Decision-feedback equalizer capable of producing an equalized signal at high speed

A decision-feedback equalizer connected to a demodulator section for demodulating a received signal into a demodulated signal, said decision-feedback equalizer comprising:

• first filter means for filtering said demodulated signal into a first filtered signal in accordance with a plurality of main controllable tap gains, said first filter means producing a first local signal from said demodulated signal;
• second filter means for filtering an input signal into a second filtered signal in accordance with a plurality of subsidiary controllable tap gains;
• producing means for producing an equalized signal in response to said first and said second filtered signals;
• control means for controlling said main controllable tap gains and said subsidiary controllable tap gains in accordance with said demodulated signal and said equalized signal;
• detecting means for detecting whether or not said demodulator section is put in a synchronization state and producing a synchronization signal when said demodulator section is put in said synchronization state, said detecting means otherwise producing a nonsynchronization signal;
• and
• supplying means responsive to said synchronization signal for supplying said second filter means with said first local signal as said input signal, and said supplying means supplying said second filter means with a second local signal as said input signal on the basis of said equalized signal in response to said nonsynchronization signal.