Frequency Discriminator translates incoming RF / Microwave signals into a monotonic output voltage that is proportional to the RF / Microwave frequency. Accurate frequency information can then be derived from the Output Voltage because a Delay Line Frequency Discriminator takes the Input RF / Microwave Signal and produces two RF / Microwave Signal components that have a phase shift that is proportional to the original input frequency at fixed power input levels. By summing the two signal components together and then using detection techniques produces a detected Output Voltage that is frequency dependent. Therefore, as the input RF / Microwave Signal frequency is varied so does the output voltage of the Delay Line Frequency Discriminator.
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