Equalization arrangement

A voiceband data signal comprised of frequency-division-multiplexed primary and secondary channels is applied to the receiver portion of a modem. Circuitry within the modem for recovering the primary channel data includes an anti-aliasing filter, A/D converter, Hilbert filter, demodulator, fractionally-spaced equalizer, carrier recovery circuit and decision circuit. An error signal put out by the decision circuit is used by the equalizer to update its coefficients, and thus its transfer function. Rather than using a bandpass filter to remove the secondary channel energy prior to sampling and equalization, the receiver relies on the fractionally-spaced equalizer to suppress the secondary channel energy.