  Traditional radio interferometric correlators produce regular-gridded samples
of the true $uv$-distribution by averaging the signal over constant, discrete
time-frequency intervals. This regular sampling and averaging then translate to
be irregular-gridded samples in the $uv$-space, and results in a
baseline-length-dependent loss of amplitude and phase coherence, which is
dependent on the distance from the image phase centre. The effect is often
referred to as "decorrelation" in the $uv$-space, which is equivalent in the
source domain to "smearing". This work discusses and implements a
regular-gridded sampling scheme in the $uv$-space (baseline-dependent sampling)
and windowing that allow for data compression, field-of-interest shaping and
source suppression. The baseline-dependent sampling requires irregular-gridded
sampling in the time-frequency space i.e. the time-frequency interval becomes
baseline-dependent. Analytic models and simulations are used to show that
decorrelation remains constant across all the baselines when applying
baseline-dependent sampling and windowing. Simulations using MeerKAT telescope
and the European Very Long Baseline Interferometry Network show that both data
compression, field-of-interest shaping and outer field-of-interest suppression
are achieved.
