| 摘要 |
A data carrier signal is injected into the secondary terminals of a distribution transformer. In a cyclic manner, electric charge and energy are efficiently recovered from a part of the carrier signal waveform, stored momentarily, and then reused to boost the signal strength in another part of the waveform. This is achieved through the use of a resonant network of active and reactive components, which has been specially designed to enhance energy efficiency. Digital data is applied to the carrier through coherent frequency shift keying in a manner that preserves the energy recovery advantages of the carrier signal generating circuit. The signal frequency and amplitude is such that it appears with sufficient strength on the primary terminals of the distribution transformer, and can travel for miles. Both the transmitter and receiver circuits use the power line waveform as a timing reference to eliminate timing errors. The receiver uses a phase detector and a dual frequency reference signal generator to decode the data being sent. Superior performance is achieved in the receiver circuit through the use of digital methods to maintain frequency control, while employing analog methods for signal capture.
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