Equalizer sample loading in voiceband data sets

A method for determining the Hilbert transform component values r(t) and r(t) of a received complex data signal at a plurality of time points spaced T/p seconds apart, the frequency spectrum of said signal being comprised of at least a first plurality of spectral lines spaced 2.pi./NT radians/second apart, said method comprising the steps of

• determining the Hilbert transform component values of said signal at Np initial ones of said time points, and
• determining the Hilbert transform component values of said signal at each remaining one of said plurality of time points as a function of the values thereof at a respective associated one of said initial time points.

A receiver adapted to receive a modulated signal, said receiver including

• first means for determining the value of said modulated signal at a predetermined number of time points spaced T/p seconds apart, said first means including sampling means (21, 23, 27, 28) for determining the value of said modulated signal at Np initial ones of said time points by sampling said modulated signal at p/T samples per second, and
• means (53, 55, 56, 57, 64, 65, 67, 71, 81) for multiplying the value of said modulated signal at each of said predetermined number of time points by a respective coefficient and for recovering the baseband component of said modulated signal in response to the sum of the resulting products,
• characterized in that said first means includes second means (301, 305, 308, 311) operative when said baseband component is a periodic signal of period NT seconds for determining the value of said modulated signal at each remaining one of said predetermined number of time points as a function of the value of said modulated signal at a respective one of said initial time points.

Apparatus for determining the Hilbert transform component values r(t) and r(t) of a received complex data signal at a plurality of time points spaced T/p seconds apart, the frequency spectrum of said signal being comprised of at least a first plurality of spectral lines spaced 2.pi./NT radians/second apart, said apparatus comprising

• first means (21, 23, 27, 28) for determining the Hilbert transform component values of said signal at Np initial ones of said time points, and
• second means (301, 305, 308, 311) for determining the Hilbert transform component values of said signal at each remaining one of said plurality of time points as a function of the values thereof at a respective associated one of said initial time points.