摘要 |
This invention is to provide a receiver and a reception method capable of improving a reception quality with respect to both FM modulation wave and AM modulation wave, and ensuring an effective receiver even under a flat fading or a frequency selective fading. The receiver comprises: an adaptation synthesizing section ADF which receives modulation signals IFA and IFB outputted from receiving sections RXa and RXb, and performs an adaptation processing in an adaptation filter to generate a modulation signal Y(t) as a prediction signal; feature extraction units 30, 40 for feature-extracting envelopes of modulation signals IFA, IFB and outputting feature extraction signals Eva, EVb; an adder unit 50 for adding together the feature extraction signals Eva, EVb and generating an addition feature extraction signal Esum; and a tap coefficient altering unit 60 for adjusting tap coefficient of the adaptation filter of the adaptation synthesizing section so as to approximate the modulation signal Y(t) to the addition feature extraction signal Esum. When the modulation signals IFA, IFB are AM-modulated signals, a pass frequency band of the feature extraction units 30, 40 is switched over to a cut-off frequency f 1 which is higher than a frequency band of an AM-demodulated signal Sd. When the modulation signals are FM-modulated signals, a pass frequency band of the feature extraction units 30, 40 is switched over to a cut-off frequency f 2 which is lower than an AM altering frequency generated due to a frequency selective fading of the modulation signals IFA, IFB.
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