Disclosed are a method and a device for supplying electrical power for two or more technical systems, which are connected to an electrical supply line with a feed point, arranged in a connecting rod, and for data transmission between the feed point and the technical systems, supplying power to the technical systems is done with essentially constant current intensity. Data transmission from the feed point to the technical systems is done by modulating the current intensity, and data transmission from the technical systems to the feed point is done by modulating the voltage.

A component of an HVAC system includes a controller; a communications module in communication with the controller, the communications module including: a modulator/demodulator configured to encode and decode data in a modulated waveform on a communications interface.

Embodiments of methods and systems for supporting coexistence of multiple technologies in a Power Line Communication (PLC) network are disclosed. A long coexistence preamble sequence may be transmitted by a device that has been forced to back off the PLC channel multiple times. The long coexistence sequence provides a way for the device to request channel access from devices on the channel using other technology. The device may transmit a data packet after transmitting the long coexistence preamble sequence. A network duty cycle time may also be defined as a maximum allowed duration for nodes of the same network to access the channel. When the network duty cycle time occurs, all nodes will back off the channel for a duty cycle extended inter frame space before transmitting again. The long coexistence preamble sequence and the network duty cycle time may be used together.

The present invention provides an FM Orthogonal Frequency Division Multiplexing (OFDM) modulation process that enable high-speed data communications over any transmission media and networks. The process is implemented with a modem device modulator and demodulator that provides communication with several other modem devices along any communication media that uses an FM OFDM modulation technique, a physical transmission medium such as power lines, or wireless (air), or cable, or twisted pairs communication media.

A power line communication device includes a DC power source device, a power line, and a master station that modulates a supply voltage VBUS supplied to the power line according to transmission data to be transmitted. The master station includes a modulation capacitor that is precharged with a modulation amplitude voltage, a polarity switch unit that determines a polarity of the modulation capacitor connected to the power line according to transmission data, and an inductor connected between the DC power source device and the power line.

A system includes an AC power module structured to provide alternating current (AC) electrical power; a power distribution wiring harness structured to receive the AC electrical power from the AC power module; a plurality of inductive coupling modules coupled to the power distribution wiring harness, and configured to transmit the AC electrical power to at least one load; and, a signal injection module structured to inject a communication signal on the power distribution wiring harness using signal modulation during a transient moment of operation corresponding to a low electrical noise operating range of electromagnetic interference generated by components of a vehicle.

Embodiments of the invention provide multiple cyclic prefix lengths for either both the data-payload and frame control header or only the data payload. Frame control header (FCH) and data symbols have an associated cyclic prefix. A table is transmitted in the FCH symbols, which includes a cyclic prefix field to identify the cyclic prefix length used in the data payload. A receiver may know the cyclic prefix length used in the FCH symbols in one embodiment. In other embodiments, the receiver does not know the FCH cyclic prefix length and, therefore, attempts to decode the FCH symbols using different possible cyclic prefix lengths until the FCH symbols are successfully decoded.

A welding system is provided. The welding system includes a low power transceiver configured to be coupled to a weld cable. The low power transceiver includes a low power transmitter, a low power receiver, and a first processor. The low power receiver is configured to transmit one or more unmodulated tones through the weld cable to a welding power supply. The low power receiver is configured to receive the one or more unmodulated tones through the weld cable from the welding power supply. The first processor is configured to determine one or more channel equalization filter coefficients related to the weld cable corresponding to a distortive characteristic of the weld cable.

A power line communication device includes a DC power source device, a power line, and a master station that modulates a supply voltage VBUS supplied to the power line according to transmission data to be transmitted. The master station includes a modulation capacitor that is precharged with a modulation amplitude voltage, a polarity switch unit that determines a polarity of the modulation capacitor connected to the power line according to transmission data, and an inductor connected between the DC power source device and the power line.

An example method for performing a time synchronization among a plurality of electronic components within a bottom hole assembly (BHA) includes modifying a preamble of a digital signal by adding symbols to the preamble of the digital signal to mark a moment in time. The method further includes generating a physical waveform that includes the modified preamble and transmitting the physical waveform over a powerline, using a powerline interface, to other of the plurality of electronic components. The method further includes transmitting an absolute time value to the other of the other of the plurality of electronic components. The method further includes performing, by at least one of the other of the plurality of electronic components, the time synchronization by detecting the physical waveform, determining a local time drift compared to the moment in time and the absolute time value, and adjusting a local clock to the absolute time value.