Walsh Hadamard (Not in Base Package)

Performs the real Walsh Hadamard transform. Details

X is an array of power of two length.
Walsh Hadamard {X} is the Walsh Hadamard transform of the input sequence.
error returns any error or warning from the VI. Refer to Signal Processing Error Codes for more information about these conditions.

Walsh Hadamard Details

Note  The Walsh Hadamard transform has similar properties to the more well-known Fourier transform, but the computational effort is considerably smaller.

The Walsh Hadamard transform is based on an orthogonal system consisting of functions of only two elements -1 and 1. For the special case of n = 4, the Walsh Hadamard transform of the signal

can be noted in the following matrix form

.

If and denote the Walsh Hadamard matrices of dimension and respectively, the rule is

,

where is meant in the element wise sense.

Note  The Walsh Hadamard transform fulfills the Convolution Theorem: WH{X*Y} = WH{X}WH{Y}.

The following diagram shows the Walsh Hadamard transform of a pulse pattern signal of length 256, delay 32, and width 64.