JP3590259B2 - Communication systems, wireless base stations - Google Patents

Description

このようにＢＳ３においてサービスクラスｉ毎の送信許可確率を次のタイミングまでに再計算して更新した送信許可確率をＭＳ１，２に報知する。
【００５８】
すなわち、ＭＳ１，２とＢＳ３間の無線インターフェースの物理チャネル構成が、複数のサービスクラスにタイムスロットレベルまたは無線フレームレベルで時間的に分割された構成で、ＭＳ１，２とＢＳ３間でデータを送受信する場合、その通信品質に応じて所望のサービスクラスにマッピングされるので、ＢＳ３から報知されている各サービスクラス毎の送信許可確率情報に基づきＭＳ１，２が動作すれば、この時点におけるデータの送受信量（コード多重数）をＢＳ３側で管理することができる。
【００５９】
このようにこの第１実施形態のＣＤＭＡ通信システムによれば、ＭＳ１，２とＢＳ３間で送受信されるデータの通信品質に応じてコード多重数を分割して管理するので、最も要求品質の厳しいチャネルに多重数が制限されることがなくなる。これは要求品質の緩いサービスクラスのチャネルのコード多重数を、要求品質の厳しいサービスクラスのチャネルのコード多重数に比較して大きくするなど通信品質に応じて多重数を変えて管理するからであり、これにより１台のＢＳ３における端末収容数を増加することができる。特に、パケット通信などの、Ｂｅｓｔ Ｅｆｆｏｒｔ なＣＬ型通信のユーザパケットの多重数を大きくすれば、端末を効率よく収容することができる。
【００６０】
また、データの通信品質に応じてコード多重数を分割して管理することにより、パケット通信など、Ｂｅｓｔ Ｅｆｆｏｒｔ なＣＬ型通信のユーザパケットを転送するのに用いられる共有チャネルにアクセスが集中した場合にも、制御用の共有チャネルやＣＯ型通信などに主として用いられる個別チャネルの通信品質を所望の値以上に保つことができる。
この結果、チャネル利用効率の高いＣＤＭＡ通信システムを実現できる。
【００６１】
次に、図７を参照して本発明に係るＣＤＭＡ通信システムの第２実施形態について説明する。図７は本発明に係るＣＤＭＡ通信システムの第２の実施形態の構成を示す図である。
【００６２】
図７に示すように、このＣＤＭＡ通信システムは、無線端末１０〜１２（以下ＭＳ１０〜１２と称す）、無線基地局２０〜２Ｎ、３０〜３Ｎ（以下ＢＳ２０〜２Ｎ、ＢＳ３０〜３Ｎと称す）、無線基地局制御局４０、４１（以下ＢＳＣ４０、４１と称す）、移動交換局５０、５１（以下ＭＳＣ５０、５１と称す）、バックボーン網６０、固定端末７０、電話端末７１などから構成されている。
【００６３】
バックボーン網６０には、固定端末７０、ＭＳＣ５０、５１などが接続されている。ＭＳＣ５０には、ＢＳＣ４０が接続されている。ＢＳＣ４０にはＢＳ２０〜２Ｎが接続されている。またＭＳＣ５１には、ＢＳＣ４１が接続されている。ＢＳＣ４１にはＢＳ３０〜３Ｎが接続されている。各ＢＳ２０〜２Ｎ、３０〜３Ｎは自局のサービスエリア内に存在するＭＳ１０〜１２と無線回線を張り、上記固定端末７０とＭＳ１０〜１２との間でデータの送受信を行うものである。この際の無線回線のインターフェースには、上記に説明した図３に示すような論理チャネルが定義されている。ＭＳ１０〜１２はＢＳ２０〜２Ｎ、３０〜３Ｎの中のいずれかとそれぞれ無線回線を張ることによりデータの送受信を行う端末である。これらのＭＳ１０〜１２は少なくともＩＰパケットなどのＣＬ型通信を行うと共に、音声などのＣＯ型通信も可能な端末である。
【００６４】
例えばＢＳ２０は、図８に示すように、複数のアンテナ１００と、これらのアンテナ１００を利用してＲＦ信号を送受すると共に、ＲＦ送信信号とＲＦ受信信号とを分離多重し複数のアンテナ１００に接続する送受信増幅部（ＡＭＰ）１０１と、この送受信増幅部（ＡＭＰ）１０１の受信アンプから出力されたＲＦ受信信号を検波して、さらにＡ／Ｄ変換してベースバンド信号処理部（ＢＢ）１０３に伝送すると共に、ベースバンド信号処理部（ＢＢ）１０３によりベースバンド拡散された送信信号をＤ／Ａ変換し、直交変調によりＲＦ送信信号に変換する無線部（ＴＲ）１０２と、送信データの誤り訂正符号化、フレーム化、データ変調、拡散変調および受信信号の逆拡散、チップ同期、誤り復号、データの多重分離、セクタ間ハンドオーバ時の最大比合成などのベースバンド信号処理を行うベースバンド信号処理部１０３と、ＢＳＣ４０、ＭＳＣ５０との制御信号の送受信を行い、無線回線管理、無線回線の設定、解放などを行う基地局制御部（ＢＴＣ−ＣＮＴ１０４と、外部のＢＳＣ４０との通信インターフェースであって、非同期転送モード処理機能（ＡＴＭ処理機能）、ＡＴＭ Ａｄａｐｔａｔｉｏｎ Ｌａｙｅｒ ｔｙｐｅ２機能（ＡＡＬ２機能）、ＡＴＭ Ａｄａｐｔａｔｉｏｎ Ｌａｙｅｒ ｔｙｐｅ５機能（ＡＡＬ５機能）などを有し、伝送路から得られる情報を基に自身の動作クロックを生成する伝送路インターフェース部（ＢＳ−ＩＦ）１０５とから構成されている。送受信増幅部１０１には、送信ＲＦ信号を増幅する送信アンプと、受信ＲＦ信号を増幅する受信アンプと、ＲＦ送信信号とＲＦ受信信号とを分離または多重しアンテナ１００に接続する機能が備えられている。なお、このＢＳ２０以外のＢＳ、例えばＢＳ２ＮやＢＳ３０〜３Ｎなどの構成も同様である。
【００６５】
各ＢＳ２０〜２Ｎ、３０〜３Ｎ内部では、図９に示すような処理が行われる。
なおデータを受信する場合とデータを送信する場合とで処理が異なる。
【００６６】
例えばＢＳ２０などが受信物理チャネルで複数のタイムスロット＃１〜＃ｎのデータを受信すると、各タイムスロットのデータを組み立て、無線ユニットを生成する。続いて、無線ユニットに対してビットデインターリーブを行い、ビタビ復号化し、無線パケットヘッダ、データ、ＣＲＣ、ＴＡなどからなる無線パケットを生成し、ＣＲＣにより誤り訂正を行う。この後、データ部分を内符号化し、内符号化単位に分割し、データ、ＰＡＤ、トレイラなどからなる可変長パケットとする。
【００６７】
一方、ＢＳ２０がデータを送信する場合、可変長パケット内のデータを内符号化単位に結合し、無線パケットヘッダ、データ、ＣＲＣ、ＴＡなどからなる無線パケットを生成する。
【００６８】
続いて、無線パケットを畳み込み符号化してビットインターリーブを行い、無線ユニットを生成する。
【００６９】
この後、無線ユニットを複数のタイムスロットに分解して、送信物理チャネルの複数のタイムスロット＃１〜＃ｎにデータを載せて送信する。
【００７０】
上記ＢＳＣ４０などは、図１０に示すように、外部のＢＳ２０〜２ｎとの通信インターフェースであって、ＡＴＭ処理機能、ＡＡＬ２機能、ＡＡＬ５機能などを有する伝送路インターフェース部（ＢＳＣ−ＩＦ）２０１と、複数のＢＳ２０〜２ｎからのユーザデータと制御信号に対して選択合成を行う機能と複数のＢＳ２０〜２ｎに対してユーザデータ及び制御信号の分配を行う機能とを有し、ＭＳ１０〜１２などに対してダイバーシチハンドオーバ処理を行うダイバーシチハンドオーバ処理部（ＤＨＯ）２０２と、音声データの符号化／複合化およびその変換を行うコーデック部（ＣＯＤＥＣ）２０３と、主に無線回線制御、ＤＨＯ２０２に対する制御機能とＣＯＤＥＣ２０３に対する制御機能とを有する基地局制御局制御部（ＢＳＣ−ＣＮＴ）２０４と、このＢＳＣ−ＣＮＴ２０４からの命令に従って、上記各部、つまりＢＳＣ−ＩＦ２０１、ＤＨＯ２０２、ＣＯＤＥＣ２０３、ＢＳＣ−ＣＮＴ２０４間を送受されるユーザ情報および制御情報などのスイッチングを行う無線基地制御局スイッチ部（ＢＳＣ−ＳＷ）２０５とから構成されている。なお、ＢＳＣ４１の構成はＢＳＣ４０と接続先が異なるだけであり同様である。
【００７１】
ＭＳＣ５０は、図１１に示したように、音声データの符号化／復号化およびその変換を行うコーデック部（ＣＯＤＥＣ）３０１と、ユーザデータの信号処理機能を有し、パケット処理やモデムの再送処理などを行うアダプタ部（ＡＤＰ）３０２と、音声のアナログ信号とＰＣＭ信号の変換機能を有し、バックボーン網６０とのインターフェース機能を有する外部インターフェース部（ＥＸ−ＩＦ）３０３と、交換制御機能、呼制御機能およびＡＤＰ３０２に対する制御機能などを有する移動交換局制御部（ＭＳＣ一ＣＮＴ）３０４と、このＭＳＣ−ＣＮＴ３０４からの命令に従い、ＡＤＰ３０２、ＥＸ−ＩＦ３０３間のスイッチングを行う機能を有し、ユーザデータ及び制御情報をスイッチングする移動交換局スイッチ部（ＭＳＣ−ＳＷ）３０５とから構成されている。なお、ＭＳＣ５１の構成はＭＳＣ５０と接続先が異なるだけであり同様である。
【００７２】
バックボーン網６０はＭＳＣ５０、５１、固定端末７０、電話端末７１などを相互に接続し、データ、音声などの通信を実現するスイッチング、ルーティング機能を有するＡＴＭ交換網、ＩＳＤＮ、インターネットなどである。
【００７３】
固定端末７０はバックボーン網６０に接続され、少なくともＭＳ１０〜１２との間でＩＰパケットを用いてデータ通信を行うことができる端末である。
【００７４】
この固定端末７０とＭＳ１０〜１２との間のＩＰパケット伝送は、ＭＳＣ５０、５１、ＢＳＣ４０、４１、さらにＢＳ２０〜２Ｎ、３０〜３Ｎを経由して行われ、ＭＳ１０〜１２が上記のどのＢＳのサービスエリア内に移動しても通信を継続して行うことが可能である。
【００７５】
電話端末７１はバックボーン網７１と接続されており、少なくともＭＳ１０〜１２との間で音声通信を行うことができる端末である。この電話端末７１とＭＳ１０〜１２との間の音声伝送は、ＭＳＣ５０、５１、ＢＳＣ４０、４１、さらにＢＳ２０〜２Ｎ、３０〜３Ｎを経由して行われ、ＭＳ１０〜１２が上記のどのＢＳ２０〜２Ｎ、３０〜３Ｎのサービスエリア内に移動しても通信を継続して行うことが可能である。
【００７６】
この第２の実施形態のＣＤＭＡ通信システムにおいて、無線インターフェースの物理チャネルは、図１２、図１３に示すような構成であり、以下のように論理チャネルとマッピングされる。
【００７７】
すなわち、図１２に示す物理チャネルは、連続する複数のスーパーフレームから構成されている。各スーパーフレームは複数の無線フレームから構成されている。各無線フレームは複数のタイムスロットから構成されている。
【００７８】
各無線フレームの構成としては、スロット構成１、スロット構成２、スロット構成３の３つのスロットの中の少なくとも一つがあるような構成をとる。
【００７９】
スロット構成１としては無線フレーム内のスロット構成がｍ個の個別チャネル用スロットとｎ個の共有チャネル用スロットとに時間的に分割されている。
【００８０】
スロット構成２としては無線フレーム内のスロット構成がすべて個別チャネル用スロット（ｍ＋ｎ個）として定義されている。
【００８１】
スロット構成３としては無線フレーム内のスロット構成がすべて共有チャネル用スロット（ｍ＋ｎ個）として定義されている。
【００８２】
ＢＣＣＨ、ＦＡＣＨ、ＰＣＨ、ＲＡＣＨはスロット構成３にマッピングされている。ＳＤＣＣＨ、ＡＣＣＨ、ＤＴＣＨ、一部のＵＰＣＨはスロット構成２にマッピングされている。ＵＰＣＨの一部はスロット構成１にマッピングされている。 さらに、ＢＣＣＨ、ＦＡＣＨ、ＰＣＨ、ＲＡＣＨはサービスクラス１にマッピングされている。ＳＤＣＣＨ、ＡＣＣＨ、ＤＴＣＨ）一部のＵＰＣＨはサービスクラス２にマッピングされている。ＵＰＣＦＩの一部はサービスクラス３にマッピングされている。
【００８３】
また、図１３に示す物理チャネルは、連続する複数のスーパーフレームから構成されている。各スーパーフレームは複数の無線フレームから構成されている。各スーパーフレームの構成としては、フレーム構成１とフレーム構成２の２つのフレームの双方またはいずれか一方があるような構成をとる。フレーム構成１は、ｐ個の個別チャネル用フレームとｑ個の共有チャネル用フレ一ムとが別個に定義、つまり時間的に分割されているフレームである。フレーム構成２は、各無線フレーム毎に個別チャネル用フレームまたは共有チャネル用フレームのいずれか一方が定義されており、各フレームが任意に時間的に分割されて混在しているフレームである。
【００８４】
つまり、各スーパーフレームはフレーム構成１とフレーム構成２とのいずれか一方または双方があるような個別チャネル用フレームと共有チャネル用フレームとが混在した物理チャネル構成をとる。
【００８５】
ＢＣＣＨ、ＦＡＣＨ、ＰＣＨ、ＲＡＣＨ、ＵＰＣＨの一部はフレーム構成１またフレーム構成２の共有チャネル用フレームにマッピングされている。
【００８６】
ＳＤＣＣＨ、ＡＣＣＨ、ＤＴＣＨ、一部のＵＰＣＨはフレーム構成１またはフレーム構成２の個別チャネル用フレ一ムにマッピングされている。
【００８７】
ＢＣＣＨ、ＦＡＣＨ、ＰＣＨ、ＲＡＣＨはサービスクラス１にマッピングされている。ＳＤＣＣＨ、ＡＣＣＨ、ＤＴＣＨ、一部のＵＰＣＨはサービスクラス２にマッピングされている。ＵＰＣＨの一部はサービスクラス３にマッピングされている。
【００８８】
ここで、図１４、図１５を参照し、より具体的な物理チャネルと論理チャネルとのマッピングについて説明する。
【００８９】
これら図１４、図１５では、図１２のタイムスロットまたは図１３の無線フレーム数が８個ある場合の例を示している。
【００９０】
図１４に示すように、上りの物理チャネルと論理チャネルとのマッピングは、各ＢＳ２０〜２Ｎ、３０〜３Ｎの無線インターフェースにおいて、ＲＡＣＨに割り当てられたキャリア２ａのコード＃Ａ１のフレーム番号１〜８はすべて共通制御チャネルである。ＳＤＣＣＨに割り当てられたキャリア２ａのコード＃Ｂ１〜Ｂｎのフレーム番号１〜８はすべて個別制御チャネルである。ＤＴＣＨに割り当てられたキャリア２ｂのコード＃５１〜５ｍのフレーム番号１〜８、キャリア２ｃのコード＃６１〜６ｍのフレーム番号１〜４はすべてＣＯ型通信の個別通信チャネルである。ＵＰＣＨに割り当てられたキャリア２ｂのコード＃５１〜５ｍのフレーム番号１〜８はすべてＣＬ型通信の個別通信チャネル、キャリア２ｃのコード＃６１〜６ｍのフレーム番号５〜８はすべてＣＬ型通信の共通通信チャネルである。
【００９１】
また、図１５に示すように、下りの物理チャネルと論理チャネルとのマッピングは、各ＢＳ２０〜２Ｎ、３０〜３Ｎの無線インターフェースにおいて、ＢＣＣＨに割り当てられたキャリア１ａのコード＃１１のフレーム番号１〜８は、すべて共通制御チャネルである。またＰＣＨに割り当てられたキャリア１ａのコード＃２１のフレーム番号１〜８は、すべて共通制御チャネルである。ＦＡＣＨに割り当てられたキャリア１ａのコード＃３１のフレーム番号１〜８は、すべて共通制御チヤネルである。ＳＤＣＣＨに割り当てられたキャリア１ａのコード４１〜４ｍのフレーム番号１〜８は、すべて個別制御チャネルである。ＤＴＣＨに割り当てられたキャリア１ｂのコード＃４１〜４ｍのフレーム番号１〜８は、キャリア１ｃのコード＃５１〜５ｍのフレーム番号１〜４は、すべてＣＯ型通信の個別通信チャネルである。ＵＰＣＨに割り当てられたキャリア１ｂのコード＃４１〜４ｍのフレーム番号１〜８は、すべてＣＬ型通信の個別通信チャネルで、キャリア１ｃのコード＃５１〜５ｍのフレーム番号５〜８は、すべてＣＬ型通信の共通通信チャネルである。
【００９２】
図１２，図１３に示した物理チャネルの例は、スロットレベルまたはフレームレベルで個別チャネルと共通チャネルとが時間的または周波数的に分割された構成となっており、上述した第１の実施形態と同様の手法により、ＭＳ１０〜１２とＢＳ２０〜２Ｎ、３０〜３Ｎ間で送受信されるデータの通信品質に応じてコード多重数を別々に管理することにより、第１の実施形態と同様の効果を得ることができる。
【００９３】
また、上記第１および第２の実施形態では、ＭＳとＢＳ間で送受信されるデータの通信品質に応じて（サービスクラス毎に）コード多重数を時間的または／及び周波数的に完全に分割された物理チャネルの構成を示したが、必ずしも完全に分離されていなくても良い。
【００９４】
例えば異なるサービスクラスと時間的またはキャリアとしてオーバーラップされるような構成でも良く、この場合、サービスクラス毎にコード多重数を管理することにより、上記各実施形態と同様の効果を得ることができる。なお、この場合、そのサービスクラスの物理チャネルに対しては、図７に示したようなインターリーブなどを併用して用いることにより、同一サービスクラス内で時間的に不均一である通信品質を一様化することができる。
【００９５】
また、この他、例えばチャネル割り当ての際に、多重の低いフレーム、スロットから順番にチャネル割当てを行うことや、共通チャネルと個別チャネルとが時間的に重なっているスロット、フレームはなるべく個別チャネル割り当てには使用せずに、ハンドオフ時などのチャネル不足時に通信品質が多少劣化しても構わないときなどの割り当てに用いることなどが考えられる。さらに、上り／下りのチャネルの多重数管理を別々に行うことなども考えられる。
【００９６】
【発明の効果】
以上説明したように本発明によれば、個別チャネルにアクセスされるコード多重数の管理と、共通チャネルにアクセスされるコード多重数の管理とを別々に行うことにより、符号分割多元接続方式で無線通信を行う上で通信品質の異なるマルチメディア通信を効率良く行うことができる。
【図面の簡単な説明】
【図１】本発明のＣＤＭＡ通信システムの第１の実施形態の構成を示す図。
【図２】第１の実施形態のＣＤＭＡ通信システムの無線回線の論理チャネル構成を示す図。
【図３】第１の実施形態のＣＤＭＡ通信システムの無線回線の物理チャネルの第１の構成を示す図。
【図４】第１の実施形態のＣＤＭＡ通信システムの無線回線の物理チャネルの第２の構成を示す図。
【図５】タイムスロットレベルでサービスクラスが分割されている例を示す図。
【図６】無線フレームレベルでサービスクラスが分割されている例を示す図。
【図７】本発明のＣＤＭＡ通信システムの第２の実施形態の構成を示す図。
【図８】第２の実施形態のＣＤＭＡ通信システムのＢＳの構成を示す図。
【図９】第２の実施形態のＣＤＭＡ通信システムのＢＳの内部処理を示す図。
【図１０】第２の実施形態のＣＤＭＡ通信システムのＢＳＣの構成を示す図。
【図１１】第２の実施形態のＣＤＭＡ通信システムのＭＳＣの構成を示す図。
【図１２】第２の実施形態のＣＤＭＡ通信システムにおいて、各タイムスロット毎に定義した物理チャネルを示す図。
【図１３】第２の実施形態のＣＤＭＡ通信システムにおいて、各フレーム毎に定義した物理チャネルを示す図。
【図１４】第２の実施形態のＣＤＭＡ通信システムの上り物理チャネルと論理チャネルのマッピング例を示す図。
【図１５】第２の実施形態のＣＤＭＡ通信システムの下り物理チャネルと論理チャネルのマッピング例を示す図。
【図１６】従来のＣＤＭＡ通信システムにおいて、上り送信パケットがＢＳに集中する様子を示す図。
【図１７】従来のＣＤＭＡ通信システムにおける多重数の管理の様子を示す図。
【符号の説明】
１，２…無線端末（ＭＳ）、３…無線基地局（ＢＳ）、１０〜１２…無線端末（ＭＳ）、２０〜２Ｎ、３０〜３Ｎ…無線基地局（ＢＳ）、４０，４１…無線基地局制御局（ＢＳＣ）、５０，５１…移動交換局（ＭＳＣ）、６０…バックボーン網、７０…固定端末、７１…電話端末。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a code division multiple access (CDMA) communication system, a radio base station, To the bureau Related.
[0002]
[Prior art]
As a communication system capable of increasing user capacity and improving communication quality, there is a next-generation mobile communication system. In this next-generation mobile communication system, a code division multiple access (Code Division Multiple Access) is used as a wireless transmission system. (Hereinafter abbreviated as CDMA).
[0003]
In this CDMA system, a specific code is assigned to each radio line, and a modulated wave of the same carrier frequency is spread by this code and transmitted. On the receiving side, code synchronization is performed and a desired radio line is identified. This is the multiple access method.
[0004]
This CDMA system is different from a system adopted in PHS or the like, that is, a time division multiple access (hereinafter, referred to as TDMA), and a code for a radio base station to identify a radio terminal is determined in advance. As long as the wireless terminal wants to access, there is an advantage that the wireless base station can always access and communicate with the wireless base station, that is, it is possible to communicate directly for each call, and there is also an advantage of being excellent in confidentiality and interference resistance.
[0005]
As a mode of realizing the wireless communication system using the CDMA system, for example, a mode as shown in FIG. 16 can be considered.
[0006]
That is, this is a case where a large number of wireless terminals such as the mobile terminals MS1 and MS4 and the fixed terminals MS2 and MS3 exist within the service area controlled by one wireless base station BS. The wireless terminals called mobile terminals MS1 and MS4 are usually portable wireless telephones mainly carried by a person, and the fixed terminals MS2 and MS3 are those in which a wireless adapter for data communication is attached to a personal computer. In many cases, data communication is mainly performed. In general, a wireless telephone is a communication mode involving call setting, that is, a connection-oriented communication (CO-type communication), and a personal computer is a communication mode not involving the CO-type communication or call setting, a connectionless communication (CL-type communication). ) Is also possible, and in this case, different communication qualities are mixed. As described above, when a plurality of wireless terminals performing multimedia communication with different communication qualities such as CO-type communication and CL-type communication are accommodated in one wireless base station, as shown in FIG. Even if a communication channel (code) is allocated, if the number of multiplexed codes increases, all communication quality gradually deteriorates, and if the number of multiplexed codes exceeds a certain level, communication becomes impossible. is there.
[0007]
Therefore, in order to accommodate a plurality of wireless terminals performing multimedia communication having different communication qualities in a single wireless base station, the number of code multiplexes is adjusted to the limit multiplex number of traffic, which requires the highest communication quality. There is a need.
[0008]
However, in this case, the radio base station must set a threshold value with a considerable margin in advance, and the user capacity may not be increased as expected.
[0009]
[Problems to be solved by the invention]
As described above, the conventional CDMA communication system can efficiently accommodate users when accommodating traffic having a uniform communication quality, but in a multimedia communication environment in which different communication qualities coexist, the code can be improved. Since it is necessary to match the multiplexing number to the limit multiplexing number of the traffic that requires the highest communication quality, there is a problem that the user capacity does not increase as expected and the communication efficiency decreases in multimedia communication. .
[0010]
The present invention has been made to solve such a problem, and a communication system and a wireless base station capable of efficiently performing multimedia communication with different communication quality when performing wireless communication in a CDMA system. Station It is intended to provide.
[0012]
[Means for Solving the Problems]
In order to achieve the above object, a communication system according to the present invention has at least one or more radio terminals and a radio base station that transmits and receives data to and from the radio terminals by a code division multiple access method. In the system, the physical channel of the wireless line for transmitting and receiving the data, a common channel that is commonly accessed from the one or more wireless terminals, and divided into individual channels that one wireless terminal accesses exclusively, Management of the number of code multiplexes accessed to the dedicated channel and management of the number of code multiplexes accessed to the common channel are separately performed. And generates access permission probability information for each service class of transmission information of a wireless terminal that wants to start communication. It is characterized by:
[0013]
3. The radio base station according to claim 2, wherein the radio base station transmits and receives data to and / or from at least one or more radio terminals by a code division multiple access scheme. A wireless channel having a physical channel divided into an individual channel exclusively accessed by one wireless terminal, a management of the number of code multiplexes by which the wireless terminal accesses the individual channel, and the wireless terminal To manage the number of code multiplexes to access And generates access permission probability information for each service class of transmission information of a wireless terminal that wants to start communication. It is characterized by:
[0017]
Claim 1 In the case of the described invention, the management of the number of multiplexed codes of the individual channel and the management of the number of multiplexed codes of the common channel are separately performed on the system side, so that multimedia having different communication qualities in performing wireless communication by the CDMA system is provided. Communication can be performed efficiently.
[0018]
Claim 2 In the case of the described invention, the wireless base station separately manages the number of code multiplexes in which the wireless terminal accesses the dedicated channel and manages the number of code multiplexes in which the wireless terminal accesses the common channel. In performing communication, multimedia communication with different communication quality can be performed efficiently.
[0020]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0021]
FIG. 1 is a diagram showing a configuration of a CDMA communication system according to a first embodiment of the present invention.
[0022]
As shown in FIG. 1, the CDMA communication system according to the first embodiment includes at least one wireless terminal 1 or 2 (hereinafter referred to as MS 1 or 2) and a wireless base station 3 (hereinafter referred to as BS 3). It has been done. The BS 3 and the MSs 1 and 2 existing in the service area transmit and receive data via a radio channel (hereinafter referred to as a CDMA radio channel) based on a code division multiple access system.
[0023]
The MSs 1 and 2 are terminals that transmit and receive data to and from the BS 3 using a code channel via a CDMA wireless line. These MSs 1 and 2 are terminals capable of performing at least connectionless communication such as IP packets (hereinafter referred to as CL-type communication) and also performing connection-oriented communication such as voice data (hereinafter referred to as CO-type communication). .
[0024]
The BS 3 is a device that accommodates at least one or more MSs 1 and 2 and that transmits and receives data using a code channel via a CDMA radio line. CL-type communication such as an IP packet and CO-type communication such as voice are performed between the BS 3 and the MSs 1 and 2.
[0025]
The radio interface between the BS 3 and the MSs 1 and 2 is shown in FIGS. 3 to 6 in which a logical channel as shown in FIG. 2 and each code are temporally divided into communication quality numbers (number of different service classes). Such a physical channel is defined.
[0026]
The logical channel shown in FIG. 2 includes a control channel (CCH: Control Channel) used for transmitting and receiving control information and a communication channel (TCH: Traffic Channel) used for transmitting and receiving user information. TCH is a bidirectional or downlink / uplink unidirectional channel for carrying user information, and is a communication channel (DTCH: Dedicated Traffic) used for communicating real-time user information (mainly data of CO type communication) such as voice. Channel), and a user packet channel (UPCH) for transmitting and receiving packet data information on a bidirectional or uplink / downlink unidirectional channel for carrying user information. The packet data information is mainly data of CO type communication, but may include data information of CL type communication, or may include control information defined by a user.
[0027]
The CCH includes a common control channel (CCCH), which is a point-multipoint control channel that carries a connectionless message, and a dedicated control channel (DCCH), which is a point-to-point bidirectional control channel. It is composed of
[0028]
The CCCH is a channel used to broadcast information to the wireless terminal. The CCCH is received before the wireless terminal accesses the network, and is received by a network number, a wireless base station number, a sector number, a location registration area number, a perch channel number, and a stop. Broadcast control channel (BCCH), which is a point-multipoint downlink unidirectional common control channel for acquiring system information such as tree channel numbers, regulation information, control channel structure information, and extended information elements, and call establishment A random access channel (RACH), which is an uplink unidirectional common control channel that carries messages such as requests and responses to network inquiries, and carries messages such as inquiries to radio terminals and radio-related resource allocation ( Packet data information A forward access channel (FACH), which is a downlink unidirectional common control channel, and a downlink unidirectional common control channel used for paging of wireless terminals at the time of wireless terminal termination connection. And a paging channel (PCH).
[0029]
The DCCH is always allocated together with a dedicated control channel (SDCCH: Stand alone Dedicated Control Channel), which is a dedicated control channel in a point-to-point direction used for allocating the TCH, etc. (along with the UPCH as necessary) (Associated Control Channel), which is a dedicated point-to-point bidirectional control channel.
[0030]
The physical channels shown in FIGS. 3 and 4 have a configuration of a downlink common control channel (BCCH, PCH, FACH). In the example of FIG. 3, one superframe is composed of a plurality of radio frames (frame # 1 to frame # (L + M + N)). One radio frame is composed of a plurality of time slots # 1 to # (l + m + n). In this example, BCCH, PCH, and FACH are multiplexed (mixed) for each time slot.
[0031]
In the example of FIG. 4, one superframe is composed of a plurality of radio frames (frame # 1 to frame # (L + M + N)). One radio frame is composed of a plurality of time slots # 1 to # (l + m + n). In this example, BCCH, PCH, and FACH are multiplexed (mixed) for each radio frame, and BCCH, PCH, and FACH are multiplexed (mixed) for each time slot.
[0032]
The physical channel may have a configuration in which BCCH, PCH, and FACH are multiplexed (mixed) at a time slot level or a radio frame level, for example, in addition to the above. Although not shown, the physical channel may have a configuration in which BCCH, PCH, and FACH are multiplexed at a superframe level (a configuration in which BCCH, PCH, and FACH can always be transmitted).
[0033]
The physical channels shown in FIGS. 5 and 6 are divided into three different service classes such as service class 1, service class 2, and service class 3 in time or carrier.
(Frequency). The service class 1 is a service class for highly reliable / high communication quality assurance CL-type communication such as communication of control information by random access. The service class 2 is a service class for performing CO-type communication such as voice communication for guaranteeing communication quality such as delay. The service class 3 is a service class for performing Best Effort type CL communication such as packet communication.
[0034]
FIG. 5 shows an example in which a physical channel is divided into a plurality of service classes at a time slot level, and FIG. 6 shows an example in which a physical channel is divided into a plurality of service classes at a radio frame level. Each RACH is mapped to service class 1. The SDCCH, ACCH, DTCH, and some UPCHs are mapped to service class 2. Part of the UPCH is mapped to service class 3.
[0035]
In this CDMA communication system, when the MSs 1 and 2 perform CO-type communication such as voice communication with the BS 3, the BS 3 individually assigns codes to the MSs 1 and 2, and each of the MSs 1 and 2 uses a code assigned by the BS 3. Send data.
[0036]
The BS 3 separately manages the number of multiplexes for each of the service classes 1, 2, and 3. When the MSs 1 and 2 perform CL-type communication of, for example, packets, the MSs 1 and 2 do not transmit packets without restriction. As described above, the BS 3 notifies the MSs 1 and 2 of the transmission permission probability information for each of the service classes 1, 2 and 3.
[0037]
The MSs 1 and 2 transmit data using codes commonly assigned to the MSs 1 and 2 based on the transmission permission probability information broadcast from the BS 3.
[0038]
On the other hand, when performing CL-type communication, for example, the MSs 1 and 2 transmit packets based on transmission permission probability information for each of the service classes 1, 2 and 3.
[0039]
This allows the BS 3 to manage the number of multiplexes for each of the service classes 1, 2, 3 so as to be kept below the set threshold value.
[0040]
Hereinafter, an operation when performing voice communication such as telephone communication and data communication such as packet communication and a multiplexing management method at that time will be described more specifically. Note that the operation at the time of performing packet communication includes the operation of communication of control information by random access.
[0041]
The MSs 1 and 2 first receive system-related information such as a channel structure broadcast periodically using the BCCH from the BS 3, and operate based on the received broadcast information.
[0042]
Here, the operation at the time of voice transmission will be described first as the operation at the time of voice communication.
[0043]
When the MSs 1 and 2 perform voice transmission, a call setup is performed using the RACH and FACH of the service class 1 and the SDCCH of the service class 2, so that the dedicated channel (DTCH) of the service class 2 is allocated from the BS 3. Thus, data communication between each other becomes possible.
[0044]
At this time, when the MSs 1 and 2 perform random access using the RACH, they transmit packets based on the transmission permission probability information of the service class 1 periodically broadcast from the BS 3 using the BCCH or the like. Thereby, the BS 3 can manage the number of multiplexes so as to satisfy the communication quality of the service class 1.
[0045]
On the other hand, when the MS1 and MS2 receive voice, if there is a call from the BS3 to the MS1 or MS2 based on the PCH, the MS1 or MS2 responds to the BS3 using the RACH of the service class 1. Then, the dedicated channel (DTCH) of the service class 2 is allocated by the BS 3 using the SDCCH of the service class 2 and the like, and data communication becomes possible between each other.
[0046]
At this time, when the MSs 1 and 2 perform random access using the RACH, they transmit packets based on the transmission permission probability information of the service class 1 as in the case of voice transmission. Next, an operation at the time of packet transmission will be described as an operation at the time of packet communication. When the MSs 1 and 2 perform packet transmission, they select either the service class 2 or the service class 3 UPCH to be used in accordance with the communication quality required for packet communication, and preliminarily select the service class for the selected service class. A code is randomly selected from the assigned code group and the packet is transmitted.
[0047]
At this time, when the MSs 1 and 2 perform random access using the UPCH, the MSs 1 and 2 are based on the transmission permission probability information of the service class 2 or the service class 3 periodically broadcast from the BS 3 using the BCCH or the like. Send a packet.
[0048]
Here, as for the UPCH of the service class 2, call setup is performed using the RACH and FACH of the service class 1 and the SDCCH of the service class 2 as necessary, as in the case of voice transmission. Then, the UPCH is allocated by the BS 3 as a dedicated channel of the service class 2, and communication becomes possible.
[0049]
On the other hand, when the MSs 1 and 2 receive the packet, if there is a call to the MSs 1 and 2 based on the PCH from the BS 3, the MSs 1 and 2 respond to the incoming call on the RACH of the service class 1. Then, the BS3 is assigned a service class 2 UPCH (dedicated channel) or a service class 3 UPCH (shared channel) using the FACH. Thereby, the MSs 1 and 2 receive the packet based on the assigned UPCH.
[0050]
Here, the allocation of the UPCH at the time of packet reception may be performed using the RACH and the FACH as described above, or the UPCH (code) for packet reception may be allocated on the PCH.
[0051]
With such a configuration, there is an advantage that random access required for allocating a channel for packet reception can be reduced.
[0052]
Also, instead of calling by PCH, a paging channel dedicated to packet communication is defined as one of the UPCHs, and the UPCH for calling is used during packet communication to allocate a UPCH for calling or / and receiving a packet. Is also good.
[0053]
More specifically, a method of managing the number of code multiplexes when RACH and UPCH are mixed in uplink communication packets of CO communication when transmitting packets of CL communication will be described more specifically.
[0054]
The transmission permission probability information for each service class is periodically broadcast from the BS 3 to the MSs 1 and 2.
[0055]
If there is CL-type communication information to be transmitted, the MSs 1 and 2 transmit packets based on the transmission permission probability PAi of the service class i of the information to be transmitted received at that time.
[0056]
The BS 3 calculates the transmission permission probability for each service class i by the next broadcast timing (during Δt) based on the following calculation formula, and sends the updated transmission permission probability to the MS 1 and MS 2. Operate to notify.
[0057]

In this way, the BS 3 recalculates the transmission permission probability for each service class i by the next timing and notifies the MS 1 and 2 of the updated transmission permission probability.
[0058]
That is, data is transmitted and received between the MS 1 and the BS 3 in a configuration in which the physical channel configuration of the radio interface between the MS 1 and the BS 2 and the BS 3 is temporally divided into a plurality of service classes at the time slot level or the radio frame level. In this case, the data is mapped to a desired service class according to the communication quality. Therefore, if the MSs 1 and 2 operate based on the transmission permission probability information for each service class broadcast from the BS 3, the data transmission / reception amount at this time (Code multiplex number) can be managed on the BS3 side.
[0059]
As described above, according to the CDMA communication system of the first embodiment, since the number of code multiplexes is divided and managed in accordance with the communication quality of data transmitted and received between the MS 1 and the MS 2 and the BS 3, the channel with the strictest required quality is The number of multiplexes is not limited. This is because the number of multiplexed codes in the service class channel with less demanding quality is managed by changing the number of multiplexing in accordance with the communication quality, such as by increasing the number of code multiplexing in the channel of service class with strict request quality. Thus, the number of terminals accommodated in one BS3 can be increased. In particular, if the number of multiplexed user packets in the Best Effort CL-type communication such as packet communication is increased, the terminals can be accommodated efficiently.
[0060]
In addition, by dividing and managing the number of code multiplexes according to the communication quality of data, when access is concentrated on a shared channel used for transferring user packets of the Best Effort CL-type communication such as packet communication. Also, it is possible to maintain the communication quality of a dedicated channel mainly used for a shared channel for control, CO-type communication, or the like at or above a desired value.
As a result, a CDMA communication system with high channel utilization efficiency can be realized.
[0061]
Next, a second embodiment of the CDMA communication system according to the present invention will be described with reference to FIG. FIG. 7 is a diagram showing the configuration of the second embodiment of the CDMA communication system according to the present invention.
[0062]
As shown in FIG. 7, the CDMA communication system includes radio terminals 10 to 12 (hereinafter, referred to as MSs 10 to 12), radio base stations 20 to 2N, 30 to 3N (hereinafter, BSs 20 to 2N, and BSs 30 to 3N), It is composed of radio base station control stations 40 and 41 (hereinafter referred to as BSCs 40 and 41), mobile switching centers 50 and 51 (hereinafter referred to as MSCs 50 and 51), a backbone network 60, a fixed terminal 70, a telephone terminal 71, and the like.
[0063]
The fixed terminal 70, the MSCs 50 and 51, and the like are connected to the backbone network 60. The BSC 40 is connected to the MSC 50. The BSs 20 to 2N are connected to the BSC 40. The BSC 41 is connected to the MSC 51. The BSs 30 to 3N are connected to the BSC 41. Each of the BSs 20 to 2N and 30 to 3N establishes a wireless line with the MS 10 to 12 existing in the service area of its own station, and performs data transmission and reception between the fixed terminal 70 and the MS 10 to 12. At this time, the above-described logical channel as shown in FIG. 3 is defined in the interface of the wireless line. The MSs 10 to 12 are terminals that transmit and receive data by establishing a wireless line with any one of the BSs 20 to 2N and 30 to 3N. These MSs 10 to 12 are terminals capable of performing at least CL-type communication such as IP packets and CO-type communication such as voice.
[0064]
For example, as shown in FIG. 8, the BS 20 transmits and receives RF signals using a plurality of antennas 100, and separates and multiplexes an RF transmission signal and an RF reception signal using the antennas 100 and connects to the plurality of antennas 100. The transmission / reception amplification unit (AMP) 101 detects the RF reception signal output from the reception amplifier of the transmission / reception amplification unit (AMP) 101, and performs A / D conversion to the baseband signal processing unit (BB) 103. A radio unit (TR) 102 that performs D / A conversion of a transmission signal subjected to baseband spreading by a baseband signal processing unit (BB) 103 and converts the transmission signal into an RF transmission signal by quadrature modulation, and an error correction of transmission data. Coding, framing, data modulation, spreading modulation and despreading of received signal, chip synchronization, error decoding, data demultiplexing, inter-sector handover Base station signal processing section 103 which performs base band signal processing such as maximum ratio combining at the time, and base station control section which transmits and receives control signals to and from BSC 40 and MSC 50, and performs radio line management, setting and release of radio lines, etc. (It is a communication interface between the BTC-CNT 104 and the external BSC 40 and has an asynchronous transfer mode processing function (ATM processing function), an ATM adaptation layer type 2 function (AAL2 function), an ATM adaptation layer type 5 function (AAL5 function), and the like. And a transmission line interface (BS-IF) 105 for generating its own operation clock based on information obtained from the transmission line.The transmission / reception amplification unit 101 includes a transmission amplifier for amplifying a transmission RF signal. And a reception amplifier that amplifies the reception RF signal. And flop, the ability to connect to the RF transmission signal and the RF reception signal and the separated or multiple antennas 100 are provided. In addition, BS other than the BS20, is the same configuration, such as for example BS2N and BS30～3N.
[0065]
The processing as shown in FIG. 9 is performed inside each of the BSs 20 to 2N and 30 to 3N.
Note that processing differs between the case of receiving data and the case of transmitting data.
[0066]
For example, when the BS 20 or the like receives data of a plurality of time slots # 1 to #n on a reception physical channel, it assembles data of each time slot to generate a wireless unit. Subsequently, the wireless unit performs bit deinterleaving, performs Viterbi decoding, generates a wireless packet including a wireless packet header, data, CRC, TA, and the like, and performs error correction using the CRC. Thereafter, the data portion is inner-coded and divided into inner-coding units to obtain a variable-length packet including data, a PAD, a trailer, and the like.
[0067]
On the other hand, when transmitting data, the BS 20 combines the data in the variable length packet into inner coding units to generate a wireless packet including a wireless packet header, data, CRC, TA, and the like.
[0068]
Subsequently, the wireless packet is convolutionally coded and bit interleaved to generate a wireless unit.
[0069]
Thereafter, the wireless unit is decomposed into a plurality of time slots, and data is transmitted in a plurality of time slots # 1 to #n of the transmission physical channel.
[0070]
As shown in FIG. 10, the BSC 40 and the like are communication interfaces with external BSs 20 to 2n, and include a transmission line interface (BSC-IF) 201 having an ATM processing function, an AAL2 function, an AAL5 function, and the like. Has a function of selectively combining user data and control signals from BSs 20 to 2n and a function of distributing user data and control signals to a plurality of BSs 20 to 2n. Diversity handover processing section (DHO) 202 for performing diversity handover processing, codec section (CODEC) 203 for performing encoding / decoding of voice data and conversion thereof, control function mainly for radio channel control, DHO 202, and control for CODEC 203 Base station control station control section (BSC-C T) 204 and a radio base station switching unit that performs switching of user information and control information transmitted and received between the BSC-IF 201, DHO 202, CODEC 203, and BSC-CNT 204 in accordance with instructions from the BSC-CNT 204. (BSC-SW) 205. The configuration of the BSC 41 is the same as that of the BSC 40 except that the connection destination is different.
[0071]
As shown in FIG. 11, the MSC 50 has a codec unit (CODEC) 301 for encoding / decoding and converting audio data and a signal processing function for user data, and performs packet processing, modem retransmission processing, and the like. (ADP) 302 which performs a conversion, an external interface (EX-IF) 303 which has a function of converting an analog signal of voice and a PCM signal and has an interface function with the backbone network 60, an exchange control function, and a call control A mobile switching center control unit (MSC-CNT) 304 having a function and a control function for the ADP 302, and a function of switching between the ADP 302 and the EX-IF 303 in accordance with an instruction from the MSC-CNT 304; Mobile switching center switch (MSC-SW) 3 for switching information And a 5. The configuration of the MSC 51 is the same as that of the MSC 50 except that the connection destination is different.
[0072]
The backbone network 60 connects the MSCs 50 and 51, the fixed terminal 70, the telephone terminal 71, and the like to each other, and is an ATM switching network having switching and routing functions for realizing communication of data, voice, etc., an ISDN, the Internet, and the like.
[0073]
The fixed terminal 70 is a terminal connected to the backbone network 60 and capable of performing data communication with at least the MSs 10 to 12 using IP packets.
[0074]
The IP packet transmission between the fixed terminal 70 and the MSs 10 to 12 is performed via the MSCs 50 and 51, the BSCs 40 and 41, and the BSs 20 to 2N and 30 to 3N. Communication can be continued even if the user moves into the area.
[0075]
The telephone terminal 71 is a terminal connected to the backbone network 71 and capable of performing voice communication with at least the MSs 10 to 12. The voice transmission between the telephone terminal 71 and the MSs 10 to 12 is performed via the MSCs 50 and 51, the BSCs 40 and 41, and the BSs 20 to 2N and 30 to 3N. It is possible to continue communication even if moving within the service area of 30 to 3N.
[0076]
In the CDMA communication system according to the second embodiment, the physical channels of the radio interface have a configuration as shown in FIGS. 12 and 13, and are mapped to logical channels as follows.
[0077]
That is, the physical channel shown in FIG. 12 is composed of a plurality of continuous superframes. Each superframe is composed of a plurality of radio frames. Each radio frame is composed of a plurality of time slots.
[0078]
The configuration of each radio frame is such that there is at least one of three slots, slot configuration 1, slot configuration 2, and slot configuration 3.
[0079]
As the slot configuration 1, the slot configuration in the radio frame is temporally divided into m individual channel slots and n shared channel slots.
[0080]
As the slot configuration 2, all slot configurations in the radio frame are defined as dedicated channel slots (m + n).
[0081]
As the slot configuration 3, all the slot configurations in the radio frame are defined as shared channel slots (m + n).
[0082]
BCCH, FACH, PCH, and RACH are mapped to slot configuration 3. SDCCH, ACCH, DTCH and some UPCH are mapped to slot configuration 2. Part of the UPCH is mapped to slot configuration 1. Further, BCCH, FACH, PCH, and RACH are mapped to service class 1. Some UPCHs are mapped to service class 2 (SDCCH, ACCH, DTCH). Part of the UPCFI is mapped to service class 3.
[0083]
Further, the physical channel shown in FIG. 13 is composed of a plurality of continuous superframes. Each superframe is composed of a plurality of radio frames. The configuration of each superframe is such that there is one or both of two frames, frame configuration 1 and frame configuration 2. Frame configuration 1 is a frame in which p individual channel frames and q shared channel frames are defined separately, that is, divided temporally. Frame configuration 2 is a frame in which either a dedicated channel frame or a shared channel frame is defined for each radio frame, and each frame is arbitrarily divided in time and mixed.
[0084]
In other words, each superframe has a physical channel configuration in which a dedicated channel frame and a shared channel frame in which one or both of the frame configurations 1 and 2 exist.
[0085]
Part of the BCCH, FACH, PCH, RACH, and UPCH are mapped to the shared channel frame of the frame configuration 1 or the frame configuration 2.
[0086]
The SDCCH, ACCH, DTCH, and some UPCHs are mapped to the dedicated channel frame of frame configuration 1 or frame configuration 2.
[0087]
BCCH, FACH, PCH, and RACH are mapped to service class 1. SDCCH, ACCH, DTCH and some UPCH are mapped to service class 2. Part of the UPCH is mapped to service class 3.
[0088]
Here, more specific mapping between physical channels and logical channels will be described with reference to FIGS.
[0089]
FIGS. 14 and 15 show an example in which the number of time slots in FIG. 12 or the number of radio frames in FIG. 13 is eight.
[0090]
As shown in FIG. 14, the mapping between the uplink physical channel and the logical channel is such that the frame numbers 1 to 8 of the code # A1 of the carrier 2a allocated to the RACH are assigned to the radio interfaces of the BSs 20 to 2N and 30 to 3N. All are common control channels. The frame numbers 1 to 8 of the codes # B1 to Bn of the carrier 2a allocated to the SDCCH are all dedicated control channels. The frame numbers 1 to 8 of the codes # 51 to 5m of the carrier 2b and the frame numbers 1 to 4 of the codes # 61 to 6m of the carrier 2c allocated to the DTCH are all dedicated communication channels for CO-type communication. Frame numbers 1 to 8 of codes # 51 to 5m of carrier 2b allocated to UPCH are all dedicated communication channels for CL-type communication, and frame numbers 5 to 8 of codes # 61 to 6m of carrier 2c are all common to CL-type communication. Communication channel.
[0091]
As shown in FIG. 15, the mapping between the downlink physical channel and the logical channel is performed on the radio interfaces of the BSs 20 to 2N and 30 to 3N in the frame numbers 1 to 1 of the code # 11 of the carrier 1a assigned to the BCCH. 8 are all common control channels. The frame numbers 1 to 8 of the code # 21 of the carrier 1a allocated to the PCH are all common control channels. The frame numbers 1 to 8 of the code # 31 of the carrier 1a assigned to the FACH are all common control channels. The frame numbers 1 to 8 of the codes 41 to 4m of the carrier 1a allocated to the SDCCH are all dedicated control channels. The frame numbers 1 to 8 of the codes # 41 to 4m of the carrier 1b assigned to the DTCH and the frame numbers 1 to 4 of the codes # 51 to 5m of the carrier 1c are all dedicated communication channels for CO-type communication. The frame numbers 1 to 8 of the codes # 41 to 4m of the carrier 1b allocated to the UPCH are all dedicated communication channels for CL-type communication, and the frame numbers 5 to 8 of the codes # 51 to 5m of the carrier 1c are all CL-type. This is a common communication channel for communication.
[0092]
The example of the physical channel shown in FIGS. 12 and 13 has a configuration in which an individual channel and a common channel are temporally or frequency-divided at a slot level or a frame level. The same effect as in the first embodiment can be obtained by separately managing the number of code multiplexes according to the communication quality of data transmitted and received between the MSs 10 to 12 and the BSs 20 to 2N and 30 to 3N by the same method. be able to.
[0093]
In the first and second embodiments, the number of code multiplexes is completely divided in time or / and frequency according to the communication quality of data transmitted / received between the MS and the BS (for each service class). Although the configuration of the physical channel has been shown, it is not always necessary to completely separate the physical channel.
[0094]
For example, a configuration may be adopted in which different service classes are overlapped temporally or as carriers. In this case, by managing the number of code multiplexes for each service class, the same effects as in the above embodiments can be obtained. In this case, for the physical channel of the service class, the inter-leave as shown in FIG. Can be
[0095]
In addition, for example, when allocating channels, channel allocation is performed in the order of low multiplexing frames and slots, and slots and frames in which a common channel and an individual channel temporally overlap are assigned to individual channel allocation as much as possible. Instead of using, it is conceivable to use it for assignment when the communication quality may be slightly degraded due to lack of channels such as during handoff. Furthermore, it is also conceivable to separately manage the number of multiplexed uplink / downlink channels.
[0096]
【The invention's effect】
According to the present invention as described above, ,Pieces By separately managing the number of code multiplexes accessed to different channels and managing the number of code multiplexes accessed to a common channel, multimedia having different communication qualities in performing wireless communication by the code division multiple access method Communication can be performed efficiently.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration of a CDMA communication system according to a first embodiment of the present invention.
FIG. 2 is a diagram showing a logical channel configuration of a wireless channel of the CDMA communication system according to the first embodiment.
FIG. 3 is a diagram showing a first configuration of a physical channel of a radio channel in the CDMA communication system according to the first embodiment.
FIG. 4 is a diagram showing a second configuration of a physical channel of a radio channel in the CDMA communication system according to the first embodiment.
FIG. 5 is a diagram showing an example in which a service class is divided at a time slot level.
FIG. 6 is a diagram showing an example in which a service class is divided at a radio frame level.
FIG. 7 is a diagram showing a configuration of a CDMA communication system according to a second embodiment of the present invention.
FIG. 8 is a diagram illustrating a configuration of a BS in the CDMA communication system according to the second embodiment;
FIG. 9 is an exemplary view showing internal processing of a BS in the CDMA communication system according to the second embodiment;
FIG. 10 is a diagram illustrating a configuration of a BSC of the CDMA communication system according to the second embodiment.
FIG. 11 is a diagram illustrating a configuration of an MSC in the CDMA communication system according to the second embodiment;
FIG. 12 is a diagram showing physical channels defined for each time slot in the CDMA communication system according to the second embodiment.
FIG. 13 is a diagram showing a physical channel defined for each frame in the CDMA communication system according to the second embodiment.
FIG. 14 is a diagram showing an example of mapping between uplink physical channels and logical channels in the CDMA communication system according to the second embodiment;
FIG. 15 is a diagram showing an example of mapping between a downlink physical channel and a logical channel in the CDMA communication system according to the second embodiment;
FIG. 16 is a diagram showing a state in which uplink transmission packets concentrate on a BS in a conventional CDMA communication system.
FIG. 17 is a diagram showing how a multiplex number is managed in a conventional CDMA communication system.
[Explanation of symbols]
1, 2 ... wireless terminal (MS), 3 ... wireless base station (BS), 10-12 ... wireless terminal (MS), 20-2N, 30-3N ... wireless base station (BS), 40, 41 ... wireless base Central control station (BSC), 50, 51: Mobile switching center (MSC), 60: Backbone network, 70: Fixed terminal, 71: Telephone terminal.

Claims (2)

In a communication system having at least one or more wireless terminals and a wireless base station that transmits and receives data by the wireless terminal and a code division multiple access method,
The physical channel of the wireless line for transmitting and receiving the data, a common channel that is commonly accessed from the one or more wireless terminals, and a dedicated channel that one wireless terminal accesses exclusively,
The management and number of multiplexed codes that are accessed dedicated channel have separate line management and the number of multiplexed codes to be accessed to the common channel,
A communication system characterized by generating access permission probability information for each service class of transmission information of a wireless terminal that wants to start communication. In a wireless base station that transmits and receives data by at least one or more wireless terminals and a code division multiple access method,
A wireless channel having a physical channel divided into a common channel commonly accessed by the one or more wireless terminals and an individual channel exclusively accessed by one wireless terminal is established, and the wireless terminal accesses the individual channel. management and number of multiplexed codes of the, have separate line management and the number of multiplexed codes of the wireless terminal accesses to the common channel,
A wireless base station that generates access permission probability information for each service class of transmission information of a wireless terminal that wants to start communication .

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