Abstract: A network device may transmit a short packet when the length of application data that will be transmitted does not exceed a threshold length. In some embodiments, the network device may transmit the application data in a frame control field of the short packet. The short packet may not include a payload field.

Abstract: A network device may transmit a short packet when the length of application data that will be transmitted does not exceed a threshold length. In some embodiments, the network device may transmit the application data in a frame control field of the short packet. The short packet may not include a payload field. In other embodiments, the network device may support multiple short payload field lengths and may transmit the application data in a short payload field with an appropriate short payload field length. The network device may also support communication techniques to transmit the application data in the short packet.

Abstract: A method for determining transmission properties of a multiple-input multiple-output (MIMO) channel. In one embodiment, a MIMO receiver receives a non-beamformed, spatial-multiplexed (SM) sounding signal over multiple signal paths of the MIMO channel. The receiver determines beamforming information including beamforming coefficients and beamforming Eigenvalues for the MIMO channel based, at least in part, on frequency responses of the signal paths. The receiver determines a first signal-to-noise ratio (SNR) estimate for one or more SM data streams of the SM sounding signal based, at least in part, on the determined beamforming information.

Abstract: A first communication device can dynamically select a mode of communication (such as a MIMO mode or a SISO mode) to improve throughput. In selecting the communication mode, the first communication device may determine whether a powerline medium effectively supports multi-channel communication. Even when the first communication device and a second communication device both are capable of using a MIMO mode, the first communication device may select a SISO mode if it determines that one of the channels is ill-conditioned for communication. For example, the powerline medium may be affected by a missing conductor, protective circuit, or other attenuation that impairs the second channel differently than the first channel. If the disparity between the first channel and the second channel is greater than a threshold, the first communication device may switch to a SISO mode to improve performance.

Abstract: A network device may be configured to iteratively modify an initial tone map for each communication region of a powerline cycle to minimize the time before application data can be transmitted. A first network device estimates an initial tone map for each communication region based, at least in part, on sounding messages received from a second network device. The first network device determines whether to estimate a modified tone map for the first communication region based on at least one performance measurement associated with a data packet generated using the initial tone map for the first communication region. If so, the second network device retransmits the sounding messages in the first communication region that will be used to modify the initial tone map for the first communication region, and the second network device continues to transmit the data packets using the initial tone maps in the remaining communication regions.

Abstract: A first communication device can dynamically select a mode of communication (such as a MIMO mode or a SISO mode) to improve throughput. In selecting the communication mode, the first communication device may determine whether a powerline medium effectively supports multi-channel communication. Even when the first communication device and a second communication device both are capable of using a MIMO mode, the first communication device may select a SISO mode if it determines that one of the channels is ill-conditioned for communication. For example, the powerline medium may be affected by a missing conductor, protective circuit, or other attenuation that impairs the second channel differently than the first channel. If the disparity between the first channel and the second channel is greater than a threshold, the first communication device may switch to a SISO mode to improve performance.

Abstract: A response interframe space (RIFS) time period may be adapted in a communication system. The RIFS time period may be determined based, at least in part, on a processing time used by a receiving device to process a received physical layer transmission from a transmitting device. The RIFS may be optimized in consideration of channel conditions for a particular communications channel, capabilities of a receiving device, and/or characteristics of a particular physical layer transmission. For example, the RIFS may be dependent on characteristics of a final transmission symbol used to transmit a physical layer transmission. The RIFS may depend on a processing time associated with decoding forward error correction (FEC) encoded blocks that end in the final transmission symbol. The RIFS may depend on a quantity of decoding iterations in a communication system that uses iterative decoding of FEC encoded blocks.

Abstract: A network device may be configured to adapt beamforming parameters for a communication region of a powerline cycle in response to variations in communication channel conditions. A first network device can estimate initial beamforming parameters for each communication region based on sounding messages received from a second network device. The first network device can determine coarse beamforming parameters for each communication region based on data packets received from the second network device using the initial beamforming parameters. The first network device can determine a difference parameter for the first communication region based, at least in part, on a first initial beamforming parameter associated with the first communication region and a first coarse beamforming parameter associated with the first communication region.

Abstract: A response interframe space (RIFS) time period may be adapted in a communication system. The RIFS time period may be determined based, at least in part, on a processing time used by a receiving device to process a received physical layer transmission from a transmitting device. The RIFS may be optimized in consideration of channel conditions for a particular communications channel, capabilities of a receiving device, and/or characteristics of a particular physical layer transmission. For example, the RIFS may be dependent on characteristics of a final transmission symbol used to transmit a physical layer transmission. The RIFS may depend on a processing time associated with decoding forward error correction (FEC) encoded blocks that end in the final transmission symbol. The RIFS may depend on a quantity of decoding iterations in a communication system that uses iterative decoding of FEC encoded blocks.

Abstract: A network device may be configured to adapt beamforming parameters for a communication region of a powerline cycle in response to variations in communication channel conditions. A first network device can estimate initial beamforming parameters for each communication region based on sounding messages received from a second network device. The first network device can determine coarse beamforming parameters for each communication region based on data packets received from the second network device using the initial beamforming parameters. The first network device can determine a difference parameter for the first communication region based, at least in part, on a first initial beamforming parameter associated with the first communication region and a first coarse beamforming parameter associated with the first communication region.

Abstract: A network device may be configured to iteratively modify an initial tone map for each communication region of a powerline cycle to minimize the time before application data can be transmitted. A first network device estimates an initial tone map for each communication region based, at least in part, on sounding messages received from a second network device. The first network device determines whether to estimate a modified tone map for the first communication region based on at least one performance measurement associated with a data packet generated using the initial tone map for the first communication region. If so, the second network device retransmits the sounding messages in the first communication region that will be used to modify the initial tone map for the first communication region, and the second network device continues to transmit the data packets using the initial tone maps in the remaining communication regions.

Abstract: A receiving station receives an orthogonal frequency division multiplexing (OFDM) symbol via a shared medium, the OFDM symbol comprising a first set of frequency components modulated with preamble information and a second set of frequency components modulated with information. The receiving station processes sampled values of the received OFDM symbol based on channel characteristics estimated from the first set of frequency components to decode information encoded on a first subset of the second set of frequency components. The receiving station processes sampled values from the first symbol based on channel characteristics estimated from the first set of frequency components and the first subset of the second set of frequency components to decode information encoded on a second subset of the second set of frequency components.

Abstract: A network device may transmit a short packet when the length of application data that will be transmitted does not exceed a threshold length. In some embodiments, the network device may transmit the application data in a frame control field of the short packet. The short packet may not include a payload field. In other embodiments, the network device may support multiple short payload field lengths and may transmit the application data in a short payload field with an appropriate short payload field length. The network device may also support communication techniques to transmit the application data in the short packet.

Abstract: An asymmetric mixed-mode transceiver may determine to communicate with a destination powerline communication device. The asymmetric mixed-mode transceiver may determine whether an operational mode associated with the destination powerline communication device is a multiple-output multiple-input (MIMO) mode or a single-output single-input (SISO) mode. The asymmetric mixed-mode transceiver may dynamically change its operational mode to either the MIMO mode or the SISO mode to match the operational mode of the destination powerline communication device. The asymmetric mixed-mode transceiver may receive a communication from a source powerline communication device. The asymmetric mixed-mode transceiver may determine whether an operational mode associated with the source powerline communication device is the MIMO mode or the SISO mode. The asymmetric mixed-mode transceiver may dynamically change its operational mode to match the operational mode of the source powerline communication device.

Abstract: A system and method for communicating information through a powerline medium including at least three conductors, where the transmitter transmits at least two signals onto the powerline medium and the receiver receives one or more signals from the powerline medium. The transmitter adjusts the power transmitted into the powerline medium in order to set the adjusted transmit power to a predetermined level, e.g., a level that ensures power radiated from the powerline medium does not exceed a regulatory limit. The process of adjusting the transmit power may take into account a functional relationship between the transmitted power and properties of the channel.

Abstract: A receiving station receives a waveform that includes at least a first symbol of a predetermined symbol length and comprising a first set of frequency components at predetermined carrier frequencies modulated with preamble information and a second set of frequency components at predetermined carrier frequencies modulated with information. The receiving station processes sampled values from the first symbol based on channel characteristics estimated from the first set of frequency components to decode information encoded on a first subset of the second set of frequency components. The receiving station processes sampled values from the first symbol based on channel characteristics estimated from the first set of frequency components and the first subset of the second set of frequency components to decode information encoded on a second subset of the second set of frequency components.

Abstract: A method for transmitting information in a multi-carrier system includes: identifying a first set of carrier signals, associated with a first code rate; and identifying a second set of carrier signals, associated with a second code rate. The method also includes partitioning a first sequence of bits representing a single symbol into a first group of bits associated with the first code rate and at least a second group of bits associated with the second code rate; interleaving a subset of bits from the first group to map multiple bits from the first group to respective carrier signals in the first set of carrier signals to achieve the first code rate; and interleaving a subset of bits from the second group to map multiple bits from the second group to respective carrier signals in the second set of carrier signals to achieve the second code rate.

Abstract: A system and method for communicating information through a powerline medium including at least three conductors, where the transmitter transmits at least two signals onto the powerline medium and the receiver receives one or more signals from the powerline medium. The transmitter adjusts the power transmitted into the powerline medium in order to set the adjusted transmit power to a predetermined level, e.g., a level that ensures power radiated from the powerline medium does not exceed a regulatory limit. The process of adjusting the transmit power may take into account a functional relationship between the transmitted power and properties of the channel.

Abstract: Transmitting information between stations in a network includes: modulating first main information and auxiliary information onto a first portion of a signal according to a predetermined constellation having multiple regions and the same sub-constellation within each region having multiple points, with the first main information being modulated using a first selected region of the constellation, and the auxiliary information being modulated using a first selected point of the sub-constellation within the first selected region; modulating second main information and a copy of the auxiliary information onto a second portion of the signal according to the constellation, with the second main information being modulated using a second selected region of the constellation, and the copy of the auxiliary information being modulated using a second selected point of the sub-constellation within the second selected region, where the second selected point occurs at a different portion of the sub-constellation than the fi

Abstract: A receiving station receives an orthogonal frequency division multiplexing (OFDM) symbol via a shared medium, the OFDM symbol comprising a first set of frequency components modulated with preamble information and a second set of frequency components modulated with information. The receiving station processes sampled values of the received OFDM symbol based on channel characteristics estimated from the first set of frequency components to decode information encoded on a first subset of the second set of frequency components. The receiving station processes sampled values from the first symbol based on channel characteristics estimated from the first set of frequency components and the first subset of the second set of frequency components to decode information encoded on a second subset of the second set of frequency components.