Equalizer device, receiver device and equalization method

An equalizer device comprising:

• a CIR generating unit for generating an channel impulse response from a received signal;
• a CIR variation detection unit for using a plurality of channel impulse responses generated from a plurality of different sections of the received signal by the CIR generating unit to detect an amount of variation in the channel impulse response;
• an equivalent width control unit for determining an equivalent width corresponding to a signal length used in equalization of the received signal such that the equivalent width is shortened as the amount of variation in the channel impulse response increases;
• and
• a waveform equalization unit for using the channel impulse response generated by the CIR generating unit to equalize the received signal over the equivalent width determined by the equivalent width control unit and generate a demodulated signal.

An equalization method comprising:

• a CIR generating step for generating an channel impulse response from a received signal;
• a CIR variation detection step for using a plurality of channel impulse responses generated from a plurality of different sections of the received signal in the CIR generating step to detect an amount of variation in the channel impulse response;
• an equivalent width control step for determining an equivalent width corresponding to a signal length used in equalization of the received signal such that the equivalent width is shortened as the amount of variation in the channel impulse response increases;
• and
• a waveform equalization step for using the channel impulse response generated in the CIR generating step to equalize the received signal over the equivalent width determined in the equivalent width control step and generate a demodulated signal.