K-Autocorrelation And Its Applications

The standard autocorrelation measures similarities between a binary sequence and its any shifted form. In this paper, we introduce the concept of the k-autocorrelation of a binary sequence as a generalization of the standard autocorrelation. We give two applications of the k-autocorrelation. The first one is related the additive circulant codes over F-4 in coding theory. We use the k-autocorrelation to determine the minimum distance of additive circulant codes over F-4. The second one is related the (7, 3, 1)-BIBD in design theory. The k-autocorrelation coefficients give us information about the lines in the (7, 3, 1)-BIBD.