Dsp notation  (Page 2/3)

Signal

It is sometimes useful to describe an arbitrary signal, or an input/output relationship. In such cases, it is recommendedthat $f$ be used to represent a generic signal. For an input/output relationship, use $x$ as an arbitrary input signal and $y$ as the arbitrary output signal. When writing out the signal as a function of somevariable, such as time, it can be represented as $x(t)$ for continuous-time signals and as $x(n)$ for discrete-time signals.

Special signals

There are several signals used often enough to merit special attention. They are presented here.

Impulse

The impulse, or Dirac-Delta function , should be presented as $$\delta (t)$$ in continuous-time and as $$\delta (n)$$ in discrete-time.

Unit step

The unit step should be presented as $$u(t)$$ in continuous-time and as $$u(n)$$ in discrete-time. These functions will be marked-up in MathML the same as the delta function above; however,rather than the $\delta$ symbol you will use $u$ .

Sinc

The sinc function should be represented as

Norm

The norm of a vector or function should be represented as $(x)$ For instance, the Euclidean norm (sometimes called the L2-norm) of a vector should be given by