Equalizer for use in multi-carrier modulation systems

An equalization method for equalizing received signals transmitted over a communications channel for the duration of a transmission using equalization coefficients, comprising the steps of:

• estimating a channel impulse response of the communications channel using a known signal transmitted in an initial portion of the transmission;
• determining a sampling time difference offset values n 0 ′
• between the estimated channel impulse response and an equalized channel impulse response;
• determining a cost function J according to the following:
• J ⁢ ( n 0 ′ ) = { ( TEQ n ⊗ h n ) - γ ⁢ ⁢ δ ⁢ ( n - n 0 ′ ) } 2
• where TEQn corresponds to the equalization coefficients, hn depicts the channel impulse response, corresponds to convolution, γ is a scaling factor, and δ(n) corresponds to a unit pulse;
• and
• determining the equalization coefficients for a sampling time difference corresponding to a minimum of the determined cost function J.

An equalization method for equalizing received signals transmitted over a communications channel for the duration of a transmission using equalization parameters, comprising the steps of:

• estimating a channel impulse response of the communications channel using a known signal transmitted in the initial portion of the transmission;
• determining an offset value between the estimated channel impulse response and an equalized channel impulse response;
• determining the equalization parameters using the determined offset value;
• manipulating the channel impulse response to determine a corresponding autocorrelation function;
• assembling the autocorrelation function as a krakovian;
• inverting the krakovian;
• and
• determining values for the channel model parameters using the inverted krakovian.

In a receiver that receives signals transmitted over a communications channel where the received signals are compensated in an equalizer for effects of the communications channel on the transmitted signal, a method, comprising the steps of:

• estimating a channel impulse response for the communications channel;
• estimating an autocorrelation function associated with the channel impulse response;
• calculating coefficients for the equalizer from the estimated channel impulse response and the estimated autocorrelation function;
• determining a mean square error associated with imperfect equalization;
• determining a cost function associated with the mean square error and a sampling time offset;
• and
• calculating the equalizer coefficients using the determined cost function.