Abstract: A pulse coding system is disclosed that includes an encoder for encoding the received analog signal as a series of output pulses, and a decoder for receiving the pulses output from the encoder and for generating an output signal corresponding to the analog signal received by the encoder. The encoder includes a first decaying signal source for generating a decaying reference signal, and a pulse-generating comparator circuit for receiving the analog signal to be encoded as well as the decaying reference signal. The pulse-generating comparator circuit compares the amplitudes of the received analog signal and the reference signal and generates and outputs a pulse whenever the amplitude of the decaying reference signal falls below that of the received analog signal. The first decaying signal source receives the generated pulses and responds to the pulses by increasing the amplitude of the decaying reference signal a predetermined amount each time a pulse is received.