JP4205868B2

JP4205868B2 - Signal receiving apparatus in DS-CDMA system

Info

Publication number: JP4205868B2
Application number: JP2001064061A
Authority: JP
Inventors: 善生和田
Original assignee: Kenwood KK
Current assignee: Kenwood KK
Priority date: 2001-03-07
Filing date: 2001-03-07
Publication date: 2009-01-07
Anticipated expiration: 2021-03-07
Also published as: JP2002271233A

Description

【０００１】
【発明の属する技術分野】
本発明は、ＤＳ−ＣＤＭＡシステムにおける信号受信装置に関し、特に、マルチパスによる干渉によって受信性能の劣化を防止するものである。
【０００２】
【従来の技術】
ＤＳ−ＣＤＭＡ（Direct Sequence-Code Division Multiple Access ）システムとして、北米で標準化されたＣＤＭＡ方式セルラ電話システム（ＴＩＡＩＳ９５）がある。このシステムでは、下り回線（下りリンク）においてパイロットチャンネルにパイロットシンボルを挿入して送信し、受信側でこのパイロットチャンネルの受信信号に基づいてキャリア位相を検出して同期検波を行っている。しかし、このシステムでは、伝送レートが高速になると、観測されるマルチパス数が増加し、受信側の受信性能が劣化するという欠点がある。
【０００３】
このような欠点を解決するものとして、例えば、第２９３０５８５号特許公報に記載のマルチユーザ・マルチステージ型の干渉キャンセラを備えた信号受信装置がある。図４は、この信号受信装置の概略構成を示すブロック図である。
【０００４】
この信号受信装置では、まず、インパルスレスポンスを推定し、このインパルスレスポンスを表す基本信号を固定して、Ｒａｋｅ部１０２で出力データＤＲを検出する。また、図示しない電力最大パス検出器が前記基準信号に基づき電力が最大となるパスＰを選択する。電力が最大となるパスＰは、干渉成分を含む割合が少なく、パスＰを除くパスについては主に干渉成分であると推定される。そこで、干渉キャンセラ１０４−１においては、Ｒａｋｅ部１０２から出力されたデータを初期データとして、電力が最大となるパスＰ以外のパスにおける、同期検波および逆拡散を行う以前の信号を生成するとともに、パイロットチャンネルの既知のデータに基づいて、電力が最大となるパスＰ以外のパスにおける、逆拡散を行う以前のパイロットチャンネルの信号を生成して干渉レプリカとし、受信信号からその干渉レプリカを差し引いて、電力が最大のパスＰについて再び逆拡散および同期検波を行うことによりデータを再び検証しなおし、干渉成分がキャンセルされたより確からしいデータＤＣ（１）を出力する。
【０００５】
第２段目以降の干渉キャンセラについては、前段の干渉キャンセラからの出力データが次の段の干渉キャンセラの入力データとなるとともに、パイロットチャンネルの既知のデータも入力される。何れの段の干渉キャンセラも、前記電力最大パス検出器から出力される同じパスＰを電力最大パスとして選択する。
【０００６】
ある段の干渉キャンセラの出力データは、この干渉キャンセラの入力データよりも確からしくなる。その次の段の干渉キャンセラは、前段の干渉キャンセラの出力データを入力してさらに確からしい干渉レプリカを生成する。このさらに確からしい干渉レプリカによって、その段における干渉キャンセラの出力データはさらに確からしいものとなる。したがって、干渉キャンセラをＭ段カスケード接続して、Ｍ段目の干渉キャンセラ１０４−Ｍの出力データＤＣ（Ｍ）を最終出力とすることにより、検出データの精度を向上させることができる。
【０００７】
【発明が解決しようとする課題】
このように、図４に示した従来の信号受信装置では、干渉キャンセラの段数が増えるにつれ、干渉レプリカを生成する精度が向上し、検出データの精度を向上させることができる。しかし、その反面で、各干渉キャンセラからの出力データの精度にばらつきがある。すなわち、各干渉キャンセラは同じ割合で干渉成分を除去してデータを出力することはできないため、最終段の干渉キャンセラから出力されるデータの精度は向上しているものの、まだ若干の干渉成分を含んでいることは否めない。
【０００８】
そこで、本発明は、上記のような従来技術の有する問題点に鑑みなされたものであり、その目的は、マルチパスの相互相関による干渉を高い割合で除去し、より一層受信性能が向上したＤＳ−ＣＤＭＡシステムにおける信号受信装置を提供することにある。
【０００９】
【課題を解決するための手段】
上記目的を達成するため、本発明のＤＳ−ＣＤＭＡシステムにおける信号受信装置は、受信信号を入力してＫ個（Ｋは２以上の整数）のパスに対するインパルスレスポンスを推定するインパルスレスポンス推定手段、前記インパルスレスポンス推定手段の出力から電力が最大となるパスを選択するパス選択手段、前記受信信号に対し、前記Ｋ個のパスにおける少なくとも自局のユーザチャンネルについて逆拡散を行う逆拡散手段、前記逆拡散手段の出力信号に対して同期検波を行うことにより、少なくとも前記自局のユーザチャンネルの初期データを出力する初期データ出力手段、前記初期データに基づいて、前記電力が最大となるパスを少なくとも除いたパスにおける、前記同期検波および前記逆拡散を行う以前の信号を生成することにより、前記電力が最大となるパスを少なくとも除いたパスにおける、少なくとも前記自局のユーザチャンネルの前記受信信号を仮想的に生成する干渉レプリカ生成手段、データ出力手段、および、最終データ出力手段を有するＤＳ−ＣＤＭＡシステムにおける信号受信装置であって、前記データ出力手段は、前記受信信号から前記干渉レプリカ生成手段の出力信号を差し引いた信号に対し、前記電力が最大となるパスにおける少なくとも前記自局のユーザチャンネルについて再び前記逆拡散を行った結果を逆拡散信号として出力し、前記最終データ出力手段は、前記逆拡散手段の出力信号と前記データ出力手段の逆拡散信号とを合成し少なくとも前記自局のユーザチャンネルの最終データを出力する。
【００１０】
そして、特に、前記受信信号は、複数のユーザチャンネルを備え、前記逆拡散手段は、前記受信信号に対し、前記Ｋ個のパスにおける前記複数のユーザチャンネルについて逆拡散し、前記初期データ出力手段は、前記複数のユーザチャンネルの初期データを出力し、前記干渉レプリカ生成手段は、前記電力が最大となるパスを少なくとも除いたパスにおける前記複数のユーザチャンネルの前記受信信号を仮想的に生成し、前記データ出力手段は、前記電力が最大となるパスにおける前記複数のユーザチャンネルについて再び前記逆拡散を行った結果を逆拡散信号として出力する。
【００１１】
また、本発明のＤＳ−ＣＤＭＡシステムにおける信号受信装置は、受信信号を入力してＫ個（Ｋは２以上の整数）のパスに対するインパルスレスポンスを推定するインパルスレスポンス推定手段、前記インパルスレスポンス推定手段の出力から電力が最大となるパスを選択するパス選択手段、前記受信信号に対し、前記Ｋ個のパスにおける少なくとも自局のユーザチャンネルについて逆拡散を行う逆拡散手段、前記逆拡散手段の出力信号に対して同期検波を行うことにより、少なくとも前記自局のユーザチャンネルの初期データを出力する初期データ出力手段、複数段の干渉レプリカ生成手段、複数段のデータ出力手段、および、最終データ出力手段を有するＤＳ−ＣＤＭＡシステムにおける信号受信装置であって、第１段目の前記干渉レプリカ生成手段は、前記初期データに基づいて、前記電力が最大となるパスを少なくとも除いたパスにおける、前記同期検波および前記逆拡散を行う以前の信号を生成することにより、前記電力が最大となるパスを少なくとも除いたパスにおける、少なくとも前記自局のユーザチャンネルの前記受信信号を仮想的に生成し、第２段目以降の前記干渉レプリカ生成手段は、当該段の前段の前記データ出力手段の出力データに基づいて、前記電力が最大となるパスを少なくとも除いたパスにおける、前記同期検波および前記逆拡散を行う以前の信号を生成することにより前記電力が最大となるパスを少なくとも除いたパスにおける、少なくとも前記自局のユーザチャンネルの前記受信信号を仮想的に生成し、最終段を除く前記データ出力手段は、前記受信信号から当該段の前記干渉レプリカ生成手段の出力信号を差し引いた信号に対し、前記電力が最大となるパスにおける少なくとも前記自局のユーザチャンネルについて再び逆拡散を行ってこの結果を逆拡散信号として出力するとともに、この逆拡散信号に対し、少なくとも前記自局のユーザチャンネルについて再び前記同期検波を行うことにより、少なくとも前記自局のユーザチャンネルのデータを出力し、最終段の前記データ出力手段は、前記受信信号から当該段の前記干渉レプリカ生成手段の出力信号を差し引いた信号に対し、前記電力が最大となるパスにおける少なくとも前記自局ユーザチャンネルについて再び逆拡散を行ってこの結果を逆拡散信号として出力し、前記最終データ出力手段は、前記逆拡散手段の出力信号と前記複数段のデータ出力手段の逆拡散信号とを合成し少なくとも前記自局のユーザチャンネルの最終データを出力する。
【００１２】
そして、特に、前記受信信号は、複数のユーザチャンネルを備え、前記逆拡散手段は、前記受信信号に対し、前記Ｋ個のパスにおける前記複数のユーザチャンネルについて逆拡散し、前記初期データ出力手段は、前記複数のユーザチャンネルの初期データを出力し、前記複数段の干渉レプリカ生成手段は、前記電力が最大となるパスを少なくとも除いたパスにおける前記複数のユーザチャンネルの前記受信信号を仮想的に生成し、最終段を除く前記データ出力手段は、前記電力が最大となるパスにおける前記複数のユーザチャンネルについて再び逆拡散を行ってこの結果を逆拡散信号として出力するとともに、この逆拡散信号に対し、前記複数のユーザチャンネルについて前記同期検波を行うことにより、前記複数のユーザチャンネルのデータを出力し、最終段の前記データ出力手段は、前記電力が最大となるパスにおける前記複数のユーザチャンネルについて再び逆拡散を行ってこの結果を逆拡散信号として出力する。
【００１３】
本発明のＤＳ−ＣＤＭＡシステムにおける信号受信装置では、前記インパルスレスポンス生成手段は、前記逆拡散手段が出力する、前記Ｋ個のパスにおける前記複数のユーザチャンネルについて逆拡散された信号の位相情報に基づいて、前記Ｋ個のパスにおけるインパルスレスポンスの位相を補正している。
【００１４】
また、本発明のＤＳ−ＣＤＭＡシステムにおける信号受信装置は、受信信号を入力して、Ｋ個（Ｋは２以上の整数）のパスに対し、少なくとも自局のユーザチャンネルについて逆拡散を行う逆拡散手段、この逆拡散手段の出力信号に対して同期検波を行うことにより、少なくとも前記自局のユーザチャンネルの初期データを出力する初期データ出力手段、干渉レプリカ生成手段、データ出力手段、および、最終データ出力手段を有するＤＳ−ＣＤＭＡシステムにおける信号受信装置であって、前記干渉レプリカ生成手段は、前記初期データに基づいて、前記Ｋ個のパスにおける、前記同期検波および前記逆拡散を行う以前の信号を生成することにより、前記Ｋ個のパスにおける、少なくとも前記自局のユーザチャンネルの前記受信信号を仮想的に生成し、前記データ出力手段は、前記受信信号から前記干渉レプリカ生成手段の出力信号を差し引いた信号に対し、前記Ｋ個のパスにおける少なくとも前記自局のユーザチャンネルについて再び前記逆拡散を行った結果を逆拡散信号として出力し、前記最終データ出力手段は、前記逆拡散手段の出力信号と前記データ出力手段の逆拡散信号とを合成し少なくとも前記自局のユーザチャンネルの最終データを出力する。
【００１５】
そして、特に、前記受信信号は、複数のユーザチャンネルを備え、前記逆拡散手段は、前記受信信号に対し、前記Ｋ個のパスにおける前記複数のユーザチャンネルについて逆拡散し、前記初期データ出力手段は、前記複数のユーザチャンネルの初期データを出力し、前記干渉レプリカ生成手段は、前記Ｋ個のパスにおける前記複数のユーザチャンネルの前記受信信号を仮想的に生成し、前記データ出力手段は、前記Ｋ個のパスにおける前記複数のユーザチャンネルについて再び前記逆拡散を行った結果を逆拡散信号として出力する。
【００１６】
また、本発明のＤＳ−ＣＤＭＡシステムにおける信号受信装置は、受信信号を入力して、Ｋ個（Ｋは２以上の整数）のパスに対し、少なくとも自局のユーザチャンネルについて逆拡散を行う逆拡散手段、この逆拡散手段の出力信号に対して同期検波を行うことにより、少なくとも前記自局のユーザチャンネルの初期データを出力する初期データ出力手段、複数段の干渉レプリカ生成手段、複数段のデータ出力手段、および、最終データ出力手段を有するＤＳ−ＣＤＭＡシステムにおける信号受信装置であって、第１段目の前記干渉レプリカ生成手段は、前記初期データに基づいて、前記Ｋ個のパスにおける、前記同期検波および前記逆拡散を行う以前の信号を生成することにより、前記Ｋ個のパスにおける、少なくとも前記自局ユーザチャンネルの前記受信信号を仮想的に生成し、第２段目以降の前記干渉レプリカ生成手段は、当該段の前段の前記データ出力手段の出力データに基づいて、前記Ｋ個のパスにおける、前記同期検波および前記逆拡散を行う以前の信号を生成することにより前記Ｋ個のパスにおける、少なくとも前記自局のユーザチャンネルの前記受信信号を仮想的に生成し、最終段を除く前記データ出力手段は、前記受信信号から当該段の前記干渉レプリカ生成手段の出力信号を差し引いた信号に対し、前記Ｋ個パスにおける少なくとも前記自局ユーザチャンネルについて再び逆拡散を行ってこの結果を逆拡散信号として出力するとともに、この逆拡散信号に対し、少なくとも前記自局のユーザチャンネルについて再び前記同期検波を行うことにより、少なくとも前記自局のユーザチャンネルのデータを出力し、最終段の前記データ出力手段は、前記受信信号から当該段の前記干渉レプリカ生成手段の出力信号を差し引いた信号に対し、前記Ｋ個のパスにおける少なくとも前記自局ユーザチャンネルについて再び逆拡散を行ってこの結果を逆拡散信号として出力し、前記最終データ出力手段は、前記逆拡散手段の出力信号と前記複数段のデータ出力手段の逆拡散信号とを合成し少なくとも前記自局のユーザチャンネルの最終データを出力する。
【００１７】
そして、特に、前記受信信号は、複数のユーザチャンネルを備え、前記逆拡散手段は、前記受信信号に対し、前記Ｋ個のパスにおける前記複数のユーザチャンネルについて逆拡散し、前記初期データ出力手段は、前記複数のユーザチャンネルの初期データを出力し、前記複数段の干渉レプリカ生成手段は、前記Ｋ個のパスにおける前記複数のユーザチャンネルの前記受信信号を仮想的に生成し、最終段を除く前記データ出力手段は、前記Ｋ個のパスにおける前記複数のユーザチャンネルについて再び逆拡散を行ってこの結果を逆拡散信号として出力するとともに、この逆拡散信号に対し、前記複数のユーザチャンネルについて前記同期検波を行うことにより、前記複数のユーザチャンネルのデータを出力し、最終段の前記データ出力手段は、前記Ｋ個のパスにおける前記複数のユーザチャンネルについて再び逆拡散を行ってこの結果を逆拡散信号として出力する。
【００１８】
本発明のＤＳ−ＣＤＭＡシステムにおける信号受信装置では、前記初期データ出力手段は、Ｒａｋｅ合成を行う。
【００１９】
さらに、本発明のＤＳ−ＣＤＭＡシステムにおける信号受信装置では、前記最終データ出力手段は、前記逆拡散手段の出力信号および前記複数段のデータ出力手段の逆拡散信号のうち最大値を示す信号のみに基づいて前記自局のユーザチャンネルの最終データを出力している。
【００２０】
また、前記最終データ出力手段は、前記逆拡散手段の出力信号および前記複数段のデータ出力手段の逆拡散信号の全ての信号を単純合成して、前記自局のユーザチャンネルの最終データを出力するようにしてもよい。
【００２１】
また、前記最終データ出力手段は、前記最終段のデータ出力手段の逆拡散信号のみに基づいて、前記自局のユーザチャンネルの最終データを出力することもできる。
【００２２】
また、前記最終データ出力手段は、前記逆拡散手段の出力信号および前記複数段のデータ出力手段の逆拡散信号の全ての信号のうち、最大のものから順に重みを付けて合成し、この合成値に基づいて前記自局のユーザチャンネルの最終データを出力することもできる。
【００２３】
また、前記最終データ出力手段は、前記逆拡散手段の出力信号および前記複数段のデータ出力手段の逆拡散信号の全ての信号のうち、最終段の前記データ出力手段の逆拡散信号から順に遡って重みを付けて合成し、この合成値に基づいて前記自局のユーザチャンネルの最終データを出力することもできる。
【００２４】
【発明の実施の形態】
以下、図示した一実施形態に基いて本発明を詳細に説明する。
【００２５】
[実施の形態１]
図１は、本発明の実施の形態１にかかるＤＳ−ＣＤＭＡシステムにおける信号受信装置の概略構成を示すブロック図である。この信号受信装置は、従来装置（第２９３０５８５号公報に記載の装置）の基本的な構成を維持しつつも、より受信性能を向上させることを目的とするものである。以下、従来装置を構成する各手段と同一のものには同一の符号を付して説明する。
【００２６】
本実施の形態の信号受信装置は、Ｒａｋｅ１０２にベースバンド受信信号が入力すると、Ｋ個（Ｋは２以上の整数）のパスに対するインパルスレスポンスを推定し、このインパルスレスポンスを表す基準信号を固定する。そして、この基準信号に基づいて、図示しない電力最大パス検出器が電力が最大となるパスＰを選択する。電力が最大となるパスＰは、干渉成分を含む割合が少なく、パスＰを除くパスについては主に干渉成分であると推定される。そこで、Ｒａｋｅ１０２では、このパスＰについて逆拡散を行い、この結果を逆拡散信号として最終データ出力手段１０６へ出力する。一方、前記逆拡散信号に対して同期検波を行い、この結果をデータＤＲ（１）として第１段目の干渉キャンセラ１０４−１へ出力する。
【００２７】
干渉キャンセラ１０４−１においては、Ｒａｋｅ部１０２から出力されたデータを初期データとして、電力が最大となるパスＰ以外のパスにおける、同期検波および逆拡散を行う以前の信号を生成するとともに、パイロットチャンネルの既知のデータに基づいて、電力が最大となるパスＰ以外のパスにおける、逆拡散を行う以前のパイロットチャンネルの信号を生成して干渉レプリカとし、受信信号からその干渉レプリカを差し引いて、電力が最大のパスＰについて再び逆拡散および同期検波を行う。そして、前記逆拡散によって得られた逆拡散信号は最終データ出力手段１０６へ、また、干渉成分がキャンセルされたより確からしいデータＤＣ（１）は第２段目の干渉キャンセラへ出力する。
【００２８】
第２段目以降の干渉キャンセラについては、前段の干渉キャンセラからの出力データが次の段の干渉キャンセラの入力データとなるとともに、パイロットチャンネルの既知のデータも入力される。何れの段の干渉キャンセラも、前記電力最大パス検出器から出力される同じパスＰを電力最大パスとして選択する。そして、第２段目以降の干渉キャンセラも第１段目の干渉キャンセラ１０４−１と同様に逆拡散信号は最終データ生成手段へ、また、干渉成分がキャンセルされたデータは次の段の干渉キャンセラへ出力する。ただし、最終段の干渉キャンセラ１０４−Ｍでは、干渉成分がキャンセルされたデータの出力は行わない。
【００２９】
最終データ出力手段１０６では、Ｒａｋｅ部１０２および第１段目の干渉キャンセラ１０４−１ないし第Ｍ段目の干渉キャンセラ１０４−ＭからパスＰに基づき逆拡散を行うことにより生成された逆拡散信号が集められ、それらの全ての信号を合成し（最大比合成）、最終データを出力する。
【００３０】
ここで、前述したように電力が最大となるパスＰが最も干渉成分を含む割合が少ないのと同様、電力が最大となる逆拡散信号が最も干渉成分を含む割合が小さいと考えられる。そこで、最大比合成を行う場合、電力が最大となる逆拡散信号に最大の重みを付け、電力が小さくなるに従ってその重みを小さくしていき、それらを全て合成する方式を採用することが好ましい。また、全ての逆拡散信号を単純に合成する方式でもよいし、電力が最大となる逆拡散信号のみに基づいて最終データを生成してもよい。
【００３１】
また、後段の干渉キャンセラほど干渉成分が除去された逆拡散信号を出力する可能性が高くなる理由から、最終段である第Ｍ段目の干渉キャンセラ１０４−Ｍの逆拡散信号に最大の重みを付け、その前段の干渉キャンセラへ行くほどその重みを小さくしていき、それらを全て合成することにより、最終データを生成してもよい。また、最終段である第Ｍ段目の干渉キャンセラ１０４−Ｍの逆拡散信号のみに基づいて最終データを生成することも可能である。
【００３２】
本実施の形態にかかるＤＳ−ＣＤＭＡシステムにおける信号受信装置は、以上のように構成されているので、マルチパスの相互相関による干渉を従来装置よりも高い割合で除去し、受信性能を格段に向上させることができる。
【００３３】
[実施の形態２]
図２は、本発明の実施の形態２にかかるＤＳ−ＣＤＭＡシステムにおける信号受信装置の概略構成を示す図である。本実施の形態の信号受信装置では、実施の形態１の装置とは異なり、Ｋ個（Ｋは２以上の整数）のパスのうち電力が最大となるパスＰのみを用いるのではなく、Ｋ個のパス全てを用いて最終データを生成する。したがって、実施の形態１の装置が有する、電力が最大となるパスＰを選択する電力最大パス検出器は不要となる。
【００３４】
本実施の形態の信号受信装置は、図示しないＲａｋｅ部、パス１の干渉キャンセラ２０２−１ないしパスＫの干渉キャンセラ２０２−Ｋからなる干渉キャンセラ２０２、および最終データ出力手段２０４により構成されており、実施の形態１に示したような各干渉キャンセラをカスケード接続する構成は採用していない。
【００３５】
本実施の形態にかかる信号受信装置では、Ｒａｋｅ部においてＫ個のパス全てについて逆拡散を行ってこの結果を逆拡散信号として最終データ出力手段２０４へ出力するとともに、前記逆拡散信号に対して同期検波を行ってこの結果をデータＤＲ（２）として干渉キャンセラ２０２へ出力する。干渉キャンセラ２０２では、データＤＲ（２）を各パスに対応したキャンセラ２０２−１ないし２０２−Ｋに振り分けて、各パスごとに対応した干渉キャンセラにおいてそれぞれ逆拡散を行ってこの結果を逆拡散信号として最終データ出力手段２０４へ出力する。最終データ出力手段２０４では、前記Ｒａｋｅ部からの逆拡散信号と干渉キャンセラ２０２−１ないし２００−Ｋからの逆拡散信号に基づき、実施の形態１において示した方法と同様の方法で最終データを生成する。
【００３６】
以上のように、本実施の形態では、Ｋ個のパスを全て用いて最終データを生成しているので、実施の形態１の装置よりもさらに受信性能を向上させることが可能になる。
【００３７】
[実施の形態３]
図３は、本発明の実施の形態３にかかるＤＳ−ＣＤＭＡシステムにおける信号受信装置に用いられる干渉キャンセラの内部構成を示す図である。本実施の形態の信号受信装置では、実施の形態１の装置とは異なり、Ｋ個（Ｋは２以上の整数）のパスのうち電力が最大となるパスＰのみを用いるのではなく、Ｋ個のパス全てを用いて最終データを生成する。したがって、実施の形態１の装置が有する、電力が最大となるパスＰを選択する電力最大パス検出器は不要となる。
【００３８】
本実施の形態にかかる信号受信装置では、Ｒａｋｅ部においてＫ個のパス全てについて逆拡散を行ってこの結果を逆拡散信号として最終データ出力手段へ出力するとともに、前記逆拡散信号に対して同期検波を行ってこの結果をデータＤＲ（３）として干渉キャンセラ３０２へ出力する。干渉キャンセラ３０２では、データＤＲ（３）を各パスに対応したキャンセラ３０２−１ないし３０２−Ｋに振り分けて、各パスごとに対応した干渉キャンセラにおいてそれぞれ逆拡散を行ってこの結果を逆拡散信号として最終データ出力手段へ出力する。同時に、前記各パスの逆拡散信号に対して同期検波を行い、この結果を後段の干渉キャンセラへ出力する。
【００３９】
以上のように、本実施の形態では、Ｋ個のパスを全て用いて最終データを生成しているので、実施の形態１の装置よりもさらに受信性能を向上させることが可能になる。
【００４０】
以上、本発明の一実施形態を図面に沿って説明した。しかしながら本発明は前記実施形態に示した事項に限定されず、特許請求の範囲の記載に基づいてその変更、改良等が可能であることは明らかである。例えば、前記各実施の形態では、干渉キャンセラがカスケード接続されているが、あまり高精度の受信性能が必要とされない場合には、Ｒａｋｅ部に対し１つの干渉キャンセラのみを接続した構成を採用することも可能である。
【００４１】
【発明の効果】
以上の如く本発明によれば、マルチパスの相互相関による干渉を高い割合で除去し、ＤＳ−ＣＤＭＡシステムにおける信号受信装置の受信性能を格段に向上させることができる。
【図面の簡単な説明】
【図１】実施の形態１にかかるＤＳ−ＣＤＭＡシステムにおける信号受信装置の概略構成を示すブロック図である。
【図２】実施の形態２にかかるＤＳ−ＣＤＭＡシステムにおける信号受信装置に用いられる干渉キャンセラの内部構成を示す図である。
【図３】実施の形態３にかかるＤＳ−ＣＤＭＡシステムにおける信号受信装置に用いられる干渉キャンセラの内部構成を示す図である。
【図４】従来のＤＳ−ＣＤＭＡシステムにおける信号受信装置の概略構成を示すブロック図である。
【符号の説明】
１０２Ｒａｋｅ部
１０４−１、１０４−Ｍ、２０２干渉キャンセラ
１０６最終データ出力手段
２０２−１パス１の干渉キャンセラ
２０２−ＫパスＫの干渉キャンセラ
２０４最終データ出力手段
３０２−１パス１の干渉キャンセラ
３０２−ＫパスＫの干渉キャンセラ[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a signal receiving apparatus in a DS-CDMA system, and in particular, to prevent reception performance deterioration due to multipath interference.
[0002]
[Prior art]
As a DS-CDMA (Direct Sequence-Code Division Multiple Access) system, there is a CDMA cellular telephone system (TIA IS95) standardized in North America. In this system, pilot symbols are inserted into a pilot channel and transmitted on the downlink (downlink), and the carrier phase is detected on the receiving side based on the received signal of this pilot channel to perform synchronous detection. However, this system has a drawback that when the transmission rate becomes high, the number of observed multipaths increases and the reception performance on the reception side deteriorates.
[0003]
As a solution to such a drawback, for example, there is a signal receiving apparatus including a multi-user / multi-stage type interference canceller described in Japanese Patent No. 2930585. FIG. 4 is a block diagram showing a schematic configuration of this signal receiving apparatus.
[0004]
In this signal receiving apparatus, first, the imp Le This response is estimated Le The basic signal representing the response is fixed and the rake unit 102 detects the output data DR. Further, a power maximum path detector (not shown) selects a path P having the maximum power based on the reference signal. The path P with the maximum power has a small ratio including the interference component, and the paths other than the path P are estimated to be mainly the interference component. Therefore, the interference canceller 104-1 uses the data output from the Rake unit 102 as initial data and generates a signal before performing synchronous detection and despreading in a path other than the path P with the maximum power, Based on the known data of the pilot channel, the signal of the pilot channel before despreading in the path other than the path P where the power is maximum is generated as an interference replica, and the interference replica is subtracted from the received signal. By performing despreading and synchronous detection again for the path P with the largest power, the data is verified again, and more probable data DC (1) with the interference component canceled is output.
[0005]
For the interference cancellers in the second and subsequent stages, output data from the interference canceller in the previous stage becomes input data for the interference canceller in the next stage, and known data of the pilot channel is also input. Any stage interference canceller selects the same path P output from the maximum power path detector as the maximum power path.
[0006]
The output data of an interference canceller at a certain stage is more accurate than the input data of this interference canceller. The interference canceller at the next stage inputs the output data of the interference canceller at the previous stage and generates a more probable interference replica. This more probable interference replica makes the output data of the interference canceller at that stage more probable. Therefore, the accuracy of the detection data can be improved by connecting the interference cancellers in M stages in cascade and setting the output data DC (M) of the M-th interference canceller 104-M as the final output.
[0007]
[Problems to be solved by the invention]
Thus, in the conventional signal receiving apparatus shown in FIG. 4, as the number of stages of interference cancellers increases, the accuracy of generating interference replicas can be improved, and the accuracy of detection data can be improved. However, on the other hand, the accuracy of output data from each interference canceller varies. In other words, since each interference canceller cannot remove the interference component at the same rate and output data, the accuracy of the data output from the final stage interference canceller is improved, but still includes some interference components. I can't deny it.
[0008]
Therefore, the present invention has been made in view of the above-described problems of the prior art, and its purpose is to eliminate interference caused by a multipath cross-correlation at a high rate and further improve the reception performance. -To provide a signal receiver in a CDMA system.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the signal receiving apparatus in the DS-CDMA system of the present invention, the received signal is input, the impulse response estimating means for estimating the impulse response for K paths (K is an integer of 2 or more), Path selection means for selecting the path with the maximum power from the output of the impulse response estimation means; despreading means for despreading the received signal for at least the user channel of the local station in the K paths; By performing synchronous detection on the output signal of the means, at least initial data output means for outputting initial data of the user channel of the own station, and based on the initial data, at least the path where the power is maximum is excluded By generating the signal before the synchronous detection and the despreading in the path DS having interference replica generation means, data output means, and final data output means for virtually generating at least the received signal of the user channel of the local station in a path excluding at least a path where the power is maximized A signal receiving apparatus in a CDMA system, wherein the data output means is a user of at least the own station in a path where the power is maximum with respect to a signal obtained by subtracting the output signal of the interference replica generation means from the received signal; The result of despreading again for the channel is output as a despread signal, and the final data output means combines the output signal of the despread means and the despread signal of the data output means to at least the own station Output the final data of the user channel.
[0010]
In particular, the received signal includes a plurality of user channels, and the despreading unit despreads the plurality of user channels in the K paths with respect to the received signal, and the initial data output unit includes Outputting the initial data of the plurality of user channels, the interference replica generation means virtually generates the received signals of the plurality of user channels in a path excluding at least a path having the maximum power, The data output means outputs, as a despread signal, a result of performing the despreading again on the plurality of user channels in the path with the maximum power.
[0011]
The signal receiving apparatus in the DS-CDMA system of the present invention includes: an impulse response estimating unit that inputs a received signal and estimates an impulse response with respect to K paths (K is an integer of 2 or more); Path selection means for selecting the path with the maximum power from the output; despreading means for performing despreading on at least the user channel of the local station in the K paths with respect to the received signal; output signal of the despreading means By carrying out synchronous detection, it has at least initial data output means for outputting initial data of the user channel of the own station, multiple stages of interference replica generation means, multiple stages of data output means, and final data output means A signal receiving apparatus in a DS-CDMA system, comprising: The power generation means generates the signal before performing the synchronous detection and the despreading in a path excluding at least a path where the power is maximum based on the initial data, thereby maximizing the power. Virtually generating at least the received signal of the user channel of the own station in a path excluding at least the path, and the interference replica generating means in the second stage and thereafter are outputs of the data output means in the preceding stage of the stage Based on the data, in the path excluding at least the path where the power is maximized by generating the signal before performing the synchronous detection and the despreading in the path except at least the path where the power is maximized. At least the received signal of the user channel of the local station is virtually generated, and the data output means excluding the final stage is configured to The signal obtained by subtracting the output signal of the interference replica generation means at the stage from the received signal is despread again for at least the user channel of the local station in the path where the power is maximum, and the result is used as a despread signal. And at the same time outputting at least the data of the user channel of the local station by performing the synchronous detection again for at least the user channel of the local station with respect to the despread signal, The signal obtained by subtracting the output signal of the interference replica generation means at the stage from the received signal is despread again for at least the local user channel in the path where the power is maximum, and the result is used as a despread signal. The final data output means outputs the output signal of the despreading means and the composite signal. The despread signals from several stages of data output means are combined to output at least the final data of the user channel of the own station.
[0012]
In particular, the received signal includes a plurality of user channels, and the despreading unit despreads the plurality of user channels in the K paths with respect to the received signal, and the initial data output unit includes The initial data of the plurality of user channels is output, and the plurality of stages of interference replica generation means virtually generate the reception signals of the plurality of user channels in a path excluding at least a path having the maximum power. The data output means excluding the final stage performs despreading again for the plurality of user channels in the path where the power is maximum and outputs the result as a despread signal. By performing the synchronous detection on the plurality of user channels, data of the plurality of user channels is obtained. Outputs, said data output means of the last stage, the power is by performing inverse spread again for the plurality of user channels in a path having a maximum and outputs the result as despread signal.
[0013]
In the signal receiving apparatus in the DS-CDMA system of the present invention, the impulse response generating means is based on phase information of signals despread for the plurality of user channels in the K paths output from the despreading means. Thus, the phase of the impulse response in the K paths is corrected.
[0014]
Further, the signal receiving apparatus in the DS-CDMA system of the present invention receives a received signal and performs despreading for at least the user channel of the own station with respect to K paths (K is an integer of 2 or more). Means, by performing synchronous detection on the output signal of the despreading means, at least initial data output means for outputting initial data of the user channel of the own station, interference replica generation means, data output means, and final data A signal receiving apparatus in a DS-CDMA system having an output unit, wherein the interference replica generation unit is configured to output a signal before performing the synchronous detection and the despreading in the K paths based on the initial data. By generating, the received signal of at least the user channel of the own station in the K paths is virtually The data output means performs the despreading again on at least the user channel of the local station in the K paths with respect to the signal obtained by subtracting the output signal of the interference replica generation means from the received signal. The result is output as a despread signal, and the final data output means combines the output signal of the despread means and the despread signal of the data output means and outputs at least the final data of the user channel of the own station.
[0015]
In particular, the received signal includes a plurality of user channels, and the despreading unit despreads the plurality of user channels in the K paths with respect to the received signal, and the initial data output unit includes , Outputting initial data of the plurality of user channels, the interference replica generation means virtually generating the received signals of the plurality of user channels in the K paths, and the data output means A result obtained by performing the despreading again on the plurality of user channels in the number of paths is output as a despread signal.
[0016]
Further, the signal receiving apparatus in the DS-CDMA system of the present invention receives a received signal and performs despreading for at least the user channel of the own station with respect to K paths (K is an integer of 2 or more). Means, by performing synchronous detection on the output signal of the despreading means, at least initial data output means for outputting initial data of the user channel of the own station, a plurality of stages of interference replica generation means, a plurality of stages of data output And a signal reception apparatus in a DS-CDMA system having final data output means, wherein the interference replica generation means in the first stage is configured to synchronize the synchronization in the K paths based on the initial data. By generating a signal before performing detection and despreading, at least the local station user channel in the K paths The interference replica generation means in the second and subsequent stages is generated based on the output data of the data output means in the preceding stage of the stage, and the synchronization replicas in the K paths are virtually generated. By virtually generating the received signal of the user channel of the local station in the K paths by generating a signal before performing detection and despreading, the data output means excluding the final stage is: The signal obtained by subtracting the output signal of the interference replica generation means at the corresponding stage from the received signal is despread again for at least the local user channel in the K paths, and the result is output as a despread signal. By performing the synchronous detection again on at least the user channel of the local station for the despread signal, The user channel data of the own station is output, and the data output means at the final stage is at least the signals in the K paths with respect to a signal obtained by subtracting the output signal of the interference replica generation means at the stage from the received signal. The local user channel is despread again and the result is output as a despread signal. The final data output means combines the output signal of the despread means and the despread signals of the multi-stage data output means. At least the final data of the user channel of the own station is output.
[0017]
In particular, the received signal includes a plurality of user channels, and the despreading unit despreads the plurality of user channels in the K paths with respect to the received signal, and the initial data output unit includes Output the initial data of the plurality of user channels, and the plurality of stages of interference replica generation means virtually generate the received signals of the plurality of user channels in the K paths, and exclude the final stage. The data output means performs despreading again for the plurality of user channels in the K paths and outputs the result as a despread signal, and the synchronous detection for the plurality of user channels with respect to the despread signal. To output data of the plurality of user channels, and the data output means in the final stage Serial performing despreading again for the plurality of user channels in the K path and outputs the result as despread signal.
[0018]
In the signal receiving apparatus in the DS-CDMA system of the present invention, the initial data output means performs Rake combining.
[0019]
Further, in the signal receiving apparatus in the DS-CDMA system of the present invention, the final data output means is only a signal indicating the maximum value among the output signal of the despreading means and the despread signals of the data output means of the plurality of stages. Based on this, the final data of the user channel of the own station is output.
[0020]
The final data output means simply synthesizes all signals of the output signal of the despreading means and the despread signals of the plurality of stages of data output means, and outputs the final data of the user channel of the local station. You may do it.
[0021]
Further, the final data output means can output the final data of the user channel of the own station based only on the despread signal of the data output means at the final stage.
[0022]
Further, the final data output means synthesizes weighted values in order from the largest one of the output signals of the despreading means and the despread signals of the plurality of stages of data output means. The final data of the user channel of the own station can be output based on the above.
[0023]
The final data output means traces back in order from the despread signal of the data output means in the final stage, out of all signals of the output signal of the despread means and the despread signals of the data output means of the plurality of stages. It is also possible to combine with weighting and output the final data of the user channel of the own station based on the combined value.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail based on the illustrated embodiment.
[0025]
[Embodiment 1]
FIG. 1 is a block diagram showing a schematic configuration of a signal receiving apparatus in the DS-CDMA system according to the first embodiment of the present invention. This signal receiving device is intended to further improve the receiving performance while maintaining the basic configuration of the conventional device (the device described in Japanese Patent No. 2930585). In the following description, the same reference numerals are given to the same components as those constituting the conventional apparatus.
[0026]
When a baseband received signal is input to Rake 102, the signal receiving apparatus according to the present exemplary embodiment performs impulsivity for K paths (K is an integer of 2 or more). Le This response is estimated Le The reference signal representing the response is fixed. Based on this reference signal, a power maximum path detector (not shown) selects a path P that maximizes the power. The path P with the maximum power has a small ratio including the interference component, and the paths other than the path P are estimated to be mainly the interference component. Therefore, the Rake 102 performs despreading on the path P and outputs the result to the final data output means 106 as a despread signal. On the other hand, synchronous detection is performed on the despread signal, and the result is output as data DR (1) to the first-stage interference canceller 104-1.
[0027]
Interference canceller 104-1 uses the data output from Rake unit 102 as initial data, generates a signal before performing synchronous detection and despreading in a path other than path P where the power is maximum, and pilot channel. Based on the known data, a signal of a pilot channel before despreading is generated in a path other than the path P having the maximum power as an interference replica, and the interference replica is subtracted from the received signal. Despreading and synchronous detection are performed again for the maximum path P. Then, the despread signal obtained by the despreading is output to the final data output means 106, and the more probable data DC (1) from which the interference component has been canceled is output to the second stage interference canceller.
[0028]
For the interference cancellers in the second and subsequent stages, output data from the interference canceller in the previous stage becomes input data for the interference canceller in the next stage, and known data of the pilot channel is also input. Any stage interference canceller selects the same path P output from the maximum power path detector as the maximum power path. Similarly to the first stage interference canceller 104-1, the second stage and subsequent stage interference cancellers send the despread signal to the final data generating means, and the data whose interference components have been canceled are the next stage interference cancellers. Output to. However, the interference canceller 104-M at the final stage does not output data with the interference component canceled.
[0029]
In the final data output means 106, the despread signal generated by despreading from the Rake unit 102 and the first-stage interference canceller 104-1 to the M-th interference canceller 104-M based on the path P is received. Collected, synthesizes all these signals (maximum ratio synthesis) and outputs final data.
[0030]
Here, as described above, it is considered that the ratio of the despread signal with the maximum power containing the smallest interference component is the same as the path P with the largest power containing the smallest interference component. Therefore, when maximum ratio combining is performed, it is preferable to employ a method in which a maximum weight is assigned to a despread signal that maximizes power, the weight is decreased as power decreases, and all of them are combined. Further, a method of simply combining all the despread signals may be used, or the final data may be generated based only on the despread signal having the maximum power.
[0031]
Further, because the possibility of outputting a despread signal from which interference components have been removed increases as the latter stage interference canceller increases, the maximum weight is assigned to the despread signal of the M-th stage interference canceller 104-M as the final stage. In addition, the final data may be generated by reducing the weight as the interference canceller in the preceding stage is reduced and combining them all. It is also possible to generate final data based only on the despread signal of the M-th stage interference canceller 104-M, which is the final stage.
[0032]
Since the signal receiving apparatus in the DS-CDMA system according to the present embodiment is configured as described above, the interference due to multipath cross-correlation is removed at a higher rate than the conventional apparatus, and the receiving performance is greatly improved. Can be made.
[0033]
[Embodiment 2]
FIG. 2 is a diagram showing a schematic configuration of a signal receiving apparatus in the DS-CDMA system according to the second embodiment of the present invention. Unlike the apparatus according to the first embodiment, the signal receiving apparatus according to the present embodiment does not use only the path P having the maximum power among the K paths (K is an integer of 2 or more), but K paths. The final data is generated using all the paths. Therefore, the power maximum path detector that selects the path P having the maximum power, which the apparatus according to the first embodiment has, becomes unnecessary.
[0034]
The signal receiving apparatus according to the present embodiment includes a Rake unit (not shown), an interference canceller 202 including a path 1 interference canceller 202-1 to a path K interference canceller 202-K, and a final data output unit 204. A configuration in which the interference cancellers are cascade-connected as shown in the first embodiment is not employed.
[0035]
In the signal receiving apparatus according to the present embodiment, the Rake unit performs despreading for all K paths and outputs the result to the final data output means 204 as a despread signal, and is synchronized with the despread signal. Detection is performed, and the result is output to the interference canceller 202 as data DR (2). The interference canceller 202 distributes the data DR (2) to the cancellers 202-1 to 202-K corresponding to each path, performs despreading in the interference canceller corresponding to each path, and uses the result as a despread signal. Output to the final data output means 204. The final data output unit 204 generates final data based on the despread signal from the Rake unit and the despread signal from the interference cancellers 202-1 to 200-K by the same method as described in the first embodiment. To do.
[0036]
As described above, in the present embodiment, since the final data is generated using all K paths, it is possible to further improve the reception performance as compared with the apparatus of the first embodiment.
[0037]
[Embodiment 3]
FIG. 3 is a diagram showing an internal configuration of an interference canceller used in the signal receiving apparatus in the DS-CDMA system according to the third embodiment of the present invention. Unlike the apparatus according to the first embodiment, the signal receiving apparatus according to the present embodiment does not use only the path P having the maximum power among K paths (K is an integer of 2 or more), but K paths. The final data is generated using all the paths. Therefore, the power maximum path detector that selects the path P having the maximum power, which the apparatus according to the first embodiment has, becomes unnecessary.
[0038]
In the signal receiving apparatus according to the present embodiment, the Rake unit performs despreading for all K paths and outputs the result to the final data output means as a despread signal, and performs synchronous detection on the despread signal. And outputs this result to the interference canceller 302 as data DR (3). In the interference canceller 302, the data DR (3) is distributed to the cancellers 302-1 to 302-K corresponding to each path, and each interference canceller corresponding to each path performs despreading, and the result is used as a despread signal. Output to final data output means. At the same time, synchronous detection is performed on the despread signal of each path, and the result is output to the subsequent interference canceller.
[0039]
As described above, in this embodiment, since the final data is generated using all K paths, it is possible to further improve the reception performance as compared with the apparatus of the first embodiment.
[0040]
The embodiment of the present invention has been described with reference to the drawings. However, the present invention is not limited to the matters shown in the above-described embodiments, and it is obvious that changes, improvements, and the like can be made based on the description of the scope of claims. For example, in each of the above-described embodiments, interference cancellers are cascade-connected, but when a highly accurate reception performance is not required, a configuration in which only one interference canceller is connected to the Rake unit is adopted. Is also possible.
[0041]
【The invention's effect】
As described above, according to the present invention, interference due to multipath cross-correlation can be removed at a high rate, and the reception performance of the signal receiving apparatus in the DS-CDMA system can be significantly improved.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a schematic configuration of a signal receiving apparatus in a DS-CDMA system according to a first embodiment;
FIG. 2 is a diagram illustrating an internal configuration of an interference canceller used in a signal receiving apparatus in the DS-CDMA system according to the second embodiment.
FIG. 3 is a diagram illustrating an internal configuration of an interference canceller used in a signal receiving apparatus in a DS-CDMA system according to a third embodiment;
FIG. 4 is a block diagram showing a schematic configuration of a signal receiving apparatus in a conventional DS-CDMA system.
[Explanation of symbols]
102 Rake part
104-1, 104-M, 202 Interference canceller
106 Final data output means
202-1 Interference canceller for path 1
202-K Path K interference canceller
204 Final data output means
302-1 Path 1 interference canceller
302-K Path K interference canceller

Claims

Impulse response estimation means for inputting an received signal and estimating an impulse response to K paths (K is an integer of 2 or more);
Path selection means for selecting the path with the maximum power from the output of the impulse response estimation means;
With respect to the received signal, despreading means for power that put on the K paths to perform despreading for the path with the maximum,
By performing synchronous detection on the output signal of the despreading means, the initial data output means for outputting the initial data,
Interference canceller means, and
A final data output means,
The interference canceller unit, based on the initial data, together with the power to generate a previous signal for despreading that put a path other than the path having the maximum on the basis of the known data of the pilot channel, power and generates a signal of a previous pilot channel despreading at a path other than the path having the maximum generates an interference replica to the signal obtained by subtracting the interference replica from the received signal, the path in which the power is maximum the result of again despreads have that described the output as despread signal,
The signal reception apparatus in a DS-CDMA system, wherein the final data output means outputs final data based on despread signals output from the despreading means and the interference canceller means .

Impulse response estimation means for inputting an received signal and estimating an impulse response to K paths (K is an integer of 2 or more);
Path selection means for selecting the path with the maximum power from the output of the impulse response estimation means;
With respect to the received signal, despreading means for power that put on the K paths to perform despreading for the path with the maximum,
By performing synchronous detection on the output signal of the despreading means, the initial data output means for outputting the initial data,
Multi-stage interference canceller means, and
Final data output means includes a,
The interference canceller unit of the first stage, based on the initial data, together with the power to generate a previous signal for despreading that put a path other than the path having the maximum in the known data of the pilot channel Based on the above, a pilot channel signal before despreading in a path other than the path where power is maximum is generated to generate an interference replica ,
The interference canceller unit of the second stage and thereafter the generated previous signal based on the output data of the interference canceller unit of the preceding stage of the stages, the power despreading that put a path other than the path having the maximum In addition, based on the known data of the pilot channel, an interference replica is generated by generating a signal of the pilot channel before despreading in a path other than the path where the power is maximum ,
The interference canceller unit, with respect to the interference replica signal obtained by subtracting of the stage from the received signal, despread signals the result of performing the despreading again have pass Nitsu the power becomes maximum with the exception of the last stage and outputting the results as relative to the despread signal, by performing again synchronous detection, and outputs the data,
The interference canceller unit of the final stage, to the signal obtained by subtracting the interference replica of the stage from the received signal, a result the power is subjected to despreading again have pass Nitsu maximized as despread signal Output,
The signal reception apparatus in a DS-CDMA system, wherein the final data output means outputs final data based on the despread signals output from the despreading means and the multistage interference canceller means .

Despreading means for inputting a received signal and performing despreading for all K paths (K is an integer of 2 or more);
By performing synchronous detection on the output signal of the despreading means, the initial data output means for outputting the initial data,
Interference canceller means, and
Final data output means includes a,
The interference canceller means outputs a result of despreading again for the K paths based on the initial data as a despread signal,
The signal reception apparatus in a DS-CDMA system, wherein the final data output means outputs final data based on despread signals output from the despreading means and the interference canceller means .

Despreading means for inputting a received signal and performing despreading for all K paths (K is an integer of 2 or more);
By performing synchronous detection on the output signal of the despreading means, the initial data output means for outputting the initial data,
Multi-stage interference canceller means, and
Final data output means includes a,
The interference canceller means in the first stage outputs the result of despreading again for the K paths based on the initial data as a despread signal, and again performs synchronous detection on the despread signal. To output the data,
The interference canceller means in the second and subsequent stages excluding the final stage uses the result of despreading again for the K paths based on the output data of the interference canceller means in the previous stage of the stage as a despread signal. In addition to outputting, by performing synchronous detection again on this despread signal, data is output,
The interference canceller means at the final stage outputs, as a despread signal, the result of despreading again for the K paths based on the output data of the interference canceller means at the previous stage of the stage ,
The signal reception apparatus in a DS-CDMA system, wherein the final data output means outputs final data based on the despread signals output from the despreading means and the multistage interference canceller means .

4. The DS according to claim 1, wherein the final data output unit simply combines the signals of the despread signals output from the despreading unit and the interference canceller unit, and outputs final data. 5. A signal receiving device in a CDMA system;

The final data output means, by simply combining all signals despread signal output from the interference canceller unit of the plurality of stages and the despreading means, claim and outputs a final data 2 or 5. A signal receiving apparatus in the DS-CDMA system according to 4 .

The final data output means outputs final data based only on a signal indicating a maximum value among the despread signals output from the despread means and the interference canceller means in a plurality of stages. 5. A signal receiving apparatus in the DSCDMA system according to 2 or 4.

The final data output means, based on only the despread signal output from the interference canceller unit of the last stage, the signal reception in DSCDMA system according to claim 2 or 4, and outputs a final data apparatus.

The final data output means combines the despread signals and the despread signals output from the despread means and the multiple stages of interference canceller means with weights in order from the largest one, and based on the combined value Te, the signal receiving apparatus in DS-CDMA system according to claim 2 or 4, wherein outputting the final data.

The final data output means traces back in order from the despread signal output from the last stage interference canceller means among all the despread signals output from the despread means and the plurality of stages of interference canceller means. synthesized and weighted Te, based on the combined value, signal receiving apparatus in DS-CDMA system according to claim 2 or 4, wherein outputting the final data.