Abstract: Systems and methods for implementing coexistence by requesting access to a channel in power line communications (PLC) are described. In an illustrative embodiment, a method performed by a PLC device, such as a PLC meter, may include detecting a communication from foreign PLC device on a PLC network in response to a foreign preamble received by the PLC device, determining whether a threshold back-off duration has been reached, and transmitting a channel access request in response to a determination that the threshold back-off duration has been reached.

Abstract: A method of operating a transmitter (FIGS. 3A and 5A) is disclosed. The method includes receiving a sequence of data bits (DATA), wherein each data bit has a respective sequence number. A first data bit of the sequence is spread (508) with a first spreading code (504) determined by the sequence number (502) of the first data bit. A second data bit of the sequence is spread (508) with an inverse of the first spreading code (506) determined by the sequence number (502) of the second data bit. The first and second data bits are modulated (510) and transmitted (516) to a remote receiver.

Abstract: Systems and methods for enhanced carrier sense multiple access (CSMA) protocols are described. In various implementations, these systems and methods may be applicable to Power Line Communications (PLC). For example, a method may include attempting to access a communications channel to transmit a frame after a backoff time proportional to a randomly generated number within a contention window (CW), the CW having an initial value carried over from a previous transmission of a different frame. Additionally or alternatively, some of techniques described herein may facilitate the spreading of the time over which devices attempt to transmit packets, thereby reducing the probability of collisions using, for example, Additive Decrease Multiplicative Increase (ADMI) mechanisms.

Abstract: Systems and methods for implementing coexistence by requesting access to a channel in power line communications (PLC) are described. In an illustrative embodiment, a method performed by a PLC device, such as a PLC meter, may include detecting a communication from foreign PLC device on a PLC network in response to a foreign preamble received by the PLC device, determining whether a threshold back-off duration has been reached, and transmitting a channel access request in response to a determination that the threshold back-off duration has been reached.

Abstract: A wireless receiver for receiving signals from an interference-limited transmitter in an interference-limited system comprising at least one transmit antenna, where the signals comprise a plurality of symbols. The receiver comprises a plurality of receive antennas and collection circuitry for collecting a plurality of signal samples with at least one symbol and with interference effects between different symbols. The receiver also comprises suppression circuitry, for suppressing the interference effects. The receiver also comprises circuitry for receiving signals from the suppression circuitry and for providing estimates of a group of bits. The receiver also comprises error detection circuitry for detecting an error in a packet that comprises the group of bits. Lastly, the receiver also comprises circuitry for requesting the transmitter to transmit a retransmission of a packet in response to detecting the error.

Abstract: Systems and methods for application profiles and device classes in power line communications (PLCs) are described. In some embodiments, a PLC device has the device class defined by a PHY layer and may include a processor and a memory coupled to the processor. The memory may be configured to store program instructions, which may be executable by the processor to cause the PLC device to communicate with a higher-level PLC apparatus over a power line using a frequency band. The frequency band may be selected based upon an application profile and/or a device class associated with the PLC device. In some implementations, the higher-level PLC apparatus may include a PLC gateway or a data concentrator, and the PLC device may include a PLC modem or the like. Examples of application profiles include access communications, in-premises connectivity, AC charging, and/or DC charging. Device classes may represent a minimum communication data rate and/or an operating frequency band restriction of the PLC device.

Abstract: A method of operating a transmitter (FIGS. 3A and 5A) is disclosed. The method includes receiving a sequence of data bits (DATA), wherein each data bit has a respective sequence number. A first data bit of the sequence is spread (508) with a first spreading code (504) determined by the sequence number (502) of the first data bit. A second data bit of the sequence is spread (508) with an inverse of the first spreading code (506) determined by the sequence number (502) of the second data bit. The first and second data bits are modulated (510) and transmitted (516) to a remote receiver.

Abstract: Systems for channel selection in power line communications (PLC) are described. In some embodiments, a PLC device may include a processor and a memory. The memory stores instructions executable by the processor to cause the PLC device perform operations. One or more time slots in each of a plurality of frequency bands are sequentially scanned. A packet transmitted by a second PLC device to the PLC device over one of the plurality of frequency bands is detected. Additional packets received from the second PLC device are synchronized across the plurality of frequency bands based, at least in part, upon the detected packet. The additional packets are organized in a plurality of frames. Each of the plurality of frames having been transmitted by the second PLC device to the PLC device over a respective one of the plurality of frequency bands. Each frame has a plurality of time slots, and each time slot has a pair of beacon and bandscan packets.

Abstract: Systems and methods for enhanced carrier sense multiple access (CSMA) protocols are described. In various implementations, these systems and methods may be applicable to Power Line Communications (PLC). For example, a method may include attempting to access a communications channel to transmit a frame after a backoff time proportional to a randomly generated number within a contention window (CW), the CW having an initial value carried over from a previous transmission of a different frame. Additionally or alternatively, some of techniques described herein may facilitate the spreading of the time over which devices attempt to transmit packets, thereby reducing the probability of collisions using, for example, Additive Decrease Multiplicative Increase (ADMI) mechanisms.

Abstract: Embodiments of the present disclosure provide a transmitter, a receiver and methods of operating a transmitter or a receiver. In one embodiment, the transmitter is for use with a base station and includes a primary module configured to provide a primary synchronization signal. The transmitter also includes a secondary mapping module configured to provide a secondary synchronization signal derived from two sequences taken from a same set of N sequences and indexed by an index pair (S1, S2) with S1 and S2 ranging from zero to N?1, wherein the index pair (S1, S2) is contained in a mapped set of index pairs corresponding to the same set of N sequences that defines a cell identity group. Additionally, the transmitter further includes a transmit module configured to transmit the primary and secondary synchronization signals.

Abstract: A method of communications includes compiling a data frame for physical layer (PHY) by a first communications device at a first communications node on a network. The data frame includes a single tone PHY header portion and a data payload portion in a set of tones including at least one tone having a frequency different from a frequency of the single tone. The PHY header portion includes tone mask identification information identifying the set of tones. The first communications device transmits the data frame over the powerline to a second communications device at a second communications node on the powerline. The second communications device receives the data frame, and decodes the data payload using the tone mask identification information in the PHY header portion.

Abstract: A probe, listen and select (PLS) technique can be used to select from an available frequency spectrum a frequency band whose communication quality is suitable for wireless communication at a desired rate. Probe packets can be transmitted on different frequencies (223) during a known period of time (TPLS), and frequency channel quality information can be obtained (225) from the probe packets. This quality information can then be used to select a desirable frequency band (227). The communication quality of the selected band can also be used as basis for selecting (141) from among a plurality of modulation and coding combinations that are available for use in communications operations.

Abstract: Systems and methods for designing, using, and/or implementing media access control (MAC) protocols with subbanding are described. In some embodiments, a method may include receiving a beacon packet during one of a plurality of beacon slots of a superframe, each beacon slot corresponding to one of a plurality of different downlink subbands. The method may also include identifying, based on the received beacon packet, contention access periods following the beacon slots, each of the contention access periods corresponding to one of a plurality of different uplink subbands. The method may further include transmitting an information packet over each of the plurality of uplink subbands during the contention access periods. Then, the method may include receiving, during a guaranteed time slot following the contention access periods, an indication of a selected one of the plurality of uplink subbands to be used in a subsequent communications.

Abstract: Systems and methods for application profiles and device classes in power line communications (PLCs) are described. In some embodiments, a PLC device may include a processor and a memory coupled to the processor. The memory may be configured to store program instructions, which may be executable by the processor to cause the PLC device to communicate with a higher-level PLC apparatus over a power line using a frequency band. The frequency band may be selected based upon an application profile and/or a device class associated with the PLC device. In some implementations, the higher-level PLC apparatus may include a PLC gateway or a data concentrator, and the PLC device may include a PLC modem or the like. Examples of application profiles include access communications, in-premises connectivity, AC charging, and/or DC charging. Device classes may represent a minimum communication data rate and/or an operating frequency band restriction of the PLC device.

Abstract: Systems and methods for channel selection in power line communications (PLC) are described. In some embodiments, a method may include defining a plurality of frames, each frame having a plurality of time slots. The method may also include assembling a pair of beacon and bandscan packets within each of time slot of each frame. The method may further include sequentially transmitting each of the frames over a corresponding one of a plurality of different frequency bands. In some implementations, each bandscan packet may include a slot index indicating a position of its time slot within its respective frame and/or a band index indicating one of the plurality of different frequency bands. In response to having transmitted the plurality of frames, the method may include receiving one or more packets indicating a selection of one or more of the plurality of different frequency bands to be used in subsequent communications.

Abstract: Systems and methods for designing, using, and/or implementing hybrid communication networks are described. In various embodiments, these systems and methods may be applicable to power line communications (PLC). For example, one or more of the techniques disclosed herein may include methods to coordinate medium-to-low voltage (MV-LV) and low-to-low voltage (LV-LV) PLC networks when the MV-LV network operates in a frequency subband mode and the LV-LV network operates in wideband mode (i.e., hybrid communications). In some cases, MV routers and LV routers may have different profiles. For instance, MV-LV communications may be performed using MAC superframe structures, and first-level LV to lower-level LV communications may take place using a beacon mode. Lower layer LV nodes may communicate using non-beacon modes. Also, initial scanning procedures may encourage first-to-second-level LV device communications rather than MV-to-first-level LV connections.

Abstract: A physical layer (PHY) data frame for use in conjunction with processor in a node, processor coupled to a program memory for storing a sequence of operating instructions. The frame has a preamble, PHY header, a MAC header and a MAC payload. The PHY header includes a destination address field having a destination address therein. The destination address is used by the processor to determine match with the node address.

Abstract: A method of powerline communications in a powerline communications (PLC) network including a first PLC device and at least a second PLC device. The first PLC device transmits a data frame to the second node over a PLC channel. The second PLC device has a data buffer for storing received information. The second PLC device runs a flow control algorithm which determines a current congestion condition or a projected congestion condition of the data buffer based on at least one congestion parameter. The current congestion condition and projected congestion condition include nearly congested and fully congested. When the current or projected congestion condition is either nearly congested or fully congested, the second PLC device transmits a BUSY including frame over the PLC channel to at least the first PLC device. The first PLC device defers transmitting of any frames to the second PLC device for a congestion clearing wait time.

Abstract: Systems and methods for designing, using, and/or implementing non-beacon network communications using frequency subbands are described. In various implementations, these systems and methods may be applicable to Power Line Communications (PLC). For example, a method may include transmitting a beacon request message over a given one of a plurality of frequency subbands, receiving a plurality of beacons in response to having transmitted the beacon request message, each of the plurality of beacons received over a respective one of the plurality of frequency subbands, and calculating a downlink quality report based, at least in part, upon the received beacons. The method may also include transmitting the downlink quality report over each of the plurality of frequency subbands and receiving a subband allocation command in response to having transmitted the downlink quality report, the subband allocation command indicating a downlink subband assignment and an uplink subband assignment.

Abstract: A method of powerline communications including a first node and at least a second node on a powerline communications (PLC) channel in a PLC network. The first node sends a physical layer (PHY) data frame on the PLC channel including a preamble, a PHY header, a MAC header and a MAC payload. The MAC header includes a Cyclic Redundancy Check (CRC) field (MH-CRC field). The second node receives the data frame, parses the MAC header to reach the MH-CRC field, and performs CRC verification using the MH-CRC field to verify the MAC header. If the CRC verification is successful, (i) the second node parses another portion of the MAC header to identify a destination address of the data frame and (ii) to determine whether the data frame is intended for the second node from the destination address.