User`s guide

Signal Concepts

3-11

Multichannel Signals

The following figure shows the prototypical discrete-time signal discussed in

“Discrete-Time Signals” on page 3-3. If this signal were propagated through a

model sample-by-sample, rather than in batches of samples, it would be called

sample-based. It would also be called single-channel, because there is only one

independent sequence of numbers.

In practice, signal samples are frequently transmitted in batches, or frames,

and several channels of data are often transmitted simultaneously. Hence, the

general signal is frame-based and multichannel.

The following sections explain how sample-based and frame-based

multichannel signals are represented in Simulink:

•“Sample-Based Multichannel Signals”

•“Frame-Based Multichannel Signals”

The representation of single-channel signals follows naturally as a special case

(one channel) of the general multichannel signal.

Sample-Based Multichannel Signals

Sample-based multichannel signals are represented as matrices. An M-by-N

sample-based matrix represents M

∗N independent channels, each containing a

single value. In other words, each matrix element represents one sample from

a distinct channel.

As an example, consider the 24-channel (6-by-4) sample-based signal in the

figure below, where u

t=0

is the first matrix in the series, u

t=1

is the second, u

t=2

is the third, and so on.

time (s)

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