A new straightforward method to compute glottal pulses from speech samples is presented. In the method the human speech production mechanism is modelled with three functional blocks: the source, the tract and the lip radiation. After cancelling the effect of the vocal tract and the lip radiation glottal pulses close to the natural shape are obtained. The method can be effectively applied to speech coding. Improvements of this new method as compared to conventional LPC-coders are discussed. Coding results of long vowels and short words consisting of vowels are presented.