摘要:
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.
摘要:
Systems and methods for building, transmitting, and receiving robust protocol data units (PDUs) in power line communications (PLC) are described. In some embodiments, a method may include receiving a PDU, applying bit-level repetition to at least a portion of the PDU to create a repeated portion, block interleaving two or more symbols corresponding to the repeated portion to create a block interleaved portion, inserting pilot tones in the block interleaved portion, and modulating each tone in the block interleaved portion with respect to a nearest one of the inserted pilot tones to create a robust PDU. In some implementations, the robust PDU may include a first header portion carrying information encoded using a first version of a PLC protocol (e.g., a legacy standard) and a second header portion carrying information encoded using a second version of the PLC protocol (e.g., a newer version of the same standard).
摘要:
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.
摘要:
Systems and methods for implementing power line communications (PLC) across different voltage domains using multiple frequency subbands are described. From an end node's perspective (e.g., a PLC device), a method may include scanning a plurality of downlink subbands usable by a base node (e.g., a PLC router, etc.) to communicate with one or more PLC devices (e.g., other end nodes) from a medium voltage (MV) to a low voltage (LV) power line, and transmitting association request(s) to the base node that select and/or allow the base node to select one or more downlink subbands for use in subsequent communications. From the base node's perspective, the method may include selecting one or more of a plurality of uplink subbands for use in subsequent communications based on the received association request(s). In various implementations, the selection of downlink and/or uplink subbands may be based on signal-to-noise ratio (SNR) values and/or congestion indicators.
摘要:
Communication devices, such as base nodes and modems, that comply with two or more different standards operate on a shared communication channel. To avoid mutual interference, a base node operating under a first standard reserves time using a contention free period designation. The base node allows devices operating under a second standard to communicate during the reserved time by not assigning the contention free period to another device operating under the first standard. Alternatively, a device using the first standard may avoid interference from transmissions generated under the second standard by modifying data packets prior to transmission. A prefix corresponding to a preamble in the second standard is added to the beginning of the data packet created under the first standard. Devices operating under the second standard observe the prefix and recognize that the channel is active. The second-standard devices backoff from transmission thereby minimizing interference.
摘要:
Systems and methods for power line transmission are disclosed in which transmitters and receivers are connected to one or more phases of the power line. At least one symbol stream to be transmitted on the power line network is generated. The at least one symbol stream is scaled using a weight vector to generate a plurality of scaled symbol streams. The weight vector comprises a plurality of weights, each corresponding to a phase of the power line network. Each of the scaled symbol streams are transmitted on a corresponding phase of the power line network. A zero crossing detector identifies phase information for a receiver. A concentrator adapts signals to be sent to the receiver based upon the phase associated with the receiver.
摘要:
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.
摘要:
A coordinated multipoint transmitter is for use with a network MIMO super-cell and includes a coordination unit configured to provide joint link processing to coordinate a multipoint transmission corresponding to a set of transmission points. Additionally, the coordinated multipoint transmitter also includes a transmission unit configured to transmit the multipoint transmission using the set of transmission points. Additionally, a coordinated transmission receiver is for use with a network MIMO super-cell and includes a reception unit configured to receive a multipoint transmission corresponding to a set of transmission points. The coordinated transmission receiver also includes a processing unit configured to process the multipoint transmission from the set of transmission points.
摘要:
Coupling and interface circuits for powerline modems are disclosed. A powerline modem may be coupled to a low voltage (LV) line or a medium voltage (MV) line using a circuit that is designed to compensate for signal attenuation and loss that is created by the a LV/MV transformer and/or a MV coupler. In one embodiment, separate coupling transformers may be used by the modem for reception and transmission. In other embodiments, a capacitance is switched on the transmission line before the modem transmits to lower the line impedance.
摘要:
Embodiments provide a method for determining the number of parity bytes that are added by a Reed-Solomon encoder. The number of parity bytes are equivalent to the error correcting capability of the Reed-Solomon code. The number of parity bytes is based on the payload length or the information block size used in the Reed-Solomon encoder. Other factors may also be used to make this choice.