Abstract: Various aspects of the instant disclosure are directed towards communicating symbols over a power line carrying alternating current, based upon frequency variations in the alternating current. In accordance with some embodiments, a line driver couples data-carrying symbols over the power line, via a waveform. Variations in the alternating current are monitored and used for defining data useful for providing steps of the waveform. The accessed data entries are used to drive a line driver for modulating alternating current on the power line to account for the variations.

Abstract: An apparatus is provided for data communication over power lines in a PLC system. The apparatus includes a data-coupling circuit configured to provide data to the power lines for transmission. The data-coupling circuit includes a DC-isolation circuit configured to isolate circuitry of the data-coupling circuit from the power lines. The apparatus also includes a feedback circuit connected to the DC-isolation circuit. The feedback circuit has a power-tap circuit on an endpoint side of the feedback circuit. The power-tap circuit is configured to provide a feedback signal indicative of an estimate of an amount of power, current, and/or voltage provided from the data-coupling circuit through the DC-isolation circuit and to the power lines. Based on the feedback the signal, the strength of a transmitted may be adjusted (e.g., to maintain constant signal strength).

Abstract: In one or more embodiments, an apparatus includes a first power-line communication circuit to communicate data with a second power-line communication circuit over power lines and using a communication protocol requiring that one of the first power-line communication circuit or the second power-line communication circuit join into regular communications in response to an initiation message received over the power lines. The first power-line communication circuit communicates data regularly with the second power-line communication circuit over the power lines after being joined into regular communications by an initiation message received over the power lines, the initiation message being communicated over the power lines at an initiation time interval, the initiation time interval being based on a random interval that is within an interval range and that is based on a relative time at which at least two of the plurality of endpoint devices are designated to join within an interval range.

Abstract: In a power-line communication system, a data processing electronic circuitry can receive a plurality of symbols from a plurality of endpoint circuits and over a plurality of communications channels on power lines in a power-line communication system. A first symbol of the plurality of symbols can be decrypted using a first decryption key that is assigned to a first endpoint circuit. From the first decryption, a first measure of error is computed that includes a first bit error rate. The first symbol is decrypted using a second decryption key that is assigned to a second endpoint circuit. From the second decryption, a second measure of error is computed that includes a second bit error rate. The first and second bit error rates are compared to a threshold error measure to determine validity.

Abstract: Aspects of the present disclosure are directed toward the use of broadcast transmissions to multiple endpoint devices. These broadcast transmissions can be particularly useful for reducing the communication bandwidth used during transmission of configuration data to the endpoint devices. In order to implement the broadcast communications, the present disclosure describes a mechanism for configuring targeted endpoint devices to be responsive to the broadcast communications. For instance, a configuration command can be sent to each of the targeted endpoint devices. The configuration command can include a virtual ID. The targeted endpoint devices can configure themselves to listen for subsequent broadcast messages addressed to the virtual ID. Configuration data can then be sent using the virtual ID and associated broadcast messages.

Abstract: Various aspects of the disclosure are directed to methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for identifying network events. In one aspect, a method includes monitoring signal characteristic values for signals transmitted over a communications channel of a power line communications system and determining that a signal level value for the channel is less than a threshold signal level value for the channel. In response to determining that the signal level value for the channel is less than the threshold signal level value for the channel, a signal to noise ratio for the communications channel is computer and it is determined that the signal to noise ratio for the channel exceeds a threshold value. In response to determining that the signal to noise ratio for the communications channel exceeds the threshold value, storing data received over the communications channel is stored as valid data.

Abstract: Aspects of the present disclosure are also directed towards a method that includes maintaining a transmission period which has a start time and an end time synchronized to metrological time. Further, this method, in response to the start time, begins transmission of a frame, which includes a plurality of symbols. This transmission occurs over power distribution lines that carry power using alternating current (AC). This method also includes synchronizing a transmission time for each symbol of the plurality of symbols according to a time-based parameter of the AC. In response to reaching an end of the frame, a synchronization symbol period is determined for a synchronization symbol, as a function of the transmission times, for the plurality of symbols and time from the end of the frame to the end time. The synchronization symbol is then transmitted on the power distribution lines.

Abstract: Various aspects of the instant disclosure are directed towards communicating symbols over a power line carrying alternating current, based upon frequency variations in the alternating current. In accordance with some embodiments, a line driver couples data-carrying symbols over the power line, via a waveform. Variations in the alternating current are monitored and used for accessing a lookup table that stores data entries that define data useful for providing steps of the waveform. The accessed data entries are used to drive a line driver with stepped data, and therein modulating alternating current on the power line with the data-carrying symbols at a frequency that is tied to the frequency of the alternating current.

Abstract: Various circuits and methods are disclosed for communications over AC power lines. In one example embodiment, a power line communication circuit includes an analog front end having a data-coupling circuit configured to communicatively couple communication signals to and from a set of AC power lines in the power line communication system. The analog front end also includes a noise reduction circuit that is coupled to the data-coupling circuit. The noise reduction circuit is configured to mitigate noise within a communication frequency band of the communication signals by filtering, from the communication signals, at least one frequency that is located outside of the communication frequency band and that has harmonics located within the communication frequency band. A receiver circuit is coupled to the noise reduction circuit and is configured to demodulate data from the communication frequency band of the filtered communication signals.

Abstract: Particular embodiments are directed towards a method for communicating time-based data in a power line communication system. The communication system utilized in the method includes: a command center; a collector device; and a plurality of endpoint devices. The method includes communicating, from the collector device, downstream data to the plurality of endpoint devices. This downstream communication utilizes a communication protocol that is relative to a collector network time, and is over a set of power distribution lines carrying alternating current (AC). The collector network time uses the local oscillator. The AC zero-crossing event can be used as a time base for other versions of the network time. Conceptually, the AC can be thought of as acting as a reference clock for maintaining these other network times, although the clocking function can be carried out in the digital realm, e.g., using a digital-signal processor (DSP).

Abstract: Aspects of the present disclosure are directed toward a system that includes a plurality of endpoint devices. Each endpoint device can be configured and arranged to monitor a plurality of communication channels carried over power distribution lines for data communications. The endpoint can detect setup communications that contain an endpoint identifier (ID) matching the endpoint. The endpoint then stores or assigns the organization ID (obtained from the detected communications) to itself. The endpoint configures itself to respond to subsequent operational communications based upon the organization ID. A command center is configured and arranged to transmit setup communications to endpoint devices. The setup communications can include one or more endpoint identifiers and the organization ID. The command center can also transmit operational communications to the plurality endpoint devices, the operational communications including the organization ID.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for transmitting data. In one aspect, a method obtains a baseline data rate for transmissions from a node that are received over a channel of a power line communications system and a set of available modulation techniques for the node. The set of available modulation techniques can include at least two modulation techniques with which the node is configured to encode data that are transmitted over the channel. Using the set of available modulation techniques, a modulation technique that is capable of providing at least the baseline data rate with at least a threshold confidence for the node is selected. In turn, data is provided to the node specifying the selected modulation technique.

Abstract: Aspects of the present disclosure are directed towards a circuit-based apparatus for receiving data communications over power distribution lines that carry power using alternating current (AC). The apparatus has a processing circuit that is configured and arranged to receive an input signal representing the data communications over power distribution lines. For a quadrature encoded signal, the input signal is separated into intermediary signals representing a real portion of and an imaginary portion. The processing circuit can then determine timing information from the real portion of and the imaginary portion. The intermediary signals can then be decimated according to a variable rate of decimation that is responsive to the determined timing information. The decimated intermediary signals are also filtered.

Abstract: In one or more embodiments, a data processing apparatus is configured to receive data symbols transmitted from one or more endpoint devices. Each of the data symbols is transmitted in a respective temporal position assigned for communication by one of the plurality of endpoints. The data processing apparatus is configured to recover data from two or more transmission(s)/retransmission(s) (of the same data) that are received in error and have different temporal positions. The corresponding data symbols in error are phase-aligned per a common reference point and energy is accumulated therefrom. The data processing apparatus discerns correct data values from the accumulated energy.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for detecting grid events. In one aspect, a method includes receiving signal characteristic data that specify signal characteristic values for signals that are received over each of a plurality of communications channels of a power line communications network. A determination is made that the signal characteristic values for the signals that are received over at least one of the communications channels are outside of a baseline signal value range. An endpoint that communicates over the at least one communications channel is identified, and a determination is made that a set of the signal characteristic values for the identified endpoint matches one of a plurality a grid event signatures for the identified endpoint. Data that identify the endpoint and a particular grid event that is represented by the matched grid event signature are provided.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for detecting a power outage. In one aspect, a status request requesting a status of a portion of a power distribution network is received, where the request includes a reference to a power meter that is located within the portion of the network. In response to the status request, a block of communications channels is selected, where the block includes a target communications channel over which a signal corresponding to the referenced power meter is received. In turn, an amplitude of the signal being received over the target communications channel is obtained. A determination is made whether the amplitude of the signal is less than an outage threshold and a status notification is provided that specifies the status of the portion of the power distribution network for which the status has been requested.

Abstract: Aspects of the present disclosure are directed toward the use of broadcast transmissions to multiple endpoint devices. These broadcast transmissions can be particularly useful for reducing the communication bandwidth used during transmission of configuration data to the endpoint devices. In order to implement the broadcast communications, the present disclosure describes a mechanism for configuring targeted endpoint devices to be responsive to the broadcast communications. For instance, a configuration command can be sent to each of the targeted endpoint devices. The configuration command can include a virtual ID. The targeted endpoint devices can configure themselves to listen for subsequent broadcast messages addressed to the virtual ID. Configuration data can then be sent using the virtual ID and associated broadcast messages.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for authenticating a communications source. In one aspect, a method includes decrypting a symbol that was received over a particular communications channel. The symbol is decrypted using a decryption key that is assigned to a particular endpoint that is assigned the particular communications channel. A measure of error is computed for the decrypted symbol. In turn, a determination is made whether the measure of error exceeds a threshold error measure. If the measure of error does not exceed the threshold error measure the decrypted symbol is identified as a valid symbol transmitted by the particular endpoint, and logged as such. If the measure of error exceeds the threshold error measure, the decrypted symbol is identified as a symbol from a different endpoint.

Abstract: Various aspects of the instant disclosure are directed towards a method for communicating time-based data in a power line communication system. In accordance with one or more example embodiments, firmware is downloaded to a multitude of endpoints over power distribution lines carrying alternating current (AC) power. Endpoint devices targeted for changes to stored firmware are grouped and the firmware is delivered in chunks to each group. As devices receive a particular chunk of firmware, the device advances to a next stage and provides information indicative of this stage, based upon which subsequent chunks of firmware are communicated. This occurs (e.g., on a daily cycle) until the endpoint has received all firmware for an update, after which the endpoint(s) are re-started using the firmware. Accordingly, such updates can be carried out in a cyclic and verifiable manner.

Abstract: In one or more embodiments, a data processing apparatus is configured to receive data symbols transmitted from one or more endpoint devices. Each of the data symbols is transmitted in a respective temporal position assigned for communication by one of the plurality of endpoints. The data processing apparatus is configured to recover data from two or more transmission(s)/retransmission(s) (of the same data) that are received in error and have different temporal positions. The corresponding data symbols in error are phase-aligned per a common reference point and energy is accumulated therefrom. The data processing apparatus discerns correct data values from the accumulated energy.