Apparatus for receiving low level digital signals transmitted over power lines
Patent 4633218 Issued on December 30, 1986. Estimated Expiration Date: 
December 30, 2003. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
December 30, 2003. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 2605359 2909606 Demodulation method and circuit for discretely modulated ac signals Central system for controlling remote devices over power lines Patent #: 4174517 InventorsAssigneeApplicationNo. 06/562646 filed on 12/19/1983US Classes:375/334, Frequency shift keying340/310.12Modulation techniqueExaminersPrimary: Olms, Douglas W.Assistant: Rokoff, Kenneth I. Attorney, Agent or FirmInternational ClassH04B 3/54 (20060101)AbstractDigital data is transmitted over AC power lines at typically a 300 baud rate and at a frequency of 130 kilohertz representing a binary ONE and 131 kilohertz representing a binary ZERO. Apparatus in the receiver relay including a quadrature detector converts the high frequency signals to digital binary signals which are applied to a microprocessor. The microprocessor generates signals to control relays in accordance with the information received from the AC power lines. | |
