| 摘要 |
In a high speed QAM data communications receiver of the type adapted to receive bursts of signals having a bandwidth B Hz and sent at a predetermined rate of 1/T signals per second over a channel, wherein the receiver includes an automatic adaptive equalizer having taps spaced equally apart, tap coefficient circuitry for repeatedly multiplying the output of each tap by a respective tap coefficient, and adjustment circuitry for adjusting the tap coefficients, and output circuitry responsive to the equalizer for providing output signals at times kT + tau , k = 0, 1, . . . , where tau is a timing epoch, that improvement wherein the taps are spaced apart by T/n seconds, where n is greater than TB, and control circuitry is provided for early actuation of the adjustment circuitry to begin adjustment of the tap coefficients and hence training of the equalizer regardless of the initial value of the timing epoch, whereby the data capacity of the receiver is increased by reduction of the time required for set up of the receiver. |
