In a digital communications receiver configured to receive, via a
communications channel, a received first signal representing a sequence
of symbols, each symbol being encoded to be representative of data bits,
a method of processing the received signal includes adjusting a
magnitude, filtering, and applying cyclic prefix restoration, to the
received signal to produce a second signal, converting the second signal
from time domain to frequency domain to produce a frequency domain
signal, and determining a first quantity of values representing a first
portion of the symbols by evaluating a relationship of channel values
representing characteristics of the communications channel and a second
quantity of values representing a portion of the frequency domain signal,
the first quantity being smaller than the second quantity.