based on the operation, and the downlink data communication speed fluctuation prediction information calculated by the base station is received, and the fluctuation prediction is received. And having a control means for displaying the broadcast on the display means.
[0017]
The invention according to claim 9 is a mobile communication system in which the data communication speed in the downlink direction from the base station to the mobile communication terminal is controlled so as to vary greatly depending on the reception state of the base station signal in the mobile communication terminal. Storage means for storing the location information and movement information of the mobile communication terminal received from the mobile communication terminal at a predetermined frequency, and a notification request for the downlink data communication speed fluctuation prediction information from the mobile communication terminal. Based on the position information and movement information stored in the storage means, calculate fluctuation prediction information of the downlink data communication speed within a predetermined time from the present time, and notify the mobile communication terminal of the fluctuation prediction information And a control means.
[0018]
ADVANTAGE OF THE INVENTION According to this invention, the user of a portable communication terminal can confirm the fluctuation | variation prediction information of the downlink data communication speed within a certain time from the present time, before starting data communication. As a result, the user of the mobile communication terminal has a higher probability of being able to avoid an unexpectedly long time download, and is more likely to be freed from the stress of waiting for the end of the long time download.
In addition, by selecting a reception state in which a high downlink data rate can be obtained and performing data communication (data download), it is possible to efficiently use base station equipment (capability).
[0019]
Furthermore, the data download time can be shortened by selecting a reception state in which a high downlink data rate is obtained and performing data communication (data download). As a result, when the user performs an operation such as key input, the possibility that the operational feeling deteriorates (because part of the CPU processing capacity is devoted to data communication processing) is reduced.
[0020]
In addition, the current consumption of mobile communication terminals that have an RF part such as mobile phones is dominated by the current consumption in the RF part, and the current consumption in the RF part is larger during the time the RF part is activated than the data communication speed. Although it depends, it is possible to reduce current consumption by shortening the data download time.
For hot springs that are premised on time charges for circuit switching, it is possible to reduce charges by shortening the data download time.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows the configuration of a mobile communication system according to an embodiment of the present invention. In the figure, the mobile communication system according to the present embodiment includes a mobile communication terminal 1, base stations 2-1, 2-2, 2-3, ..., base stations 2-1, 2-2, 2- And a control station 3 that controls the overall control of. The control station 3 is connected to a network 5 such as the Internet via a router 4. In this mobile communication system, the data communication speed in the downlink direction from the base station to the mobile communication terminal is controlled so as to change greatly depending on the reception state of the base station signal in the mobile communication terminal.
[0022]
In the above configuration, the mobile communication terminal 1 has a position detection function of the own station, and the base station that has jurisdiction over the service area in which the own station is located at a predetermined frequency, for example, the base station 2-1, And a request for notification of fluctuation prediction information of the downlink data communication speed is transmitted. (Hereinafter, the base station will be described by taking the base station 2-1 as an example. Of course, the configuration and operation of other base stations are the same as those of the base station 2-1.)
On the other hand, the base station 2-1 receives the notification request and, based on the position information received from the mobile communication terminal 1 and the movement information calculated from the position information, the downlink data communication speed within a predetermined time from the present time. The fluctuation prediction information is calculated and the fluctuation prediction information is notified to the mobile communication terminal 1. The mobile communication terminal 1 receives the fluctuation prediction information and displays the fluctuation prediction information on a display unit.
[0023]
Next, the configuration of the mobile communication terminal 1 is shown in FIG. FIG. 2 shows a configuration of the mobile communication terminal 1 adopting the cdma2000 1x-EV DO system according to an embodiment of the present invention.
As shown in FIG. 2, the mobile communication terminal 1 according to this embodiment includes an RF unit including an antenna 100, a duplexer 101, a demodulator 102, and a modulator 108, and a baseband including a decoder 103 and an encoder 107. A processing unit, a GPS receiving unit 105 as a position detecting unit for detecting the position of the own station, a CPU 104, a memory 109, a display unit 110 including a liquid crystal display, and an operation unit 111 such as a keypad and a keyboard are provided.
[0024]
In addition, an external interface with a personal computer (PC) 113 (for example, serial port, parallel port, USB, blue-tooth, infrared communication, 10base-T LAN, etc.) 112 so that the mobile communication terminal 1 can be used as a wireless modem. It has.
[0025]
The demodulator 102 demodulates the multiplexed signal from the received signal in the baseband band by a demodulation method corresponding to the modulation method of the received signal received from the base station, for example, the base station 2-1. In the present embodiment, demodulation is performed by any one of three demodulation schemes of QPSK (quadriphase phase shift keying), 8PSK (8 phase shift keying), and 16QAM (16 quadrature amplitude modulation). The received data demodulated by the demodulator 102 is decoded by the decoder 103. That is, the decoder 103 despreads the received multiplexed signal that has been spread spectrum.
[0026]
Here, when there is received data assigned to the own station (for example, data desired to be downloaded), the received data is output from the decoder 103 to the CPU 104. This received data is processed in the CPU 104 or sent to an external PC 113 or the like via the CPU 104 and the external interface 112.
[0027]
The CPU 9 determines whether there is transmission data generated in the portable communication terminal or input from the external PC 29 via the external interface 27. If there is transmission data, the CPU 9 The transmission data is output to the encoder 17. The transmission data is further encoded by the encoder 17, modulated by a modulator 19 by a specific modulation scheme (for example, QPSK), and transmitted to the base station via the duplexer 3 and the antenna 1. It has become.
[0028]
Next, the base station 2-1 includes an antenna 200, a reception unit 201, a transmission unit 202, a control unit 203, a network interface (I / F) unit 204 that interfaces with the control station, and downlink data in the mobile communication terminal. And a fluctuation prediction calculation unit 205 that calculates communication speed fluctuation prediction information.
The reception unit 201 receives transmission data from the mobile communication terminal, and the transmission unit 202 has a function of transmitting transmission data to the mobile communication terminal.
[0029]
Further, the fluctuation prediction calculation unit 205 includes a position information storage unit 2051, a movement information detection unit 2052, a DRC map storage unit 2053, and a DRC fluctuation prediction unit 2054.
The position information storage unit 2051 is a storage device that stores position information (for example, longitude and latitude information) transmitted from the mobile communication terminal 1. The movement information detection unit 2052 has a function of detecting the movement direction and movement speed of the mobile communication terminal 1 from the position information of the mobile communication terminal 1 read from the position information storage unit 2051.
[0030]
The DRC map storage unit 2053 is a storage device having a DRC (Data Rate Control Bit) map. DRC means “the highest transmission rate that can be received at a predetermined error rate or less” that is expected from the downlink reception state measured by the mobile terminal notified from the mobile terminal to the base station. However, in this embodiment, it is used as the downlink direction predicted data communication speed value for each place in the local station service area.
[0031]
Here, the DRC map is typically obtained by measuring in advance the reception radio wave status (location of CIR (carrier-to-interference ratio) of a downlink pilot signal output from the base station to the mobile communication terminal 1) for each place in the local station service area. A typical CIR value map is converted into a DRC value map using the CIR-DRC conversion table shown in Fig. 4. Incidentally, the CIR is calculated by the following equation.
CIR = (Ec / lo) / (1-Ec / lo) (1)
Ec / Io represents pilot signal strength versus total received signal strength.
[0032]
The DRC fluctuation prediction unit 2054 calculates DRC fluctuation prediction information that is fluctuation prediction information of the downlink data communication speed of the mobile communication terminal 1.
The control unit 203 includes a scheduler 2030 and controls each unit. The scheduler 2030 performs scheduling for which mobile communication terminal is to communicate with each mobile communication terminal currently in data communication for each time division unit.
[0033]
The operation of the mobile communication system according to the present embodiment configured as described above will be described with reference to the flowcharts of FIGS. 5 shows the operation of the mobile communication terminal 1 and the base station 2-1, FIG. 6 shows the operation of the mobile communication terminal 1, and FIGS. 7 and 8 show the operation of the base station 2-1. In these drawings, the mobile communication terminal 1 detects the position of its own station by the GPS receiver 105 (step 300).
[0034]
The GPS receiving unit 105 calculates the position of the own station based on the position information of the satellites received from the plurality of GPS satellites via the antenna 100. Note that the position detection in the mobile communication terminal 1 may be performed by the mobile communication terminal 1 alone as in the present embodiment, or a method in which the mobile terminal performs position detection with the support of the base station (for example, The GPS satellite position information may be sent from the base station 2-1 to the mobile communication terminal 1, and the mobile communication terminal 1 may detect and receive a radio wave from the GPS satellite based on the information to detect the position). .
[0035]
The mobile communication terminal 1 reports the detected position of the own station to the base station 2-1 with a predetermined frequency (step 301), and the base station 2-1 receives the position information of the mobile communication terminal 1, and the base station 2- 1 (steps 302 and 303). (The base station 2-1 also stores time information received from the portable communication terminal 1 as needed).
The mobile communication terminal 1 requests the base station 2-1 to notify the downlink data communication speed fluctuation prediction information by a predetermined operation on the operation unit 111 by the user (step 400).
The base station 2-1 calculates the downlink data communication speed fluctuation prediction information requested by the mobile communication terminal 1 and notifies the mobile communication terminal 1 of the calculation. This process will be described later as the operation of the base station.
[0036]
Next, when the mobile communication terminal 1 receives the downlink data communication speed fluctuation prediction information from the base station 2-1 (step 401), the mobile communication terminal 1 receives the downlink data communication speed fluctuation prediction information received on the display unit 110 as a numerical value, or It is displayed in the form of a graph or the like (step 402). The user of the mobile communication terminal 1 checks the information displayed on the display unit 110, and determines whether or not to perform data communication (downward data download) based on this information (step 403). When a high downlink data communication speed is obtained, data communication (for example, data download) is performed (steps 404 and 405). On the other hand, when a high downlink data communication speed cannot be obtained, data communication is performed. Without the operation, the operation of the mobile communication terminal 1 is terminated (step 403).
[0037]
Further, when the base station 2-1 receives the notification of the downlink data communication speed fluctuation prediction information from the mobile communication terminal 1 (step 500), the mobile information detection unit 2052 in the base station 2-1 receives the position information. Based on the change in the position information of the mobile terminal stored in the storage unit 2051, the movement information (movement direction, speed) of the mobile communication terminal 1 is calculated (step 501).
[0038]
Next, the DRC fluctuation prediction unit 2054 in the base station 2-1 calculates DRC fluctuation prediction information from the position, moving direction and speed of the mobile communication terminal 1 and the DRC map stored in the DRC map storage unit 2053. (Step 502). Next, it is determined whether there is a mobile communication terminal connected to the base station and performing data communication other than the mobile terminal that has requested the notification of the downlink data communication speed fluctuation prediction information (step 503).
[0039]
If there is a mobile communication terminal in data communication, DRC fluctuation prediction information is also calculated for the mobile communication terminal currently in data communication (step 504). Next, the DRC fluctuation prediction information of the mobile communication terminal 1 which has requested the notification of the downlink data communication speed fluctuation prediction information and the DRC fluctuation prediction information of the mobile communication terminal currently connected to the base station 2-1 and performing data communication are Input to the scheduler 2030 in the control unit 203 of the station 2-1, and the scheduler 2030 determines which mobile communication terminal to communicate for each time division unit based on the input DRC fluctuation prediction information of each mobile communication terminal. (Step 505). Here, the predicted value of the downlink transmission rate (modulation rate) used in communication in each time division unit is basically the highest possible transmission rate (modulation rate) based on the DRC value in that time division unit. ) Shall be used.
[0040]
Considering that the content of the downlink data communication is data download by the mobile communication terminal 1, the time range to be calculated for the downlink data communication speed fluctuation prediction information notified to the mobile communication terminal is the current (base About several minutes or more than ten minutes from the time when the station 2-1 is requested to notify the downlink data communication speed fluctuation prediction information or the latest position information is notified from the mobile communication terminal 1 to the base station 2-1. However, this time range may be selected stepwise by a predetermined operation by the user at the mobile communication terminal. It is determined whether or not the movement range of the mobile communication terminal 1 in this time range extends to the service area of the adjacent base station (including handoff) (step 506).
[0041]
If the determination in step 506 is negative, as a result of the determination in the scheduler 2030, the downlink data communication speed fluctuation prediction information is obtained for each mobile terminal, and the downlink data rate fluctuation prediction information is transmitted to the base station. The corresponding prediction information is notified to the mobile terminal that has requested the notification (step 510). Here, the DRC fluctuation prediction unit 2054 may be configured to include a scheduler dedicated to fluctuation prediction of the downlink data communication speed. As described above, the scheduler 2030 of the control unit 203 schedules which terminal performs communication for each time division unit with respect to the mobile communication terminal currently performing data communication, and the DRC fluctuation prediction unit 2054 is dedicated. It is considered that the burden on the scheduler 2030 of the control unit 203 can be reduced if the scheduler is provided.
[0042]
On the other hand, if the determination in step 506 is affirmative, that is, if the movement range of the mobile communication terminal in the above time range extends to the service area of the adjacent base station (when handoff is included), the mobile communication terminal is currently The base station 2-1 where 1 is located in the service area corresponds to the movement information and position of the mobile communication terminal 1 calculated by the movement information detection unit 2052 via the control station (or similar base station control device) 3. Notifying an adjacent base station (a base station expected to be a handoff destination) and requesting calculation of downlink data rate fluctuation prediction information of the target mobile terminal in the service area through the control station in the same manner (step 507) .
[0043]
The neighboring base station that has received the request calculates the downlink data communication speed fluctuation prediction information for the target mobile communication terminal in the local station service area in the same manner as described above, and controls it to the requesting base station. Notification is made via the station 3 (step 508). In the base station (the base station in which the mobile terminal is currently located in the service area) 2-1 that has received the notification, the fluctuation prediction information of the downlink data communication speed in the service area in the adjacent base station and the local service area Fluctuation information for downlink data communication speeds across a plurality of base station service areas combined with the above information is created and notified to the information requesting mobile communication terminal (step 509).
[0044]
Note that the location information detected by the mobile communication terminal 1 in the above description is stored in a storage device in the mobile communication terminal 1, and when requesting notification of fluctuation prediction information of the downlink data communication speed to the base station, the location information Movement information (movement direction, speed) may be calculated by the mobile communication terminal 1 from the change, and the position information and movement information may be sent to the base station together with the downlink data communication speed fluctuation prediction information notification request.
[0045]
In this case, after the mobile communication terminal 1 connects to the base station and starts data communication, the mobile communication terminal notifies the base station of the location information and movement information at a predetermined frequency. Is stored in the storage device in the base station, and when the mobile communication terminal in the base station service area requests downlink data rate fluctuation prediction information, the state of the mobile communication terminal that is performing data communication in the base station area is also Taking into consideration, it is possible to calculate the downlink data communication speed fluctuation prediction information of the mobile communication terminal that has requested the information. This is because if the mobile terminal notifies the base station of the location information and the mobile information only when the base station requests the notification of the downlink data rate fluctuation prediction information, the DRC fluctuation prediction is also made for the terminal in data communication. This is to avoid this situation because it is impossible to calculate the downlink data communication speed fluctuation prediction information of the mobile communication terminal that has issued the prediction information notification request in the scheduler after obtaining the information.
[0046]
In the above description, the DRC fluctuation prediction unit 2054 and the DRC map storage unit 2053 in the base station 2-1 may be provided in the control station (or similar base station control device) 3. In this case, the DRC map storage unit in the control station 3 stores the DRC maps of all the base stations controlled by the control station 3, and each base station sends a request for notification of fluctuation prediction information of the downlink data communication speed. The location information and the movement information of the mobile communication terminal that has performed and the mobile communication terminal in data communication with the base station are sent to the control station 3, and the downlink data rate for the mobile terminal that has made the information request from the control station 3 The fluctuation prediction information may be sent to the corresponding base station, and the base station may notify the mobile communication terminal that has made the fluctuation prediction information notification request of the downlink data communication speed fluctuation prediction information.
[0047]
As described above, according to the present embodiment, the data communication speed in the downlink direction from the base station to the mobile communication terminal is controlled so as to largely change depending on the reception state of the base station signal in the mobile communication terminal. In the mobile communication system, the mobile communication terminal has a position detecting function of the own station, sends the position information of the own station to the base station at a predetermined frequency, and notifies the downlink data communication speed fluctuation prediction information. The base station receives the notification request, and the downlink data communication speed within a predetermined time from the present time based on the position information received from the mobile communication terminal and the movement information calculated from the position information. The fluctuation prediction information is calculated, the fluctuation prediction information is notified to the portable communication terminal, and the portable communication terminal receives the fluctuation prediction information and displays the fluctuation prediction information on a display means. Since the way, advantages are obtained as shown below.
[0048]
That is, according to the present embodiment, the user of the mobile communication terminal can confirm the downlink data communication speed fluctuation prediction information within a certain time from the current time before starting the data communication. As a result, the user of the mobile communication terminal has a higher probability of being able to avoid an unexpectedly long time download, and is more likely to be freed from the stress of waiting for the end of the long time download.
In addition, by selecting a reception state in which a high downlink data rate can be obtained and performing data communication (data download), it is possible to efficiently use base station equipment (capability).
[0049]
Furthermore, the data download time can be shortened by selecting a reception state in which a high downlink data rate is obtained and performing data communication (data download). As a result, when the user performs an operation such as key input, the possibility that the operational feeling deteriorates (because part of the CPU processing capacity is devoted to data communication processing) is reduced.
[0050]
In addition, the current consumption of mobile communication terminals that have an RF part such as mobile phones is dominated by the current consumption in the RF part, and the current consumption in the RF part is larger during the time the RF part is activated than the data communication speed Although it depends, it is possible to reduce current consumption by shortening the data download time.
For hot springs that are premised on time charges for circuit switching, it is possible to reduce charges by shortening the data download time.
[0051]
【The invention's effect】
According to the present invention, in the mobile communication system in which the data communication speed in the downlink direction from the base station to the mobile communication terminal is controlled so as to largely change depending on the reception state of the base station signal in the mobile communication terminal, the mobile communication The terminal has a position detection function of the own station, sends the position information of the own station to the base station at a predetermined frequency, and sends a notification request for downlink data communication speed fluctuation prediction information, the base station Receiving the notification request, calculating the fluctuation prediction information of the downlink data communication speed within a predetermined time from the current time based on the position information received from the mobile communication terminal and the movement information calculated from the position information, While notifying the mobile communication terminal of the fluctuation prediction information, the mobile communication terminal receives the fluctuation prediction information and displays the fluctuation prediction information on the display means. UNA effect can be obtained.
[0052]
That is, according to the present invention, the user of the mobile communication terminal can confirm the downlink data communication speed fluctuation prediction information within a certain time from the current time before starting the data communication. As a result, the user of the mobile communication terminal has a higher probability of being able to avoid an unexpectedly long time download, and is more likely to be freed from the stress of waiting for the end of the long time download.
In addition, by selecting a reception state in which a high downlink data rate can be obtained and performing data communication (data download), it is possible to efficiently use base station equipment (capability).
[0053]
Furthermore, the data download time can be shortened by selecting a reception state in which a high downlink data rate is obtained and performing data communication (data download). As a result, when the user performs an operation such as key input, the possibility that the operational feeling deteriorates (because part of the CPU processing capacity is devoted to data communication processing) is reduced.
[0054]
In addition, the current consumption of mobile communication terminals that have an RF part such as mobile phones is dominated by the current consumption in the RF part, and the current consumption in the RF part is larger during the time the RF part is activated than the data communication speed Although it depends, it is possible to reduce current consumption by shortening the data download time.
For hot springs that are premised on time charges for circuit switching, it is possible to reduce charges by shortening the data download time.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a mobile communication system according to an embodiment of the present invention.
FIG. 2 is a block diagram showing a specific configuration of the mobile communication terminal in FIG.
FIG. 3 is a block diagram showing a specific configuration of the base station in FIG. 1;
FIG. 4 is an explanatory diagram showing the contents of a CIR-DRC table.
FIG. 5 is a flowchart showing an example of operations of the mobile communication terminal and the base station in FIG.
6 is a flowchart showing an example of the operation of the mobile communication terminal in FIG.
7 is a flowchart showing an example of the operation of the base station in FIG.
8 is a flowchart showing an example of the operation of the base station in FIG.
[Explanation of symbols]
1 Mobile communication terminal
2-1, 2-2, 2-3. … base station
3 control stations
4 routers
5 network
100, 200 antenna
101 Duplexer
102 Demodulator
103 Decoder
104 CPU
105 GPS receiver
107 Encoder
108 modulator
109 memory
110 Display section
111 Operation unit
201 Receiver
202 Transmitter
203 control unit
204 Network interface (I / F) section
205 Fluctuation prediction calculator
2051 Location information storage unit
2052 Movement information detection unit
2053 DRC map storage unit
2054 DRC fluctuation prediction unit

Claims

In a mobile communication system in which the data communication speed in the downlink direction from the base station to the mobile communication terminal is controlled so as to largely change depending on the reception state of the base station signal in the mobile communication terminal,
The mobile communication terminal has a position detection function of the own station, sends the position information of the own station to the base station at a predetermined frequency, and sends a notification request for downlink data communication speed fluctuation prediction information,
The base station receives the notification request, and calculates the downlink data communication speed fluctuation prediction information within a predetermined time from the current time based on the position information received from the mobile communication terminal and the movement information calculated from the position information. Calculating and notifying the mobile communication terminal of the fluctuation prediction information,
The mobile communication terminal receives the fluctuation prediction information and displays the fluctuation prediction information on a display means.

In the mobile communication terminal of the mobile communication system in which the data communication speed in the downlink direction from the base station to the mobile communication terminal is controlled so as to largely change depending on the reception state of the base station signal in the mobile communication terminal,
The mobile communication terminal has a position detection function of the own station, sends the position information of the own station to the base station at a predetermined frequency, and sends a notification request for downlink data communication speed fluctuation prediction information, A mobile communication terminal of a mobile communication system, which receives fluctuation prediction information of a downlink data communication speed calculated by the base station and displays the fluctuation prediction information on a display means.

In a base station of a mobile communication system in which the data communication speed in the downlink direction from the base station to the mobile communication terminal is controlled so as to change greatly depending on the reception state of the base station signal in the mobile communication terminal,
The base station receives a notification request for downlink data communication speed fluctuation prediction information from the mobile communication terminal, and based on the position information received from the mobile communication terminal and the movement information calculated from the position information A base station of a mobile communication system, wherein fluctuation prediction information of downlink data communication speed within a predetermined time is calculated and the fluctuation prediction information is notified to the mobile communication terminal.

In the mobile communication terminal of the mobile communication system in which the data communication speed in the downlink direction from the base station to the mobile communication terminal is controlled so as to largely change depending on the reception state of the base station signal in the mobile communication terminal,
The mobile communication terminal has a position detection function of the own station, sends the position information and movement information of the own station to the base station at a predetermined frequency, and sends a notification request for downlink data communication speed fluctuation prediction information. In addition, the mobile communication terminal of the mobile communication system receives the fluctuation prediction information of the downlink data communication speed calculated by the base station and displays the fluctuation prediction information on a display means.

In a base station of a mobile communication system in which the data communication speed in the downlink direction from the base station to the mobile communication terminal is controlled so as to change greatly depending on the reception state of the base station signal in the mobile communication terminal,
The base station receives a notification request of downlink data communication speed fluctuation prediction information from the mobile communication terminal, and downloads downlink data within a predetermined time from the current time based on the position information and movement information received from the mobile communication terminal. A base station of a mobile communication system, which calculates communication speed fluctuation prediction information and notifies the mobile communication terminal of the fluctuation prediction information.

In the mobile communication terminal of the mobile communication system in which the data communication speed in the downlink direction from the base station to the mobile communication terminal is controlled so as to largely change depending on the reception state of the base station signal in the mobile communication terminal,
Operation means for making various settings and instructions;
Position detecting means for detecting the position of the own station;
Display means for displaying various data;
Captures the detection output of the position detecting means, sends the position information of the own station to the base station at a predetermined frequency, and sends a notification request for downlink data communication speed fluctuation prediction information based on the operation of the operating means. And control means for receiving fluctuation prediction information of the downlink data communication speed calculated by the base station and displaying the fluctuation prediction information on the display means,
A mobile communication terminal of a mobile communication system characterized by comprising:

In a base station of a mobile communication system in which the data communication speed in the downlink direction from the base station to the mobile communication terminal is controlled so as to change greatly depending on the reception state of the base station signal in the mobile communication terminal,
Storage means for storing position information of the mobile communication terminal received from the mobile communication terminal at a predetermined frequency;
Movement information detection means for calculating movement information of the mobile communication terminal based on position information stored in the storage means;
Based on the position information stored in the storage means and the movement information calculated by the movement information detection means based on the position information received from the mobile communication terminal in the downlink data communication speed fluctuation prediction information notification request. Control means for calculating fluctuation prediction information of the downlink data communication speed within a predetermined time from the present time, and notifying the fluctuation prediction information to the mobile communication terminal;
A base station of a mobile communication system characterized by comprising:

In the mobile communication terminal of the mobile communication system in which the data communication speed in the downlink direction from the base station to the mobile communication terminal is controlled so as to largely change depending on the reception state of the base station signal in the mobile communication terminal,
Operation means for making various settings and instructions;
Position detecting means for detecting the position of the own station;
Storage means for storing position information detected by the position detection means;
Display means for displaying various data;
Based on the location information stored in the storage means, the mobile station's movement information is calculated, the local station's location information and movement information is sent to the base station at a predetermined frequency, and the downlink direction based on the operation of the operation means A control means for sending a notification request for fluctuation prediction information on the data communication speed, receiving fluctuation prediction information on the downlink data communication speed calculated by the base station, and displaying the fluctuation prediction information on the display means;
A mobile communication terminal of a mobile communication system characterized by comprising:

In a base station of a mobile communication system in which the data communication speed in the downlink direction from the base station to the mobile communication terminal is controlled so as to change greatly depending on the reception state of the base station signal in the mobile communication terminal,
Storage means for storing position information and movement information of the mobile communication terminal received from the mobile communication terminal at a predetermined frequency;
A notification request for downlink data communication speed fluctuation prediction information is received from the mobile communication terminal, and the downlink data communication speed fluctuation within a predetermined time from the present time based on the position information and movement information stored in the storage means Control means for calculating prediction information and notifying the mobile communication terminal of the fluctuation prediction information;
A base station of a mobile communication system characterized by comprising: