Pulse Filtering for D/A Converter
Original Publication Date: 1985-Jul-01
Included in the Prior Art Database: 2005-Feb-18
An implementation of pulse filtering is disclosed for signal reconstruction with minimal distortion and minimal sampling points. Specifically, a circuit is illustrated to implement the reconstruction of a pulse amplitude modulation (PAM) signal. An ideal pulse is illustrated in Fig. 1 where Fig. 1a represents a function f(t) and its spectrums. Fig. 1b is a string of unit impulse functions, and its frequency domain. Note the spacing of the impulse functions is T where 2f = W = 2W T N M which is the Nyguist rate. Fig. 1c is the product of the 2 above functions on the time domain, and convolution in the frequency domain. Fig. 1d shows the narrow pulse q(t) and its frequency domain. Fig. 1e shows the distortion in the frequency domain when we use a non-impulse function for PAM.