In this paper a closed-form approximated
expression is proposed for the Intersymbol Interference (ISI) as a function of
time valid during the entire stages of the non-blind adaptive deconvolution
process and is suitable for the noisy, real and two independent quadrature
carrier input case. The obtained expression is applicable for type of channels
where the resulting ISI as a function of time can be described with an
exponential model having a single time constant. Based on this new expression
for the ISI as a function of time, the convergence time (or number of iteration
number required for convergence) of the non-blind adaptive equalizer can be
calculated. Up to now, the equalizer’s performance (convergence time and ISI as
a function of time) could be obtained only via simulation when the channel
coefficients were known. The new proposed expression for the ISI as a function
of time is based on the knowledge of the initial ISI and channel power (which
is measurable) and eliminates the need to carry out any more the above
mentioned simulation. Simulation results indicate a high correlation between
the simulated and calculated ISI (based on our proposed expression for the ISI
as a function of time) during the whole deconvolution process for the high as
well as for the low signal to noise ratio (SNR) condition.
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