Abstract: A method including generating a matrix. The matrix includes first and second portions. The first portion includes data bits. The second portion includes parity bits and has a triple diagonal structure. The triple diagonal structure includes a first central diagonal, a second central diagonal, and a last row diagonal. Bits of the first central diagonal, the second central diagonal, and the last row diagonal are equal to 1 and a remainder of bits in the triple diagonal structure are equal to 0. The method further includes: determining parity bits based on the matrix; if the matrix is generated to codify data for transmission from a first device to a second device, transmitting the parity bits from the first device to the second device; and if the matrix is generated based on a vector of bits received from the second device, generating a block of data based on the parity bits.

Abstract: A system including a coupler to couple a signal to a plurality of conductors of an electric network and a transmitter to select a plurality of modes to inject the signal into the plurality of conductors and to transmit the signal via the plurality of conductors. The plurality of modes is selected from a group consisting of a first mode, a second mode, and a third mode. The first mode includes injection of the signal through a selective combination of the plurality of conductors and circulation of current through ground. The second mode includes injection of the signal through a first conductor and return through a second conductor. The third mode includes injection of the signal through one or more first conductors and return through one or more second conductors. The first conductors are different than the second conductors.

Abstract: A method including generating a matrix. The matrix includes first and second portions. The first portion includes data bits. The second portion includes parity bits and has a triple diagonal structure. The triple diagonal structure includes a first central diagonal, a second central diagonal, and a last row diagonal. Bits of the first central diagonal, the second central diagonal, and the last row diagonal are equal to 1 and a remainder of bits in the triple diagonal structure are equal to 0. The method further includes: determining parity bits based on the matrix; if the matrix is generated to codify data for transmission from a first device to a second device, transmitting the parity bits from the first device to the second device; and if the matrix is generated based on a vector of bits received from the second device, generating a block of data based on the parity bits.

Abstract: A system for determining a frequency error of an orthogonal frequency division multiplexing (OFDM) signal having a first frequency. The system includes a plurality of filters configured to output a plurality of second signals, each of the plurality of second signals corresponding to a respective one of a plurality of different frequency bands of the OFDM signal. Each of the plurality of second signals includes a corresponding synchronization symbol associated with the OFDM signal. A Fourier transform circuit is configured to receive the plurality of second signals from each of the plurality of filters and output the plurality of second signals. The system is configured to determine the frequency error of the OFDM signal based on the synchronization symbols of the plurality of second signals.

Abstract: A method including receiving power, from a power line, at a device configured to communicate via the power line. The power from the power line is received at the device via a power cord of the device being connected, via a connector, to a power outlet from which the power of the power line is supplied. The connector is coupled to a first end of the power cord. The device is coupled to a second end of the power cord. The method further includes supplying a signal generated by the device to a choke located on the power cord. The choke is located closer to the first end of the power cord than to the second end of the power cord. The method further includes transmitting the signal from the choke to the power line for communication via the power line.

Abstract: A signal repeater includes a port, an amplifier, and an adaptive device. The port is configured to connect to an electrical line of an electrical grid between devices. Communication over the electrical line and between the devices includes transmission of a first signal. The port is configured to receive the first signal from the electrical line. An amplifier is configured to receive a second signal based on the first signal, and amplify the second signal. The port is configured to receive the amplified second signal, and provide the amplified second signal to the electrical line. An adaptive device is configured to, based on the first signal, adjust an output impedance of the signal repeater to match a first impedance of a load on the signal repeater. The first impedance is seen by the signal repeater at the port, and wherein the first impedance includes an impedance of the electrical line.

Abstract: A system including a first network device, a second network device, and a third network device. The first network device is configured to transmit a first starting signal. The second network device configured to transmit a second starting signal, wherein at least one of the first network device and the second network device is further configured to change a ratio between at least one of respective phases of carriers of the first starting signal and the second starting signal and respective amplitudes of the carriers of the first starting signal and the second starting signal. The third network device is configured to receive the first starting signal and the second starting signal, selectively allow communication with the first network device based on the ratio, and ignore communication from the second network device based on the ratio.

Abstract: An electrical device includes signal ports, transformers, and a differential mode device. The transformers are in communication with the signal ports, respectively. The transformers are configured to receive input signals, respectively, from the signal ports. Each transformer is configured to inject the respective input signal onto a pair of output lines of the transformer. The differential mode device is connected to a first output line of the pair of output lines of a first transformer exclusive of connection to a second output line of the first transformer. The differential mode device is configured to inject a signal from the first output line onto the pair of output lines of a second transformer. Signals from the pair of output lines of the second transformer are injected onto a pair of conductors, respectively, of a communications medium.

Abstract: A transceiver includes a transmitter and a receiver. The transmitter receives a first orthogonal frequency division multiplexing (OFDM) signal, and generates a first analog signal based on the first OFDM signal. The first OFDM signal has a first bandwidth, a first spectral position, and a first frequency spectrum. The first frequency spectrum of the first OFDM signal has a first set of frequencies with first amplitudes. The receiver receives a second analog signal, and generates a second OFDM signal based on the second analog signal. The second OFDM signal has a second bandwidth, a second spectral position, and a second frequency spectrum. The second frequency spectrum of the second OFDM signal has a second set of frequencies with second amplitudes. The transmitter varies the first bandwidth, the first spectral position, and the first amplitudes independent of the second bandwidth, the second spectral position, and the second amplitudes.

Abstract: A device is configured to inject signals onto a medium made up of conductors and a reference plane. Transformers inject the signals onto the conductors by orthogonal modes. Differential mode chokes each include one input and two outputs. The input is connected to one end of a secondary winding of one of the transformers, or one of the outputs of another one of the chokes. The two outputs are connected to either the inputs of two others of the chokes, the input of another one of the chokes and a conditioner of one of the conductors, or conditioners of two of the conductors. The number of chokes depends on a number of non-differential modes used. The injections that use the chokes are injections selected from between pseudo-differential injections, injection in common mode, or a combination of pseudo-differential injections and injection in common mode.

Abstract: A system including a coupler to couple a signal to a plurality of conductors of an electric network and a transmitter to select a plurality of modes to inject the signal into the plurality of conductors and to transmit the signal via the plurality of conductors. The plurality of modes is selected from a group consisting of a first mode, a second mode, and a third mode. The first mode includes injection of the signal through a selective combination of the plurality of conductors and circulation of current through ground. The second mode includes injection of the signal through a first conductor and return through a second conductor. The third mode includes injection of the signal through one or more first conductors and return through one or more second conductors. The first conductors are different than the second conductors.

Abstract: A transmission medium includes inductive couplers, signal lines and conductors. Each of the signal lines is configured to receive a respective one of multiple input signals. Each of the signal lines extends through at least one of the inductive couplers and is configured to inductively transmit one of the input signals to the at least one of the inductive couplers. Each of the conductors is configured to extend through at least two of the inductive couplers. The conductors include a first conductor and a second conductor. The inductive couplers are configured to inductively transmit the input signals to the conductors to generate a first current and a second current. The first current flows in the first conductor and towards an output of the first conductor. The second current flows in the second conductor and towards an input of the second conductor.

Abstract: Method for increasing the performance of a communications system on a medium formed by multiple conductors which increases the performance of a communications system by means of the creation of numerous communication channels with a high degree of isolation between each other on the same physical medium formed by multiple conductors. The method can be extended to be used in various applications, such as the reuse of frequencies on the same channel, the increase of the capacity of the point-to-point links in a network and the improvement of performance and reliability when used with digital processing of signals for transmission or reception, among others.

Abstract: A system including a first network device, a second network device, and a third network device. The first network device is configured to transmit a first starting signal. The second network device configured to transmit a second starting signal, wherein at least one of the first network device and the second network device is further configured to change a ratio between at least one of respective phases of carriers of the first starting signal and the second starting signal and respective amplitudes of the carriers of the first starting signal and the second starting signal. The third network device is configured to receive the first starting signal and the second starting signal, selectively allow communication with the first network device based on the ratio, and ignore communication from the second network device based on the ratio.

Abstract: A signal repeater includes a port, an amplifier, and an adaptive device. The port is configured to connect to an electrical line of an electrical grid between devices. Communication over the electrical line and between the devices includes transmission of a first signal. The port is configured to receive the first signal from the electrical line. An amplifier is configured to receive a second signal based on the first signal, and amplify the second signal. The port is configured to receive the amplified second signal, and provide the amplified second signal to the electrical line. An adaptive device is configured to, based on the first signal, adjust an output impedance of the signal repeater to match a first impedance of a load on the signal repeater. The first impedance is seen by the signal repeater at the port, and wherein the first impedance includes an impedance of the electrical line.

Abstract: A system for determining a frequency error of an orthogonal frequency division multiplexing (OFDM) signal having a first frequency. The system includes a plurality of filters configured to output a plurality of second signals, each of the plurality of second signals corresponding to a respective one of a plurality of different frequency bands of the OFDM signal. Each of the plurality of second signals includes a corresponding synchronization symbol associated with the OFDM signal. A Fourier transform circuit is configured to receive the plurality of second signals from each of the plurality of filters and output the plurality of second signals. The system is configured to determine the frequency error of the OFDM signal based on the synchronization symbols of the plurality of second signals.

Abstract: A method including receiving power, from a power line, at a device configured to communicate via the power line. The power from the power line is received at the device via a power cord of the device being connected, via a connector, to a power outlet from which the power of the power line is supplied. The connector is coupled to a first end of the power cord. The device is coupled to a second end of the power cord. The method further includes supplying a signal generated by the device to a choke located on the power cord. The choke is located closer to the first end of the power cord than to the second end of the power cord. The method further includes transmitting the signal from the choke to the power line for communication via the power line.

Abstract: A method for simultaneous transmission in time and frequency of multiple communications of data using orthogonal frequency division multiplexing (OFDM) modulation includes transmitting the multiple communications of data at a same time on a single channel. A first starting signal, transmitted using a first network device, and a second starting signal, transmitted using a second network device, are used in transmission of a frame. Properties of the first starting signal and the second starting signal for transmission of each of the multiple communications are modified by shifting a frequency of the first starting signal with respect to a frequency of the second starting signal so that remaining communications coincident in time and frequency with respect to a given communication are ignored. The frequency of the first starting signal is shifted an amount equal to a fraction of a separation between carriers of the OFDM modulation.

Abstract: The invention relates to a single-port signal repeater. The repeater is connected in parallel to the communication means (3), on which only one access point (5) is needed. The repeater (4) comprises an amplifier, a hybrid circuit and a feedback and increases the range and transmission capacity for communications made on a conducted medium without the drawbacks of traditional repeaters, which have to interrupt the line and need two access points to the channel.

Abstract: A system for synchronization of an orthogonal frequency division multiplexing signal having a first frequency. The system includes filters configured to receive the OFDM signal, and output second signals corresponding to different frequency bands of the OFDM signal. Each of the second signals includes a corresponding synchronization symbol associated with the OFDM signal, and the synchronization symbols of each of the second signals are the same. The system further includes a Fourier transform circuit configured to receive the second signals from the filters, and output the second signals. Each of the second signals has a second frequency. The system is configured to detect the synchronization symbols in the second signals, and detect a start of OFDM symbols in the OFDM signal based on the detected synchronization symbols. The start of the OFDM symbols corresponds to an average of a plurality of estimations of the start of the OFDM symbols.