| 摘要 |
A technique for demodulating a message signal from an angle modulated carrier signal. A noncoherent, independent, periodic reference is generated to have a predetermined phase characteristic and which is noncoherent with and independent of the angle modulated carrier signal. The phase of the reference is then compared with the phase of the carrier to determine the message signal on the angle modulated carrier. The phase of the noncoherent, independent, periodic reference is associated with a measured value for the reference. The phase of the angle modulated carrier signal is associated with a voltage value for the angle modulated carrier signal. These values are measured and then compared to determine the message signal on the modulated carrier signal. Time variations of the comparison of values are directly related to the message signal in the case of a PM carrier. Changes in the time variations of the voltage comparison are related to the message signal for a FM carrier. A sawtooth variation is used as the reference and is generated with a clock and counter. Zero values of the angle modulated signal load the counter value into a storage register or a processor to create a measurement of the phase difference between the reference and the angle modulated signal.
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