Method and apparatus for supplying power, and channeling analog measurement and communication signals over single pair of wires

摘要

Disclosed is a novel technique for transferring power, measurement signals, and communication signals between two electrical devices over a single wire pair. A host device supplies power to a sensor device over the wire pair. The sensor device obtains a/c measurement signals. The sensor device transmits the a/c measurement signals by modulating the current component of the power signal on the wire pair. The host device de-modulates the current component of the power signal on the wire pair to recover the a/c measurement signals. The sensor device generates a serial bit stream containing sensor communication signals, and modulates it with either the voltage- or current-component of the power signal present on the wire pair. The host device appropriately de-modulates the power signal to recover the serial bit stream containing the sensor communication signals. The host device may also generate a serial bit stream containing host communication signals. The host device modulates the serial bit stream with the other component (current- or voltage-component) of the power signal on the wire pair. The sensor device appropriately de-modulates the power signal to recover the serial bit stream containing the host communication signals.