User`s guide

Delay Line
5-124
5Delay Line
Purpose Rebuffer a sequence of inputs with a one-sample shift.
Library Signal Management / Buffers
Description The Delay Line block buffers the input samples into a sequence of overlapping
or underlapping matrix outputs. In the most typical use (sample-based inputs),
each output differs from the preceding output by only one sample, as
illustrated below for scalar input.
Note that the first output of the block in the example above is all zeros; this is
because the
Initial Conditions parameter is set to zero. Due to the latency of
the Delay Line block, all outputs are delayed by one frame, the entries of which
are defined by the
Initial Conditions parameter.
Sample-Based Operation
In sample-based operation, the Delay Line block buffers a sequence of
sample-based length-N vector inputs (1-D, row, or column) into a sequence of
overlapping frame-based M
o
-by-N matrix outputs, where M
o
is specified by the
Delay line size parameter (M
o
>1). That is, each input vector becomes a row in
the frame-based output matrix.
At each sample time the new input vector is added in the last row of the output,
so each output overlaps the previous output by M
o
-1 samples. Therefore, the
output sample period and frame period is the same as the input sample period
(T
so
=T
si
, and T
fo
=T
si
). When M
o
=1, the input is simply passed through to the
output and retains the same dimension, but becomes frame-based. The latency
of the block always causes an initial delay in the output; the value of the first
output is specified by the
Initial conditions parameter (see “Initial
Conditions” below). Sample-based full-dimension matrix inputs are not
accepted.
The Delay Line block’s sample-based operation is similar to that of a Buffer
block with
Buffer size equal to M
o
and Buffer overlap equal to M
o
-1, except
that the Buffer block has a different latency.
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4
5
6
0
1
2
(input samp
l
e perio
d
= T
si
)
(output samp
l
e perio
d
= T
si
)
1
2
3
2
3
4
3
4
5
0
0
1
0
0
0