User`s guide

Analytic Signal
5-27
5Analytic Signal
Purpose Compute the analytic signal of a discrete-time input.
Library Transforms
Description The Analytic Signal block computes the complex analytic signal corresponding
to each channel of the real M-by-N input, u.
where and H{⋅} denotes the Hilbert transform. The real part of the
output in each channel is a replica of the real input in that channel; the
imaginary part is the Hilbert transform of the input. In the frequency domain,
the analytic signal retains the positive frequency content of the original signal
while zeroing-out negative frequencies and doubling the DC component.
The block computes the Hilbert transform using an equiripple FIR filter with
the order specified by the
Filter order parameter, n. The linear phase filter is
designed using the Remez exchange algorithm, and imposes a delay of n/2 on
the input samples.
The output has the same dimension and frame status as the input.
Sample-Based Operation
When the input is sample-based, each of the M∗N matrix elements represents
an independent channel. Thus, the block computes the analytic signal for each
channel (matrix element) over time.
Frame-Based Operation
When the input is frame-based, each of the N columns in the matrix contains
M sequential time samples from an independent channel, and the block
computes the analytic signal for each channel over time.
Dialog Box
yujH u{}+=
j
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