Abstract: A method is disclosed for detecting packet at a receiving system in a Multi-Carrier Modulation (MCM) system. The method starts with receiving a signal at the receiving system. Then during the plurality of symbol durations, a set of phases of the signal for each symbol duration is obtained, where each phase is a phase of a carrier of the number of carriers. Then a set of phase variances for each carrier of the number of carriers is obtained, where each phase variance is a difference of phases of a carrier in different symbol durations. Then a phase variance value based on the set of phase variances is computed and it is compared with a threshold to determine whether a packet has been detected from the received signal.

Abstract: A method is disclosed for detecting packet at a receiving system in a Multi-Carrier Modulation (MCM) system. The method starts with receiving a signal at the receiving system. Then a deviation value of the signal is computed, where the deviation value is computed at least partially based on phase differences between some number of carriers in the preamble. The deviation value is compared with a threshold to determine whether a packet has been detected from the received signal. In response to the determination that a packet has been detected, a symbol offset is computed optionally, where the symbol offset indicates a number of sample points from a beginning of a symbol.

Abstract: Embodiments of the invention include an apparatus for performing Galois multiplication using an enhanced Galois table. Galois multiplication may include converting a first and second multiplicand to exponential forms using a Galois table, adding the exponential forms of the first and second multiplicands, and converting the added exponential forms of the first and second multiplicands to a decimal equivalent binary form using the Galois table to decimal equivalent binary result of the Galois multiplication.

Abstract: A Power Line Communication (PLC) device that is resilient to cross-band interference. The PLC device is configured to communicate on AC power wiring in the frequency range of 9 kilohertz to 500 kilohertz and does not use automatic gain control prior to analog-to-digital conversion. The PLC device includes an over-sampled analog-to-digital converter with a sample clock of at least 10 megahertz and includes a loop filter that maintains a noise power spectral density that does not exceed three decibels above a minimum noise floor, of the noise power spectral density, at 80 kilohertz or above, and a digital filter and decimator configured to remove quantization noise, where a decimation factor of the decimator is such that it provides an output decimation rate between 350 kilohertz and 1.6 megahertz.

Abstract: A three-way or four-way switching circuit for lighting, and the like, is described. One three-way switch is replaced with an electronic switch. Both legs of the switching circuit are powered all the time and current is sensed in the legs to determine when one of the three-way or four-way switches has been switched. This information is used to turn the light on and off.

Abstract: In a power grid capable of electrical power delivery and power line communications, a distribution transformer and at least one smart meter is connected to the power grid. In one embodiment, the distribution transformer is configured to map the smart meters on the power grid to a virtual grid based upon measurements of signal metrics received from the various smart meters on the power grid, and the virtual grid is used to determine if a failure has occurred on the physical grid. A communications failure between nodes on the grid suggests a possible power failure, and the failure can be located using mapping information obtained from the virtual grid. A drop in power consumption on the power grid corroborates outages detected via the communications failure. In one embodiment, a cross phase delta value is computed to adjust the signal strength metrics measured between nodes having differing phases of electrical distribution.

Abstract: A method is disclosed for detecting packet at a receiving system in a Multi-Carrier Modulation (MCM) system. The method starts with receiving a signal at the receiving system. Then a deviation value of the signal is computed, where the deviation value is computed at least partially based on phase differences between some number of carriers in the preamble. The deviation value is compared with a threshold to determine whether a packet has been detected from the received signal. In response to the determination that a packet has been detected, a symbol offset is computed optionally, where the symbol offset indicates a number of sample points from a beginning of a symbol.

Abstract: A method is disclosed for detecting packet at a receiving system in a Multi-Carrier Modulation (MCM) system. The method starts with receiving a signal at the receiving system. Then during the plurality of symbol durations, a set of phases of the signal for each symbol duration is obtained, where each phase is a phase of a carrier of the number of carriers. Then a set of phase variances for each carrier of the number of carriers is obtained, where each phase variance is a difference of phases of a carrier in different symbol durations. Then a phase variance value based on the set of phase variances is computed and it is compared with a threshold to determine whether a packet has been detected from the received signal.

Abstract: A method implemented in a device is disclosed for networking through signals transmitted across a shared medium network. The method starts with monitoring for a first signal on a shared medium of the shared medium network. The first signal is processed after it is received and while the first signal is being processed, a set of one or more signals is received on the shared medium. Then a set of one or more amplitude increases is determined, where each amplitude increase is from an earlier received signal to a later received signal. The set of one or more amplitude increases is compared to a threshold value and at least partially in response to the comparison, the device discards one or more signals from the first signal and the set of one or more signals.

Abstract: A retainer pin is described for retaining, in one embodiment, a relatively thin blade against a transverse surface. The pin has a transition section which extends through an opening in the blade, a keeper section extending along one side of the blade, and a snap arm and snap end extending along an opposite side of the blade with a snap snapping over the edge of the blade.

Abstract: A method for automated topology discovery and management of meter nodes in a power grid is described. In the discovery mode any of the meter nodes is able to act as a proxy for a data concentrator to sort out the topology, and to determine the best path for communicating between a concentrator and each of the meter nodes.

Abstract: One embodiment of the invention employs techniques for the self-installation of network devices using fire-and-forget principles. These devices modify their own network configuration data, but do not modify the network configuration data of other devices. Utilizing fire-and-forget principles, the need for a central database and central authority on the network is not required but may still be used.

Abstract: A method is described for selecting repeaters comprising: transmitting a first signal from a first node to a second node; measuring signal strength of the first signal at the second node; transmitting a second signal from the second node to the first node; measuring signal strength of the second signal at the first node; and selecting the second node as a repeater based on the signal strength of the first signal and/or the signal strength of the second signal. Another embodiment of the method comprises: calculating signal strength of a signal transmitted to each of a plurality of nodes (the signal strength being measured at each node of the plurality); and selecting one or more of the nodes to be a repeater if the signal strength is below a maximum threshold value and above a minimum threshold value.

Abstract: An improved meter and its operation is described. The meter can be a part of a larger automated meter reading process that allows for remote reading of the meter though power line communication. Using a microcomputer core, the meter processes incoming analog data and can calculate several relevant data values need by utility providers. The meter can also be used to monitor and detect tampering dry connect/voltage free devices, such as gas and water meters, connected to the meter.

Abstract: A three-way or four-way switching circuit for lighting, and the like, is described. One three-way switch is replaced with an electronic switch. Both legs of the switching circuit are powered all the time and current is sensed in the legs to determine when one of the three-way or four-way switches has been switched. This information is used to turn the light on and off.

Abstract: A receiver particularly suited for an M-BUS is described. During transmission, the receiver is disabled. After each transmission, nodes and states in the receiver are set to prepare the receiver to receive a signal. Once data is sensed, a feedback loop clips the input signal to the receiver to limit the swing of the input signal. The line of the power supply at the lower potential is modulated, rather than modulating the line at the higher potential, for the transmission of data.

Abstract: A communications transformer in which the primary and secondary windings are each divided into equal halves is disclosed. One primary and one secondary half winding is disposed about one section of a magnetic core, while the other halves are disposed about a second, parallel section. Voltages in the primary half windings and secondary half windings caused by stray magnetic fields are subtracted.

Abstract: A power supply providing current interruption based on the energy from the supply over a sliding window of time is disclosed. The output current from the supply is periodically reestablished.

Abstract: A method is described for selecting repeaters comprising: transmitting a first signal from a first node to a second node; measuring signal strength of the first signal at the second node; transmitting a second signal from the second node to the first node; measuring signal strength of the second signal at the first node; and selecting the second node as a repeater based on the signal strength of the first signal and/or the signal strength of the second signal. Another embodiment of the method comprises: calculating signal strength of a signal transmitted to each of a plurality of nodes (the signal strength being measured at each node of the plurality); and selecting one or more of the nodes to be a repeater if the signal strength is below a maximum threshold value and above a minimum threshold value.

Abstract: An improved meter and its operation is described. The meter can be a part of a larger automated meter reading process that allows for remote reading of the meter though power line communication. Using a microcomputer core, the meter processes incoming analog data and can calculate several relevant data values need by utility providers. The meter can also be used to monitor and detect tampering dry connect/voltage free devices, such as gas and water meters, connected to the meter.