Abstract: Data communication between two devices (11, 12) over the public powerline network (13) uses a multi carrier technology wherein a communication channel is divided into a plurality of subchannels by frequency division multiplexing. A partial power as part of the total transmission power and a partial rate as a fraction of the total data rate are assigned to each subchannel as follows: Initially, the same partial power is assigned to each subchannel and the S/N ratio of each subchannel is obtained. Starting with the subchannel of the lowest S/N ratio and proceeding to that of the highest S/N ratio, the following steps are performed for each subchannel: Firstly, the partial rate is assigned in accordance with the respective S/N ratio such as to result in a predetermined transmission error rate. The assigned partial rate is then quantised to an integral value.

Abstract: A data transmission method, particularly in electric networks, in which coded data are blockwise modulated onto several carrier frequencies within one or several particular frequency bands by an orthogonal frequency division multiplex method (OFDM) and in which the signal corresponding to a data block and obtained by inverse Fourier transformation is transferred to a receiver for a predetermined time duration (T), where individual signals succeed as signal blocks in time. In some embodiments, each signal is multiplied with a window function before transmission, the absolute value of the Fourier transform of which has a zero crossing at the respectively used carrier frequencies, and has secondary maxima, which have a damping of at least −30 dB in relation to the main maximum. In some embodiments, a digital filter can be used instead of the window function, the digital filter having an odd number of coefficients Ck, k=−m, . . . 0, . . .

Abstract: The present circuit serves for the transmission of information signals over the general electricity supply mains. It has a transducer (13) for the galvanic separation of the mains voltage. The mains side winding (L1) of the transducer is connected in series with a capacitor (C1) in order to separate the mains frequency from the frequency of the information signal. It is loosely coupled with the windings (L2, L3) of the transducer, being galvanically separated from the mains with a coupling degree between 0.8 and 0.98, whereby the transducer obtains a desired mains side stray inductance. The circuit is dimensioned so that it has a low impedance at the mains, when it is sending, and a high impedance, when it is receiving, that it provides a high level of the reception signal at the application side terminal and that it has a broadband balanced frequency response, which is largely independent of fluctuations of the mains impedance within a broad frequency range.