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# Pattern Generator (Chirp) (G Dataflow)

Version:

Generates a signal containing a chirp pattern.

## amplitude

Amplitude of the pattern.

Default: 1

## f1

Beginning frequency of the pattern in normalized units of cycles/sample.

Default: 0

## f2

Ending frequency of the pattern in normalized units of cycles/sample.

Default: 0.5

## error in

Error conditions that occur before this node runs. The node responds to this input according to standard error behavior.

Default: No error

## dt

Sampling interval.

Default: 1

## samples

Number of samples in the signal.

Default: 128

## chirp pattern

Output chirp pattern. The output pattern contains frequency ramping from f1*fs to f2*fs, where fs is the sampling rate.

## error out

Error information. The node produces this output according to standard error behavior.

## Algorithm for Generating the Chirp Pattern

If the sequence Y represents chirp pattern, this node obtains the elements of Y using the following equation:

${y}_{i}=A*\mathrm{sin}\left(\left(0.5*a*i+b\right)*i\right)$

$\text{for}\text{\hspace{0.17em}}i=0,\text{\hspace{0.17em}}1,\text{\hspace{0.17em}}2,\text{\hspace{0.17em}}...,\text{\hspace{0.17em}}n-1$

where

• A is the amplitude
• $a=2\pi \left(\text{f2}-\text{f1}\right)/n$
• $b=2\pi \text{f1}$
• f1 is the beginning frequency in normalized units of cycles/sample
• f2 is the ending frequency in normalized units of cycles/sample
• n is the number of samples

Where This Node Can Run:

Desktop OS: Windows

FPGA: Not supported