Amplitude compensation circuit



【課題】データの伝送レートを高めながら、フェージングなどによる振幅の変動を効果的に補償できるようにする。 【解決手段】直交検波部3で検波された多値変調のI相(同相)成分とQ相(直交)成分とからなるI,Q信号は、乗算部7でゲインGが乗算され、次に、等化器5に供給されて波形等化される。等化器5では、シンボル毎にタップ係数Wfが生成され、これで波形等化が行なわれるが、このタップ係数Wfは、また、ベクトル長出力部8に供給されてタップ係数Wfのベクトル長Rが算出され、平均化部9でシンボル毎に順次得られたベクトル長Rを平均化することにより、上記のゲインGが得られる。このようにして得られるゲインGは、ベクトル長Rが一定の値となるような、即ち、I,Q信号が所定の振幅となって振幅変動がなくなるような値に収束する。 【選択図】図1
<P>PROBLEM TO BE SOLVED: To effectively compensate variation of amplitude by phasing, etc. while enhancing transfer rate of data. <P>SOLUTION: Gains G of I and Q signals consisting of I phase (inphase) components and Q phase (quadrature phase) components of multilevel modulation, detected by a quadrature detection part 3 are multiplied by a multiplication part 7, next, the I and Q signals are supplied to an equalizer 5 and waveform equalization is performed. In the equalizer 5, tap coefficients Wfs are generated by every symbol and the waveform equalization is performed by them, in addition, the tap coefficients Wf are supplied to a vector length output part 8, pieces of vector length R of the tap coefficients R are calculated and the gains G are obtained by averaging pieces of the vector length R sequentially obtained by every symbol by an averaging part 9. The gains G which are obtained in such a way are converged to values so that the pieces of vector length R become fixed values, namely, the I and Q signals become predetermined amplitude and amplitude variation is lost. <P>COPYRIGHT: (C)2005,JPO&NCIPI




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    JP-2007013505-AJanuary 18, 2007Kenwood Corp, 株式会社ケンウッドSymbol discrimination apparatus for modulation signal, symbol discrimination method of modulation signal, symbol discrimination program for modulation signal, and recording medium
    JP-4508960-B2July 21, 2010株式会社ケンウッド変調信号のシンボル判定装置、変調信号のシンボル判定方法、変調信号のシンボル判定プログラム及び記録媒体