Apparatus and method for converting a low voltage AC wiring circuit to a high speed data communications link
An apparatus for converting a low voltage alternating current (AC) wiring circuit to a high speed data communications link, comprising a primary coupling circuit and a secondary coupling circuit. The apparatus provides low voltage AC power to a data device and couples data signals between the data device and the AC power line via the converted low voltage AC wiring circuit. An example is provided for retrofitting a door chime system to a high speed data link such as a video camera system.
1. Apparatus for converting a doorbell wiring circuit to a high speed data communications link, comprising:
an entry unit coupled to the doorbell wiring circuit at an entrance of a building and further including a video camera coupled to the doorbell wiring circuit for producing a video image of a visitor at the entrance and providing a signal output on the doorbell wiring circuit; and
a transceiver unit coupled to the doorbell wiring circuit at a location of a door chime unit in the building; the transceiver further comprising:
a receiving circuit, for receiving the signal output from the doorbell wiring circuit and converting the signal output to wireless data; and
a transmitting circuit for transmitting the wireless data to a monitor unit within the building.
2. The apparatus of claim 1 , wherein the entry unit comprises:
an encoder for encoding the video image from the camera into the signal output for transmission on the doorbell wiring circuit; and
a control processor having control outputs coupled to the video camera and the encoder.
3. The apparatus of claim 2 , wherein the control processor includes first and second control terminals coupled to a doorbell switch for operating the door chime.
4. The apparatus of claim 1 , wherein the receiving circuit comprises:
an interface circuit coupled between the doorbell wiring circuit and the receiving circuit; and
a data converter having an input coupled from an output of the receiving circuit and providing a wireless data output.
5. The apparatus of claim 4 , wherein the transmitting circuit comprises:
a transmitter having an input coupled to the wireless data output and an output coupled to an antenna for emitting a wireless signal to the monitor unit within the building.
6. The apparatus of claim 1 , wherein the entry unit further comprises:
a battery for supplying operating voltages to the entry unit.
7. The apparatus of claim 1 , wherein the entry unit comprises:
an audio transducer for detecting and emitting sound at the entrance and having a sound output coupled to a sound input of the encoder.
8. The apparatus of claim 7 , wherein signals present at the sound input of the encoder are combined in the encoder with the video image.
9. The apparatus of claim 1 , wherein the transceiver unit is coupled to a standard AC power line via a step down transformer.
10. The apparatus of claim 9 , wherein the step down transformer is an existing transformer provided with an existing low voltage AC control circuit selected from the group consisting of a doorbell chime system, a security alarm system and a HVAC system.
11. The apparatus of claim 1 , wherein the entry unit further comprises a power source selected from the group consisting of solar power, signal-derived power, storage capacitor and AC line supplied power.
12. The apparatus of claim 2 , wherein the control processor includes first and second control terminals coupled to a doorbell switch for activating the entry unit.
13. The apparatus of claim 2 , wherein the control processor includes first and second control terminals coupled to a hands-free sensor device providing an output signal for activating the entry unit.