A lighting system includes a light-emitting diode (LED) that emits light having a hue that varies in response to variations in a voltage applied to the LED and an intensity that varies in response to variations in a duty cycle of the applied voltage. The lighting system includes a controller configured to receive a command signal having a periodic peak voltage and a periodic valley voltage. The controller includes a peak detector and a valley detector that detects the peak voltage and the valley voltage, respectively. The controller includes a pulse generator that generates a pulse stream having a pulse-voltage magnitude substantially equal to the detected peak voltage and a pulse-voltage duty cycle substantially equal to the ratio of the detected valley voltage to the detected peak voltage. The generated pulse stream is applied to the LED resulting in light emission of the controlled hue and of the controlled intensity.

A preamble signal is an OFDM signal, and is a real-part signal obtained by removing an imaginary-part signal from a signal in the time domain that is generated by an IFFT process being performed on a signal in the frequency domain obtained by assigning preamble data to subcarriers in accordance with a predetermined arrangement pattern. The predetermined arrangement pattern indicates that preamble data is assigned to any of subcarriers given numbers equal to or less than N/21 and the preamble data is not assigned to subcarriers given numbers more than N/21, where a plurality of subcarriers are numbered by integers from 0 to N1 (N is an integer) in ascending order with respect to the center frequency of each subcarrier.

Provided are a communication system that is capable of acquiring information having a relatively large data amount by a transmission unit while securing a communication speed of a transmission signal of transmission unit, and a transmission unit employed in communication system. Transmission unit transmits superimposition requesting data from a superimposition requesting unit to a second monitoring terminal in a transmission segment of transmission signal. Second monitoring terminal, upon receiving superimposition requesting data and with responding thereto, transmits, to transmission unit, monitoring data corresponding to a monitoring input from a sensor device with a superimposition signal superimposed on transmission signal as superimposition response data in a reply segment of transmission signal. Transmission unit, upon receiving superimposition response data composed of monitoring data with a superimposition communication unit, transmits control data to either a second control terminal or a first control terminal associated with this monitoring data in control table.

A distributed power system including multiple DC power sources and multiple power modules. The power modules include inputs coupled respectively to the DC power sources and outputs coupled in series to form a serial string. An inverter is coupled to the serial string. The inverter converts power input from the serial string to output power. A signaling mechanism between the inverter and the power module is adapted for controlling operation of the power modules. Also, for a protection method in the distributed power system, when the inverter stops production of the output power, each of the power modules is shut down and thereby the power input to the inverter is ceased.

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 bus station, a two-wire bus system, and methods for transmitting data in a two-wire bus system. The method includes: supplying a variable battery voltage to a first bus station and a second bus station, and transmitting data from the first bus station to the second bus station using a modulation signal that is superposed on the variable battery voltage, wherein the modulation signal is adjusted to follow a level of the variable battery voltage in a predefined manner.