| 摘要 |
A demodulator for a biphase or quadriphase shift-keying system. The demodulator includes two AND gates for biphase demodulation. The AND gate is one which will provide an output signal if and only if the two input signals are in phase. Each of the AND gates forms a feedback with an injection locked oscillator. Therefore depending on the phase of the input signal, one or the other AND gate provides an output which is then injected at the proper phase into the injection locked oscillator. The output of the AND gates is fed to a data logic and envelope detector to recover the data. For quadriphase phase-shift keying, four AND gates are required. The circuit can be constituted either by transistors or by transferred electron devices sometimes called Gunn effect devices.
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