Barker Code Generator (Communications Blockset)

Generate a Barker Code

Library

Sequence Generators sublibrary of Comm Sources

Description

Barker codes, which are subsets of PN sequences, are commonly used for frame synchronization in digital communication systems. Barker codes have length at most 13 and have low correlation sidelobes. A correlation sidelobe is the correlation of a codeword with a time-shifted version of itself. The correlation sidelobe, C_k, for a k-symbol shift of an N-bit code sequence, {X_j}, is given by

where X_jis an individual code symbol taking values +1 or -1, for , and the adjacent symbols are assumed to be zero.

The Barker Code Generator block provides the codes listed in the following table:

Code length
Barker Code

1
[-1]

2
[-1 1];

3
[-1 -1 1]

4
[-1 -1 1 -1]

5
[-1 -1 -1 1 -1]

7
[-1 -1 -1 1 1 -1 1]

11
[-1 -1 -1 1 1 1 -1 1 1 -1 1]

13
[-1 -1 -1 -1 -1 1 1 -1 -1 1 -1 1 -1]

Code length	Barker Code
1	`[-1]`
2	`[-1 1];`
3	`[-1 -1 1]`
4	`[-1 -1 1 -1]`
5	`[-1 -1 -1 1 -1]`
7	`[-1 -1 -1 1 1 -1 1]`
11	`[-1 -1 -1 1 1 1 -1 1 1 -1 1]`
13	`[-1 -1 -1 -1 -1 1 1 -1 -1 1 -1 1 -1]`

Dialog Box

Code length: The length of the Barker code.
Sample time: Period of each element of the output signal.
Frame-based outputs: Determines whether the output is frame-based or sample-based.
Samples per frame: The number of samples in a frame-based output signal. This field is active only if you select the Frame-based outputs check box.

See Also

PN Sequence Generator

AWGN Channel Baseband PLL