a copy of a pulse into the pam baseband signal prior to frequency upconversion and power amplification the pulse comprises a function of or an extra copy of a pulse in the pam baseband signal the pulse injector analyzes the pam baseband signal for times when a predetermined threshold is exceeded and forms a pulse that is constructed and arranged to reduce the amplitude of the pam baseband signal to a desired peak amplitude when the pulse is added to the pam baseband signal application_number US 4268908 A description fig1 is a block diagram of a conventional pulse amplitude modulation pam signal generator 10 which is well known in the prior art many modern communication systems transmit digital messages using a scheme called pulse amplitude modulation pam a pam signal is a frequency upconverted sum of amplitude scaled phase shifted and time shifted versions of a single pulse the amplitude scaling and phase shifting of the n th time shifted version of the pulse are determined by the n th component of the digital message in the field of communications systems the broad class of pam signals includes signals commonly referred to as pam quadrature amplitude modulation qam and phase shift keying psk and many variants recognized by those skilled in the.