Abstract: An improved residential electrical energy system is described based on the use of a smart load center or power distribution panel configured to select the use of utility power or power derived from storage batteries independently for each of a number of load circuits based on availability of utility power and battery charge state information.

Abstract: In one aspect of the invention, an improved messaging service is described comprising a server for receiving messages from a first subscriber addressed to one or more second subscribers and storing them in a scrambled form on the server along with security tokens specific to each message and recipient subscriber to facilitate unscrambling only by the intended recipient subscribers. In a second aspect of the invention, a subscriber terminal is described for precalculating security tokens corresponding to each of a number of yet-to-be received messages and transmitting the security tokens to a server for scrambling said messages even when the receiving subscriber terminal is offline. A new-message originating terminal also receives from the server a precalculated and prestored security token for each of a number of intended recipients of the new message and combines them with a locally generated security token to form header information included with the new message.

Abstract: A wiring fault detector adapted specifically to address the requirement for arc fault protection specified in National Electrical Code (2011) article 690.11 comprises running at least one additional wire in parallel with the power conductors to be protected, thereby allowing evaluation at the location of a fault detector of an electrical parameter indicative of conductor integrity along its whole length. In one implementation, the additional conductor allows the voltage drop across the power conductor to be measured and verified to be small and/or noise-free. In another implementation, the additional conductor is a redundant power conductor connected in parallel with the main power conductor, allowing verification that the current flow in both the main and the additional power conductors is partitioned in an expected ratio indicative of wiring integrity.

Abstract: A 1, 2 or 3-phase DC to AC converter system for reducing the cost of solar energy installations achieves cost reduction by eliminating low-frequency power transformers. One DC input polarity is selectively switched to an output terminal when the instantaneous AC output from a second output terminal is desired to be of the opposite polarity, while the other DC input polarity is used to form an approximation to a segment of a sine wave of the desired polarity at the second output terminal. A common-mode AC signal is thereby created on the balanced DC input lines at a frequency which is a multiple of 1, 2 or 3 times the AC output frequency and which is useful for detecting ground faults in the DC circuit.

Abstract: An acoustic noise canceling microphone arrangement and processor that uses a principal microphone and other microphones that may be incidentally or deliberately located in the vicinity of the principal microphone in order to derive an audio signal of enhanced signal-to-background noise ratio. In one implementation, the principal and incidental microphones comprise the microphone built into a mobile phone and the microphone built into a Bluetooth headset.

Abstract: A wiring fault detector adapted specifically to address the requirement for arc fault protection specified in National Electrical Code (2011) article 690.11 comprises running at least one additional wire in parallel with the power conductors to be protected, thereby allowing evaluation at the location of a fault detector of an electrical parameter indicative of conductor integrity along its whole length. In one implementation, the additional conductor allows the voltage drop across the power conductor to be measured and verified to be small and/or noise-free. In another implementation, the additional conductor is a redundant power conductor connected in parallel with the main power conductor, allowing verification that the current flow in both the main and the additional power conductors is partitioned in an expected ratio indicative of wiring integrity.

Abstract: Circuits and methods are disclosed for reducing interference from transmitter leakage in a radio transceiver. An exemplary method for reducing interference from transmitter leakage in a radio transceiver comprises downconverting, filtering, and sampling a radio frequency signal comprising a desired signal and a transmitter leakage signal to obtain a sampled signal of interest. The method further comprises generating a sampled distortion signal estimate that estimates one or more distortion products of the transmitter leakage signal, such as a squared amplitude obtained from a square-law device or corresponding digital function. Finally, the method comprises combining the sampled distortion signal estimate with the sampled signal of interest to obtain interference-reduced signal samples.

Abstract: In one aspect of the invention, a communications device is described to include novel software for aggregating voice and other messages from various communications media and presenting the user with a display of same, ordered by medium, date of receipt, source etc. The software also comprises a user-friendly man-machine interface for forwarding the messages from one medium to another, including making such messages available to members of social websites. In a second aspect of the invention, a server computer is described, including software to receive, organize and store said messages in digital form, with the participation of the user's communication device in one mode and automatically without the participation of the user's device in another mode. The server comprises software that generates links to selected stored messages that the user can post on the Web.

Abstract: An improved solar energy utilization system is described based on the use of a smart load center which can automatically select the use of utility power or solar-derived power independently for each of a number of load circuits based on availability of utility and solar power, preset user priorities, battery charge status, time of day, instantaneous consumption, historical consumption patterns and weather forecasts.

Abstract: Systems for transmitting information symbols utilize ternary codes or pivot codes in conjunction with spread spectrum encoding. The systems comprise at least a first symbol source for supplying an information signal comprising at least a first stream of I,Q bit pairs, means for using either a ternary code or at least one pivot code for spreading the at least first stream of I,Q bit pairs and thereby respectively forming first chips and second chips, and a radio signal modulator for transmitting the first chips and second chips over a radio interface.

Abstract: The coupling circuit described herein comprises passive analog components for coupling a transceiver to an antenna, such as an antenna array. The coupling circuit transforms an input signal into an appropriate format for each element of the antenna array. The coupling circuit comprises a coupling network having a plurality of inputs and a plurality of outputs. The inputs provide quadriphase versions of at least one input signal. In one embodiment, the coupling circuit performs a Discrete Fourier Transform (DFT) on the input signal. In another embodiment, the coupling circuit performs a Fast Fourier Transform (FFT) on the input signal. In still another embodiment, the FFT performed by the coupling circuit implements a Butler matrix.

Abstract: Exemplary embodiments comprise memory for storing the look-up table values. One exemplary memory comprises a decoder, an encoder, and one or more patterns of crisscrossed interconnect lines that interconnect the encoder with the decoder. The patterns of crisscrossed interconnection lines may be implemented on one or more planar layers of conductor tracks vertically interleaved with isolating material.

Abstract: A wiring fault detector adapted specifically to address the requirement for arc fault protection specified in National Electrical Code (2011) article 690.11 comprises running at least one additional wire in parallel with the power conductors to be protected, thereby allowing evaluation at the location of a fault detector of an electrical parameter indicative of conductor integrity along its whole length. In one implementation, the additional conductor allows the voltage drop across the power conductor to be measured and verified to be small and/or noise-free. In another implementation, the additional conductor is a redundant power conductor connected in parallel with the main power conductor, allowing verification that the current flow in both the main and the additional power conductors is partitioned in an expected ratio indicative of wiring integrity.

Abstract: The described method characterizes scattering objects in a wireless channel. The present invention determines non-equally spaced path delays and Doppler parameters for a plurality of scattering objects in a wireless channel. More particularly, a frequency-to-time transform applied to a plurality of OFDM pilot samples received over a plurality of OFDM symbol periods generates a set of non-equally spaced path delays and a set of associated complex delay coefficients. Further, a time-to-frequency transform applied to the complex delay coefficients determined for one path delay over multiple OFDM symbol periods generates a set of Doppler parameters comprising a plurality of non-equally spaced Doppler frequencies and their corresponding scattering coefficients for that path delay.

Abstract: Methods, software and apparatuses for decoding received delayed path signals are described. A receiver receives a signal via different paths with relative delay, e.g., on the same frequency channel. The signal is sampled at at least one sample per symbol. A channel estimator determines channel coefficients associated with the channel over which the signals were transmitted. A processor selects samples that include a dependence on a particular symbol being decoded and computes an error metric for each possible value of the particular symbol, for combinations of hypothesized future symbol values on which the selected samples depend, and for single values of previous symbols on which the selected samples depend. Error metrics calculated for each symbol are stored in memory. A soft symbol is generated based on said signal samples from the sampler, the channel coefficients and estimates of symbols computed.

Abstract: Exemplary embodiments comprise memory for storing the look-up table values. One exemplary memory comprises a decoder, an encoder, and one or more patterns of crisscrossed interconnect lines that interconnect the encoder with the decoder. The patterns of crisscrossed interconnection lines may be implemented on one or more planar layers of conductor tracks vertically interleaved with isolating material.

Abstract: Methods and apparatus are disclosed for automatically adjusting antenna impedance match in a wireless transceiver employing phase-amplitude modulation. According to some embodiments of the invention, a wireless transceiver comprises a transmitter circuit and a receiver circuit connected to the antenna by a transmit/receive duplexer. An electronically adjustable matching network is located between the transmitter output and the antenna. To control the adjustable matching network, a directional coupler is located between the transmitter output and the matching network to separate transmit signals reflected from the antenna system, including the antenna, the matching network and the T/R duplexer. The reflected transmit signals are routed to the receiver circuit, which digitizes the reflected signal and determines an antenna reflection coefficient based on the digitized reflected signal and the modulation signal used to create the transmit signal.

Abstract: A method and apparatus for compensating for ISI is described herein. A transmitter and receiver work together to develop pulse shaped OFDM symbols with reduced inter-channel ISI between pulse-shaped OFDM symbols transmitted on different sub-carriers at the same time, and inter-block ISI between pulse-shaped OFDM symbols transmitted on the same sub-carrier at different times. In addition, a pre-compensation element in the transmitter and/or a post-compensation element in the receiver compensate for diagonal ISI occurring between pulse-shaped OFDM symbols transmitted on different sub-carriers at different times.

Abstract: A method and apparatus for configuring a variable filter in an OFDM transmitter based on the number of subcarrier frequencies selected for the input data block is described herein. An exemplary OFDM transmitter comprises a control unit, OFDM modulator, and variable filter. The control unit selects the number of subcarriers for the input data block, and configures one or more filter properties for the variable filter based on the selected number of subcarriers. The modulator, which has a size greater than the selected number of subcarriers, pads an input data block generated for the selected number of subcarriers to generate an expanded data block having a size equal to the size of the modulator, and modulates the expanded data block to generate an OFDM signal. The filter, as configured by the control unit, filters the OFDM signal.

Abstract: Exemplary embodiments of the present invention comprise a method for compressing data for storage in memory. According to one embodiment, the method forms a set of values based on a monotonically ordered series of look-up table values. For one or more paired values in the set, the exemplary method generates a difference of the values in the pair. After replacing one of the values in the pair with a value based on the differences to modify the set, the exemplary method stores final values based on the modified set in memory. The present invention also comprises memory for storing the look-up table values. One exemplary memory comprises a decoder, an encoder, and one or more patterns of crisscrossed interconnect lines that interconnect the encoder with the decoder. The patterns of crisscrossed interconnection lines may be implemented on one or more planar layers of conductor tracks vertically interleaved with isolating material.