Initialization of adaptive control systems

Claim 2

In an adaptive transversal equalizer control system including a plurality of selectively adjustable attenuators operating on a common input signal; combining means for weighted signals from all said attenuators; and means for generating an error signal for control of said attenuators from the difference between direct and normalized outputs of said combining means: means for presetting said attenuators to a predetermined set of values comprising a direct connection established during each presetting operation for said common input signal to said error generating means in place of the normalized output of said combining means and means for applying an arbitrary test signal to the input of said system.

Claim 3

Presetting means as defined in claim 1 in which said predetermined set of values comprises a unity coefficient for one of said attenuators selected as a reference attenuator and zero coefficients for all other attenuators.

Claim 4

The adaptive control system of claim 1 in which an auxiliary fixed weighting element is provided for each attenuator requiring a nonzero value and said fixed weighting elements are joined at one end to said direct connection at said error generating means during presetting.

Claim 5

Presetting means as defined in claim 1 in combination with switching means providing connection in the alternative to said error-generating means from the normalized output of said combining means or from the input of a particular one of said attenuators selected as a reference attenuator.

Claim 6

The adaptive control system defined in claim 1 in which the several attenuators differ from each other by their frequency-domain signal shaping characteristics.

Claim 7

The adaptive control system defined in claim 1 in which the several attenuators are separated from each other by a plurality of time delay units.

Claim 8

In combination with an adaptive transversal equalizer having a plurality of signal taps separated from each other by discrete time-delay units, one of said taps being designated a reference tap; an adjustable attenuator at each of said taps; means for combining the weighted signals from said attenuators to form respective analog and quantized outputs; an error difference circuit normally having an inputs the respective outputs of said combining means and producing an output from which control signals for said attenuators are derived: the improvement providing rapid presetting of said attenuators to a reference state comprising a direct electrical connection established during presetting between said reference tap and the input of said error difference circuit to which the quantized output of said combining means is normally connected and in substitution therefor.

Claim 9

In combination with an adaptive transversal equalizer having a plurality of signal taps separated from each other by discrete time-delay units, one of said taps being designated a reference tap; an adjustable attenuator at each of said taps; means for combining the weighted signals from said attenuators to form respective analog and quantized outputs; an error difference circuit normally having an inputs the respective outputs of said combining means and producing an output from which control signals for said attenuators are derived: the improvement providing rapid presetting of said attenuators to a reference state comprising a direct electrical connection established during presetting between said reference tap and the input of said error difference circuit to which the quantized output of said combining means is normally connected and in substitution therefor.

Claim 10

The combination of claim 7 and a fixed attenuator connectible during presetting between any tap at which a nonzero reference state is desired and the input of said error difference circuit.