Barker code

A Barker code is a sequence of N values of +1 and −1,:$a\_j$ for $j\; =\; 1,\; cdotcdotcdot,\; N$such that:$|sum\_\{j=1\}^\{N-v\}\; a\_j\; a\_\{j+v\}|\; le\; 1,$for all .

Here is a table of all known Barker codes, where negations and reversals of the codes have been omitted. A Barker code has a maximum autocorrelation of 1 (when codes are not aligned).

Barker codes of length 11 and 13 are used in direct-sequence spread spectrum and Pulse Compression Radar systems because of their low autocorrelation properties.

Barker codes utilize biphase modulation; that is, the change of phase in the carrier wave is 180 degreesFact|date=August 2008.

A Barker code resembles a discrete version of a continuous chirp, another low-autocorrelation signal used in other pulse compression radars.

ee also

* Pseudorandom number sequence

References

* [http://mathworld.wolfram.com/BarkerCode.html Barker Code] — Mathworld