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| Number | Title | Issue Date |
| 7969298 | Inbound interference reduction in a broadband powerline system Disclosed is a method and apparatus for reducing inbound interference in a broadband powerline communication system. Data modulated on first and second carrier frequencies is received via respective first and second lines of the powerline system. A characteristic of... | 06/28/2011 |
| 7453353 | Inbound interference reduction in a broadband powerline system Disclosed is a method and apparatus for reducing inbound interference in a broadband powerline communication system. Data modulated on first and second carrier frequencies is received via respective first and second lines of the powerline system. A characteristic of... | 11/18/2008 |
| 7323831 | Illumination device An illumination device has an illumination unit which glows when current flows through a load thereof, at least one instruction unit for instructing the illumination unit to glow, a PWM signal generating unit which generates a plurality of PWM signals based on that ... | 01/29/2008 |
| 7307520 | Systems and methods for direct current system digital carried message conveyance The systems and methods of the present invention provide for conductive emissions communication without requiring dedicated communications wires. The systems and methods have the capability to send digital messages over the same wires that are used to power DC syste... | 12/11/2007 |
| 7262695 | Network interface device An apparatus is disclosed that provides a gateway function. The apparatus has an enclosure surrounding a network interface device. The network interface device has a communications network interface to a communications network and a power line network interface to a... | 08/28/2007 |
| 7215245 | Activator circuit responsive to power line disturbances An activator circuit responsive to power line disturbances. In condition of false alarm, the user will toggle a local light switch causing electrical disturbances on the power line. The activator circuit detects these disturbances and activates an output, which is f... | 05/08/2007 |
| 7199706 | PLC intercom/monitor A digital intercom device consistent with certain embodiments uses power line communication (PLC). A power line interface connects to a power line serving as a communication medium. An audio codec is coupled to the power line interface for encoding and decoding digi... | 04/03/2007 |
| 7091849 | Inbound interference reduction in a broadband powerline system Disclosed is a method and apparatus for reducing inbound interference in a broadband powerline communication system. Data modulated on first and second carrier frequencies is received via respective first and second lines of the powerline system. A characteristic of... | 08/15/2006 |
| 7091831 | Method and apparatus for attaching power line communications to customer premises A method and apparatus for modifying a power distribution network in a building in order to provide data communication by using a Power Line Carrier (PLC) signal to an approximate electrical central location point of a power distribution system remote from the data ... | 08/15/2006 |
| 4755792 | Security control system A security and control system for use in a home or building which utilizes a coded audio link between the entry detectors/transmitters and the relay modules, and a digital pulse coded power line communication ("PLC") link between the relay modules and the... | 07/05/1988 |
| 4697166 | Method and apparatus for coupling transceiver to power line carrier system A method and apparatus for efficiently coupling a transceiver to an AC power line transmission system. The preferred embodiment of the coupling system comprises a line coupling network and first and second filter ports. The first filter port is connected ... | 09/29/1987 |
| 4580276 | System and method for transporting data A private local area network (LAN) is created for use with a variety of transmission media for the purpose of exchanging data preassigned addresses, and control signals according to simplified protocols. The LAN members can consist of any combination of c... | 04/01/1986 |
| 4569045 | 3-Wire multiplexer The invention provides a 3-wire multiplexing system exhibiting high noise immunity, particularly suitable for industrial control applications. A master station provides AC power, and clocking and synchronization information, for a plurality of remote tran... | 02/04/1986 |
| 4422073 | Combustible gas detection system A combustible gas detection system in which analog signals produced by a remotely located combustible gas sensor are converted to digital signals at the sensor and the digital signals control a coherent frequency shift keying modulator which impresses alt... | 12/20/1983 |
| 4414534 | Radio frequency detection circuitry having noise discrimination capability In a radio frequency detector, a high pass filter is provided to attenuate any undesired low frequencies present in signals applied to the filter. The filter output serves as an input to an AND gate. A low pass filter directs power line voltage to a one-s... | 11/08/1983 |
| 4398178 | Apparatus for transmitting information on an alternating current line In a system for transmitting information on an a.c. line from a transmitter unit to a receiver unit which is connected to the line at a great distance from the a.c. source supplying said line than the transmitter unit, information is transmitted on one of... | 08/09/1983 |
| 4383243 | Powerline carrier control installation A powerline carrier control installation includes a control transmitter with an audio frequency output voltage, an isolation transformer, a coupling capacitor for parallel coupling to an a-c voltage network, and a device for suppressing a line frequency b... | 05/10/1983 |
| 4348657 | Method for transmitting binary signals over a foreign wiring network A method for transmitting binary signals having two logical states over a foreign wiring network, in particular for transmitting signals between structural elements of an alarm installation over an electrical supply wiring network. At least one of the two... | 09/07/1982 |
| 4344066 | Noise trap arrangement for AC power line communication systems A noise trap circuit which suppresses noise in a communication system of the type used in hotels and motels to transmit encoded communication signals such as room status information. The communication signals are transmitted on the neutral and ground line... | 08/10/1982 |
| 4307380 | Transmitting signals over alternating current power networks This invention relates to communication systems of the type particularly useful in power line communications. Signals to be transmitted, which can be in the form of short, fixed frequency signals, are expanded in time and/or bandwidth to provide a longer ... | 12/22/1981 |
| 4130861 | Power line carrier noise elimination A method and apparatus are provided for eliminating noise signals from power transmission lines utilized for transmitting information signals in power line carrier systems. Use is made of the principle that signals transmitted line-to-ground are more seve... | 12/19/1978 |
| 4123748 | Burglar alarms utilizing ultrasonic waves Burglar alarms utilizing ultrasonic waves in which ultrasonic waves transmitted from a wave transmitting oscillator are reflected by such objects as doors, windows, floors, walls, etc. and such reflected ultrasonic waves will be received by a wave receivi... | 10/31/1978 |
