Patent ID: 7272368

Claim:
A receiver for receiving a narrow frequency deviation frequency modulated or phase modulated base band signal comprising: a mixer for mixing the received narrow frequency deviation signal to generate an intermediate frequency signal; a band pass filter for filtering the intermediate frequency signal; a narrow band discriminator circuit that performs a time domain expansion of the modulation deviation of the intermediate frequency signal and discriminates the base band signal comprising: an analog to logic level converter for receiving a reduced deviation modulated signal; a pulse generator that generates pulses with a fixed duration of one half the center frequency period of the intermediate frequency signal; an exclusive-OR gate that receives an output of the logic level converter and the pulse generator; an AND gate that receives an output of the exclusive-OR gate and a clock signal on each of its inputs; a counter comprising an up/down input for indicating whether the counter counts up or down and is attached to the analog to logic level converter output, a clock input attached to the AND gate output, and a clear input attached to a control circuit, the counter further comprising N parallel outputs; a latch comprising N parallel inputs and connected to the N parallel outputs of the counter and further comprising a clock input attached to an output of the control circuit and N parallel outputs; and wherein the control circuit clocks the data from the counter to the latch on the positive transition of the intermediate frequency signal, and sequentially clears the counter.