Fast start-up system for automatic transversal equalizers

Claim 2

In combination with a receiver for a synchronous data transmission system in which attenuators connected to taps on an associated transversal equalizer are adjusted by correlating actual received signals with a desired reference signal, meAns for establishing initial tap attenuator settings rapidly comprising a matrix of resistors connected between each of said taps and each of said attenuators, the values of said resistors being determined in accordance with the amplitude characteristics of a distorting transmission medium to render the input signals effective at said attenuators mutually orthogonal.

Claim 3

An automatic transversal equalizer for synchronous digital signals comprising a delay line having a plurality of taps consecutively spaced by the synchronous signaling interval, a variable attenuator associated with each of said taps, a combining circuit, means for connecting all said attenuators to said combining circuit, means responsive to the difference between the output of said combining circuit when a distorted impulse response signal is applied to said equalizer and a reference impulse response for forming an error signal, means responsive to a correlation of signal components at each of said taps with said error signal for varying said attenuators in a direction to minimize said error signal, and means for orthogonalizing the several signals appearing at said taps to minimize the number of adjustments required to bring said attenuators to optimum settings, said orthogonalizing means comprising a matrix of fixed resistors interconnecting each of said taps with each of said attenuators, the values of said resistors being selected such that a matrix A whose elements are summations of the cross-products of signals sampled at said taps when multiplied by a matrix P whose elements are the division ratio values of said fixed resistors results in the identity matrix whose principal diagonal elements are unity and all other elements are zero.

Claim 4

An automatic transversal equalizer for synchronous digital signals comprising a delay line having a plurality of taps consecutively spaced by the synchronous signaling interval, a variable attenuator associated with each of said taps, a combining circuit, means for connecting all said attenuators to said combining circuit, means responsive to the difference between the output of said combining circuit when a distorted impulse response signal is applied to said equalizer and a reference impulse response for forming an error signal, means responsive to a correlation of signal components at each of said taps with said error signal for varying said attenuators in a direction to minimize said error signal, and means for orthogonalizing the several signals appearing at said taps to minimize the number of adjustments required to bring said attenuators to optimum settings, said orthogonalizing means comprising a matrix of fixed resistors interconnecting each of said taps with each of said attenuators, the values of said resistors being selected such that a matrix A whose elements are summations of the cross-products of signals sampled at said taps when multiplied by a matrix P whose elements are the division ratio values of said fixed resistors results in the identity matrix whose principal diagonal elements are unity and all other elements are zero.

Claim 5

In an automatic transversal equalizer for a synchronous partial-response data transmission system in which there is a high degree of correlation between successive signals, a tapped delay line with a tap spacing equal to the reciprocal of the synchronous band rate a variable attenuator associated with each of said taps, means for adjusting said attenuators in accordance with the mean-square error difference between the summation of delay components of an impulse signal applied to said equalizer after weighting by said attenuators and a reference impulse signal, and means for minimizing the number of adjustments for equalizer convergence comprising an array of resistors interconnecting each of said taps with each of said variable attenuators, the values of said resistors being such that signals incident at said variable attenuators are mutually orthogonal.

Claim 6

In an automatic transversal equalizer for a synchronous partial-response data transmission system in which there is a high degree of correlation between successive signals, a tapped delay line with a tap spacing equal to the reciprocal of the synchronous band rate a variable attenuator associated with each of said taps, means for adjusting said attenuators in accordance with the mean-square error difference between the summation of delay components of an impulse signal applied to said equalizer after weighting by said attenuators and a reference impulse signal, and means for minimizing the number of adjustments for equalizer convergence comprising an array of resistors interconnecting each of said taps with each of said variable attenuators, the values of said resistors being such that signals incident at said variable attenuators are mutually orthogonal.