pulse shaping

In digital modulation, bandwidth is a function of the pulse shape g(t). Pulse shaping makes the signal fit inside a certain bandwidth. We may need to this because at high rates of modulation, there could be inter-symbol-interference from finite impulse response signals in the time domain.

If a pulse shaper g(t) is included in a basis function, then the bandwidth of the signal is exactly the bandwidth of g(t). The bandwidth is K/T where K is a constant and T is duration of the symbol.

Typically must preserve orthonormality when multiplied by a basis function